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Asian J Endosc Surg ISSN 1758-5902
O R I G I N A L A RT I C L E
Laparoscopic distal pancreatectomy: Educating surgeons about advanced laparoscopic surgery Yoshiharu Nakamura, Akira Matsushita, Akira Katsuno, Hiroki Sumiyoshi, Masato Yoshioka, Tetsuya Shimizu, Yoshiaki Mizuguchi & Eiji Uchida Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Nippon Medical School, Tokyo, Japan
Keywords Educating surgeons; laparoscopic distal pancreatectomy; left pancreatectomy Correspondence Yoshiharu Nakamura, Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan. Tel: +81 3 3822 2131 Fax: +81 3 5685 0989 Email: [email protected] Received 13 May 2014; revised 7 July 2014; accepted 10 July 2014 DOI:10.1111/ases.12131
Abstract Introduction: Laparoscopic distal pancreatectomy (Lap-DP) has been recognized worldwide as a feasible and highly beneficial procedure. The aim of this study is to investigate whether Lap-DP techniques are being implemented safely by surgeons training to perform this procedure. Methods: We retrospectively compared the perioperative outcomes of Lap-DP in patients operated on by the surgeon originating this procedure at our hospital (expert surgeon group [E group], n = 47) and patients operated on by surgeons training to perform this procedure (training surgeons group [T group], n = 53). Results: The median operating times for the E group and T group were 321 min (range, 150–653 min) and 314 min (range, 173–629 min), respectively; these times were not significantly different (P = 0.4769). The median blood loss in the T group (100 mL; range, 0–1950 mL) was significantly smaller than in the E group (280 mL; range, 0–1920 mL) (P = 0.0003). There were no significant intergroup differences in other operative results: combined operation ratio, spleen- and splenic vessels-preserving ratio, hand-assisted procedure ratio, and the ratio of transition to open. The frequency of pancreatic fistulas in the E group and T group was 12.8% and 16.9%, respectively; these rates were not significantly different (P = 0.5886). There were no significant differences between the two groups in terms of other complications and reoperation rates. The median hospital stay for the E group was significantly shorter than for the T group (10 vs 13 days; P = 0.0307). Conclusion: This retrospective analysis shows that teaching safe Lap-DP techniques to surgeons is reflected in stable perioperative outcomes.
Introduction Laparoscopic surgery is now widely performed for a variety of reasons: (i) the procedure results in a small surgical wound and cosmetically favorable outcomes; (ii) areas that cannot be seen with the naked eye can be clearly visualized with a laparoscope, allowing more detailed procedures and reducing blood loss; and (iii) minimal surgical invasiveness shortens postoperative hospital stays, thus lowering costs. These advantages also apply to the use of laparoscopic surgery to treat pancreatic diseases. Over the past few years, there have been an increasing number of reports on the feasibility of laparo-
scopic distal pancreatectomy (Lap-DP) (1–7). Some meta-analyses have compared Lap-DP and open distal pancreatectomy, and all have indicated that Lap-DP is superior because it is less invasive (8–13). Today, Lap-DP is recognized worldwide as a feasible and highly beneficial procedure. It is important to teach easily reproducible techniques to surgeons learning the procedure to ensure they adopt safe techniques when embarking on a new surgical modality. Given that many agree that Lap-DP represents the gold standard technique for lesions in the left pancreas (14), we think that the next generation of surgeons needs to be taught the techniques used in Lap-DP so they can perform this procedure safely.
Asian J Endosc Surg 7 (2014) 295–300 © 2014 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Wiley Publishing Asia Pty Ltd
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Teaching Lap-DP to the next generation
Y Nakamura et al.
The purpose of this study was to investigate whether Lap-DP techniques are being implemented safely by surgeons being trained in the procedure. This study compared the clinical outcomes of Lap-DP performed by a teaching (expert) surgeon with those of Lap-DP performed by surgeons who had studied the necessary techniques at our hospital before performing the surgical procedure. Study design The study was a retrospective comparative study over a limited timeframe.
Materials and Methods This study included 100 patients with a lesion in the distal pancreas who underwent Lap-DP at the Nippon Medical School Hospital between January 2004 and December 2013. Forty-seven of the 100 patients underwent Lap-DP between January 2004 (after Lap-DP was first approved by the hospital’s Ethics Review Board) and December 2009; all of these procedures were performed by Nippon Medical School’s expert Lap-DP surgeon (YN), with 20 years’ experience as a gastrointestinal surgeon. The remaining 53 patients underwent Lap-DP between January 2010 and December 2013; all of these procedures were performed by one of three gastrointestinal surgeons (AM, with 15 years’ experience; MY, with 15 years’ experience; and TS, with 12 years’ experience). These three surgeons are certified surgeons approved by the Japanese Society of Gastroenterological Surgery. They had already performed laparoscopic cholecystectomy (Lap-C) in over 50 cases and open pancreatectomy in over 10 cases. They started to perform Lap-DP after gaining laparoscopist experience in at least five cases of Lap-DP or laparoscopic pancreaticoduodenectomy. For this second group of patients, the expert surgeon was involved in all operations as a technical coach. We retrospectively compared the perioperative outcomes between the patients undergoing Lap-DP performed by YN (expert surgeon group [E group]) and by the surgeons training to perform the procedure (training surgeons group [T group]). All 100 patients gave written informed consent to undergo Lap-DP. The patients were all Japanese. The average age was 57.9 years in the E group and 55.8 years in the T group. The E group included 13 men and 34 women with an average BMI of 22.5 kg/m2. The T group included 15 men and 38 women with an average BMI of 21.8 kg/m2. Eight of the 47 patients (17.0%) in the E group had a history of abdominal surgery, and 14 of the 53 patients (26.4%) in the T group had a history of abdominal surgery. The mean
