Study Supports Use of Adjuvant Chemotherapy for Some Patients With Rectal Cancer
Posted: Thursday, June 28, 2018
For patients who have achieved pathologic complete response after neoadjuvant chemoradiotherapy for resected locally advanced rectal cancer, the use of adjuvant chemotherapy seems to offer an overall survival benefit. In fact, those who had clinical stage T3/T4 and node-positive disease achieved the greatest benefit. These study findings, which were published in JAMA Oncology, are based on a propensity score–matching analysis of a cohort from a large national data set.
“The ultimate decision to offer and deliver [adjuvant chemotherapy] to patients with [pathologic complete response] should be based on a thorough discussion with individual patients considering the preoperative clinical staging, overall health status, potential adverse effects/toxicities, expectations, and actual survival benefit,” revealed Patricio M. Polanco, MD, of The University of Texas Southwestern Medical Center, Dallas, and colleagues.
From the National Cancer Database between 2006 and 2012, a total of 2,764 patients with clinical stage II or III resected rectal adenocarcinoma were identified. They were complete responders to neoadjuvant chemoradiotherapy. Of this group, 741 received adjuvant chemotherapy, and 741 underwent postoperative observation.
Those who received adjuvant chemotherapy lived longer than those who did not. For instance, the 1-year overall survival rate with adjuvant chemotherapy was 99.7% versus 99.2% with observation. Moreover, 3-year and 5-year overall survival rates favored adjuvant chemotherapy over observation as well: 97.1% and 94.7% versus 93.6% and 88.4%, respectively. A subgroup analysis revealed that those with clinical stage T3/T4 and node-positive disease seemed to benefit most from adjuvant chemotherapy (hazard ratio, 0.47); however, the investigators noted that the benefit was not statistically significant in the T/N subgroups.