A Prospective Study of Chemoradiotherapy as Primary Treatment in Patients With Locoregionally Advanced Penile Carcinoma.

PURPOSE: Neoadjuvant chemotherapy followed by surgery for locoregionally advanced penile carcinoma (LAPSCC) is associated with severe toxicity and a 1-year survival probability of ∼50%. We aimed to evaluate the safety and efficacy of chemoradiotherapy (CRT) as the primary treatment for LAPSCC and the association of high-risk human papillomavirus (hrHPV) with the outcome. METHODS AND MATERIALS: This was a prospective, single-center, single-arm study of CRT in LAPSCC, defined as a large/inoperable primary tumor, large palpable nodes, suspicion of extranodal extension or pelvic nodal involvement, and no distant metastases. CRT consisted of 49.5 Gy (33 × 1.5 Gy) on affected inguinal and pelvic areas combined with intravenous mitomycin C on day 1 and capecitabine on radiation days. Primary tumors and positron emission tomography/computed tomography-positive deposits received a boost of 59.4 Gy (33 × 1.8 Gy). The response was evaluated by 18F-fluorodeoxyglucose positron emission tomography/computed tomography. If feasible, patients with residual/recurrent disease underwent salvage surgery. The primary endpoint was 1-year progression-free survival (PFS), reached when 1-year PFS was ≥50%. Other endpoints were 2-year PFS, overall survival, and toxicity rates. Kaplan-Meier survival curves were compared using the log-rank test. RESULTS: Thirty-three patients were included: 29 (88%) with stage IV disease (T4 any-N M0 and/or any-T N3 M0) and 8 (24%) with hrHPV-positive disease. Median follow-up was 41 months. Thirty-two completed CRT. Eleven (33%) experienced ≥1 grade 3 treatment-related adverse event. There were no grade 4 or 5 treatment-related events. Twenty-four patients (73%) responded, including 13 (39%) complete responses. Nine patients (27%) underwent salvage surgery, and an additional 8 patients underwent later surgery (together 52%). One- and 2-year PFS were 34% and 31%, respectively. One- and 2-year overall survival were 73% and 46%, respectively. No significant difference between patients with hrHPV-positive and -negative tumors was observed. CONCLUSIONS: CRT is a viable treatment option for LAPSCC with acceptable toxicity. CRT can result in an enduring response. If patients have residual tumor, salvage surgery is feasible. HrHPV status was not associated with outcomes.

The Prognostic Value of Immune Factors in the Tumor Microenvironment of Penile Squamous Cell Carcinoma.

The host's immune system plays a pivotal role in many tumor types, including squamous cell carcinomas (SCCs). We aim to identify immunological prognosticators for lymph node metastases (LNM) and disease-specific survival (DSS) in penile SCC. For this retrospective observational cohort study, penile SCC patients (n = 213) treated in the Netherlands Cancer Institute, were selected if sufficient formalin-fixed, paraffin-embedded tumor material was available. Analysis included previously described high-risk human papilloma virus (hrHPV) status, immunohistochemical scores for classical and non-classical human leukocyte antigen (HLA) class I, programmed death ligand-1 (PD-L1) expression, and novel data on tumor-infiltrating macrophages and cytotoxic an regulatory T-cells. Clinicopathological characteristics and extended follow-up were also included. Regression analyses investigated relationships of the immune parameters with LNM and DSS. In the total cohort, diffuse PD-L1 tumor-cell expression, CD163+ macrophage infiltration, non-classical HLA class I upregulation, and low stromal CD8+ T-cell infiltration were all associated with LNM. In the multivariable model, only tumor PD-L1 expression remained a significant predictor for LNM (odds ratio (OR) 2.8, p = 0.05). hrHPV negativity and diffuse PD-L1 tumor-cell expression were significantly associated with poor DSS and remained so upon correction for clinical parameters [hazard ratio (HR) 9.7, p < 0.01 and HR 2.8, p = 0.03]. The only immune factor with different expression in HPV+ and HPV- tumors was PD-L1, with higher PD-L1 expression in the latter (p = 0.03). In the HPV- cohort (n = 158), LNM were associated with diffuse PD-L1 tumor-cell expression, high intratumoral CD163+ macrophage infiltration, and low number of stromal CD8+ T-cells. The first two parameters were also linked to DSS. In the multivariable regression model, diffuse PD-L1 expression remained significantly unfavorable for DSS (HR 5.0, p < 0.01). These results emphasize the complexity of the tumor microenvironment in penile cancer and point toward several possible immunotherapy targets. Here described immune factors can aid risk-stratification and should be evaluated in clinical immunotherapy studies to ultimately lead to patient tailored treatment.