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ASA score was 1.74 in the E group and 1.56 in the T group. Final diagnoses were based on either rapid pathological diagnosis or postoperative histopathological diagnosis. A diagnosis of benign pancreatic cystic disease was made in 22 patients in the E group (serous cystic neoplasm [n = 10], mucinous cystic neoplasm [n = 8], solid pseudopapillary neoplasm [n = 1], and other benign pancreatic cystic disease [n = 3]) and for 26 patients in the T group (mucinous cystic neoplasm [n = 13], solid pseudopapillary neoplasm [n = 5], intraductal papillary mucinous neoplasm [n = 4], serous cystic neoplasm [n = 1], and other benign pancreatic disease [n = 3]). A diagnosis of pancreatic cancer was made for 10 patients in the E group (invasive ductal adenocarcinoma [n = 8], cancer derived from intraductal papillary mucinous neoplasm [n = 1], and cancer derived from mucinous cystic neoplasm [n = 1]) and for 10 patients in the T group (invasive ductal adenocarcinoma [n = 7], aciner cell carcinoma [n = 1], and cancer derived from intraductal papillary mucinous neoplasm [n = 2]). There were no cases of borderline resectable pancreatic cancer, as defined by the National Comprehensive Cancer Network Clinical Practice Guidelines (15,16), in the either group. A diagnosis of neuroendocrine tumor was made for nine patients in the E group (insulinoma [n = 4], non-functioning tumor [n = 4], and neuroendocrine carcinoma [NEC] [n = 1]) and for 14 patients in the T group (insulinoma [n = 7], non-functioning tumor [n = 5], glucagonoma (n = 1), and NEC (n = 1)]. A diagnosis of metastatic tumor was made for three patients in the E group and one patient in the T group. Other diseases were diagnosed for three patients in the E group (malignant lymphoma [n = 1] and intrapancreatic accessory spleen [n = 2]) and for two patients in the T group (intra-pancreatic accessory spleen [n = 2]). Malignant diseases were diagnosed in 15 of the 47 patients in the E group (32%) (pancreatic cancer [n = 10], metastatic tumor [n = 3], NEC [n = 1], and malignant lymphoma [n = 1]) and in 12 of the 53 patients in the T group (23%) (pancreatic cancer [n = 10], metastatic tumor [n = 1], and NEC [n = 1]). The mean tumor size was 43.8 mm in the E group and 35.5 mm in the T group. In the E group, the tumors were located in the pancreatic body (Pb) in 18 patients, pancreatic tail (Pt) in 21 patients, and in both locations (Pb-Pt) in 8 patients. In the T group, the tumors were located in the Pb in 14 patients, Pt in 20 patients, and Pb-Pt in 19 patients (Table 1). Pancreatic fistula was defined according to the 2005 International Study Group of Pancreatic Fistula, and clinical leaks were classified into grades B and C (17,18). Statistical analysis was performed using the SPSS version 19.0 software program (SPSS Inc., Chicago, USA). Data were expressed as mean ± SD or the median.
Asian J Endosc Surg 7 (2014) 295–300 © 2014 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Wiley Publishing Asia Pty Ltd
Teaching Lap-DP to the next generation
Y Nakamura et al.
Table 1 Preoperative characteristics of the 100 patients who underwent Lap-DP Characteristics
E group (n = 47)
T group (n = 53)
P-value
Age, mean ± SD (years) Sex (men/women) BMI, mean ± SD (kg/m2) Previous abdominal surgery (yes/no) ASA score, mean ± SD Clinical diagnosis (n)† Pancreatic cystic diseases PDAC Neuro-endocrine tumor Metastatic tumor Other Malignant disease ratio Tumor size, mean ± SD (mm) Tumor location (Pb/Pt/Pb-Pt‡)
57.9 ± 16.6 13/34 22.5 ± 2.9 8/39 1.74 ± 0.53
55.8 ± 18.8 15/38 21.8 ± 2.9 14/39 1.56 ± 0.53
0.554 0.9431 0.2394 0.2577 0.0982
22 10 9 3 3 15/47 (31.9%) 43.8 ± 31.7 18/21/8
26 10 14 1 2 12/53 (22.6%) 35.5 ± 24.3 14/20/19
0.2972 0.1462 0.0972
†Clinical diagnosis based on histopathology after operation. ‡Tumor located in both Pb and Pt. All patients were Japanese. E group, expert surgeon group; Lap-DP, laparoscopic distal pancreatectomy; Pb, pancreatic body; PDAC, pancreatic ductal adenocarcinoma; Pt, pancreatic tail; T group, training surgeons group.
Data from each period were compared using an unpaired t-test, Mann–Whitney U-test, or Fisher’s exact test, as appropriate. P-values less than 0.05 were considered significant. Operative technique We have previously described our technique for Lap-DP in a number of English-language papers (4,19,20). Each patient was immobilized in the supine position, and we adjusted patient angles as needed by rotating the operating table. A 12-mm umbilical trocar was used to insert the laparoscope and endoscopic linear stapler. On the right side, a 5-mm trocar was inserted below the right costal arch between the right mammillary line and the upper abdominal median line, and another 5-mm trocar was inserted at 10 cm caudal to the first 5-mm trocar. On the left side, a 5-mm trocar was placed in the anterior subcostal region at the midaxillary line, and a 12-mm trocar was inserted at the center point between the umbilical trocar and the 5-mm trocar in the anterior subcostal region (Figure 1). Abdominal air pressure was set at 7–10 mmHg. After opening the omental bursa, intraoperative ultrasound was performed to determine the location of the tumor and pancreatic resection. Following exposure of the peripancreatic vessels and/or lymph node dissection, the pancreas was resected with an endoscopic linear stapler. The pancreatic resection stump was not subjected to oversewing or fibrin glue application. The resected tissue was placed in a surgical bag for removal. During spleen-preserving Lap-DP, the splenic artery and vein
Figure 1 Depending on the tumor size, five trocars were generally inserted into the following locations: (1) a 12-mm trocar at the navel; (2) a 5-mm trocar between the right mammillary line and the upper abdominal median line, below the costal arch; (3) a 5-mm trocar placed 10 cm caudal to the 5-mm trocar below the costal arch; (4) a 5-mm trocar on the left side in the anterior subcostal region at the midaxillary line; and (5) a 12-mm trocar at the center point between the navel and the 5-mm trocar in the left anterior subcostal region.
were conserved in all patients, and the procedure by Warshaw was not employed (21).
