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Intraductal papillary mucinous neoplasm of the pancreas, one manifestation of a more systemic disease? Alexandra M. Roch, M.D., M.S.a, Carlo Maria Rosati, M.D.a, Jessica L. Cioffi, M.D.a, Eugene P. Ceppa, M.D.a, John M. DeWitt, M.D.b, Mohammad A. Al-Haddad, M.D.c, Michael G. House, M.D.a, Nicholas J. Zyromski, M.D.a, Attila Nakeeb, M.D.a, C. Max Schmidt, M.D., Ph.D., M.B.A.a,* a
Department of Surgery, Indiana University School of Medicine, 980 West Walnut Street C522, Indianapolis, IN, 46202, USA; bDivision of Gastroenterology, Department of Medicine, Indiana University Hospital, Indianapolis, IN, USA; cDigestive Disease Institute, Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates KEYWORDS: Intraductal papillary mucinous neoplasm; Extrapancreatic malignancies; Autoimmune diseases; Incidence
Abstract BACKGROUND: Several studies have demonstrated a high prevalence of extrapancreatic malignancies, and an association with autoimmune pancreatitis in patients with intraductal papillary mucinous neoplasm (IPMN). We hypothesized that IPMNs were associated with an increase rate of systemic diseases. METHODS: From 1996 to 2013, a retrospective analysis of a prospectively collected database was performed and supplemented with electronic medical charts review. RESULTS: Two hundred twenty extrapancreatic malignancies were found in 185 patients (22%) compared with expected 5% in the general population. Colorectal, lung, and renal cell carcinoma had significant observed/expected ratios (P , .0001). One hundred ten synchronous autoimmune diseases were found in 96 patients (11%). Systemic lupus erythematosus, rheumatoid arthritis, and inflammatory bowel disease showed statistically significant observed/expected ratios (P , .0001, .01, and ,.0001, respectively). There was no impact of immunosuppressive treatment on the IPMN subtype and malignancy rate. CONCLUSIONS: IPMN are associated with surprisingly high rates of autoimmune diseases suggesting that IPMN might be 1 manifestation of a more systemic disease. Ó 2016 Elsevier Inc. All rights reserved.
There were no relevant financial relationships or any sources of support in the form of grants, equipment, or drugs. The authors declare no conflicts of interest. This article has been accepted for oral presentation at the 2015 Midwest Surgical Association Meeting in Lake Geneva, WI, on July 27, 2015 * Corresponding author. Tel.: 11-317-278-8349; fax: 11-317-278-4897. E-mail address: [email protected]
Manuscript received July 14, 2015; revised manuscript December 21, 2015 0002-9610/$ - see front matter Ó 2016 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.amjsurg.2015.12.009
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In 1982, Ohashi et al1 described 4 cases of what he called ‘‘mucin-producing cancer’’, a disease affecting the main pancreatic duct and producing excessive quantities of mucus, thereby, distending the pancreatic ductal system. This type of pancreatic tumor, later in 1996 named intraductal papillary mucinous neoplasm (IPMN)2 was considered a rare entity at the time but is now believed to account for up to 70% of all cystic neoplasms of the pancreas.3 Reasons for the ‘‘IPMN epidemic’’ are unknown, but likely result from increased awareness by physicians, and recognition/detection with enhanced imaging study modalities. IPMNs are wellestablished precancerous pancreatic lesions.4,5 In addition, one of the most surprising characteristics of IPMN is the higher risk of developing extrapancreatic malignancies than patients with other pancreatic disorders such as ductal pancreatic adenocarcinoma and mucinous cystic neoplasm, or than the general population.6,7 Similarly, an association between IPMN and a more diffuse pancreatic diseasedautoimmune pancreatitisdhas been described recently in case reports and small surgical series.7–12 As IPMN and autoimmune pancreatitis are both relatively rare diseases, it is remarkable to find them coexisting in patients, although the relationship is poorly understood. In most of these cases, autoimmune pancreatitis lesions (lymphoplasmacytic and immunoglobulin G4 [IgG4] positive plasma cells infiltration with fibrosis) were confined to the periductal area in the vicinity of IPMN,10 but in rare cases lesions of autoimmune pancreatitis were detected distant to IPMN, involving the entire pancreatic gland with occasional extension to peripancreatic lymph nodes.9 As autoimmune pancreatitis lesions have been described preceding and distant from the IPMN, autoimmune pancreatitis may develop as an inflammatory reaction against IPMN. Conversely, the gradual decrease of serum IgG4 levels after IPMN surgical resection may lead to speculate that IPMN is a predisposing factor for the autoimmune disease.9 Considering the associations with cancer and autoimmune pancreatitis, we hypothesized that IPMN were associated with an increased rate of systemic diseases, especially autoimmune diseases.
