Reply to Y.-N. Feng et al

Abstract

We thank Feng et al 1 for their interest in our manuscript reporting the results of the PERICLES trial. 2 In this phase II trial, patients with stage IV penile cancer were treated with atezolizumab (anti-PD-L1) with or without radiotherapy (RT).Patients with penile cancer with locoregional metastasis experience a high rate of metastasis-associated morbidity and often have rapid progression. 3,4 We, therefore, felt that therapy aimed at locoregional control was needed in the subset of patients at risk for locoregional progression. At the time of trial conception, our standard of care for the treatment of patients with penile cancer with locoregional metastases was chemoradiation of the penis, inguinal, and pelvic lymph nodes. 5 Chemoradiation in combination with atezolizumab could have potentially led to increased toxicity and would have made the trial too heterogeneous, particularly in the interpretation of the clinical efficacy of atezolizumab. Consequently, we concluded that RT alone, using the same schedule, was justified for patients in whom a palliative benefit was expected. This decision to administer RT was per investigator, supported by the multidisciplinary tumor board, and not mandated by any specific disease stage.Since the conception by the PERICLES trial, the field of radiotherapeutic immune induction has evolved, as discussed in our manuscript. Future treatment strategies could build on these biologic insights.