Virchows Archiv

, Volume 448, Issue 5, pp 644–647

Composite adenocarcinoma and large cell neuroendocrine carcinoma of the rectum

Case Report

DOI: 10.1007/s00428-006-0169-6

Cite this article as:
Makino, A., Serra, S. & Chetty, R. Virchows Arch (2006) 448: 644. doi:10.1007/s00428-006-0169-6


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.


RectumAdenocarcinomaNeuroendocrine carcinomaCombined carcinomaCytokeratin

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  1. 1.Department of PathologyUniversity Health Network, Princess Margaret HospitalTorontoCanada
  2. 2.Toronto Medical LaboratoriesUniversity of TorontoTorontoCanada