Methods Patient selection From 1996 to 2013, data of all patients treated or followed for pancreatic cystic disease at a single academic institution were prospectively collected in a database. For the purpose of this study, the database was supplemented by electronic medical records review and retrospectively analyzed. Data were compiled and reported in strict compliance with patient confidentiality protocols set forth by Indiana University School of Medicine’s Institutional Review Board.
Only patients with diagnosis of IPMN were included in this study. Diagnosis of IPMN was confirmed on pathology of the specimen in patients who underwent surgical resection (indicated by the presence of Sendai criteria4 and/or 2012 updated International Consensus Guidelines5 criteria) as an intraductal proliferation of tall, columnar, mucin producing cells, arising from the main pancreatic duct and/or a branch duct, with/without papillary projections, and without ovarian-type stroma.5 In patients who underwent primary surveillance only, IPMN was diagnosed on imaging studies (computed tomography, magnetic resonance imaging/magnetic resonance cholangiopancreatography), endoscopic studies (endoscopic ultrasound, endoscopic retrograde cholangiopancreatography, pancreatic ductoscopy), cyst fluid carcinoembryonic antigen, kirsten rat sarcoma viral oncogene homolog, guanine nucleotide binding protein, alpha stimulating mutations, and/or cytology (based on fine needle aspiration of pancreatic fluid collected during endoscopic ultrasound and in select cases via ductal lavage on endoscopic retrograde cholangiopancreatography or directed biopsies via pancreatic ductoscopy). Patients with incomplete pathological data or doubtful diagnosis of IPMN were excluded.
Parameters assessed IPMNs were also classified into branch duct (BD)-IPMN or main duct (MD)-involved IPMN based on gross and microscopic histologic findings. BD-IPMN was defined as single/cluster or multiple pancreatic ‘‘cysts’’ 5 mm or more communicating with the main pancreatic duct (branch ducts). MD involvement was defined, according to the 2012 International Consensus Guidelines5 as a segmental or diffuse main pancreatic duct dilation of 5 mm or more (without any non-IPMN cause of obstruction). The presence of malignancy as defined by the most recent World Health Organization classification (invasive carcinoma) and the degree of dysplasia for nonmalignant lesions (low-grade dysplasia, moderate-grade dysplasia, and high-grade dysplasiadformerly carcinoma in situ)13 were assessed on final pathologic examination of the surgical specimen. Patients were considered symptomatic of their IPMN when they presented with symptoms/signs/conditions associated with pancreatic disease, including abdominal pain (typically epigastric or right upper quadrant pain radiating to the back), nausea/vomiting, obstructive jaundice, acute pancreatitis (or recurrent episodes of acute pancreatitis), pancreatic exocrine (steatorrhea, weight loss, malnutrition), and endocrine (glucose intolerance, prediabetes, diabetes) insufficiency.
