Preventive efficacy of hydrocortisone enema for radiation proctitis in rectal cancer patients undergoing short-course radiotherapy: a phase II randomized placebo-controlled clinical trial.

This study aimed to investigate the efficacy of hydrocortisone enema in preventing radiation proctitis in patients with rectal cancer undergoing short-course radiotherapy (SCRT). This phase II randomized controlled trial enrolled patients with newly diagnosed locally advanced rectal cancer (clinically staged T3-4 and/or N1-2M0). Participants received a median of 4 cycles of neoadjuvant chemotherapy (capecitabine plus oxaliplatin) followed by 3-dimensional conformal SCRT (25 Gy in 5 fractions). Patients were randomly assigned to receive either a hydrocortisone enema (n=50) or a placebo (n=51) once daily for 5 consecutive days during SCRT. The primary endpoint was the incidence and severity of acute proctitis. Of the 111 eligible patients, 101 were included in the study. Baseline characteristics, including sex, age, performance status, and tumor location, were comparable across the treatment arms. None of the patients experienced grade 4 acute gastrointestinal toxicity or had to discontinue treatment due to treatment-related adverse effects. Patients in the hydrocortisone arm experienced significantly less severe proctitis (P<0.001), diarrhea (P=0.023), and rectal pain (P<0.001) than those in the placebo arm. Additionally, the duration of acute gastrointestinal toxicity following SCRT was significantly shorter in patients receiving hydrocortisone (P<0.001). Hydrocortisone enema was associated with a significant reduction in the severity of proctitis, diarrhea, and rectal pain compared to placebo. Additionally, patients treated with hydrocortisone experienced shorter durations of gastrointestinal toxicity following SCRT. This study highlights the potential benefits of hydrocortisone enema in managing radiation-induced toxicity in rectal cancer patients undergoing radiotherapy.