The purpose of this study was to evaluate the efficacy and safety of PD-1 blockade combined with cisplatin and paclitaxel (TP)-based chemotherapy as first-line treatment for advanced penile squamous cell carcinoma (PSCC).
A retrospective review was performed of 32 eligible patients with high-risk stage IV (cN3M0-1) PSCC who received first-line PD-1 blockade combined with TP-based chemotherapy at 5 medical centers (2019-2023). Clinical responses were assessed using RECIST version 1.1. Treatment-related adverse events (TrAEs) and postsurgical complications were graded according to CTCAE version 5.0. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Multiplex immunofluorescence was used to explore potential biomarkers and to present the tumor microenvironment landscape before and after treatment.
After a median treatment duration of 4 cycles (range, 2-6), the overall objective response rate was 78.1% (25/32). Among 27 patients with locally advanced PSCC, 13 (48.1%) subsequently underwent consolidative surgery and 6 (22.2%) achieved a pathologic complete response (pCR). Additionally, 8 (25.0%) patients in the overall cohort underwent consolidated radiotherapy. Median follow-up was 21.1 months (95% CI, 14.1-42.7). Median PFS and OS were 15.0 months (95% CI, 11.4-not available [NA]) and 19.3 months (95% CI, 16.7-NA), respectively. All patients experienced TrAEs, with 50% (16/32) of them having grade ≥3 TrAEs. Higher intratumoral CD8+ T-cell infiltration was observed in pretreatment samples of responders compared with nonresponders (P=.03). CD4+ T-cells, natural killer cells, and macrophages, among others, exhibited significant changes after treatment (all P<.05), suggesting their potential involvement in the antitumor response to immunochemotherapy.
PD-1 blockade plus TP-based chemotherapy was effective and well tolerated, with favorable survival outcomes for patients with stage IV PSCC. High pretreatment intratumoral CD8+ T-cell infiltration may help to identify potential responders.
Journal of the National Comprehensive Cancer Network : JNCCN. 2024 Dec 20 [Epub ahead of print]
Longbin Xiong, Xingli Shan, Huali Ma, Shengjie Guo, Jiyan Liu, Xianda Chen, Wenjun Meng, Bin Guo, Lijuan Jiang, Ru Yan, Xin An, Yanxia Shi, Yijun Zhang, Ting Xue, Lichao Wei, Daming Xu, Zhiling Zhang, Zike Qin, Kai Yao, Yajian Li, Philippe E Spiess, Linjun Hu, Nianzeng Xing, Hui Han
1Department of Urology, State Key Laboratory of Oncology in Southern China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China., 3Department of Urology, Cancer Hospital of Huanxing Chaoyang District Beijing, Beijing, China., 2State Key Laboratory of Oncology in Southern China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou, China., 5Department of Biotherapy and Cancer Center, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China., 6Department of Urology, Sun Yat-sen University Cancer Center Gansu Hospital, Guangzhou, China., 9Department of Urology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China., 10Department of Genitourinary Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL.