Factors Predicting Nodal Metastasis in Penile Cancer: Analysis from a Tertiary Center.

Introduction: Lymph node metastasis is an important prognostic marker in penile cancer. Identification of occult metastasis is by lymphadenectomy based on the histological features of primary tumor; however, this leads to unnecessary surgical morbidity in node negative patients.

Methods: A retrospective analysis of all surgically treated penile cancer patients managed at our institute from January 2011 to March 2014 was performed. Patient characteristics, histological factors, and lymph node involvement were identified. Logistic regression analysis was used to compute odds ratio (OR) in univariate and multivariate analysis.

Results: Ninety seven patients underwent surgical management at our institute during the abovementioned period. Grade III tumor, presence of lymphovascular invasion, tumor thickness >10 mm, perineural invasion (PNI) and Ki67 >50% were significantly associated with nodal metastasis. On multivariate analysis, only presence of PNI was found to be significant (OR: 6.82) (95% confidence interval: 1.72-27.03) (p = 0.006).

Conclusion: PNI is a strong independent predictor of occult lymph node metastasis in penile cancers. Its inclusion in stratification of clinically node negative patients will identify high-risk patients who will benefit from prophylactic lymphadenectomy.