How long should patients with locally advanced rectal cancer wait between chemoradiotherapy and surgery to achieve the best outcome?

This study evaluated the timing between chemoradiotherapy (CRT) and surgery in patients with locally advanced rectal cancer (LARC). The study found that patients who had surgery more than 10 weeks after CRT had the best outcome.

Rectal cancer is commonly treated with surgery to remove the tumor. LARC is cancer in the rectum that has invaded the connective tissue sheath that surrounds the rectum. Patients with LARC have a high risk of spread of the tumor (metastasis). These patients need additional therapy. Patients with LARC are usually given pre-treatment of chemotherapy and radiotherapy (CRT) to shrink the tumor. Following pre-treatment, patients undergo surgery to remove the rectal tumor.

The time between CRT and surgery is not yet clear.

This study evaluated data from 910 patients with LARC who had CRT followed by surgery. Patients were divided into two groups based on the interval between CRT and surgery. Group 1 had surgery at 10 or fewer weeks after CRT. Group 2 had surgery after more than 10 weeks after CRT. Patients in group 1 received 2.7 cycles of CRT on average. Group 2 received 3.4 cycles of CRT on average. The average follow-up time was 49 months.

20.3% of all patients had a complete removal of tumors. 77.8% of patients in group 1 survived for 5 years without disease recurrence. 86.8% of patients in group 2 survived 5 years without disease recurrence. The overall survival rate was similar for groups 1 and 2 (82.5% vs 84.1%).

4.7% of patients in group 1 and 1.1% of patients in group 2 reported wound infection after surgery. Other surgery complications were reported at a similar rate in all patients.

This study showed that patients with LARC who had surgery more than 10 weeks after CRT had better outcomes.

This study was based on medical records. Patients were given surgery when their surgeon estimated it would be most effective. More research is needed.