Adenomyoma Arising in a Meckel Diverticulum: Case Report and Review of the Literature

Abstract

We report a case of adenomyoma of the small intestine arising in a Meckel diverticulum. The patient was a 22-month-old boy who presented with signs and symptoms of intussusception. At surgery, a Meckel diverticulum was found and removed. On histologic examination, a tumor consisting of dilated cystic glands and smooth muscle bundles was identified. A diagnosis of adenomyoma arising in a Meckel diverticulum was made. A review of the literature showed that only six other pediatric cases of adenomyoma of the small intestine have been reported. The presence of an adenomyoma in a young patient within a Meckel diverticulum favors the view that adenomyomas are a variant of pancreatic heterotopia.

Adenomyoma of the small intestine

“…Accordingly, the pattern of cytokeratin expression [CK 7 (+), CK 20 (-)] of the glandular element of adenomyoma coincides with that of the pancreatic duct epithelium but not with that of the intestinal epithelium, thus supporting the heterotopic pancreas theory. This theory was further supported by Babál et al [30] 's detection of histochemical reactivities of the duodenal adenomyoma similar to the reactivities of duct epithelium in the neighboring pancreas, as well as Yao et al [17] 's reporting of a case of adenomyoma occurring in a Meckel diverticulum. In their examination of a case series of adenomyoma of the Vaterian system, Handra-Luca et al [2] identified that 3 of 13 cases were characterized by pancreatic heterotopias with both exocrine and endocrine pancreatic tissue being present in continuity with the adenomyoma.…”

“…The actual incidence is unclear because very few cases have been reported. A further complicating factor in determining its true incidence is that its reportedly low incidence may be partly attributed to underreporting or nonrecognition of the condition by both surgeons and pathologists [17] . We have diagnosed 3 cases of asymptomatic adenomyoma of the jejunum or ileum at autopsy in our institution within the past 8 years; this fact suggests that its incidence is higher than suspected.…”

“…The lesion occurs 2 to 3 times more frequently in the ileum than in the jejunum. One lesion was found in a Meckel diverticulum [17] .…”

Ileal Adenomyoma: Extremely Rare Cause of Intussusception

“…Adenomyoma located in the small intestine most frequently present with intussusception. It may rarely cause ileus, and can be detected incidentally (1)(2)(3)(4). As the mass is small, none of the cases has been reported to be identified by imaging methods before surgery.…”

“…In the published English literature, the lesion was located in the ileum in approximately 75% of pediatric patients in whom the site of the lesion was determined, and Meckel's diverticulum was identified in 16.6% of them (1)(2)(3)(4)7). Adenomyoma located in the small intestine most frequently present with intussusception.…”