Is an Incidental Meckel's Diverticulum Truly Benign?

Abstract

Meckel's diverticulum is the most common congenital abnormality of the gastrointestinal tract and it is found to affect nearly 2 percent of the population. Interestingly, the surgical management of an asymptomatic Meckel's diverticulum remains widely controversial in the adult population. Review of the literature finds the overall risk of Meckel's diverticulum becoming symptomatic to be low; however, the risk accompanying its resection also proves to be minimal thus perpetuating the question of its proper management. We report our experience with an elderly patient who required an emergent operative intervention and was incidentally found to have Meckel's diverticulum. Review of final pathology found Meckel's diverticulum to contain a carcinoid tumor. In our review, the presence of a carcinoid tumor within Meckel's diverticulum is a rare finding, but its incidence may further support the resection of incidentally found asymptomatic Meckel's diverticulum in patients of all ages.

Figure 1

Coronal section from computer tomography imaging demonstrating the point of colonic volvulus (red arrows) within the transverse colon (T).

Figure 2

Resected specimen which included the ascending and transverse colon, terminal ileum (TI), and Meckel's diverticulum (M). The small bowel transection point was chosen just proximal to the Meckel's diverticulum (red arrow).

Figure 3

Gross specimen showing the Meckel's diverticulum (M) in relation to the terminal ileum (TI) and the proximal surgical staple line (red arrows). As shown, the Meckel's diverticulum had a relatively broad base; its measurements were 3.5 × 3.0 × 2.5 cm.

Figure 4

Low power view of the Meckel's diverticulum. Histological review did not reveal any aberrant tissue types.

Figure 5

(a) Low power view of the incidental carcinoid found within the Meckel's diverticulum. The tumor was found to be 0.6 cm in its greatest dimension and showed invasion of the subserosa without involvement of the visceral peritoneum. Proximal and distal margins were uninvolved. Pathological staining was consistent with a pT2N0Mx carcinoid tumor. (b) High power view of the carcinoid tumor showing its acinar nests of uniform-appearing cells.

Figure 6

Histological analysis of this carcinoid found it to have a low proliferation index and therefore consistent with that of a low grade neuroendocrine tumor. Additional confirmatory immunohistological analysis found its cells to be positive for (a) synaptophysin and (b) chromogranin.