TECHNICAL NOTES
Transanal Endoscopic Microsurgery Colorectal Anastomosis: A Critical Step to Natural Orifice Colorectal Surgery in Humans David J. Hall, M.B.B.S., M.P.H.1 • K. Chip Farmer, F.R.A.C.S.1 Hedley S. Roth, M.B.B.S., M.P.H.1 • Satish K. Warrier, F.R.A.C.S.1, 2 1 Colorectal Surgical Unit, Alfred Health, Melbourne, Victoria, Australia 2 Division of Cancer Surgery, Peter MacCallum Cancer Institute, Melbourne, Victoria, Australia
BACKGROUND: Transanal endoscopic microsurgery is used in the surgical management of advanced rectal polyps and early rectal cancers. There are case reports of transanal endoscopic microsurgery colorectal anastomoses being performed with laparoscopic assistance in humans. METHODS: The concept of a transanal endoscopic microsurgery colorectal anastomosis without laparoscopic assistance has been discussed and trialed on animal and cadaveric specimens; however, to date, there have been no technical reports of this particular procedure in the literature. RESULTS: We present a technical note describing a transanal endoscopic microsurgery intraperitoneal colorectal anastomosis in a live human without laparoscopic assistance.
KEY WORDS: Transanal endoscopic microsurgery; Natural orifice transluminal endoscopic surgery; Neoplasia; Anastomosis; Rectal; Colorectal.
T
ransanal endoscopic microsurgery (TEM) is well established as a diagnostic and therapeutic technique in the surgical management of both ad-
Financial Disclosure: None reported. Poster presentation at the meeting of the Royal Australian College of Surgeons, Auckland, New Zealand, May 6 to 10, 2013. Correspondence: Satish K. Warrier, F.R.A.C.S., Colorectal Surgeon, Department of Colorectal Surgery, Alfred Health, Commercial Rd, Prahran 3181, Victoria, Australia. E-mail: [email protected] Dis Colon Rectum 2014; 57: 549–552 DOI: 10.1097/DCR.0000000000000104 © The ASCRS 2014 Diseases of the Colon & Rectum Volume 57: 4 (2014)
vanced polyps and select early cancers of the mid or distal rectum.1,2 The feasibility and safety of TEM surgery to perform rectosigmoid resection has been demonstrated in cadaveric as well as animal models.3 In addition, the concept of a rectosigmoid resection with an end-to-end colonic anastomosis has also been proposed in animal and cadaveric models. The advantages of a minimally invasive approach include less surgical trauma, faster recovery time, improved cosmesis, and more rapid return of normal bowel function.4,5 Natural orifice transluminal endoscopic surgery (NOTES) provides “incision”-less surgery with the additional advantages of maintaining the abdominal wall integrity.6 In the recent literature, the technique of a TEM rectosigmoid resection and end-to-end anastomosis has been demonstrated in live human cases, albeit with laparoscopic assistance. We describe a complete circumferential intraperitoneal rectosigmoid anastomosis performed on a human with no laparoscopic assistance. This procedure was performed as a salvage operation following an unintended circumferential TEM rectal resection.
TECHNICAL NOTE The indication for the procedure was excision of the rectal scar from a previous endoscopically removed rectal adenocarcinoma with unclear margins on histopathological analysis. The polyp had been excised approximately 15 cm from the anal verge, and the region had been marked with spot dye tattooing. There was no lymphovascular invasion and no perineural invasion, although the Kikuchi submucosal level was unclear. The patient received preoperative bowel preparation. Preoperative antibiotic prophylaxis was given. The area of the tattooing was diffuse and involved 3 quarters of the circumference of the right posterior position. The patient 549
550
FIGURE 1. Commencing the anastomosis. The free end of sigmoid colon is seen with rectal mucosa in the foreground.
