Basaloid squamous cell carcinoma occurring in the urinary bladder

Basaloid squamous cell carcinoma is a recently described, distinct variant of squamous cell carcinoma that arises predominantly in the upper aerodiges tive tract. Herein we report a case of basaloid squamous cell carcinoma ari sing in the urinary bladder. The patient was a 60-year-old woman who experi enced intractable urinary tract infections following multiple corrective su rgical procedures for incontinence. Biopsies of cystoscopically evident fla t lesions were performed, and the patient subsequently underwent a radical cystectomy. Histologically, the lesions consisted of nests of basaloid cell s with brisk mitotic activity, areas of squamous differentiation along with areas of squamous metaplasia, and squamous cell carcinoma in situ. These f eatures are similar to those of basaloid squamous cell carcinoma described elsewhere in the body To our knowledge, this is the first reported case of basaloid squamous cell carcinoma in the urinary bladder.