Impact of pathologic features on local recurrence in penile squamous cell carcinoma after penectomy

Background

Penile squamous cell carcinoma (PSCC) is a rare malignancy that may be cured in cases of local disease by resection of the primary tumor. Risk factors and patterns of local recurrence (LR) have not been well described in cases requiring partial or radical penectomy. In this study, we evaluated risk factors for LR and the impact of frozen and final margin assessment.

Materials and methods

We evaluated 119 patients with PSCC who had undergone partial or radical penectomy from 2007 to 2023. Data regarding clinical and pathologic features were collected by retrospective chart review. The primary outcome of interest was LR. Determinants of LR were analyzed by Student's t, Fisher's exact, chi-square and logistic regression analysis. Predictive statistics of frozen margin status on final margin were assessed and LR rates for subsets of frozen and final margin interaction were defined. Finally, all cases of positive margins and LR were described to highlight patterns of LR and the importance of margin status in these cases.

Results

There were 8 (6.7%) cases of local recurrence. There were no significant predictors of LR, although a trend toward increased LR risk was observed among those with a positive final margin. Positive final margins were found in 15 (13%) cases. Frozen margin analysis was utilized in 79 cases, of which 10 (13%) were positive. The sensitivity, specificity, positive predictive value, and negative predictive value of frozen margin status for final margins were 44%, 92%, 40%, and 93%, respectively. There were no LR among cases in which frozen margin was not sent. Analysis of all cases with positive margin and/or LR identified three subsets of patients: CIS or focally positive margin resulting in either no LR or LR managed with minimal local intervention, bulky disease in which survival is determined by response to subsequent therapy rather than local recurrence, and clinically significant local recurrence requiring continued surveillance and intervention despite negative margins.

Conclusions

LR is rare, even in cases of larger, proximal tumors requiring partial or radical penectomy. In this study, no statistically significant risk factors for local recurrence were identified; however, analysis of frozen and final margins provided insight into the importance of margin status and patterns of local recurrence. When feasible, visibly intra-operative negative margins are an excellent predictor of low risk for LR, and, in cases of CIS or focally positive margins, further resection to achieve negative margins is unlikely to reduce the risk of clinically significant LR. Additionally, in cases of bulky disease, the goals of resection should be focused toward palliation and next line therapy.