was placed in the left lateral position. A Wolf TEM scope was used to complete the procedure. The full-thickness dissection was commenced on both sides of the rectal scar. The lines of dissection were progressed in a radial fashion but in a proximal and distal plane such that the specimen was removed as a ring of full-thickness rectosigmoid rather than the intended disc. Following resection, the specimen was removed transanally. The distal sigmoid colon with its taenia could be visualized through the endoscope (Fig. 1). Both surgeons in attendance were experienced laparoscopic colorectal surgeons with the senior surgeon (K.C.F.) Australia’s most experienced TEM specialist. A decision was made to perform a TEM intracorporeal circumferential colorectal anastomosis. The proximal colon with its accompanying distinct taenia could be seen through the endoscope. Two full-thickness figureof-8 stitches with 3-0 polydiaxone (PDS) were placed at each apex in the anatomical anterior and posterior position (Fig. 2). This divided the defect into 2 hemicircumferential areas. A continuous PDS suture was used to close the defect lying inferiorly (anatomical right). The suture
FIGURE 2. Second figure-of-8 suture. The first completed suture is seen at the 3 o’clock position with securing bead.
HALL ET AL: A SALVAGE CIRCUMFERENTIAL TEM ANASTOMOSIS
FIGURE 3. Continuous suture closing the anatomical right-sided defect (to the right of the image). The figure-of-8 stay suture bead and initial securing bead for the continuous suture can be visualized. The white arrow indicates the direction of continuous suturing.
was initially secured with a bead, and subsequent fullthickness bites were taken to ensure the inclusion of all layers of the colon and rectum. This continuous suture was secured with another bead. Several readjustments of the Wolf TEM scope were required to ensure that the operating site remained in the center of the scope's field of view. Suturing was performed from 3 o’clock to 9 o’clock as demonstrated by the direction of the arrow in Figure 3. The patient was then repositioned to the left lateral position. This was performed by removing the TEM proctoscope and drapes, rolling the patient, re-preparing and draping the patient, and reinserting the scope. Another PDS suture was used in identical fashion to close the inferior defect (anatomical left) to complete the anastomosis. The anastomosis was completed in 45 minutes. No diverting ileostomy was formed. The completed anastomosis is shown in Figure 4. The integrity of the anastomosis was visually inspected endoluminally and confirmed with an on-table
FIGURE 4. Tension applied to the completed hemicircumferential continuous suture before being secured with a bead.
Diseases of the Colon & Rectum Volume 57: 4 (2014)
FIGURE 5. On-table Gastrografin enema demonstrating anastomotic integrity with no leak demonstrated.
Gastrografin enema and x-ray image intensifier, revealing a complete anastomosis with no leak. The Gastrografin enema film is shown in Figure 5. The patient was managed postoperatively as if for a standard laparoscopic colorectal anastomosis.
FOLLOW-UP Diet was commenced on postoperative day 1. The patient was discharged day 2 after the passage of flatus and bowel movements. Outpatient follow-up at 3 weeks revealed a well patient with normal rectal function and bowel movements. Upon further outpatient follow-up at 3, 6, and 9 months, bowel movements have remained normal. Repeat rigid sigmoidoscopy on each occasion has shown a wellhealed, intact anastomosis with no signs of recurrence. Screening CT chest/abdomen/pelvis has shown no sign of distant metastatic disease, and the patient is scheduled for a colonoscopy at 1 year postprocedure.
DISCUSSION The described technical note reports an intraperitoneal rectosigmoid colorectal anastomosis performed entirely through a TEM machine. The report was performed by an experienced TEM-accredited colorectal specialist as a salvage option following full-thickness circumferential resection of the rectosigmoid junction. Continuity of the colorectal anastomosis was confirmed with a Gastrografin enema on table.
