Is not undergoing surgery a safe treatment option in rectal cancer treatment?

This study investigated the outcomes of rectal cancer patients with complete or near-complete response to chemotherapy and radiation therapy (CRT) who do not undergo surgery. Researchers reported that not undergoing surgery, in selected patients, is a safe option for treatment of rectal cancer. 

The standard treatment for locally advanced rectal cancer is CRT followed by surgery.  In up to 15-20% of the patients no tumor is detected after CRT. It has been suggested that in selected patients, with the proper follow-up method, not undergoing surgery or undergoing an endoscopic surgery is a safe treatment option. Endoscopic surgery is a less invasive surgery involving a tube with a light, video camera and other surgical instruments inserted through the anus. A prior study reported an overall survival of 100% in rectal cancer patients with complete response to CRT who did not undergo surgery. However, this study involved a small number of patients and a short follow-up period. 

The objective of this study was to investigate the long-term outcomes of rectal cancer patients with complete response to CRT who did not undergo surgery or near-complete response selected for endoscopic surgery. This study included 100 patients with locally advanced rectal cancer who underwent CRT. 61 patients had a complete response and 39 had a near-complete response of whom 15 underwent endoscopic surgery. The average follow-up period was 41.1 months. 

15 patients developed a local regrowth of their tumor within 25 months. The 3-year overall survival (absence of death by any cause) was 96.6%. The 3-year distant metastasis-free survival (absence of tumor spread to other organs) was 96.8%. 3-year local regrowth-free survival (time until tumor regrows locally) was 84.6%. 3-year disease-free survival (absence of regrowth, distant metastasis, and death by any cause) was 80.6%.

This study determined that not undergoing surgery after a CRT complete response is a safe treatment option for selected rectal cancer patients.