Coincidental Detection of Gastrointestinal Stromal Tumors During Laparoscopic Bariatric Procedures—Data and Treatment Strategy of a German Reference Center

  • Orestis Lyros
  • Yusef Moulla
  • Matthias Mehdorn
  • Katrin Schierle
  • Robert Sucher
  • Arne DietrichEmail author
Original Contributions



Intraoperative pathologic findings during bariatric surgery are relatively rare. Gastrointestinal stromal tumors (GISTs) are commonly located in the stomach and account for < 1% of all neoplasms of the alimentary tract. Coincidental detection of GISTs during bariatric surgery has been reported around 0.8%. We analyzed the incidence of GISTs in bariatric patients and investigated whether simultaneous resection can be oncologically adequate.


A single-center retrospective study of 707 morbidly obese patients, who underwent bariatric surgery (either Roux-en-Y gastric bypass (RYGB), One Anastomosis Gastric Bypass (OAGB), or sleeve resection (LSG) between January 2012 and August 2018). Intraoperative incidental GISTs were recorded and documented for tumor size, localization, immunoreactivity, and mitotic index.


Nine (1.27%) patients were identified with GISTs. Seven (78%) tumors were detected in women; mean age 55.6 (range 27–74), mean BMI 51.7 mg/m2 (range 38–71). GISTs were predominantly located in the stomach (78%) and two (22%) within the small bowel; six were found during RYGB vs. three during LSG. No abort of surgery or change of the intended procedure was necessary. All tumors (0.2–3.7 cm) were resected with disease-free surgical margins and displayed low malignancy. No adjuvant therapy was necessary.


The incidence of incidental GISTs in our series was higher to what has already been reported. Risk of malignancy was low and resection as part of the bariatric procedure was considered as definitive treatment. Suspicious tumors should be removed and confirmed by histology. In case of GIST histology, tumor resection with negative margins may be weighed as complete oncological treatment if there is low risk of malignancy.


GIST Bariatric surgery Incidental finding Laparoscopy 


Funding Information

This work was supported by the “Clinician Scientist Program” provided from the Medical Faculty of University of Leipzig to Mr. Orestis Lyros.

Compliance with Ethical Standards

Statement Regarding Ethics and Consent

For this type of study, formal consent is not required.

Conflict of Interest

The authors declare that they have no conflict of interest.


