Pathologic complete response of primary tumor following preoperative chemoradiotherapy for locally advanced rectal cancer. Long-term outcomes and prognostic significance of pathologic nodal status (KROG 09-01)

摘要

Objective: To investigate long-term outcomes of locally advanced rectal cancer (LARC) patients with postchemo-radiotherapy (post-CRT) pathologic complete response of primary tumor (ypT0) and determine prognostic significance of post-CRT pathologic nodal (ypN) status. Background: LARC patients with post-CRT pathologic complete response were suggested to have favorable long-term outcomes, but prognostic significance of ypN status has never been specifically defined in ypT0 patients. Methods: The Korean Radiation Oncology Group collected clinical data for 333 LARC patients with. ypTO following preoperative CRT and curative radical resections between 1993 and 2007. Sphincter preservation surgery and abdominoperineal resection were performed in 283 (85.0%) and 50 (15.0%) patients, respectively. Postoperative chemotherapy was given to 285 (85.6%) patients. Survival was estimated by the Kaplan-Meier method, and the Cox proportional hazard model was used in multivari-ate analyses.