551
Transanal endoscopic microsurgery resection for neoplasia in the rectum has been well described for diagnostic or therapeutic purposes. For advanced neoplasia of the rectum, the advantage of TEM over endoscopic mucosal resection is that submucosal staging is accurate and therefore more accurately allows pathologists to predict lymph node status. Our policy at Alfred Health is to offer a TEM for early T1 rectal cancers or cancers within polyps with Kikuchi SM1 level in the absence of any other adverse prognostic features. In Kikuchi’s initial description of lymph node status, the risk of lymph node status was shown to be 0% but realistically it is 1% to 2%.7 We believe this is acceptable. Although TEM allows local excision of advanced neoplastic lesions, where full-thickness excision is necessary in the proximal rectum, it carries the risk of intraperitoneal breach, and, therefore, patients should be consented for the possibility of a laparoscopic or open salvage. In our particular case following full-thickness excision, the sigmoid colon was closely approximated to the rectum, and therefore a decision was made to perform salvage with a TEM colorectal anastomosis. The alternative would have been to perform a laparoscopic anastomosis that both surgeons are comfortable with performing. It has been demonstrated that entry into the peritoneal cavity by using TEM equipment can be performed with no adverse outcomes provided the mucosal defect is closed meticulously.8–10 Given their intention for operating within the endoluminal field, the limitations of traditional TEM instruments within the peritoneum have been noted previously.4 A further limitation for isolated TEM in performing rectosigmoid resections has been the requirement to perform a rectal end-to-end anastomosis from the endoluminal operating viewpoint.11 Because of these limitations, a purely NOTES procedure to perform a circumferential rectosigmoid resection and anastomosis has not been performed. This case highlights that an intraperitoneal colorectal anastomosis performed on a live human with the use of standard TEM instruments with no laparoscopic assistance is possible. Indeed, it may represent a critical step to NOTES colorectal surgery. Operating entirely from the endoluminal viewpoint precludes anastomotic integrity assessment with the traditional air-leak test. The authors assessed the integrity of the completed anastomosis by performing an on-table Gastrografin enema, a novel intraoperative method for the assessment of colorectal anastomosis adequacy. In describing the technique, there are a few points worth noting. First, our case is a description of an upper rectal/ rectosigmoid circumferential resection and does not represent a total mesorectal excision (TME). The latter technique, which was popularized by Heald,12 involves an extrafascial dissection of the entire mesorectum. This can be performed by open, laparoscopic, and robotic techniques. More recently, the TEM device has been used to facilitate the inferior dissection.13 We are not describing
552
this. Our technique also differs from a conventional colectomy with subsequent rectosigmoid anastomosis, because the blood supply has not been disrupted proximally, the orientation of the colon is correct, and the close approximation of resection margins means that tension is not an issue. We have not performed an ileostomy in this case because of these technical factors; however, we are not advocating such an approach for TME resections. In fact, only in carefully selected patients would we offer a low anterior resection without an ileostomy, and certainly, in the vast majority of our low anterior resections and ultralow anterior resections, we would perform a diverting ileostomy following a TME resection.
CONCLUSION This technical note describes a successfully performed intraperitoneal circumferential, full-thickness, rectal resection with colorectal anastomosis using TEM technology without laparoscopic assistance, performed by one of Australia’s most experienced TEM colorectal surgeons. This technique warrants further experience and long-term patient follow-up to determine its indications and feasibility. References 1. Allaix ME, Arezzo A, Caldart M, Festa F, Morino M. Transanal endoscopic microsurgery for rectal neoplasms: experience of 300 consecutive cases. Dis Colon Rectum. 2009;52:1831–1836. 2. Guerrieri M, Baldarelli M, de Sanctis A, Campagnacci R, Rimini M, Lezoche E. Treatment of rectal adenomas by transanal endoscopic microsurgery: 15 years’ experience. Surg Endosc. 2010;24:445–449.