Results There were no significant differences between the E and T groups for the following clinical factors: age, sex, BMI, history of abdominal surgery, ASA score, final diagnoses of disease, malignancy ratio, tumor size, and tumor location (Table 1).
Asian J Endosc Surg 7 (2014) 295–300 © 2014 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Wiley Publishing Asia Pty Ltd
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Table 2 Intraoperative results of Lap-DP
Median length of operation, min (range) Median blood loss, mL (range) Blood transfusion (yes/no) Combined operation (yes/no) Spleen- and splenic vessels-preserving (yes/no) Hand-assisted procedure (yes/no) Conversion (yes/no)
E group (n = 47)
T group (n = 53)
P-value
321 (150–653) 280 (0–1920) 3/44 9/38 11/36 2/45 2/45
314 (173–629) 100 (0–1950) 2/51 6/47 11/42 0/53 0/53
0.4769 0.0003 0.6636 0.2739 0.7496 0.2184 0.2184
E group, expert surgeon group; Lap-DP, laparoscopic distal pancreatectomy; T group, training surgeons group.
The median operating time was 321 min (range, 150– 653 min) in the E group and 314 min (range, 173– 629 min) in the T group; there was no significant intergroup difference (P = 0.4769). The median blood loss was 280 mL (range, 0–1920 mL) in the E group and 100 mL (range, 0–1950 mL) in the T group; there was a significant intergroup difference (P = 0.0003). However, the ratio of blood transfusion during operation was 6.4% (3/47) for the E group and 3.8% (2/53) for the T group, with no significant intergroup difference (P = 0.6636). There were no significant intergroup differences in other operative results: combined operation ratio, spleen- and splenic vessels-preserving ratio, hand-assisted procedure ratio, and the ratio of transition to open (Table 2). Grade B or C pancreatic fistulas were observed in 12.8% of patients (6/47) in the E group and 16.9% of patients (9/53) in the T group; there were no significant intergroup differences (P = 0.5886). The pancreatic fistulas resolved with conservative treatment for all patients in both groups. For postoperative complications other than pancreatic fistula, the following complications were observed in 3 of 47 patients (6.4%) in the E group: port-site hernia (n = 1), methicillin-resistant Staphylococcus aureus pneumonia (n = 1), and intra-abdominal hemorrhage after heparinization (n = 1). The following complications were observed in 3 of 53 patients (5.7%) in the T group: respiratory failure (n = 1), hemorrhage from the pancreatic stump (n = 1), and hemorrhage from the greater omentum (n = 1). There were no significant intergroup differences related to these other complications (P > 0.9999). The patient with the port-site hernia in the E group was operated on again. Hemostasis was achieved conservatively for the hemorrhages from the pancreatic stump and greater omentum in the two patients in the T group, but both patients subsequently underwent laparoscopic surgery again to eliminate intraabdominal hematomas and wash the intra-abdominal area with saline. There were no significant intergroup differences in terms of the reoperation ratio (P > 0.9999). Late-phase complications were observed in 4 of 47 patients in the E group (port-site hernia [n = 1], onset of
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diabetes mellitus [n = 2], and pseudocyst formation [n = 1]) and in 1 of 53 patients in the T group (port-site hernia). There were no significant intergroup differences (P = 0.1841). The median postoperative hospital stay was 10 days (range, 6–76 days) in the E group and 13 days (range, 7–77 days) in the T group. The median hospital stay for the E group was significantly shorter than for the T group (P = 0.0307) (Table 3). In a subgroup analysis of oncologic outcomes in patients undergoing Lap-DP for pancreatic adenocarcinoma, total lymph node harvest and margin status did not differ significantly between the two groups (Table 3).
Discussion Laparoscopic pancreatectomy was first reported by Gagner and Pomp in 1994 (22), and since then, there has been a rapid increase in the number of papers reporting the effectiveness of this technique. Most of the reports cite reduced blood loss and shorter hospital stay as the main advantages of laparoscopic pancreatectomy (13,23– 25). More recently, a number of meta-analyses have compared Lap-DP with laparotomy in terms of surgical outcomes (8–13). All of these studies suggest that Lap-DP produces beneficial outcomes. Now that Lap-DP has become widely recognized as a well-established surgical procedure like Lap-C, it is time to consider how to educate surgeons training to perform this technique to ensure it is passed on safely. Lap-DP was first used at our hospital in January 2004. For the first 6 years, the surgeon who introduced the procedure performed all Lap-DP operations and confirmed its feasibility, safety, and efficacy (4). In January 2010, a number of more junior surgeons started performing the procedure, with the surgeon who introduced the procedure acting as a coach during surgery. This study compared the outcomes of surgery performed by an expert surgeon and by surgeons training to perform LapDP; it showed that the change in surgeons did not have a negative impact on operating times and blood loss during surgery. The study suggested that Lap-DP could be safely
Asian J Endosc Surg 7 (2014) 295–300 © 2014 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Wiley Publishing Asia Pty Ltd
Teaching Lap-DP to the next generation
Y Nakamura et al.
