Adherence to Guideline Recommendations for Perioperative Chemotherapy in Patients with pN2-3 M0 Squamous Cell Carcinoma of the Penis: Temporal Trends and Survival Outcomes

Aims: To analyse contemporary perioperative chemotherapy (CHT) guideline adherence rates for pN2-3 M0 squamous cell carcinoma of the penis, as well as CHT association with cancer-specific (CSM) and other-cause mortality (OCM). Materials and methods: Within the Surveillance, Epidemiology, and End Results databases, 311 pN2-3 M0 squamous cell carcinoma of the penis patients treated with inguinal lymph node dissection were identified. Univariable and multivariable logistic regression analyses focused on CHT rates, whereas cumulative incidence plots and multivariable competing risks regression analyses tested for CSM and OCM rates. Results: CHT was administered to 140 (45%) patients and rates increased from 37.5 to 62.2% (2004–2015; P = 0.02). Specifically, annual CHT rates increased over time in patients younger or equal to 65 years and in patients older than 65 years (44.4–84.6% versus 28.6–50%, respectively), but this trend was not statistically significant (P = 0.1 and P = 0.2, respectively). The median follow-up was 13 months for both CHT (interquartile range 8.0–32.2) and no-CHT subgroups (interquartile range 5.0–40.0). In multivariable logistic regression analyses, more contemporary year of diagnosis interval (odds ratio 2.08, P < 0.01) and age older than 75 years (odds ratio 0.14, P < 0.001) were independent predictors of CHT use. In multivariable competing risks regression analyses, CHT use did not affect CSM (hazard ratio 1.02; P = 0.7) or OCM (hazard ratio 1.56; P = 0.8). Conclusions: CHT adherence rates sharply increased in the most recent years. Despite this increase over time, the lack of efficacy regarding CSM benefit is disappointing.