  1. 1.
    Miettinen M, Lasota J. Gastrointestinal stromal tumors: pathology and prognosis at different sites. Semin Diagn Pathol. 2006;23(2):70–83.CrossRefGoogle Scholar
  2. 2.
    Demetri GD, von Mehren M, Antonescu CR, et al. NCCN task force report: update on the management of patients with gastrointestinal stromal tumors. J Natl Compr Canc Netw. 2010;8(Suppl 2):S1–41. quiz S42–4CrossRefGoogle Scholar
  3. 3.
    Min KW, Leabu M. Interstitial cells of Cajal (ICC) and gastrointestinal stromal tumor (GIST): facts, speculations, and myths. J Cell Mol Med. 2006;10(4):995–1013.CrossRefGoogle Scholar
  4. 4.
    Yun HY, Sung R, Kim YC, et al. Regional distribution of interstitial cells of Cajal (ICC) in human stomach. Korean J Physiol Pharmacol. 2010;14(5):317–24.CrossRefGoogle Scholar
  5. 5.
    Hirota S, Isozaki K, Moriyama Y, et al. Gain-of-function mutations of c-kit in human gastrointestinal stromal tumors. Science. 1998;279(5350):577–80.CrossRefGoogle Scholar
  6. 6.
    Hirota S, Ohashi A, Nishida T, et al. Gain-of-function mutations of platelet-derived growth factor receptor alpha gene in gastrointestinal stromal tumors. Gastroenterology. 2003;125(3):660–7.CrossRefGoogle Scholar
  7. 7.
    Mochizuki Y, Kodera Y, Ito S, et al. Treatment and risk factors for recurrence after curative resection of gastrointestinal stromal tumors of the stomach. World J Surg. 2004;28(9):870–5.CrossRefGoogle Scholar
  8. 8.
    Swinburn BA, Sacks G, Hall KD, et al. The global obesity pandemic: shaped by global drivers and local environments. Lancet. 2011;378(9793):804–14.CrossRefGoogle Scholar
  9. 9.
    Calle EE, Thun MJ, Petrelli JM, et al. Body-mass index and mortality in a prospective cohort of U.S. adults. N Engl J Med. 1999;341(15):1097–105.CrossRefGoogle Scholar
  10. 10.
    Bhaskaran K, Douglas I, Forbes H, et al. Body-mass index and risk of 22 specific cancers: a population-based cohort study of 5·24 million UK adults. Lancet. 2014;384(9945):755–65.CrossRefGoogle Scholar
  11. 11.
    Park J, Morley TS, Kim M, et al. Obesity and cancer—mechanisms underlying tumour progression and recurrence. Nat Rev Endocrinol. 2014;10(8):455–65.CrossRefGoogle Scholar
  12. 12.
    Sjöström L, Lindroos AK, Peltonen M, et al. Lifestyle, diabetes, and cardiovascular risk factors 10 years after bariatric surgery. N Engl J Med. 2004;351(26):2683–93.CrossRefGoogle Scholar
  13. 13.
    Buchwald H, Avidor Y, Braunwald E, et al. Bariatric surgery: a systematic review and meta-analysis. JAMA. 2004;292(14):1724–37.CrossRefGoogle Scholar
  14. 14.
    Raghavendra RS, Kini D. Benign, premalignant, and malignant lesions encountered in bariatric surgery. JSLS. 2012;16(3):360–72.CrossRefGoogle Scholar
  15. 15.
    Ohanessian SE, Rogers AM, Karamchandani DM. Spectrum of gastric histopathologies in severely obese American patients undergoing sleeve gastrectomy. Obes Surg. 2016;26(3):595–602.CrossRefGoogle Scholar
  16. 16.
    Finnell CW, Madan AK, Ternovits CA, et al. Unexpected pathology during laparoscopic bariatric surgery. Surg Endosc. 2007;21(6):867–9.CrossRefGoogle Scholar
  17. 17.
    Tran T, Davila JA, El-Serag HB. The epidemiology of malignant gastrointestinal stromal tumors: an analysis of 1,458 cases from 1992 to 2000. Am J Gastroenterol. 2005;100(1):162–8.CrossRefGoogle Scholar
  18. 18.
    Sanchez BR, Morton JM, Curet MJ, et al. Incidental finding of gastrointestinal stromal tumors (GISTs) during laparoscopic gastric bypass. Obes Surg. 2005;15(10):1384–8.CrossRefGoogle Scholar
  19. 19.
    Yuval JB, Khalaileh A, Abu-Gazala M, et al. The true incidence of gastric GIST—a study based on morbidly obese patients undergoing sleeve gastrectomy. Obes Surg. 2014;24(12):2134–7.CrossRefGoogle Scholar
  20. 20.
    Crouthamel MR, Kaufman JA, Billing JP, et al. Incidental gastric mesenchymal tumors identified during laparoscopic sleeve gastrectomy. Surg Obes Relat Dis. 2015;11:1025–8.CrossRefGoogle Scholar
  21. 21.
    Chiappetta S, Theodoridou S, Stier C, et al. Incidental finding of GIST during obesity surgery. Obes Surg. 2015;25(3):579–83.CrossRefGoogle Scholar
  22. 22.
    Viscido G, Signorini F, Navarro L, et al. Incidental finding of gastrointestinal stromal tumors during laparoscopic sleeve gastrectomy in obese patients. Obes Surg. 2017;27(8):2022–5.CrossRefGoogle Scholar
  23. 23.
    Walędziak M, Różańska-Walędziak A, Kowalewski PK, et al. Bariatric surgery and incidental gastrointestinal stromal tumors—a single-center study: VSJ competition, 1st place. Wideochir Inne Tech Maloinwazyjne. 2017;12(3):325–9.Google Scholar
  24. 24.
    Søreide K, Sandvik OM, Søreide JA, et al. Global epidemiology of gastrointestinal stromal tumours (GIST): a systematic review of population-based cohort studies. Cancer Epidemiol. 2016;40:39–46.CrossRefGoogle Scholar
  25. 25.