Table 3 Postoperative results of Lap-DP
Grade B or C pancreatic fistula†, n (%) Other complications, n (%) Reoperation, n (%) Late-phase complications, n (%) Median LOS, days (range) Mortality (n) Oncologic outcomes in PDAC (n) Retrieved lymph nodes, mean ± SD (n) R0 resection ratio
E group (n = 47)
T group (n = 53)
P-value
6/47 (12.8) 3/47 (6.4) 1/47 (2.1) 4/47 (8.5) 10 (6–76) 0 10 17.3 ± 10.1 80%
9/53 (16.9) 3/53 (5.7) 2/53 (3.8) 1/53 (1.9) 13 (7–77) 0 10 19.0 ± 7.8 90%
0.5886 >0.9999 >0.9999 0.1841 0.0307
0.6377 >0.9999
†According to International Study Group of Pancreatic Fistula. E group, expert surgeon group; Lap-DP, laparoscopic distal pancreatectomy; LOS, length of stay; PDAC, pancreatic ductal adenocarcinoma; T group, training surgeons group.
performed in a standardized way within the same hospital if the surgeon has acted as a laparoscopist during laparoscopic pancreatectomies and has performed Lap-C in at least 50 patients and open pancreatectomy in at least 10 patients. During laparoscopic surgery, all members of the surgical team share the same visual field. This provides a major advantage for teaching purposes compared with laparotomy. Even those not part of the surgical team can view the same visual field as the surgeon via a monitor relay, which is extremely useful for observational studies of surgery. With laparotomy, the lead surgeon monopolizes the best visual field, so there are limited opportunities for effective observational learning by surgical assistants or students. The pancreas can be very difficult to see because it is sited deep within the body, so it is extremely difficult to learn laparotomic techniques unless you are performing the surgery. Unlike laparoscopic pancreaticoduodenectomy, Lap-DP does not require specialized techniques for reconstructive surgery, so it is suited to observational study in the same way that Lap-C and laparoscopic adrenalectomy methods are. It is important to watch numerous standardized Lap-DP procedures in order to gain an understanding of the dissection and surgical procedures required. In this study, there was no negative impact on the percentage of postoperative complications occurring in the T and E groups, including pancreatic fistula. There was also no significant difference in the percentage of patients requiring reoperation. Postoperative hospital stays were significantly longer in the T group than in the E group. This may have occurred because the T-group operations were conducted by surgeons training to perform Lap-DP who may have delayed discharge in order to allow longer postoperative observation of their patients. On average, patients in the T group spent only 3 more days in the hospital than those in the E group. As
such, we do not think the difference in hospital stay reflects a failure in terms of education on patient safety. In patients with pancreatic adenocarcinoma, total lymph node harvest and margin status did not differ significantly between the two groups (Table 3). We think the results suggest that the T-group surgeons had mastered the techniques for lymph node dissection and margin-free resection. Recently published papers show that total lymph node harvest and margin status do not differ between laparoscopic pancreatectomy and laparotomy for pancreatic adenocarcinoma (9,13,23). The literature also contains reports on new surgical techniques to improve oncological curability (26,27). A laparoscope allows the visual field to be magnified ×10–15, and this magnified view may allow greater fine dissection during resection than laparotomy. This may result in resection techniques that offer greater curability. It is very useful to be able to teach surgical techniques to training surgeons using the visual field that is shared with the surgeon and the surgical assistants and that is magnified thanks to laparoscopic technology. This retrospective analysis, performed over a limited time frame, shows that teaching safe Lap-DP techniques to surgeons is reflected in stable perioperative outcomes. Prospective randomized trials should be performed to demonstrate this concept.
Acknowledgment The authors have no conflicts of interest or financial ties to disclose.
References 1. Kooby DA, Gillespie T, Bentrem D et al. Left-sided pancreatectomy: A multicenter comparison of laparoscopic and open approaches. Ann Surg 2008; 248: 438–446.
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2. Kim SC, Park KT, Hwang JW et al. Comparative analysis of clinical outcomes for laparoscopic distal pancreatic resection and open distal pancreatic resection at a single institution. Surg Endosc 2008; 22: 2261–2268. 3. Baker MS, Bentrem DJ, Ujiki MB. A prospective single institution comparison of peri-operative outcomes for laparoscopic and open distal pancreatectomy. Surgery 2009; 146: 635–645. 4. Nakamura Y, Uchida E, Aimoto T et al. Clinical outcome of laparoscopic distal pancreatectomy. J Hepatobiliary Pancreat Surg 2009; 16: 35–41. 5. Jayaraman S, Gonen M, Brennan MF et al. Laparoscopic distal pancreatectomy: Evolution of a technique at a single institution. J Am Coll Surg 2010; 211: 503–509. 6. Vijan SS, Ahmed KA, Harmsen WS et al. Laparoscopic vs open distal pancreatectomy: A single-institution comparative study. Arch Surg 2010; 145: 616–621. 7. Butturini G, Inama M, Malleo G et al. Perioperative and long-term results of laparoscopic spleen-preserving distal pancreatectomy with or without splenic vessels conservation: A retrospective analysis. J Surg Oncol 2012; 105: 387– 392. 8. Venkat R, Edil BH, Schulick RD et al. Laparoscopic distal pancreatectomy is associated with significantly less overall morbidity compared to the open technique: A systematic review and meta-analysis. Ann Surg 2012; 255: 1048–1059. 9. Sui CJ, Li B, Yang JM et al. Laparoscopic versus open distal pancreatectomy: A meta-analysis. Asian J Surg 2012; 35: 1–8. 10. Jin T, Altaf K, Xiong JJ et al. A systematic review and metaanalysis of studies comparing laparoscopic and open distal pancreatectomy. HPB (Oxford) 2012; 14: 711–724. 11. Xie K, Zhu YP, Xu XW et al. Laparoscopic distal pancreatectomy is as safe and feasible as open procedure: A meta-analysis. World J Gastroenterol 2012; 18: 1959–1967. 12. Pericleous S, Middleton N, McKay SC et al. Systematic review and meta-analysis of case-matched studies comparing open and laparoscopic distal pancreatectomy: Is it a safe procedure? Pancreas 2012; 41: 993–1000. 13. Nakamura M & Nakashima H. Laparoscopic distal pancreatectomy and pancreatoduodenectomy: Is it worthwhile? A meta-analysis of laparoscopic pancreatectomy. J Hepatobiliary Pancreat Sci 2013; 20: 421–428. 14. Abu Hilal M & Takhar AS. Laparoscopic left pancreatectomy: Current concepts. Pancreatology 2013; 13: 443–448.
