Important Therapeutic Considerations in T1b Penile Cancer: Prognostic Significance and Adherence to Treatment Guidelines.

BACKGROUND

The clinical implications and contemporary management of T1b penile cancer are unknown. National treatment guidelines advocate surgical lymph node examination (SLNE) for T1b disease.

OBJECTIVE

The aim of this study was to evaluate the prognosis of T1b disease and adherence to corresponding treatment guidelines.

METHODS

We analyzed 296 patients from two academic centers, and 1263 patients from the Surveillance, Epidemiology, and End Results (SEER) registry (median follow-up 48.3 and 21 months, respectively). Multivariate Cox and Fine-Gray regressions were applied for penile cancer-specific survival (PCSS) analyses.

RESULTS

In the academic center cohort, 28.3% of T1 patients had T1b disease, all of whom underwent SLNE. Nodal metastases were detected in 86.7% of T1b patients and 13.2% of T1a patients (p < 0.001). Using T1a as a reference, PCSS was significantly poorer in the T1b patients, with an adjusted hazard ratio (aHR) of 4.10 (p = 0.03). In the SEER cohort, 16.8% of T1 patients were classified as T1b. SLNE was performed in 21.7% of the T1b patients versus 38.2% of the T2 patients (p = 0.002). The probability of nodal metastases was 2.23-fold higher in T1b patients than in T1a patients (p < 0.001). In clinical N0M0 patients without SLNE, compared with T1a disease, T1b was associated with an aHR of 4.40 and a subdistribution HR of 4.53 for PCSS (both p = 0.003).

CONCLUSIONS

T1b penile cancer is strongly associated with nodal metastases and adverse PCSS, and is poorly managed according to guidelines recommended in the nationwide registry.