Systemic diseases Incidence was defined according to the National Institute of Health as the number of new cancers/diseases of a
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specific site/type occurring in a specified population during a year, usually expressed as the number of cancers per 100,000 persons at risk.14 Diagnosis of extrapancreatic malignancy was based on corresponding clinical symptoms/ signs/conditions, with or without elevated tumor markers, and confirmed by biopsy or pathology of a surgical specimen. The incidence of extrapancreatic cancers in the general population was estimated by National Cancer Institute statistics, especially the Annual Report to the Nation on the Status of Cancer15 (provides an update on the trends in cancer incidence and death rates in the United States), Surveillance Epidemiology and End Results program cancer statistics review16 (provides cancer incidence, mortality, and survival data) and US cancer statistics for cancer incidence and mortality17 (provides the most comprehensive federal data available on state-specific cancer incidence rates). Diagnosis of autoimmune disease was made by a physician specialized in the field (rheumatologist, dermatologist, gastroenterologist, endocrinologist.), based on specific symptoms/signs/conditions and elevated tumor markers (autoantibodies). National incidence data were difficult to obtain because onset of autoimmune diseases may be difficult to determine (nonspecific symptoms/ signs). Estimation of the incidence of those diseases was based on National Medical Societies data (American College of Rheumatology, American Gastroenterology Association) and on Centers for Disease Control and Prevention reports.18 When the estimates range was wide, the highest found incidence was used in this study.
Statistical analysis Data compilation was performed with Microsoft Excel 2011 (Redmond, WA). Analyses were carried out with Graph Pad Prism (Graph Pad Software, Inc, La Jolla, CA). Descriptive statistics for continuous data included median, mean, range, and percentage. Subgroup comparisons of categorical data used Fisher’s exact test. Student t test compared continuous variables. The expected number of extrapancreatic malignancies and autoimmune diseases was calculated using age-standardized data on the incidence in the United States for the study period, obtained as described previously. The observed number of patients developing extrapancreatic malignancies and autoimmune diseases was compared with the expected theoretical distribution based on the literature review using Chi-square test. Statistical significance was defined at P , .05.
Results Population characteristics From 1996 to 2012, 1,300 patients were treated for pancreatic cystic disease at a single academic institution and subsequently entered into the prospective Indiana University Pancreatic Cyst database. Of those 1,300
3 patients, 841 were diagnosed with IPMN and had complete data, making them eligible for this study. Three hundred forty-one patients underwent surgical resection of their IPMN, indicated by the presence of Sendai criteria and/or 2012 updated International Consensus Guidelines criteria, whereas 500 patients underwent primary surveillance only. Mean age at diagnosis was 68 years 6 12 (range 20 to 97) with a gender ratio of 1.5 (333 men and 508 women).
Pathology Based on surgical specimen pathology for resected patients and on imaging and cytology for followed patients, 571 patients were identified with BD-IPMN, whereas 270 patients had a main pancreatic duct-involved IPMN (MD-IPMN and mixed-type-IPMN). Eighty-six patients were classified as invasive IPMN. The remaining 755 nonmalignant IPMN included 720 low/moderate dysplasia IPMN and a 35 high-grade dysplasia IPMN.
Association of intraductal papillary mucinous neoplasm with extrapancreatic malignancies Two hundred twenty extrapancreatic malignancies were found in 185 patients (22%). Similar results were found as in previous surgical series and reviews. Comparison of the observed to expected frequencies for all cancer types, colorectal carcinoma, renal cell carcinoma, and lung carcinoma reached statistical significant difference (22% vs 4.2%, 3.1% vs .35%, 1.7% vs .1%, and 1.7% vs .13%; P , .0001 for all comparisons). Furthermore, there was no difference in the incidence of extrapancreatic malignancies between BD-IPMN and MD-involved IPMN (21.7% vs 22.6%, P 5 .79), and between malignant and nonmalignant IPMN (22.1% vs 23.3%, P 5 .89).