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15. Callery MP, Chang KJ, Fishman EK et al. Pretreatment assessment of resectable and borderline resectable pancreatic cancer: Expert consensus statement. Ann Surg Oncol 2009; 16: 1727–1733. 16. National Comprehensive Cancer Network (NCCN). Clinical practice guidelines pancreatic adenocarcinoma. Accessed May 31, 2014. 17. Bassi C, Dervenis C, Butturini G et al. Postoperative pancreatic fistula: An international study group (ISGPF) definition. Surgery 2005; 138: 8–13. 18. Pratt W, Maithel SK, Vanounou T et al. Postoperative pancreatic fistulas are not equivalent after proximal, distal, and central pancreatectomy. J Gastrointest Surg 2006; 10: 1264– 1279. 19. Nakamura Y, Uchida E, Nomura T et al. Laparoscopic pancreatic resection: Some benefits of evolving surgical techniques. J Hepatobiliary Pancreat Surg 2009; 16: 741–748. 20. Nakamura Y, Matsumoto S, Tajiri T et al. Safe technique for laparoscopic distal pancreatectomy involving a large cystic tumor. J Nippon Med Sch 2011; 78: 374–378. 21. Warshaw AL. Conservation of the spleen with distal pancreatectomy. Arch Surg 1988; 123: 550–553. 22. Gagner M & Pomp A. Laparoscopic pylorus-preserving pancreatoduodenectomy. Surg Endosc 1994; 8: 408–410. 23. Mesleh MG, Stauffer JA, Asbun HJ. Minimally invasive surgical techniques for pancreatic cancer: Ready for prime time? J Hepatobiliary Pancreat Sci 2013; 20: 578–582. 24. Misawa T, Ito R, Futagawa Y et al. Single-incision laparoscopic distal pancreatectomy with or without splenic preservation: How we do it. Asian J Endosc Surg 2012; 5: 195–199. 25. Sunagawa H, Mayama Y, Orokawa T et al. Laparoscopic total remnant pancreatectomy after laparoscopic pancreaticoduodenectomy. Asian J Endosc Surg 2014; 7: 71–74. 26. Nakamura Y, Matsumoto S, Matsushita A et al. Pancreaticojejunostomy with closure of the pancreatic stump by endoscopic linear stapler in laparoscopic pancreaticoduodenectomy: A reliable technique and benefits for pancreatic resection. Asian J Endosc Surg 2012; 5: 191–194. 27. Choi SH, Kang CM, Lee WJ et al. Laparoscopic modified anterior RAMPS in well-selected left-sided pancreatic cancer: Technical feasibility and interim results. Surg Endosc 2011; 25: 2360–2361.
Asian J Endosc Surg 7 (2014) 295–300 © 2014 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Wiley Publishing Asia Pty Ltd
Asian J Endosc Surg ISSN 1758-5902
O R I G I N A L A RT I C L E
Laparoscopic distal pancreatectomy: Educating surgeons about advanced laparoscopic surgery Yoshiharu Nakamura, Akira Matsushita, Akira Katsuno, Hiroki Sumiyoshi, Masato Yoshioka, Tetsuya Shimizu, Yoshiaki Mizuguchi & Eiji Uchida Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Nippon Medical School, Tokyo, Japan
Keywords Educating surgeons; laparoscopic distal pancreatectomy; left pancreatectomy Correspondence Yoshiharu Nakamura, Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan. Tel: +81 3 3822 2131 Fax: +81 3 5685 0989 Email: [email protected] Received 13 May 2014; revised 7 July 2014; accepted 10 July 2014 DOI:10.1111/ases.12131
Abstract Introduction: Laparoscopic distal pancreatectomy (Lap-DP) has been recognized worldwide as a feasible and highly beneficial procedure. The aim of this study is to investigate whether Lap-DP techniques are being implemented safely by surgeons training to perform this procedure. Methods: We retrospectively compared the perioperative outcomes of Lap-DP in patients operated on by the surgeon originating this procedure at our hospital (expert surgeon group [E group], n = 47) and patients operated on by surgeons training to perform this procedure (training surgeons group [T group], n = 53). Results: The median operating times for the E group and T group were 321 min (range, 150–653 min) and 314 min (range, 173–629 min), respectively; these times were not significantly different (P = 0.4769). The median blood loss in the T group (100 mL; range, 0–1950 mL) was significantly smaller than in the E group (280 mL; range, 0–1920 mL) (P = 0.0003). There were no significant intergroup differences in other operative results: combined operation ratio, spleen- and splenic vessels-preserving ratio, hand-assisted procedure ratio, and the ratio of transition to open. The frequency of pancreatic fistulas in the E group and T group was 12.8% and 16.9%, respectively; these rates were not significantly different (P = 0.5886). There were no significant differences between the two groups in terms of other complications and reoperation rates. The median hospital stay for the E group was significantly shorter than for the T group (10 vs 13 days; P = 0.0307). Conclusion: This retrospective analysis shows that teaching safe Lap-DP techniques to surgeons is reflected in stable perioperative outcomes.
Introduction Laparoscopic surgery is now widely performed for a variety of reasons: (i) the procedure results in a small surgical wound and cosmetically favorable outcomes; (ii) areas that cannot be seen with the naked eye can be clearly visualized with a laparoscope, allowing more detailed procedures and reducing blood loss; and (iii) minimal surgical invasiveness shortens postoperative hospital stays, thus lowering costs. These advantages also apply to the use of laparoscopic surgery to treat pancreatic diseases. Over the past few years, there have been an increasing number of reports on the feasibility of laparo-
scopic distal pancreatectomy (Lap-DP) (1–7). Some meta-analyses have compared Lap-DP and open distal pancreatectomy, and all have indicated that Lap-DP is superior because it is less invasive (8–13). Today, Lap-DP is recognized worldwide as a feasible and highly beneficial procedure. It is important to teach easily reproducible techniques to surgeons learning the procedure to ensure they adopt safe techniques when embarking on a new surgical modality. Given that many agree that Lap-DP represents the gold standard technique for lesions in the left pancreas (14), we think that the next generation of surgeons needs to be taught the techniques used in Lap-DP so they can perform this procedure safely.