HALL ET AL: A SALVAGE CIRCUMFERENTIAL TEM ANASTOMOSIS
3. Bhattacharjee HK, Buess GF, Becerra Garcia FC, et al. A novel single-port technique for transanal rectosigmoid resection and colorectal anastomosis on an ex vivo experimental model. Surg Endosc. 2011;25:1844–1857. 4. Knol J, D’Hondt M, Dozois EJ, Vanden Boer J, Malisse P. Laparoscopic-assisted sigmoidectomy with transanal specimen extraction: a bridge to NOTES? Tech Coloproctol. 2009;13:65–68. 5. Veldkamp R, Kugry E, Hop W, et al. Laparoscopic surgery versus open surgery for colon cancer: short term outcomes of a randomised trial. Lancet Oncol. 2005;6:477–484. 6. Sylla P, Rattner DW, Delgado S, Lacy AM. NOTES transanal rectal cancer resection using transanal endoscopic microsurgery and laparoscopic assistance. Surg Endosc. 2010;24:1205–1210. 7. Kikuchi R, Takano M, Takagi K, et al. Management of early invasive colorectal cancer. Risk of recurrence and clinical guidelines. Dis Colon Rectum. 1995;38:1286–1295. 8. Tsai BM, Finne CO, Nordenstam JF, Christoforidis D, Madoff RD, Mellgren A. Transanal endoscopic microsurgery resection of rectal tumors: outcomes and recommendations. Dis Colon Rectum. 2010;53:16–23. 9. Cataldo PA, O’Brien S, Osler T. Transanal endoscopic microsurgery: a prospective evaluation of functional results. Dis Colon Rectum. 2005;48:1366–1371. 10. Whiteford MH, Denk PM, Swanström LL. Feasibility of radical sigmoid colectomy performed as natural orifice translumenal endoscopic surgery (NOTES) using transanal endoscopic microsurgery. Surg Endosc. 2007;21:1870–1874. 11. Fajardo AD, Hunt SR, Fleshman JW, Mutch MG. Transanal single-port low anterior resection in a cadaver model. Surg Endosc. 2010;24:1765–1765. 12. Heald RJ, Ryall RD. Recurrence and survival after total mesorectal excision for rectal cancer. Lancet. 1986;28:1479–1482. 13. Rouanet P, Mourregot A, Azar CC, et al. Transanal endoscopic proctectomy: an innovative procedure for difficult resection of rectal tumors in men with narrow pelvis. Dis Colon Rectum. 2013;56:408–415.
Transanal Endoscopic Microsurgery Colorectal Anastomosis: A Critical Step to Natural Orifice Colorectal Surgery in Humans David J. Hall, M.B.B.S., M.P.H.1 • K. Chip Farmer, F.R.A.C.S.1 Hedley S. Roth, M.B.B.S., M.P.H.1 • Satish K. Warrier, F.R.A.C.S.1, 2 1 Colorectal Surgical Unit, Alfred Health, Melbourne, Victoria, Australia 2 Division of Cancer Surgery, Peter MacCallum Cancer Institute, Melbourne, Victoria, Australia
BACKGROUND: Transanal endoscopic microsurgery is used in the surgical management of advanced rectal polyps and early rectal cancers. There are case reports of transanal endoscopic microsurgery colorectal anastomoses being performed with laparoscopic assistance in humans. METHODS: The concept of a transanal endoscopic microsurgery colorectal anastomosis without laparoscopic assistance has been discussed and trialed on animal and cadaveric specimens; however, to date, there have been no technical reports of this particular procedure in the literature. RESULTS: We present a technical note describing a transanal endoscopic microsurgery intraperitoneal colorectal anastomosis in a live human without laparoscopic assistance.
KEY WORDS: Transanal endoscopic microsurgery; Natural orifice transluminal endoscopic surgery; Neoplasia; Anastomosis; Rectal; Colorectal.
