Neuroendocrine Tumors of Meckel’s Diverticulum: Lessons from a Single Institution Study of Eight Cases

Abstract

In conclusion, endocrine tumors of Meckel's diverticulum are rarely symptomatic and often diagnosed at an advanced stage. All tumors measuring more than 1 cm in diameter must be resected according to oncological principles.

Neuroendocrine Tumors Arising in Meckel's Diverticula: Frequency of Advanced Disease Warrants Aggressive Management

“…Less frequently, cases of patients with more florid symptoms of carcinoid syndrome resulting from a Meckel’s NET have been described[18,19,20]. The incidence of carcinoid syndrome in patients with ileal NETs is approximately 20–30%, which is similar to the 12–25% reported in patients with tumors arising from a Meckel’s diverticulum[10,12,21]. One of the patients (#1) in this series who had a large liver metastasis at the time of diagnosis presented with symptoms of carcinoid syndrome.…”

“…Although there are guidelines for the management of ileal and appendiceal NETs[24,25], the literature offers no consensus for the management of NETs arising from Meckel’s diverticula. Many would agree that Meckel’s NETs >2 cm are more often associated with metastases to regional lymph nodes and would therefore warrant wide resections to include adjacent small bowel and the associated mesenteric nodes[12]. Management of smaller Meckel’s NETs is less clear.…”

“…Some believe that in small, incidentally-found tumors, simple diverticulectomy or wedge resection is adequate, as such tumors are likely to be of a localized stage[11]. Such treatment decisions are based largely on experience with appendiceal NETs[6,12], as the appendix is also a small GI diverticulum that can serve as a primary site for NETs. Appendiceal NETs show little propensity for metastatic spread of tumors <2 cm[25].…”

“…Appendiceal NETs show little propensity for metastatic spread of tumors <2 cm[25]. However, the series by Poncet et al[12] cautions that even small Meckel’s NETS should be managed aggressively, as evidenced by nodal or distant metastases in 6 of their 8 patients, 5 of whom had tumors ≤2 cm in diameter. One patient in the current series had a 7 mm tumor and nodal metastases, as 2 other patients with tumors <2 cm (10 and 17 mm) had both nodal and liver metastases.…”

“…However, a recent series by Poncet et al examining eight cases found the incidence of metastases to be 75%[12]. Some authors believe that the rate of metastases arising from NETs of Meckel’s diverticula is falsely elevated, due to a greater tendency to report more advanced cases arising from this rare site, than to publish cases discovered incidentally[6].…”