Asian J Endosc Surg 7 (2014) 295–300 © 2014 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Wiley Publishing Asia Pty Ltd
295
Teaching Lap-DP to the next generation
Y Nakamura et al.
The purpose of this study was to investigate whether Lap-DP techniques are being implemented safely by surgeons being trained in the procedure. This study compared the clinical outcomes of Lap-DP performed by a teaching (expert) surgeon with those of Lap-DP performed by surgeons who had studied the necessary techniques at our hospital before performing the surgical procedure. Study design The study was a retrospective comparative study over a limited timeframe.
Materials and Methods This study included 100 patients with a lesion in the distal pancreas who underwent Lap-DP at the Nippon Medical School Hospital between January 2004 and December 2013. Forty-seven of the 100 patients underwent Lap-DP between January 2004 (after Lap-DP was first approved by the hospital’s Ethics Review Board) and December 2009; all of these procedures were performed by Nippon Medical School’s expert Lap-DP surgeon (YN), with 20 years’ experience as a gastrointestinal surgeon. The remaining 53 patients underwent Lap-DP between January 2010 and December 2013; all of these procedures were performed by one of three gastrointestinal surgeons (AM, with 15 years’ experience; MY, with 15 years’ experience; and TS, with 12 years’ experience). These three surgeons are certified surgeons approved by the Japanese Society of Gastroenterological Surgery. They had already performed laparoscopic cholecystectomy (Lap-C) in over 50 cases and open pancreatectomy in over 10 cases. They started to perform Lap-DP after gaining laparoscopist experience in at least five cases of Lap-DP or laparoscopic pancreaticoduodenectomy. For this second group of patients, the expert surgeon was involved in all operations as a technical coach. We retrospectively compared the perioperative outcomes between the patients undergoing Lap-DP performed by YN (expert surgeon group [E group]) and by the surgeons training to perform the procedure (training surgeons group [T group]). All 100 patients gave written informed consent to undergo Lap-DP. The patients were all Japanese. The average age was 57.9 years in the E group and 55.8 years in the T group. The E group included 13 men and 34 women with an average BMI of 22.5 kg/m2. The T group included 15 men and 38 women with an average BMI of 21.8 kg/m2. Eight of the 47 patients (17.0%) in the E group had a history of abdominal surgery, and 14 of the 53 patients (26.4%) in the T group had a history of abdominal surgery. The mean
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ASA score was 1.74 in the E group and 1.56 in the T group. Final diagnoses were based on either rapid pathological diagnosis or postoperative histopathological diagnosis. A diagnosis of benign pancreatic cystic disease was made in 22 patients in the E group (serous cystic neoplasm [n = 10], mucinous cystic neoplasm [n = 8], solid pseudopapillary neoplasm [n = 1], and other benign pancreatic cystic disease [n = 3]) and for 26 patients in the T group (mucinous cystic neoplasm [n = 13], solid pseudopapillary neoplasm [n = 5], intraductal papillary mucinous neoplasm [n = 4], serous cystic neoplasm [n = 1], and other benign pancreatic disease [n = 3]). A diagnosis of pancreatic cancer was made for 10 patients in the E group (invasive ductal adenocarcinoma [n = 8], cancer derived from intraductal papillary mucinous neoplasm [n = 1], and cancer derived from mucinous cystic neoplasm [n = 1]) and for 10 patients in the T group (invasive ductal adenocarcinoma [n = 7], aciner cell carcinoma [n = 1], and cancer derived from intraductal papillary mucinous neoplasm [n = 2]). There were no cases of borderline resectable pancreatic cancer, as defined by the National Comprehensive Cancer Network Clinical Practice Guidelines (15,16), in the either group. A diagnosis of neuroendocrine tumor was made for nine patients in the E group (insulinoma [n = 4], non-functioning tumor [n = 4], and neuroendocrine carcinoma [NEC] [n = 1]) and for 14 patients in the T group (insulinoma [n = 7], non-functioning tumor [n = 5], glucagonoma (n = 1), and NEC (n = 1)]. A diagnosis of metastatic tumor was made for three patients in the E group and one patient in the T group. Other diseases were diagnosed for three patients in the E group (malignant lymphoma [n = 1] and intrapancreatic accessory spleen [n = 2]) and for two patients in the T group (intra-pancreatic accessory spleen [n = 2]). Malignant diseases were diagnosed in 15 of the 47 patients in the E group (32%) (pancreatic cancer [n = 10], metastatic tumor [n = 3], NEC [n = 1], and malignant lymphoma [n = 1]) and in 12 of the 53 patients in the T group (23%) (pancreatic cancer [n = 10], metastatic tumor [n = 1], and NEC [n = 1]). The mean tumor size was 43.8 mm in the E group and 35.5 mm in the T group. In the E group, the tumors were located in the pancreatic body (Pb) in 18 patients, pancreatic tail (Pt) in 21 patients, and in both locations (Pb-Pt) in 8 patients. In the T group, the tumors were located in the Pb in 14 patients, Pt in 20 patients, and Pb-Pt in 19 patients (Table 1). Pancreatic fistula was defined according to the 2005 International Study Group of Pancreatic Fistula, and clinical leaks were classified into grades B and C (17,18). Statistical analysis was performed using the SPSS version 19.0 software program (SPSS Inc., Chicago, USA). Data were expressed as mean ± SD or the median.