T
ransanal endoscopic microsurgery (TEM) is well established as a diagnostic and therapeutic technique in the surgical management of both ad-
Financial Disclosure: None reported. Poster presentation at the meeting of the Royal Australian College of Surgeons, Auckland, New Zealand, May 6 to 10, 2013. Correspondence: Satish K. Warrier, F.R.A.C.S., Colorectal Surgeon, Department of Colorectal Surgery, Alfred Health, Commercial Rd, Prahran 3181, Victoria, Australia. E-mail: [email protected] Dis Colon Rectum 2014; 57: 549–552 DOI: 10.1097/DCR.0000000000000104 © The ASCRS 2014 Diseases of the Colon & Rectum Volume 57: 4 (2014)
vanced polyps and select early cancers of the mid or distal rectum.1,2 The feasibility and safety of TEM surgery to perform rectosigmoid resection has been demonstrated in cadaveric as well as animal models.3 In addition, the concept of a rectosigmoid resection with an end-to-end colonic anastomosis has also been proposed in animal and cadaveric models. The advantages of a minimally invasive approach include less surgical trauma, faster recovery time, improved cosmesis, and more rapid return of normal bowel function.4,5 Natural orifice transluminal endoscopic surgery (NOTES) provides “incision”-less surgery with the additional advantages of maintaining the abdominal wall integrity.6 In the recent literature, the technique of a TEM rectosigmoid resection and end-to-end anastomosis has been demonstrated in live human cases, albeit with laparoscopic assistance. We describe a complete circumferential intraperitoneal rectosigmoid anastomosis performed on a human with no laparoscopic assistance. This procedure was performed as a salvage operation following an unintended circumferential TEM rectal resection.
TECHNICAL NOTE The indication for the procedure was excision of the rectal scar from a previous endoscopically removed rectal adenocarcinoma with unclear margins on histopathological analysis. The polyp had been excised approximately 15 cm from the anal verge, and the region had been marked with spot dye tattooing. There was no lymphovascular invasion and no perineural invasion, although the Kikuchi submucosal level was unclear. The patient received preoperative bowel preparation. Preoperative antibiotic prophylaxis was given. The area of the tattooing was diffuse and involved 3 quarters of the circumference of the right posterior position. The patient 549
550
FIGURE 1. Commencing the anastomosis. The free end of sigmoid colon is seen with rectal mucosa in the foreground.
was placed in the left lateral position. A Wolf TEM scope was used to complete the procedure. The full-thickness dissection was commenced on both sides of the rectal scar. The lines of dissection were progressed in a radial fashion but in a proximal and distal plane such that the specimen was removed as a ring of full-thickness rectosigmoid rather than the intended disc. Following resection, the specimen was removed transanally. The distal sigmoid colon with its taenia could be visualized through the endoscope (Fig. 1). Both surgeons in attendance were experienced laparoscopic colorectal surgeons with the senior surgeon (K.C.F.) Australia’s most experienced TEM specialist. A decision was made to perform a TEM intracorporeal circumferential colorectal anastomosis. The proximal colon with its accompanying distinct taenia could be seen through the endoscope. Two full-thickness figureof-8 stitches with 3-0 polydiaxone (PDS) were placed at each apex in the anatomical anterior and posterior position (Fig. 2). This divided the defect into 2 hemicircumferential areas. A continuous PDS suture was used to close the defect lying inferiorly (anatomical right). The suture
FIGURE 2. Second figure-of-8 suture. The first completed suture is seen at the 3 o’clock position with securing bead.
HALL ET AL: A SALVAGE CIRCUMFERENTIAL TEM ANASTOMOSIS
FIGURE 3. Continuous suture closing the anatomical right-sided defect (to the right of the image). The figure-of-8 stay suture bead and initial securing bead for the continuous suture can be visualized. The white arrow indicates the direction of continuous suturing.
was initially secured with a bead, and subsequent fullthickness bites were taken to ensure the inclusion of all layers of the colon and rectum. This continuous suture was secured with another bead. Several readjustments of the Wolf TEM scope were required to ensure that the operating site remained in the center of the scope's field of view. Suturing was performed from 3 o’clock to 9 o’clock as demonstrated by the direction of the arrow in Figure 3. The patient was then repositioned to the left lateral position. This was performed by removing the TEM proctoscope and drapes, rolling the patient, re-preparing and draping the patient, and reinserting the scope. Another PDS suture was used in identical fashion to close the inferior defect (anatomical left) to complete the anastomosis. The anastomosis was completed in 45 minutes. No diverting ileostomy was formed. The completed anastomosis is shown in Figure 4. The integrity of the anastomosis was visually inspected endoluminally and confirmed with an on-table
FIGURE 4. Tension applied to the completed hemicircumferential continuous suture before being secured with a bead.
