Stratification systems as prognostic tools for defining risk of lymph node metastasis in penile squamous cell carcinomas.

Inguinal lymph node metastasis is the single most important factor for predicting survival in patients with penile squamous cell carcinomas. To estimate the likelihood of this event, investigators have combined pathologic features of the primary tumor in the form of stratification systems. In this article we review 3 such systems (Solsona et al, J Urol 2001;165:1506; Hungerhuber et al, Urology 68:621, 2006; and Chaux et al, Am J Surg Pathol 2009;33:1049) built upon histologic grade, extent and depth of tumor invasion, and perineural invasion. We evaluate their usefulness, limitations, and possible implications for the management of patients with penile cancer. We also provide clues for the proper identification and interpretation of these pathologic features. Inguinal metastases were observed in 64% to 83% of patients in high-risk groups, 20% to 33% of intermediate groups, and 0% to 8% of low-risk groups. The results of these studies suggest that patients in high-risk groups could benefit from prophylactic bilateral groin dissection. In addition, patients in low-risk groups might be managed by surveillance alone. Finally, the authors suggest that additional approaches, such as sentinel lymph node biopsy, should be used for the intermediate-risk group. The identification of other pathologic features, such as vascular and perineural invasion, could tip the scales in problematic or paradoxical cases. The fate of these risk groups would be better defined by the identification of molecular biomarkers and genetic profiling.