Clinical Parameters Predicting Pathologic Tumor Response After Preoperative Chemoradiotherapy for Rectal Cancer

• Published in: International journal of radiation oncology, biology, physics Vol. 69; no. 4; pp. 1167 - 1172
• Main Authors: Yoon, Sang Min, M.D, Kim, Dae Yong, M.D, Kim, Tae Hyun, M.D, Jung, Kyung Hae, M.D, Chang, Hee Jin, M.D, Koom, Woong Sub, M.D, Lim, Seok-Byung, M.D, Choi, Hyo Seong, M.D, Jeong, Seung-Yong, M.D, Park, Jae-Gahb, M.D
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 15.11.2007
• Subjects: Adult; Aged; Aged, 80 and over; Analysis of Variance; CARCINOEMBRYONIC ANTIGEN; Carcinoembryonic Antigen - blood; CARCINOMAS; CLASSIFICATION; Combined Modality Therapy; COMBINED THERAPY; Downstaging; Female; Hematology, Oncology and Palliative Medicine; HEMOGLOBIN; Hemoglobin A - analysis; Humans; Male; Middle Aged; MULTIVARIATE ANALYSIS; Neoplasm Staging; PATIENTS; Preoperative chemoradiotherapy; Radiology; RADIOLOGY AND NUCLEAR MEDICINE; Rectal cancer; Rectal Neoplasms - blood; Rectal Neoplasms - drug therapy; Rectal Neoplasms - pathology; Rectal Neoplasms - radiotherapy; RECTUM; Remission Induction; SURGERY; Tumor regression; Rectal cancer; Tumor regression; Preoperative chemoradiotherapy; Downstaging
• ISSN: 0360-3016; 1879-355X
• DOI: 10.1016/j.ijrobp.2007.04.047

Purpose To identify pretreatment clinical parameters that could predict pathologic tumor response to preoperative chemoradiotherapy (CRT) for rectal cancer. Methods and Materials The study involved 351 patients who underwent preoperative CRT followed by surgery between October 2001 and July 2006. Tumor responses to preoperative CRT were assessed in terms of tumor downstaging and tumor regression. Statistical analyses were performed to identify clinical factors associated with pathologic tumor response. Results Tumor downstaging (defined as ypT2 or less) was observed in 167 patients (47.6%), whereas tumor regression (defined as Dworak's Regression Grades 3 or 4) was observed in 103 patients (29.3%) and complete regression in 51 patients (14.5%). Multivariate analysis found that predictors of downstaging were pretreatment hemoglobin level ( p = 0.045), cN0 classification ( p < 0.001), and serum carcinoembryonic antigen (CEA) level ( p < 0.001), that predictors of tumor regression were cN0 classification ( p = 0.044) and CEA level ( p < 0.001), and that the predictor of complete regression was CEA level ( p = 0.004). Conclusions The data suggest that pretreatment CEA level is the most important clinical predictor of pathologic tumor response. It may be of benefit in the selection of treatment options as well as the assessment of individual prognosis.