Pseudoglandular (adenoid, acantholytic) penile squamous cell carcinoma: a clinicopathologic and outcome study of 7 patients.

Almost half of penile squamous cell carcinomas (SCCs) are of the usual type but there is a variegated spectrum of morphologically distinctive subtypes. In a pathologic review of 375 uniformly diagnosed and treated patients with penile SCC, we found 7 tumors with predominant pseudoglandular or adenoid features. The aim of the study was to delineate clinicopathologic features and outcome of an unusual variant of penile SCC. Clinical charts and pathologic materials were reviewed. The following informations were obtained: patient's age, tumor site, size, histologic grade (1, 2, and 3), thickness in millimeters, anatomic level of invasion [corpus spongiosum, corpus cavernosum (CC)], vascular and perineural invasion, groin nodal status, and follow-up in months. These features were compared with those of 224 cases of usual SCCs. Median age of the patients was 54 years. Tumors were large (average 4.6 cm) and involved multiple sites in 4 cases; exclusively the glans in 2 and site was unknown in 1. Microscopically, tumors were SCC with acantholytic areas ranging from solid nests with early necrosis or empty pseudoluminal spaces lined by 1 layer of squamous cells or cylindrical cells strikingly simulating glands. Tumors were deeply infiltrating (4 invaded CC, 2 corpus spongiosum, and 1 invaded preputial dermis) and were of high histologic grade (6 cases). Vascular invasion was present in 4 cases and perineural invasion in 2. The differential diagnosis was with gland forming penile tumors (surface adenosquamous, mucoepidermoid, and urethral adenocarcinomas) and the angiosarcomatoid variant of sarcomatoid carcinomas. There was regional nodal metastasis in 3 patients, 2 of which died from disease. The other 5 were either alive with no evidence of disease (12 and 21 y after diagnosis) or died from causes other than penile cancer (3, 4, and 7 y after diagnosis). Comparing with usual SCCs, pseudoglandular SCCs were of higher grade (88% vs. 44%), invaded deeper into CC (71% vs. 52%), and showed a higher incidence of regional metastasis (42% vs. 25%) and higher mortality (29% vs. 19%).