Diseases of the Colon & Rectum Volume 57: 4 (2014)
FIGURE 5. On-table Gastrografin enema demonstrating anastomotic integrity with no leak demonstrated.
Gastrografin enema and x-ray image intensifier, revealing a complete anastomosis with no leak. The Gastrografin enema film is shown in Figure 5. The patient was managed postoperatively as if for a standard laparoscopic colorectal anastomosis.
FOLLOW-UP Diet was commenced on postoperative day 1. The patient was discharged day 2 after the passage of flatus and bowel movements. Outpatient follow-up at 3 weeks revealed a well patient with normal rectal function and bowel movements. Upon further outpatient follow-up at 3, 6, and 9 months, bowel movements have remained normal. Repeat rigid sigmoidoscopy on each occasion has shown a wellhealed, intact anastomosis with no signs of recurrence. Screening CT chest/abdomen/pelvis has shown no sign of distant metastatic disease, and the patient is scheduled for a colonoscopy at 1 year postprocedure.
DISCUSSION The described technical note reports an intraperitoneal rectosigmoid colorectal anastomosis performed entirely through a TEM machine. The report was performed by an experienced TEM-accredited colorectal specialist as a salvage option following full-thickness circumferential resection of the rectosigmoid junction. Continuity of the colorectal anastomosis was confirmed with a Gastrografin enema on table.
551
Transanal endoscopic microsurgery resection for neoplasia in the rectum has been well described for diagnostic or therapeutic purposes. For advanced neoplasia of the rectum, the advantage of TEM over endoscopic mucosal resection is that submucosal staging is accurate and therefore more accurately allows pathologists to predict lymph node status. Our policy at Alfred Health is to offer a TEM for early T1 rectal cancers or cancers within polyps with Kikuchi SM1 level in the absence of any other adverse prognostic features. In Kikuchi’s initial description of lymph node status, the risk of lymph node status was shown to be 0% but realistically it is 1% to 2%.7 We believe this is acceptable. Although TEM allows local excision of advanced neoplastic lesions, where full-thickness excision is necessary in the proximal rectum, it carries the risk of intraperitoneal breach, and, therefore, patients should be consented for the possibility of a laparoscopic or open salvage. In our particular case following full-thickness excision, the sigmoid colon was closely approximated to the rectum, and therefore a decision was made to perform salvage with a TEM colorectal anastomosis. The alternative would have been to perform a laparoscopic anastomosis that both surgeons are comfortable with performing. It has been demonstrated that entry into the peritoneal cavity by using TEM equipment can be performed with no adverse outcomes provided the mucosal defect is closed meticulously.8–10 Given their intention for operating within the endoluminal field, the limitations of traditional TEM instruments within the peritoneum have been noted previously.4 A further limitation for isolated TEM in performing rectosigmoid resections has been the requirement to perform a rectal end-to-end anastomosis from the endoluminal operating viewpoint.11 Because of these limitations, a purely NOTES procedure to perform a circumferential rectosigmoid resection and anastomosis has not been performed. This case highlights that an intraperitoneal colorectal anastomosis performed on a live human with the use of standard TEM instruments with no laparoscopic assistance is possible. Indeed, it may represent a critical step to NOTES colorectal surgery. Operating entirely from the endoluminal viewpoint precludes anastomotic integrity assessment with the traditional air-leak test. The authors assessed the integrity of the completed anastomosis by performing an on-table Gastrografin enema, a novel intraoperative method for the assessment of colorectal anastomosis adequacy. In describing the technique, there are a few points worth noting. First, our case is a description of an upper rectal/ rectosigmoid circumferential resection and does not represent a total mesorectal excision (TME). The latter technique, which was popularized by Heald,12 involves an extrafascial dissection of the entire mesorectum. This can be performed by open, laparoscopic, and robotic techniques. More recently, the TEM device has been used to facilitate the inferior dissection.13 We are not describing
552
this. Our technique also differs from a conventional colectomy with subsequent rectosigmoid anastomosis, because the blood supply has not been disrupted proximally, the orientation of the colon is correct, and the close approximation of resection margins means that tension is not an issue. We have not performed an ileostomy in this case because of these technical factors; however, we are not advocating such an approach for TME resections. In fact, only in carefully selected patients would we offer a low anterior resection without an ileostomy, and certainly, in the vast majority of our low anterior resections and ultralow anterior resections, we would perform a diverting ileostomy following a TME resection.
