Introduction: Relapsed locally advanced and/or metastatic penile cancer has an extremely poor prognosis with a need for effective therapy. This study retrospectively estimated the efficacy and tolerability of anti-programmed death receptor-1 (PD1) plus anti-epidermal growth factor receptor (EGFR) antibodies and combination chemotherapy in relapsed locally advanced and/or metastatic penile squamous cell carcinoma. Methods: A retrospective review of 30 relapsed locally advanced and/or metastatic (T4/N2-3/M1) penile squamous cell carcinoma received anti-PD1 plus anti-EGFR antibodies and cisplatin-based chemotherapy in Sun Yat-sen University Cancer Center from Jan 2018 to Aug 2022. Of 15 were chemotherapy-pretreated patients, and the remaining 15 were chemotherapy-naïve patients. Clinical responses were assessed using the Response Evaluation Criteria in Solid Tumours (RECIST v1.1) in 27 evaluable patients. Adverse events (AEs) were graded according to Common Terminology Criteria for Adverse Events (CTCAE v5.0). Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Results: Partial responses were observed in 63% (17/27) patients, and 14 were chemotherapy-naïve patients. The objective response rate (ORR) was 100% (14/14) and 23% (3/13) in chemotherapy-naïve and chemotherapy-pretreated patients, respectively. Fourteen patients subsequently received consolidated surgery. Eight patients achieved pathological complete response, and six were chemotherapy-naïve patients. The median follow-up time was 11.4 (range: 2.3-36.2) months. The median PFS and OS were 15.6 (1.0-32.6) and 20.9 (10.5-30.3) months in chemotherapy-pretreated patients, respectively. However, these were not reached in overall cohort and chemotherapy-naïve patients. 2-year PFS (OS) was 53% (62%) in overall cohort, whereas 75% (79%) and 35% (47%) in chemotherapy-naïve and chemotherapy-pretreated patients, respectively. Treatment-related AEs were experienced by all patients, with 60% (18/30) experiencing a grade 3 or 4 AEs. The most common grade 3-4 treatment-related AEs were lymphopenia (40%), anemia (23%), and neutropenia (13%). Conclusions: Anti-PD1 antibody plus anti-EGFR antibody and cisplatin-based combination chemotherapy were effective, well-tolerated, and satisfying long-term survival outcome for relapsed locally advanced and/or metastatic penile squamous cell carcinoma. However, prolonged follow-up and large prospective clinical trials are needed to validate the findings on this important issue. SOURCE OF Funding: This study was supported by the National Natural Science Foundation of China (No. 81772755).
