Clinicopathological characteristics and frequency of multiple rectal neuroendocrine tumors: a single-center retrospective study
- 44 Downloads
Rectal multiple neuroendocrine tumors (M-NETs) are rare, with only few epidemiologic reports on the topic. Therefore, their clinicopathological features are not completely known, and the appropriate treatment strategy has not been established.
This study aimed to compare the clinicopathological malignant potential (lymphatic or venous invasion-positive and lymph node metastasis rates) of M-NETs with that of solitary NETs (S-NETs).
We retrospectively investigated 369 patients with NETs of the rectum. Patients who underwent colonoscopy at the Cancer Institute Hospital between January 1979 and 2016 and diagnosed with S-NETs were included, and S-NETs were found in 348 patients. Patients with M-NETs were classified into two groups as follows: patients with < 8 tumors (several (S) group, n = 21) and those with ≥ 8 tumors (numerous (N) group, n = 3).
The overall frequency of M-NETs was 5.7% and that of the N group was 0.8%. The mean tumor diameter in the N group was 6.0 mm (range, 4–8 mm). The lymphatic invasion rates of the S-NETs, and S and N groups of the M-NETs were 8.9%, 5.6%, and 66.7%, respectively. Moreover, the lymph node metastasis rates were 9.2%, 11.1%, and 33.3, respectively.
While M-NETs in the S and N groups had different characteristics, they were rarer in the N group. The N group may have higher rates of lymphatic invasion and lymph node metastasis regardless of tumor size.
KeywordsNeuroendocrine tumor Multiple rectal neuroendocrine tumor Gastrointestinal neuroendocrine tumor Lymph node metastasis Epidemiology for neuroendocrine tumor
We would like to thank the pathologists, Hiroshi Kawachi and Noriko Yamamoto, who contributed to the pathological diagnoses in this study.
Compliance with ethical standards
The study protocol was reviewed and approved by the institutional review boards of the participating institutions.
Conflict of interest
The authors declare that they have no conflict of interest.
- 1.Soga J (1994) Carcinoid tumors: a statistical analysis of Japanese series of 3126 reported and 1180 autopsy cases. Acta Med Biol 42:87–102Google Scholar
- 2.Ito T, Sasano H, Tanaka M, Osamura RY, Sasaki I, Kimura W, Takano K, Obara T, Ishibashi M, Nakao K, Doi R, Shimatsu A, Nishida T, Komoto I, Hirata Y, Nakamura K, Igarashi H, Jensen RT, Wiedenmann B, Imamura M (2010) Epidemiological study of gastroenteropancreatic neuroendocrine tumors in Japan. J Gastroenterol 45:234–243. https://doi.org/10.1007/s00535-009-0194-8 CrossRefPubMedGoogle Scholar
- 10.Konishi T, Watanabe T, Kishimoto J, Kotake K, Muto T, Nagawa H, on behalf of the Japanese Society for Cancer of the Colon and Rectum (2007) Prognosis and risk factors of metastasis in colorectal carcinoids: results of a nationwide registry over 15 years. Gut 56:863–868. https://doi.org/10.1136/gut.2006.109157 CrossRefPubMedPubMedCentralGoogle Scholar
- 12.Kobak AÇ, Zeybel M, Ayhan S (2006) Endoscopic submucosal resection of a rectal carcinoid tumor by cap aspiration - snare resection method. Turk J Gastroenterol 17:313–315Google Scholar
- 15.Bosman FT, Carneiro F, Hruban RH, Theise ND (2010) WHO classification of tumors of the digestive system, 4th edn. IARC Press, LyonGoogle Scholar
- 17.Maruyama M, Fukayama M, Koike M (1998) A case of multiple carcinoid tumors of the rectum with extraglandular endocrine cell proliferation. Cancer 61:131–136. https://doi.org/10.1002/1097-0142(19880101)61:1<131::aid-cncr2820610123>3.0.co;2-g CrossRefGoogle Scholar
- 18.Maggard MA, O’Connell JB, Ko CY (2004) Updated population-based review of carcinoid tumors. Ann Surg 240:117–122. https://doi.org/10.1097/01.sla.0000129342.67174.67 CrossRefPubMedPubMedCentralGoogle Scholar
- 22.Yao JC, Fazio N, Singh S, Buzzoni R, Carnaghi C, Wolin E, Tomasek J, Raderer M, Lahner H, Voi M, Pacaud LB, Rouyrre N, Sachs C, Valle JW, Fave GD, van Cutsem E, Tesselaar M, Shimada Y, Oh DY, Strosberg J, Kulke MH, Pavel ME, RAD001 in Advanced Neuroendocrine Tumours, Fourth Trial (RADIANT-4) Study Group (2016) Everolimus for the treatment of advanced, non-functional neuroendocrine tumors of the lung or gastrointestinal tract (RADIANT-4): a randomised, placebo-controlled, phase 3 study. Lancet 387:968–977. https://doi.org/10.1016/S0140-6736(15)00817-X CrossRefPubMedGoogle Scholar
- 26.Kasuga A, Chino A, Uragami N, Kishihara T, Igarashi M, Fujita R, Yamamoto N, Ueno M, Oya M, Muto T (2012) Treatment strategy for rectal carcinoids: a clinicopathological analysis of 229 cases at a single cancer institution. J Gastroenterol Hepatol 27:1801–1807. https://doi.org/10.1111/j.1440-1746.2012.07218.x CrossRefPubMedGoogle Scholar
- 28.Miller RR, Sumner HW (1982) Argyrophilic cell hyperplasia and an atypical carcinoid tumor in chronic ulcerative colitis. Cancer 50:2920–2925. https://doi.org/10.1002/1097-0142(19821215)50:12<2920::aid-cncr2820501235>3.0.co;2-n CrossRefPubMedGoogle Scholar