Association of intraductal papillary mucinous neoplasm with autoimmune diseases Incidence of autoimmune diseases. One hundred ten autoimmune diseases were found in 96 patients (11.4%). The 3 most frequent autoimmune diseases were inflammatory bowel diseases (1.8%), rheumatoid arthritis (1.4%), and systemic lupus erythematosus (.7%). The complete distribution of autoimmune diseases is provided in Fig. 1. Comparison of observed/expected frequencies for those diseases yielded statistically significant differences (inflammatory bowel diseases 1.8% vs .3%, P , .0001; rheumatoid arthritis 1.4% vs .7%, P 5 .014; systemic lupus erythematosus .7% vs .06%, P , .0001). Patients with IPMN and associated autoimmune disease were more likely asymptomatic, and had more BD-IPMM, resulting in lower rates of IPMN malignancy and invasiveness. Those results are summarized in Table 1.
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Figure 1 Distribution and incidence of autoimmune diseases in patients with IPMN (n 5 96). IPMN: intraductal papillary mucinous neoplasm. *Statistically significant observed/expected ratios (P , .05).
Timing of diagnosis. When we analyzed the timeline of IPMN and autoimmune disease diagnosis, 88% of patients had their autoimmune disease diagnosed before the diagnosis of IPMN, usually several years before (range 2 months to 40 years). Only 12% had a diagnosis of IPMN 1st and subsequent diagnosis of autoimmune disease within a range of 2 months to 6 years. When the incidence of autoimmune disease was compared between patients who were exclusively followed (n 5 500) and patients operated on (n 5 341), the difference did not reach statistical
Table 1 Characteristics of IPMN when associated with autoimmune disease
IPMN with autoimmune disease (n 5 96)
IPMN without autoimmune disease (n 5 745)
Symptomatic BD-IPMN MD-involved IPMN Malignant IPMN*
47 74 22 3
539 497 248 83
(49%) (77%) (23%) (3%)
(72%) (67%) (33%) (11%)
P value ,.0001† .048† .011†
BD 5 branch duct; IPMN 5 intraductal papillary mucinous neoplasm; MD 5 main duct. *Malignancy was defined according to the 2010 WHO classification as invasive IPMN. † Statistically significant P value (,.05).
significance (13% in the surveillance group vs 9% in the surgery group, P 5 .06). Sub analysis of patients with symptomatic intraductal papillary mucinous neoplasm. To avoid type I error, we separately analyzed patients symptomatic of their IPMN (n 5 586 patients). Of those 586 patients, 47 presented an autoimmune disease. When the observed/expected frequencies of autoimmune diseases in this subpopulation were compared, similar statistically significant difference as in our overall population was found for inflammatory bowel diseases, rheumatoid arthritis, and systemic lupus erythematosus (1% vs .3%, 1.4% vs .7% and .3% vs .06%, P 5 .002, .05, and .005, respectively). Subanalysis of patients according to their management. The incidence of autoimmune diseases was comparable between the patients who underwent surgery and those who underwent surveillance (9% vs 13%, P 5 .06). Of the 341 patients who underwent surgical resection and, therefore, had a diagnosis of IPMN on the gold standard surgical pathology, 30 had an autoimmune disease. When we compared the observed/expected frequencies of autoimmune diseases in these patients with confirmed diagnosis of IPMN, there was a statistically significant increased incidence of inflammatory bowel disease and systemic lupus erythematosus in patients with IPMN (.9% vs .3% and .3% vs .006%, P 5 .04, and .005, respectively). It was
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not significant for rheumatoid arthritis (1.2% vs .7%, P 5 .16). Similarly, of the 500 patients who were followed, 66 presented an autoimmune disease. The observed/expected frequencies comparison for inflammatory bowel disease, rheumatoid arthritis, and systemic lupus erythematosus showed statistically significant difference (2% vs .3%, 1.6% vs .7%, and 1% vs .006%, P , .0001, .004, and ,.0001). Influence of immunosuppressive therapy. Of the 96 patients with associated autoimmune disease, 33 (34%) only had an immunosuppressive treatment. The use of immunosuppressive treatment did not influence the type of IPMN (BD-IPMN 82% vs 74%; MD-involved IPMN 18% vs 26%, P 5 .61), the rate of malignant or invasive IPMN (3% vs 6% and 3% vs 3%, P 5 .66 and z1, respectively).
