Correspondence: Jin Hee Kim, MD, PhD, Department of Radiation Oncology, Dongsan Medical Center, ... Young Ki Oh, PhD2, Sung Gyu Baek, MD, PhD3.
Original Article Radiat Oncol J 2016;34(2):106-112 http://dx.doi.org/10.3857/roj.2015.01585 pISSN 2234-1900 · eISSN 2234-3156
Predictors of pathologic complete response after preoperative concurrent chemoradiotherapy of rectal cancer: a single center experience Euncheol Choi, MD1, Jin Hee Kim, MD, PhD2, Ok Bae Kim, MD, PhD2, Mi Young Kim, MD2, Young Ki Oh, PhD2, Sung Gyu Baek, MD, PhD3 1
Proton Therapy Center, National Cancer Center, Goyang; Departments of 2Radiation Oncology and 3Colorectal Surgery, Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Korea
Purpose: To identify possible predictors of pathologic complete response (pCR) of rectal cancer after preoperative concurrent chemoradiotherapy (CCRT). Materials and Methods: We conducted a retrospective review of 53 patients with rectal cancer who underwent preoperative CCRT followed by radical surgery at a single center between January 2007 and December 2012. The median radiotherapy dose to the pelvis was 54.0 Gy (range, 45.0 to 63.0 Gy). Five-fluorouracil-based chemotherapy was administered via continuous infusion with leucovorin. Results: The pCR rate was 20.8%. The downstaging rate was 66%. In univariate analyses, poor and undifferentiated tumors (p = 0.020) and an interval of ≥7 weeks from finishing CCRT to surgery (p = 0.040) were significantly associated with pCR, while female gender (p = 0.070), initial carcinoembryonic antigen concentration of 5 36 (100) 4 (22.2) 14 (77.8) Circumference (%) 5 22 (100) 3 (13.6) 19 (86.4) Unknown 1 (100) 1 (100) 0 (0) Elevation of CEA level Elevation 27 (100) 4 (16.0) 21 (84.0) No elevation 25 (100) 6 (22.2) 21 (77.8) Unknown 1 (100) 1 (100) 0 (0) Initial Hb level (g/mL)