HISTOLOGY AND HISTOPATHOLOGY

Cellular and Molecular Biology

 

Tailgut cyst associated with a carcinoid tumor: case report and review of the literature

A. Mathieu1, R. Chamlou2, F. Le Moine3, C. Maris1, J. Van de Stadt2 and I. Salmon1

1Department of Pathology, Erase Hospital, Free University of Brussels, Belgium, 2Department of Digestive Surgery, Erasme Hospital, Free University of Brussels, Belgium and 3Department of Medicine, Erase Hospital, Free University of Brussels, Belgium

Offprint requests to: Isabelle Salmon, MD, PhD, Laboratory of Pathology – Erasmus Hospital, 808 route de Lennik – B-1070. e-mail: isalmon@ulb.ac.be


Summary. We report the case of a 49-year-old woman who presented a tailgut cyst lined by a variety of epithelium including squamous, columnar and transitional. Fortuitously a microscopic carcinoid tumor expressing immunohistochemically neuroendocrine markers was identified in the cystic wall.
Tailgut cysts are congenital abnormalities located in the presacrococcygeal area occurring usually in adult patients. Clinical diagnosis is difficult because they are often asymptomatic. Patients may present symptoms resulting from local mass effects or complications. The differential diagnoses include rectal duplication cysts, cystic sacrococcygeal teratomas, epidermal cysts, epidermoid cysts, anal duct or gland cysts. Magnetic resonance imaging has recently become the modality of choice to image the cyst. Malignant transformation is rare; 23 cases including 10 carcinoid tumors have been reported in the literature. To our knowledge, this is the eleventh case of carcinoid tumor arising in a tailgut cyst. Histol Histopathol 20, 1065-1069 (2005)

Key words: Tailgut cyst, Carcinoid tumor, Presacrococcygeal tumor