Adaptive Stereotactic Radiotherapy for Localized Prostate Cancer

Intérêt de la radiothérapie Adaptative en stéréotaxie Prostatique

This study evaluates whether adaptive stereotactic body radiotherapy (SBRT) provides dosimetric advantages compared to non-adaptive SBRT in localized prostate cancer. Five low-dose CT scans are performed before each SBRT session to assess anatomical variations (bladder filling, rectal volume) and determine if a dosimetric recalculation would have been required. The study also evaluates cumulative dose to organs at risk, patient-reported quality of life over 24 months, and overall and recurrence-free survival.

Inclusion Criteria:

• Male aged ≥60 years
• Localized prostate cancer of low or intermediate risk (T1-T2)
• Gleason score 6-7
• PSA <15 ng/mL
• No evidence of metastatic disease
• Radiotherapy indicated for prostate cancer
• Affiliated with or benefiting from a French social security system
• French-speaking patient
• Patient appropriately informed and having signed a written informed consent form

Exclusion Criteria:

• Unable to read, write, or understand French
• Vulnerable patient as defined by Article L1121-6 of the French Public Health Code
• Adult under guardianship, curatorship, or legal protection ("sauvegarde de justice")
• Patient unable to personally provide informed consent according to Article L1121-8 of the French Public Health Code
• Patient already included in another interventional study that could interfere with study outcomes
• History of urological (prostate) or digestive surgery that could influence study outcomes
• Refusal to sign the written informed consent form