J Korean Soc Ther Radiol Oncol.  2011 Mar;29(1):11-19. 10.3857/jkstro.2011.29.1.11.

The Pathological and Clinical Effects of Preoperative Chemoradiation in Rectal Cancer

• Song JH
• Jang HS
• Kim YS
• Chung SM
• Son SH
• Kang JH
• Youk EG
• Lee DS
• Lee SH
• Yoon SC

• KMID: 2097248
• DOI: http://doi.org/10.3857/jkstro.2011.29.1.11

Abstract

PURPOSE
To evaluate the pathological and clinical effects of preoperative chemoradiation (CCRT) in cases of locally advanced rectal cancer and to determine the predictive factors for tumor downstaging.
MATERIALS AND METHODS
From March 2004 to August 2008, 33 patients with locally advanced rectal cancer were treated with preoperative CCRT. Twenty-eight patients (84.8%) were treated using a concomitant boost technique while five (15.2%) patients were treated using a cone down boost technique. All patients received 50.4 Gy of irradiation and concurrent chemotherapy with 5-fluorouracil. The median follow-up duration was 24.2 months (range, 9.8 to 64.7 months).
RESULTS
Thirty-one (93.9%) patients underwent surgery. Twenty-four patients (72.7%) underwent anal sphincter-preserving surgery. The 3-year disease free survival (DFS) and overall survival rates were 63.4% and 78.8%, respectively. Post-operative factors were more important for DFS. Pathologic N stage, margin status, and pathologic differentiation were significant prognostic factors (p=0.001, 0.029, 0.030). Tumor size and lymphovascular invasion were also associated with marginal significance (p=0.081, 0.073). However, only pre-treatment T stage was a significant pre-operative factor (p=0.018). The complete pathological response rate was 9.1%. T-downstaging was observed in ten (30.3%) patients, whereas N-downstaging was found in 24 (72.7%) patients. Pre-treatment T stage and the interval between CCRT and operation were the predictive factors for downstaging in a univariate analysis (p=0.029, 0.027). Pre-treatment carcinoembryogenic antigen was also associated with marginal significance (p=0.068).
CONCLUSION
The survival of rectal cancer patients can be better determined based on post-operative findings. Therefore, pre-operative CCRT for downstaging of the tumor seems to be important. Pre-treatment T stage and the interval between CCRT and operation can be used to predict downstaging.

Keyword

Rectal cancer; Preoperative concurrent chemoradiation; Concomitant boost technique

MeSH Terms

Disease-Free Survival
Fluorouracil
Follow-Up Studies
Humans
Rectal Neoplasms
Survival Rate
Fluorouracil