This study evaluates whether an arginine-free diet combined with chemoradiotherapy can improve treatment outcomes in patients with locally advanced rectal cancer. Our previous study showed that an arginine-free diet is safe and may boost the body's immune response against tumors.
The study has two phases. The first phase (6 patients) tests the safety of the diet. The second phase (134 patients) randomly assigns participants to receive either the arginine-free diet plus standard chemoradiotherapy or standard chemoradiotherapy alone.
The arginine-free diet is provided as a liquid nutritional formula for 4 weeks. The main goal is to see if the diet increases the complete response rate (tumor disappearance). We will also evaluate survival outcomes, side effects, and quality of life.
Signed written informed consent prior to any study-related procedures.
Male or female, aged 18 to 80 years.
Locally advanced mid-low rectal cancer staged as cT3, cT4, or node-positive by rectal MRI.
ECOG performance status 0-1.
Stage I or IV rectal cancer.
Cognitive impairment or psychiatric disorders that interfere with understanding the study content.
Central nervous system or meningeal metastases.
Clinically symptomatic moderate or severe ascites (requiring therapeutic paracentesis within 2 weeks before starting study treatment; patients with minimal asymptomatic ascites on imaging may be enrolled).