Long-term Outcomes of Salvage Radiotherapy Using TomoTherapy With Image-guided Radiotherapy for Postoperative...

Area of Science:

• Oncology
• Radiation Oncology
• Medical Physics

Background:

• Prostate cancer recurrence after radical prostatectomy often necessitates salvage radiotherapy (SRT).
• Intensity-modulated radiation therapy and image-guided radiation therapy (IMRT-IGRT) offer precise radiation delivery.
• TomoTherapy is a specific IMRT-IGRT platform used in SRT.

Purpose of the Study:

• To evaluate the long-term outcomes of salvage radiotherapy (SRT) using TomoTherapy IMRT-IGRT in postoperative prostate cancer patients.
• To assess treatment-related toxicity associated with this SRT approach.
• To identify factors influencing outcomes in patients receiving SRT.

Main Methods:

• A cohort of 71 consecutive patients undergoing SRT after radical prostatectomy between 2011 and 2023 was analyzed.
• Progression-free rate (PFR) and overall survival were calculated using Kaplan-Meier curves.
• Cox proportional hazards regression was used to analyze factors associated with treatment outcomes.

Main Results:

• The median follow-up was 60 months. The 5-year and 10-year PFR were 69.05% and 54.73%, respectively.
• Elevated maximum PSA >0.7 ng/ml was significantly associated with a worse PFR (p<0.05).
• Late toxicities included grade 2 genitourinary (11.3%) and gastrointestinal (1.4%) events; no grade 3 or higher toxicities were reported.

Conclusions:

• IMRT-IGRT using TomoTherapy as SRT provides comparable long-term progression-free rates to previous studies for prostate cancer.
• Maximum PSA level >0.7 ng/ml is a significant prognostic factor for worse outcomes.
• This SRT approach demonstrates efficacy with a favorable toxicity profile.