Adherence to guideline recommendations for lymph node dissection in squamous cell carcinoma of the penis : effect on survival and complication rates

Introduction: We analyzed adherence rates to contemporary guidelines regarding inguinal lymph node dissection (ILND) for squamous cell carcinoma of the penis, as well as ILND association with cancer specific mortality (CSM), and complication rates. Materials and methods: Within the Surveillance, Epidemiology, and End Results and the National Inpatient Sample databases, 943 and 317 nonmetastatic penile cancer patients (1998–2015) were respectively identified. Multivariable analyses focused on ILND rates, CSM, and complication rates. Inverse probability of treatment weighting adjustment was used in CSM analyses. Results: Within the Surveillance, Epidemiology, and End Results database, ILND was performed in 233 (24.7%) patients. ILND rates did not vary over time (P = 0.2). In the overall cohort (n = 943), ILND was an independent predictor of lower CSM (hazards ratio [HR]: 0.42; P < 0.001). In Multivariable CSM analyses stratified according to N-stage, ILND was associated with lower CSM in N1 (HR: 0.25; P < 0.001) and N2-3 (HR: 0.42; P = 0.01), but not in N0 patients. Within the National Inpatient Sample database, presence of LN invasion (LNI) was associated with longer hospitalization (odds ratio: 1.27, P = 0.01), but not with higher complications or in-hospital mortality. Conclusions: The adherence to guidelines for ILND was low (24.7%), and did not change over time. Nonetheless, a CSM benefit related to ILND was observed in N1, N2, and N3 patients. Complication rates and in-hospital mortality did not differ according to LNI. However, hospital stay may be longer in LNI patients. Finally, it should be noted that lack of distinction between clinical and pathological N-stage represents an important limitation.