Comments In this single institution series, we report a statistically significant association of IPMN of the pancreas with systemic autoimmune diseases, especially inflammatory bowel disease, rheumatoid arthritis, and systemic lupus erythematosus. Several surgical series and reviews have previously described an association of IPMN with systemic diseases, more specifically extrapancreatic malignancies in 9% to 52% of patients.6,7 This association was described as early as 1999 by Sugiyama et al19 and was initially thought to be incidental or biased by closer surveillance in patients with IPMN but since then some authors have reported that patients with IPMN would more likely die of an extrapancreatic malignancy than from the IPMN itself.20 This bias of incidental diagnosis during close follow-up was still a possibility in our study. However, when we subanalyzed only patients with symptomatic IPMN, we found a similar association with autoimmune diseases. Similarly, patients who underwent surveillance only and therefore had an increased number of clinic visits and cross sectional imaging studies had an incidence of autoimmune diseases that was comparable to surgical patients. The association of IPMN with autoimmune disease has been limited thus far to autoimmune pancreatitis. Several case reports and small series have concluded in an association between those 2 diseases,8–12 although no large-scale study has analyzed this relationship. One recent pathological study from the United Kingdom described 2 cases where IPMN was actually associated with a more systemic IgG4 disease, involving autoimmune pancreatitis and extrapancreatic involvement, namely pulmonary nodules and enlarged lymph nodes.12 Two case reports described the diagnosis of IPMN in patients with sclerosing cholangitis and retroperitoneal fibrosis, leading the authors to hypothesize that IPMN may develop in individuals with predisposing condition for IgG4–related disease. Our study presents several limitations. It is a single institution series
5 spanning over more than 16 years. Patients with IPMN include both patients who underwent surgical resection and followed patients. In the surveillance population, the diagnosis of IPMN and degree of dysplasia is made by imaging studies and cytology, and therefore is not equivalent to the gold standard surgical pathology. Fifty-nine percent of the patients with IPMN were diagnosed by methods other than definitive pathology of the surgical specimen. They were diagnosed by several methods including imaging studies, endoscopic studies, cyst fluid analysis, and were managed by. Some patients may have been misdiagnosed with IPMN and therefore may compromise most of the study patients. However, subanalysis of patients according to the method of diagnosis would be artificial as patients are diagnosed with IPMN based on a body of arguments from all those modalities and not one examination only. Finally, the expected incidences of both extrapancreatic malignancies and autoimmune diseases are based on national literature data and may not be similar to the incidence in Midwest patients.
Conclusion This study is, to our knowledge, the first to describe an association between IPMN of the pancreas and systemic autoimmune diseases. Larger multi-institutional public health studies will be needed to confirm this novel association between IPMN and autoimmune disease and to assess the utility of screening patients with autoimmune diseases for IPMN. If this association is confirmed by epidemiological studies, translational research will be required to understand the underlying mechanisms of this relationship.