CONCLUSION This technical note describes a successfully performed intraperitoneal circumferential, full-thickness, rectal resection with colorectal anastomosis using TEM technology without laparoscopic assistance, performed by one of Australia’s most experienced TEM colorectal surgeons. This technique warrants further experience and long-term patient follow-up to determine its indications and feasibility. References 1. Allaix ME, Arezzo A, Caldart M, Festa F, Morino M. Transanal endoscopic microsurgery for rectal neoplasms: experience of 300 consecutive cases. Dis Colon Rectum. 2009;52:1831–1836. 2. Guerrieri M, Baldarelli M, de Sanctis A, Campagnacci R, Rimini M, Lezoche E. Treatment of rectal adenomas by transanal endoscopic microsurgery: 15 years’ experience. Surg Endosc. 2010;24:445–449.
HALL ET AL: A SALVAGE CIRCUMFERENTIAL TEM ANASTOMOSIS
3. Bhattacharjee HK, Buess GF, Becerra Garcia FC, et al. A novel single-port technique for transanal rectosigmoid resection and colorectal anastomosis on an ex vivo experimental model. Surg Endosc. 2011;25:1844–1857. 4. Knol J, D’Hondt M, Dozois EJ, Vanden Boer J, Malisse P. Laparoscopic-assisted sigmoidectomy with transanal specimen extraction: a bridge to NOTES? Tech Coloproctol. 2009;13:65–68. 5. Veldkamp R, Kugry E, Hop W, et al. Laparoscopic surgery versus open surgery for colon cancer: short term outcomes of a randomised trial. Lancet Oncol. 2005;6:477–484. 6. Sylla P, Rattner DW, Delgado S, Lacy AM. NOTES transanal rectal cancer resection using transanal endoscopic microsurgery and laparoscopic assistance. Surg Endosc. 2010;24:1205–1210. 7. Kikuchi R, Takano M, Takagi K, et al. Management of early invasive colorectal cancer. Risk of recurrence and clinical guidelines. Dis Colon Rectum. 1995;38:1286–1295. 8. Tsai BM, Finne CO, Nordenstam JF, Christoforidis D, Madoff RD, Mellgren A. Transanal endoscopic microsurgery resection of rectal tumors: outcomes and recommendations. Dis Colon Rectum. 2010;53:16–23. 9. Cataldo PA, O’Brien S, Osler T. Transanal endoscopic microsurgery: a prospective evaluation of functional results. Dis Colon Rectum. 2005;48:1366–1371. 10. Whiteford MH, Denk PM, Swanström LL. Feasibility of radical sigmoid colectomy performed as natural orifice translumenal endoscopic surgery (NOTES) using transanal endoscopic microsurgery. Surg Endosc. 2007;21:1870–1874. 11. Fajardo AD, Hunt SR, Fleshman JW, Mutch MG. Transanal single-port low anterior resection in a cadaver model. Surg Endosc. 2010;24:1765–1765. 12. Heald RJ, Ryall RD. Recurrence and survival after total mesorectal excision for rectal cancer. Lancet. 1986;28:1479–1482. 13. Rouanet P, Mourregot A, Azar CC, et al. Transanal endoscopic proctectomy: an innovative procedure for difficult resection of rectal tumors in men with narrow pelvis. Dis Colon Rectum. 2013;56:408–415.
