Pathologic Complete Response After Chemoradiation of a Massive Primary Urethral Carcinoma

(A) Pretreatment biopsy reveals moderately to poorly differentiated infiltrating squamous cell carcinoma. Tumor cells are arranged in cords and nests, with large hyperchromatic nuclei, cytoplasmic keratin formation, necrosis, and increased mitotic activity (hematoxylin and eosin stain, 20×). (B) Posttreatment specimen reveals marked reactive change, focal fibrosis, and inflammatory infiltrates, with no residual tumor (hematoxylin and eosin stain, 20×). (C) Immunostain and (D) RNA stain for human papillomavirus p16 on the untreated tumor were negative