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Table 1 Preoperative characteristics of the 100 patients who underwent Lap-DP Characteristics
E group (n = 47)
T group (n = 53)
P-value
Age, mean ± SD (years) Sex (men/women) BMI, mean ± SD (kg/m2) Previous abdominal surgery (yes/no) ASA score, mean ± SD Clinical diagnosis (n)† Pancreatic cystic diseases PDAC Neuro-endocrine tumor Metastatic tumor Other Malignant disease ratio Tumor size, mean ± SD (mm) Tumor location (Pb/Pt/Pb-Pt‡)
57.9 ± 16.6 13/34 22.5 ± 2.9 8/39 1.74 ± 0.53
55.8 ± 18.8 15/38 21.8 ± 2.9 14/39 1.56 ± 0.53
0.554 0.9431 0.2394 0.2577 0.0982
22 10 9 3 3 15/47 (31.9%) 43.8 ± 31.7 18/21/8
26 10 14 1 2 12/53 (22.6%) 35.5 ± 24.3 14/20/19
0.2972 0.1462 0.0972
†Clinical diagnosis based on histopathology after operation. ‡Tumor located in both Pb and Pt. All patients were Japanese. E group, expert surgeon group; Lap-DP, laparoscopic distal pancreatectomy; Pb, pancreatic body; PDAC, pancreatic ductal adenocarcinoma; Pt, pancreatic tail; T group, training surgeons group.
Data from each period were compared using an unpaired t-test, Mann–Whitney U-test, or Fisher’s exact test, as appropriate. P-values less than 0.05 were considered significant. Operative technique We have previously described our technique for Lap-DP in a number of English-language papers (4,19,20). Each patient was immobilized in the supine position, and we adjusted patient angles as needed by rotating the operating table. A 12-mm umbilical trocar was used to insert the laparoscope and endoscopic linear stapler. On the right side, a 5-mm trocar was inserted below the right costal arch between the right mammillary line and the upper abdominal median line, and another 5-mm trocar was inserted at 10 cm caudal to the first 5-mm trocar. On the left side, a 5-mm trocar was placed in the anterior subcostal region at the midaxillary line, and a 12-mm trocar was inserted at the center point between the umbilical trocar and the 5-mm trocar in the anterior subcostal region (Figure 1). Abdominal air pressure was set at 7–10 mmHg. After opening the omental bursa, intraoperative ultrasound was performed to determine the location of the tumor and pancreatic resection. Following exposure of the peripancreatic vessels and/or lymph node dissection, the pancreas was resected with an endoscopic linear stapler. The pancreatic resection stump was not subjected to oversewing or fibrin glue application. The resected tissue was placed in a surgical bag for removal. During spleen-preserving Lap-DP, the splenic artery and vein
Figure 1 Depending on the tumor size, five trocars were generally inserted into the following locations: (1) a 12-mm trocar at the navel; (2) a 5-mm trocar between the right mammillary line and the upper abdominal median line, below the costal arch; (3) a 5-mm trocar placed 10 cm caudal to the 5-mm trocar below the costal arch; (4) a 5-mm trocar on the left side in the anterior subcostal region at the midaxillary line; and (5) a 12-mm trocar at the center point between the navel and the 5-mm trocar in the left anterior subcostal region.
were conserved in all patients, and the procedure by Warshaw was not employed (21).
Results There were no significant differences between the E and T groups for the following clinical factors: age, sex, BMI, history of abdominal surgery, ASA score, final diagnoses of disease, malignancy ratio, tumor size, and tumor location (Table 1).
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Table 2 Intraoperative results of Lap-DP
Median length of operation, min (range) Median blood loss, mL (range) Blood transfusion (yes/no) Combined operation (yes/no) Spleen- and splenic vessels-preserving (yes/no) Hand-assisted procedure (yes/no) Conversion (yes/no)
E group (n = 47)
T group (n = 53)
P-value
321 (150–653) 280 (0–1920) 3/44 9/38 11/36 2/45 2/45
314 (173–629) 100 (0–1950) 2/51 6/47 11/42 0/53 0/53
0.4769 0.0003 0.6636 0.2739 0.7496 0.2184 0.2184
E group, expert surgeon group; Lap-DP, laparoscopic distal pancreatectomy; T group, training surgeons group.
The median operating time was 321 min (range, 150– 653 min) in the E group and 314 min (range, 173– 629 min) in the T group; there was no significant intergroup difference (P = 0.4769). The median blood loss was 280 mL (range, 0–1920 mL) in the E group and 100 mL (range, 0–1950 mL) in the T group; there was a significant intergroup difference (P = 0.0003). However, the ratio of blood transfusion during operation was 6.4% (3/47) for the E group and 3.8% (2/53) for the T group, with no significant intergroup difference (P = 0.6636). There were no significant intergroup differences in other operative results: combined operation ratio, spleen- and splenic vessels-preserving ratio, hand-assisted procedure ratio, and the ratio of transition to open (Table 2). Grade B or C pancreatic fistulas were observed in 12.8% of patients (6/47) in the E group and 16.9% of patients (9/53) in the T group; there were no significant intergroup differences (P = 0.5886). The pancreatic fistulas resolved with conservative treatment for all patients in both groups. For postoperative complications other than pancreatic fistula, the following complications were observed in 3 of 47 patients (6.4%) in the E group: port-site hernia (n = 1), methicillin-resistant Staphylococcus aureus pneumonia (n = 1), and intra-abdominal hemorrhage after heparinization (n = 1). The following complications were observed in 3 of 53 patients (5.7%) in the T group: respiratory failure (n = 1), hemorrhage from the pancreatic stump (n = 1), and hemorrhage from the greater omentum (n = 1). There were no significant intergroup differences related to these other complications (P > 0.9999). The patient with the port-site hernia in the E group was operated on again. Hemostasis was achieved conservatively for the hemorrhages from the pancreatic stump and greater omentum in the two patients in the T group, but both patients subsequently underwent laparoscopic surgery again to eliminate intraabdominal hematomas and wash the intra-abdominal area with saline. There were no significant intergroup differences in terms of the reoperation ratio (P > 0.9999). Late-phase complications were observed in 4 of 47 patients in the E group (port-site hernia [n = 1], onset of
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diabetes mellitus [n = 2], and pseudocyst formation [n = 1]) and in 1 of 53 patients in the T group (port-site hernia). There were no significant intergroup differences (P = 0.1841). The median postoperative hospital stay was 10 days (range, 6–76 days) in the E group and 13 days (range, 7–77 days) in the T group. The median hospital stay for the E group was significantly shorter than for the T group (P = 0.0307) (Table 3). In a subgroup analysis of oncologic outcomes in patients undergoing Lap-DP for pancreatic adenocarcinoma, total lymph node harvest and margin status did not differ significantly between the two groups (Table 3).