    Berger NA. Obesity and cancer pathogenesis. Ann N Y Acad Sci. 2014;1311:57–76.CrossRefGoogle Scholar
  26. 26.
    Zhu CZ, Liu D, Kang WM, et al. Ghrelin and gastrointestinal stromal tumors. World J Gastroenterol. 2017;23(10):1758–63.CrossRefGoogle Scholar
  27. 27.
    Makris MC, Alexandrou A, Papatsoutsos EG, et al. Ghrelin and obesity: identifying gaps and dispelling myths. A Reappraisal In Vivo. 2017;31(6):1047–50.Google Scholar
  28. 28.
    Ekeblad S, Nilsson B, Lejonklou MH, et al. Gastrointestinal stromal tumors express the orexigen ghrelin. Endocr Relat Cancer. 2006;13(3):963–70.CrossRefGoogle Scholar
  29. 29.
    Agaimy A, Wünsch PH, Hofstaedter F, et al. Minute gastric sclerosing stromal tumors (GIST tumorlets) are common in adults and frequently show c-KIT mutations. Am J Surg Pathol. 2007;31(1):113–20.CrossRefGoogle Scholar
  30. 30.
    von Mehren M. Management of gastrointestinal stromal tumors. Surg Clin North Am. 2016;96(5):1059–75.CrossRefGoogle Scholar
  31. 31.
    Koch S, Besuch P. Gastrointestinal stromal tumors – retrospective classification of mesenchymal tumors of the gastrointestinal tract. DGHO 2003 [Abstract].Google Scholar
  32. 32.
    Kindblom LG, Meis-Kindblom J, Bümming P, et al. Incidence, prevalence, phenotype and biologic spectrum of gastrointestinal stromal cell tumors (GIST)–a population-based study of 600 cases. Ann Oncol. 2002;13(Suppl 5):157. Abstract 5770CrossRefGoogle Scholar
  33. 33.
    Nilsson B, Bümming P, Meis-Kindblom JM, et al. Gastrointestinal stromal tumors: the incidence, prevalence, clinical course, and prognostication in the preimatinib mesylate era—a population-based study in western Sweden. Cancer. 2005;103(4):821–9.CrossRefGoogle Scholar
  34. 34.
    Tryggvason G, Gíslason HG, Magnússon MK, et al. Gastrointestinal stromal tumors in Iceland, 1990—2003: the Icelandic GIST study, a population-based incidence and pathologic risk stratification study. Int J Cancer. 2005;117(2):289–93.CrossRefGoogle Scholar
  35. 35.
    Miettinen M, Sobin LH, Lasota J. Gastrointestinal stromal tumors of the stomach: a clinicopathologic, immunohistochemical, and molecular genetic study of 1765 cases with long-term follow-up. Am J Surg Pathol. 2005;29(1):52–68.CrossRefGoogle Scholar
  36. 36.
    Joensuu H. Gastrointestinal stromal tumor (GIST). Ann Oncol. 2006;17(Suppl 10):x280–6.CrossRefGoogle Scholar
  37. 37.
    Stiles ZE, Rist TM, Dickson PV, et al. Impact of body mass index on the short-term outcomes of resected gastrointestinal stromal tumors. J Surg Res. 2017;217:123–30.CrossRefGoogle Scholar
  38. 38.
    Hakimi AA, Furberg H, Zabor EC, et al. An epidemiologic and genomic investigation into the obesity paradox in renal cell carcinoma. J Natl Cancer Inst. 2013;105(24):1862–70.CrossRefGoogle Scholar
  39. 39.
    Hines RB, Shanmugam C, Waterbor JW, et al. Effect of comorbidity and body mass index on the survival of African-American and Caucasian patients with colon cancer. Cancer. 2009;115(24):5798–806.CrossRefGoogle Scholar
  40. 40.
    Brunner AM, Sadrzadeh H, Feng Y, et al. Association between baseline body mass index and overall survival among patients over age 60 with acute myeloid leukemia. Am J Hematol. 2013;88(8):642–6.CrossRefGoogle Scholar
  41. 41.
    Nonaka K, Ban S, Hiejima Y, et al. Status of the gastric mucosa with endoscopically diagnosed gastrointestinal stromal tumor. Diagn Ther Endosc. 2014;2014:429761.CrossRefGoogle Scholar
  42. 42.
    Gagner M. Comment on: gastric mesenchymal tumors as incidental findings during Roux-en-Y gastric bypass. Surg Obes Relat Dis. 2018;14(1):28–9.CrossRefGoogle Scholar
  43. 43.
    Gastrointestinal stromal tumours: ESMO-EURACAN clinical practice guidelines for diagnosis, treatment and follow-up Ann 2PG, Abecassis N, Aro HT, et al. Gastrointestinal stromal tumours: ESMO-EURACAN clinical practice guidelines for diagnosis, treatment and follow-up. Ann Oncol. 2018;29(Supplement_4):iv267.Google Scholar
  44. 44.
    Huang Z, Li Y, Zhao H, et al. Prognositic factors and clinicopathologic characteristics of small gastrointestinal stromal tumor of the stomach: a retrospective analysis of 31 cases in one center. Cancer Biol Med. 2013;10(3):165–8.Google Scholar
  45. 45.
    D’Ambrosio L, Palesandro E, Boccone P, et al. Impact of a risk-based follow-up in patients affected by gastrointestinal stromal tumour. Eur J Cancer. 2017;78:122–32.Google Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Division of Bariatric Surgery, Clinic of Visceral, Transplant, Thoracic and Vascular SurgeryUniversity HospitalLeipzigGermany
  2. 2.Institute of PathologyUniversity Hospital LeipzigLeipzigGermany
  3. 3.Integrated Research and Treatment Center (IFB) Adiposity DiseasesLeipzigGermany
  4. 4.Department of Visceral, Transplant, Thoracic and Vascular SurgeryUniversity HospitalLeipzigGermany

Personalised recommendations