Proton therapy (PT) has emerged as a standard-of-care treatment option for localized prostate cancer at our comprehensive cancer center. However, there are few large-scale analyses examining the long-term clinical outcomes. Therefore, this article aims to evaluate the long-term effectiveness and toxicity of PT in patients with localized prostate cancer.
Review of 2772 patients treated from May 2006 through January 2020. Disease risk was stratified according to National Comprehensive Cancer Network guidelines as low [LR, n=640]; favorable-intermediate [F-IR, n=850]; unfavorable-intermediate [U-IR, n=851]; high [HR, n=315]; or very high [VHR, n=116]. Biochemical failure and toxicity were analyzed using Kaplan-Meier estimates and multivariate models.
The median patient age was 66 years; the median follow-up time was 7.0 years. Pelvic lymph node irradiation was prescribed to 28 patients (1%) (2 [0.2%] U-IR, 11 [3.5%] HR, and 15 [12.9%] VHR). The median dose was 78 Gy in 1.8-2.0 Gy(RBE) fractions. Freedom from biochemical relapse (FFBR) rates at 5 years and 10 years were 98.2% and 96.8% for the LR group; 98.3% and 93.6%, F-IR; 94.2% and 90.2%, U-IR; 94.3% and 85.2%, HR; and 86.1% and 68.5%, VHR. Two patients died of prostate cancer. Overall rates of late grade ≥ 3 GU and GI toxicity were 0.87% and 1.01%.
Proton therapy for localized prostate cancer demonstrated excellent clinical outcomes in this large cohort, even among higher-risk groups with historically poor outcomes despite aggressive therapy.
Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology. 2023 Aug 17 [Epub ahead of print]
Alan J Sosa, Howard D Thames, Jeremiah W Sanders, Seungtaek L Choi, Quynh-Nhu Nguyen, Henry Mok, X Ron Zhu, Shalin Shah, Lauren L Mayo, Karen E Hoffman, Chad Tang, Andrew K Lee, Thomas J Pugh, Reena Kudchadker, Steven J Frank
Departments of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX., Departments of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX. Electronic address: ., Departments of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX., Departments of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX., Texas Center for Proton Therapy, Irving TX., University of Colorado Denver, Aurora, CO., Departments of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX. Electronic address: .