References 1. Ohashi K, Murakami Y, Maruyama M, et al. Four cases of mucous secreting pancreatic cancer. Prog Dig Endosc 1982;20:348–51. 2. Kloppel G, Solcia E, Longnecker DS, et al. Histological typing of tumors of the exocrine pancreas. In: World Health Organization, ed. International Classification of Tumors. 2nd ed. Berlin: Springer; 1996. p. 11–20. 3. Werner J, Fritz S, Bu¨chler MW. Intraductal papillary mucinous neoplasms of the pancreas: a surgical disease. Nat Rev Gastroenterol Hepatol 2012;9:253–9. 4. Tanaka M, Chari S, Adsay V, et al. International consensus guidelines for management of intraductal papillary mucinous neoplasms and mucinous cystic neoplasms of the pancreas. Pancreatology 2006;6: 17–32. 5. Tanaka M, Fernandez del Castillo C, Adsay V, et al. International consensus guidelines 2012 for the management of IPMN and MCN of the pancreas. Pancreatology 2012;12:183–97. 6. Pugliese L, Keskin M, Maisonneuve P, et al. Increased incidence of extrapancreatic neoplasms in patients with IPMN: fact or fiction? A critical systematic review. Pancreatology 2015;15:209–16. 7. Baiocchi GL, Molfino S, Frittoli B, et al. Increased risk of second malignancy in pancreatic intraductal papillary mucinous tumors: review of the literature. World J Gastroenterol 2015;21:7313–9. 8. Naitoh I, Nakazawa T, Notohara K, et al. Intraductal papillary mucinous neoplasm associated with autoimmune pancreatitis. Pancreas 2013;42:552–3.
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9. Vacquero EC, Salcedo MT, Cuatrecases M, et al. Autoimmune pancreatitis type-1 associated with intraduct papillary mucinous neoplasm: report of two cases. Pancreatology 2014;14:316–8. 10. Urata T, Naito Y, Izumi Y, et al. Localized type 1 autoimmune pancreatitis superimposed upon preexisting intraductal papillary mucinous neoplasms. World J Gastroenterol 2013;19:9127–32. 11. Tabata T, Kamisawa T, Hara S, et al. Intraductal papillary mucinous neoplasm of the pancreas and IgG4-related disease: a coincidental association. Pancreatology 2013;13:379–83. 12. Bateman AC, Culver EL, Sommerlad M, et al. Intraduct papillary mucinous neoplasm of the pancreas: a tumour linked with IgG4related disease? J Clin Pathol 2013;66:671–5. 13. Adsay NV, Fukushima N, Furukawa T, et al. Intraductal neoplasm of the pancreas. In: Bosman FT, Carneiro F, Hruban RH, et al., eds. WHO classification of tumors of the digestive system. Lyon: WHO press; 2010. p. 304–P313. 14. NCI Dictionary of cancer Terms. Available at: http://www.cancer.gov/ dictionary. Accessed July 13, 2015. 15. Kohler BA, Sherman RL, Howlader N, et al. Annual report to the nation on the status of cancer, 1975-2011, featuring incidence of breast cancer subtypes by race/ethnicity, poverty, and state. J Natl Cancer Inst 2015;107:1–25. 16. Howlader N, Noone AM, Krapcho M, et al. SEER Cancer Statistics Review, 1975-2012. Bethesda, MD: National Cancer Institute. Available at: http://seer.cancer.gov/csr/1975_2012/. Based on November 2014 SEER data submission, posted to the SEER web site, April 2015. Accessed July 13, 2015. 17. American Cancer Society. Cancer Facts & Figures 2015. Atlanta: American Cancer Society; 2015 Available at: http://www.cancer.org/ acs/groups/content/@editorial/documents/document/acspc-044552.pdf; Accessed July 13, 2015. 18. Center for disease control and prevention. Arthritis Reports. Available at: http://www.cdc.gov/arthritis/basics/types.htm. Accessed July 13, 2015. 19. Sugiyama M, Atomi Y. Extrapancreatic neoplasms occur with unusual frequency in patients with intraductal papillary mucinous tumors of the pancreas. Am J Gastroenterol 1999;94:470–3. 20. Ikeuchi N, Itoi T, Sofuni A, et al. Prognosis of cancer with branch duct type IPMN of the pancreas. World J Gastroenterol 2010;16: 1890–5.
