Composite adenocarcinoma and large cell neuroendocrine carcinoma of the rectum.

Abstract

Composite glandular-endocrine tumors of the gastrointestinal tract are rare neoplasms. Even more uncommon are the so-called amphicrine tumors, lesions in which dual epithelial and endocrine differentiation occurs in the same cell. We describe a patient who complained of rectal pain and bleeding with a mixed or composite adenocarcinoma and neuroendocrine carcinoma of the rectum. Histological examination revealed a distinct adenocarcinoma of conventional type with glandular structures admixed intimately with a neuroendocrine carcinoma. The latter component was deeply infiltrative, while the adenocarcinoma occupied the more superficial aspect of the tumor. What was interesting was the immunophenotype of the lesion: cytokeratin (CK) 20 expression was very focal in the adenocarcinoma component and negative in the neuroendocrine carcinoma, while CK 7 was expressed strongly in the adenocarcinoma and only focally in the neuroendocrine component. This cytokeratin profile suggests a possible origin from the anal transitional zone.

• Authors: A Makino, S Serra, R Chetty
• Journal: Virchows Archiv : an international journal of pathology (Virchows Arch) Vol. 448 Issue 5 Pg. 644-7 (May 2006) ISSN: 0945-6317 [Print] Germany
• PMID: 16508780 (Publication Type: Case Reports, Journal Article)

Topics

• Adenocarcinoma (metabolism, pathology)
• Aged, 80 and over
• Carcinoma, Large Cell (metabolism, pathology)
• Carcinoma, Neuroendocrine (metabolism, pathology)
• Female
• Humans
• Immunohistochemistry
• Neoplasms, Multiple Primary (metabolism, pathology)
• Rectal Neoplasms (metabolism, pathology)