The metabolic response using 18F-fluorodeoxyglucose-positron emission tomography/computed tomography and the change in the carcinoembryonic antigen level for predicting response to pre-operative chemoradiotherapy in patients with rectal cancer

The post-CRT SUVmax and SRR are potential factors for predicting tumor response in pre-operative CRT. The patients with lower post-CRT SUVmax and higher SRR could be expected to achieve maximum tumor regression after pre-operative CRT in this study.