Efficacy of preoperative concurrent chemoradiotherapy in treatment of locally advanced middle-low rectal cancer / 中华放射肿瘤学杂志

ABSTRACT

Objective To evaluate the efficacy and tolerance of preoperative concurrent chemoradiotherapy in the treatment of locally advanced middle-low rectal cancer.Methods From June 2007 to June 2013,51 untreated patients with histopathologically proven rectal cancer (T3/T4 or N (+))were included in this study.Three-dimensional radiotherapy was delivered to the whole pelvic cavity at 45.0-50.4 Gy/25-28 fractions.Two cycles of chemotherapy with FOLFOX4 or XELOX were given concurrently at weeks 1 and 4 of radiotherapy.Surgery was performed at 4-8 weeks after chemoradiotherapy.Adjuvant chemotherapy with FOLFOX4 or XELOX was given within one month after surgery.The Kaplan-Meier method was used to calculate survival rates,and the log-rank test was used for univariate analysis;the Cox regression model was used for multivariate prognostic analysis.Results Fortynine patients completed the preoperative chemoradiotherapy and surgery.The median follow-up was 2.9 years.The overall sphincter preservation rate was 65％;the overall downstaging rate was 59％.Ten (20.4％) of all patients achieved a pathologic complete response (pCR).Grade ≥3 toxicities occurred in 25％ of all patients,and the overall postoperative complication rate was 31％.The 3-and 5-year sample sizes were 24,12,respectively.The 3-and 5-year overall survival rates were 81％ and 69％,respectively;the 3-and 5-year disease-free survival (DFS) rates were 76％ and 60％,respectively;the 3-and 5-year local recurrence-free survival (LRFS) rates were 78％ and 70％,respectively;the distant metastasis-free survival rates were 82％ and 74％,respectively.The multivariate analysis showed that tumor downstaging was an independent prognostic factor for 5-year DFS and LRFS.Conclusions For locally advanced middle-low rectal cancer,preoperative radiotherapy with concurrent FOLFOX4/XELOX chemotherapy can increase pathologic downstaging rate,pCR rate,and sphincter preservation rate.Patients with tumor downstaging may have a better survival advantage.