Discussion Laparoscopic pancreatectomy was first reported by Gagner and Pomp in 1994 (22), and since then, there has been a rapid increase in the number of papers reporting the effectiveness of this technique. Most of the reports cite reduced blood loss and shorter hospital stay as the main advantages of laparoscopic pancreatectomy (13,23– 25). More recently, a number of meta-analyses have compared Lap-DP with laparotomy in terms of surgical outcomes (8–13). All of these studies suggest that Lap-DP produces beneficial outcomes. Now that Lap-DP has become widely recognized as a well-established surgical procedure like Lap-C, it is time to consider how to educate surgeons training to perform this technique to ensure it is passed on safely. Lap-DP was first used at our hospital in January 2004. For the first 6 years, the surgeon who introduced the procedure performed all Lap-DP operations and confirmed its feasibility, safety, and efficacy (4). In January 2010, a number of more junior surgeons started performing the procedure, with the surgeon who introduced the procedure acting as a coach during surgery. This study compared the outcomes of surgery performed by an expert surgeon and by surgeons training to perform LapDP; it showed that the change in surgeons did not have a negative impact on operating times and blood loss during surgery. The study suggested that Lap-DP could be safely
Asian J Endosc Surg 7 (2014) 295–300 © 2014 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Wiley Publishing Asia Pty Ltd
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Table 3 Postoperative results of Lap-DP
Grade B or C pancreatic fistula†, n (%) Other complications, n (%) Reoperation, n (%) Late-phase complications, n (%) Median LOS, days (range) Mortality (n) Oncologic outcomes in PDAC (n) Retrieved lymph nodes, mean ± SD (n) R0 resection ratio
E group (n = 47)
T group (n = 53)
P-value
6/47 (12.8) 3/47 (6.4) 1/47 (2.1) 4/47 (8.5) 10 (6–76) 0 10 17.3 ± 10.1 80%
9/53 (16.9) 3/53 (5.7) 2/53 (3.8) 1/53 (1.9) 13 (7–77) 0 10 19.0 ± 7.8 90%
0.5886 >0.9999 >0.9999 0.1841 0.0307
0.6377 >0.9999
†According to International Study Group of Pancreatic Fistula. E group, expert surgeon group; Lap-DP, laparoscopic distal pancreatectomy; LOS, length of stay; PDAC, pancreatic ductal adenocarcinoma; T group, training surgeons group.
performed in a standardized way within the same hospital if the surgeon has acted as a laparoscopist during laparoscopic pancreatectomies and has performed Lap-C in at least 50 patients and open pancreatectomy in at least 10 patients. During laparoscopic surgery, all members of the surgical team share the same visual field. This provides a major advantage for teaching purposes compared with laparotomy. Even those not part of the surgical team can view the same visual field as the surgeon via a monitor relay, which is extremely useful for observational studies of surgery. With laparotomy, the lead surgeon monopolizes the best visual field, so there are limited opportunities for effective observational learning by surgical assistants or students. The pancreas can be very difficult to see because it is sited deep within the body, so it is extremely difficult to learn laparotomic techniques unless you are performing the surgery. Unlike laparoscopic pancreaticoduodenectomy, Lap-DP does not require specialized techniques for reconstructive surgery, so it is suited to observational study in the same way that Lap-C and laparoscopic adrenalectomy methods are. It is important to watch numerous standardized Lap-DP procedures in order to gain an understanding of the dissection and surgical procedures required. In this study, there was no negative impact on the percentage of postoperative complications occurring in the T and E groups, including pancreatic fistula. There was also no significant difference in the percentage of patients requiring reoperation. Postoperative hospital stays were significantly longer in the T group than in the E group. This may have occurred because the T-group operations were conducted by surgeons training to perform Lap-DP who may have delayed discharge in order to allow longer postoperative observation of their patients. On average, patients in the T group spent only 3 more days in the hospital than those in the E group. As
such, we do not think the difference in hospital stay reflects a failure in terms of education on patient safety. In patients with pancreatic adenocarcinoma, total lymph node harvest and margin status did not differ significantly between the two groups (Table 3). We think the results suggest that the T-group surgeons had mastered the techniques for lymph node dissection and margin-free resection. Recently published papers show that total lymph node harvest and margin status do not differ between laparoscopic pancreatectomy and laparotomy for pancreatic adenocarcinoma (9,13,23). The literature also contains reports on new surgical techniques to improve oncological curability (26,27). A laparoscope allows the visual field to be magnified ×10–15, and this magnified view may allow greater fine dissection during resection than laparotomy. This may result in resection techniques that offer greater curability. It is very useful to be able to teach surgical techniques to training surgeons using the visual field that is shared with the surgeon and the surgical assistants and that is magnified thanks to laparoscopic technology. This retrospective analysis, performed over a limited time frame, shows that teaching safe Lap-DP techniques to surgeons is reflected in stable perioperative outcomes. Prospective randomized trials should be performed to demonstrate this concept.
Acknowledgment The authors have no conflicts of interest or financial ties to disclose.
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