This study compares two standard radiotherapy approaches (short-course vs. long-course) given before surgery in patients with locally advanced rectal cancer. The goal is to see which treatment is more effective and better tolerated.
Histologically confirmed adenocarcinoma of the rectum
Locally advanced disease based on MRI including cT3-T4 and/or node positive disease (cN1 or N2)
Tumor located within 15 cm from the anal verge (confirmed by endoscopy or MRI)
ECOG performance status 0-2
Metastatic disease at presentation (distant nodes, liver, lung, peritoneum, etc.)
Prior pelvic radiotherapy or systemic chemotherapy for rectal cancer
Presence of synchronous malignancies or previous malignancy within 5 years except: Treated basal cell or squamous cell carcinoma of the skin, In situ cervical cancer, Active uncontrolled infection
Known HIV infection with CD4 < 200 cells/μL, or active hepatitis B or C