Ectopic Breast Tissue Presenting as an Anal Polyp

Gross examination revealed an irregularly shaped tan polyp, measuring 2.5 cm in greatest dimension. Sectioning revealed pink-tan tissue with a cystic component containing clear fluid. Microscopic examination showed a polypoid fragment of tissue lined on the outer aspect by squamous epithelium with f...

Full description

Saved in:
Bibliographic Details
Published in:Canadian Journal of Surgery 2007-12, Vol.50 (6), p.E23-E24
Main Authors: Chan, Nancy G., MD, Penswick, John L., MD, Labelle, Eric, MD, Driman, David K., MB ChB
Format: Article
Language:English
Subjects:
Anus Diseases - pathology
Anus Diseases - surgery
Breast
Care and treatment
Case Note
Case studies
Choristoma - pathology
Choristoma - surgery
Development and progression
Diagnosis
Excretory system
Female
Humans
Injuries
Medical diagnosis
Middle Aged
Rectal polyps
Surgery
Tissues
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Gross examination revealed an irregularly shaped tan polyp, measuring 2.5 cm in greatest dimension. Sectioning revealed pink-tan tissue with a cystic component containing clear fluid. Microscopic examination showed a polypoid fragment of tissue lined on the outer aspect by squamous epithelium with focal hyperkeratosis and parakeratosis (Fig. 2). Within the core of the polyp, there were mammary ducts and lobules with focal apocrine metaplasia (Fig. 2). Many of the ducts were cleft-like and dilated, imparting a fibroadenomatoid appearance. Some of the duct epithelium showed mild epithelial hyperplasia. The stroma was not hypercellular, and there was no evidence of malignancy. Features of hidradenoma papilliferum were absent. Immunohistochemical testing demonstrated diffuse positivity for cytokeratin 7 and progesterone receptor protein within the epithelial cells and focal positivity for estrogen receptor protein. The pathological features were those of breast tissue. To the best of our knowledge, this is the first documented case of ectopic breast tissue arising in the anus and presenting as an anal polyp. Ectopic breast tissue has been reported in the axillae and vulva, and less commonly in the buttock, neck, face, flank, arms, hips, shoulders and back.2,5 Such findings occur as a result of either extramammary buds along the primitive milk line or aberrant tissue located outside the milk line.1 We believe that the ectopic tissue in this report represents a remnant from the developing milk line.
ISSN:0008-428X
1488-2310
DOI:10.1016/S0008-428X(07)50166-9