Histological grading of squamous cell carcinoma of the penis: a new scoring system.

A system of histological grading based on retrospective analysis of 239 patients with squamous cell carcinoma of the penis is presented. A new scoring system with 4 histological grades was used. The results of this study confirm previous reports that penile cancer is usually a highly (50%) or moderately (29%) differentiated squamous cell carcinoma. Poorly differentiated carcinomas and cancers of other types are very rare. The new grading system was found to be practical and a correlation between histological grade, clinical findings and prognosis was established. Patients with grade 1 tumours had an exceptionally favourable prognosis, with more than 80% being long-term survivors; for these patients, treatment with delayed side effects should be avoided and new forms of treatment should be explored.