A CASE OF SQUAMOUS CELL CARCINOMA IN SITU OF THE ANAL CANAL

Abstract

Squamous cell carcinoma in situ of the anal canal is very rare. This case is the 6th reported case in Japan. It is a case which was correctly diagnosed by colonoscopy and was treated by surgical partial resection of the anal canal. A 62-year-old woman was hospitalized because of severe conspitation. Colonoscopy revealed a polyp of lomm in diameter in the anal canal by a turn-over method in the rectum. Biopsy specimen showed moderately differentiated squamous cell carcinoma. Partial anal canal resection was performed after a diagnosis of squamous cell carcinoma in situ of the anal canal was made. Pathological findings of the resected specimen revealed an elevated lesion with defined margins, l0mm in diameter situated in close proximity to the dentate line. The histology of the elevated lesion revealed squamous cell carcinoma in situ. Careful inspection of the anal canal by colonoscopy and anoscopy is essential for the early diagnosis of cancer in the anal canal.