we can further understand why this disease seems to be becoming more and more prevalent. I think it is a fascinating concept. Dr. Roch: To answer your 1st question, patients with inflammatory bowel disease and lupus were discovered to have either a dilated main pancreatic duct or pancreatic cyst during follow-up of the autoimmune disease by their rheumatologist or their physician. Regarding patients with rheumatoid arthritis, it was a little bit more complicated. They are usually followed by X-ray, and the pancreatic condition was usually found incidentally on abnormal ultrasound or CT scan performed outside the scope of their rheumatoid arthritis follow-up. I found that several of them actually were diagnosed during work-up for kidney stones, which is totally outside the scope of the autoimmune disease. To answer your 2nd question, of the 96 patients who had autoimmune disease, 49 were asymptomatic. Of them, only 7 had surgery. None of them had an invasive carcinoma and only 1 patient had highly dysplastic IPMN. As for your comment, we were really excited too, but these are only preliminary data, it’s a large IPMN series but it’s a very small series of IPMN patients with autoimmune diseases with only 3% of invasive IPMN. This may have implications for screening of autoimmune patients but such conclusions are premature, and our data present, of course, the bias of referral and the bias of observation. And to confirm the relationship between the 2 diseases and the exact incidence of invasive IPMN in autoimmune patients, larger, and natural history studies will be needed. Dr. Robert P. Sticca (Grand Forks, ND): Your data, especially the extrapancreatic malignancies, would suggest a genetic basis for IPMNs in other malignancies. Have you looked at that or do you plan to look at it or do you know, is there any information on that? Dr. Roch: Actually, we wanted to confirm the same results as previous studies on the extrapancreatic malignancy, but it was not the main topic of the article, which is more about autoimmune disease. So we focused our data and results on this part and did not further analyze the extrapancreatic malignancy data. But thank you for your question. Dr. Roderich E. Schwarz (Goshen, IN): My question targets the same domain. Which disease comes 1st in the correlation with malignancy? So are patients followed for IPMN and then another extrapancreatic malignancy is diagnosed or not? You alluded to that with the autoimmune disease and the frequency in your conclusions slide. Any comments on that? And if there is a genetic basis, have you looked at histologic subtypes of IPMNs, tubular, and colloidal if there is a different mechanism for malignancies outside the pancreas? Dr. Roch: Once again, we did not analyze further the extrapancreatic malignancy aspect. Regarding autoimmune diseases, it was most of the time the autoimmune disease 1st and the IPMN along the way. So we don’t
Discussion Discussant Dr. Margo C. Shoup (Warrenville, IL): Of the patients with autoimmune disease, approximately half were symptomatic with regard to their intraductal papillary mucinous neoplasm (IPMN) compared with approximately 75% of those without autoimmune disease. So how were the autoimmune group diagnosed with IPMN? Were they just being followed with routine computed tomography (CT) scans or ultrasounds? Was it incidental finding? Was there some kind of surveillance that they were going through and they picked it up at that time? And what percentage of those that were asymptomatic actually had surgery and were found to have invasion or high risk IPMN? I think this is an important question. Clearly, the best study that could be done would be identifying the incidence of invasive or high risk IPMN in all patients with autoimmune disease, especially rheumatoid arthritis, lupus, and inflammatory bowel disease. I realize this is a little bit outside the scope of your study, but I hope that you’re looking at a way to look into this to see if
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know exactly the mechanism of it. It is the 1st series that describe it, and we will need basic science data and more epidemiological studies to further support our conclusions. Dr. Jeffrey Bender (Oklahoma City, OK): Would it be cost effective to screen all patients with autoimmune disease for an IPMN?
7 Dr. Roch: That is a good question concerning the public health aspect, especially the monetary aspect of it. We would need public health data to help find an answer. A lot of patients with autoimmune disease have a CT scan regularly for their disease unless it is a rheumatological disease. Serial CT-scan would be good enough to screen patients with autoimmune diseases for IPMN, but we have to confirm the association first.