Radiation Oncology/Rectum/NSABP trials

Radiation Oncology/Rectum

The National Surgical Adjuvant Breast and Bowel Project (NSABP):

See other NSABP trials and NSABP Colon trials
See the NSABP web page.

• R-01 (1977-86) - Dukes' B and C. After resection, randomized to observation, MOF chemotherapy, or RT.
  • Results 1988: PMID 3276900
  • PMID 3532972 (1986 - "An analysis of survival and treatment failure following abdominoperineal and sphincter-saving resection in Dukes' B and C rectal carcinoma.")
  • PMID 3516601 (1986 - "A comparison of stapled and handsewn anastomoses in patients undergoing resection for Dukes' B and C colorectal cancer.")
  • PMID 3511864 [Full text at PMC] - NSABP C-01 and R-01 - (1986 - "The prognostic value of the modifications of the Dukes' C class of colorectal cancer.")
  • PMID 6722730 (1984 - "The relationship of depth of penetration and tumor size to the number of positive nodes in Dukes C colorectal cancer.")
  • PMID 6337699 (1983 - "Tumor size and regional lymph node metastasis in colorectal cancer. A preliminary analysis from the NSABP clinical trials.")

• R-02 (1987-92) - Dukes' B and C. Randomized to post-op chemo/RT or post-op chemotherapy alone.
  • 2000: PMID 10699069 - Post op chemo/RT did not improve DFS or OS. 5-FU/LV chemo was superior to MOF (a second randomization).

• R-03 (1993-99) - PMID 19770376 Full text — "Preoperative multimodality therapy improves disease-free survival in patients with carcinoma of the rectum: NSABP R-03." Roh M et al. J Clin Oncol. 2009 Nov 1;27(31):5124-30. Epub 2009 Sep 21.
  • Trial closed due to poor accrual - intended sample size was 900 patients. Results analyzed as below.
  • 267 pts. with T3-T4 or N+ rectal cancer. Randomized to preoperative or postoperative chemoradiotherapy (45 Gy in 25 fx with 5.4 Gy boost, chemo consisting of 5-FU and leucovorin).
  • 5-year DFS was improved for pre-op over post-op (64.7% v 53.4%, p=0.011). Nonsignificant trend in 5-year OS (74.5% v 65.6%, p=0.065). No difference in locoregional recurrence, 10.7% in each group.
  • Conclusion: Pre-op chemoradiotherapy, compared with post-op chemoradiotherapy, significantly improved DFS and showed a trend toward improved OS.

• R-04 (2004- 2010) - pre-operative chemo/RT with continuous infusion 5-FU vs Capecitabine (Xeloda) vs Capecitabine +Oxaliplatin vs 5-FU + Oxaliplatin
  • Abstract ASCO 2011 [1]
  • 1608 pts. with clinical stage II or III rectal cancer, pre-operative chemo/RT (45 Gy in 25 fx with 5.4 -10.8 Gy boost), 4 arm randomization to chemo with arm A) 5-FU (CVI 225mg/m2 5 days/wk) arm B) 5-FU + Oxaliplatin (50mg/m2/wk x 5) arm C) Capecitabine (825 mg/m2 BID 5 days/wk) arm D) Capecitabine + Oxaliplatin
  • Endpoints: complete pathologic response (pCR), sphincter-saving surgery (SSS), surgical downstaging (SD, conversion to SSS).
  • pCR 5-FU +/-OX 18.8 % vs. CAPE +/-OX 22.2 % (NS), SSS 61.2 % vs. 62.7 % (NS), SD 20.7 % vs. 23.0 % (NS), grade 3/4 diarrhoe 11.2 % vs. 10.8 % (NS)
  • pCR (5-FU or CAPE) No OX 19.1 % vs. (5-FU or CAPE) + OX 20.9 % (NS), SSS 63.6 % vs. 60.4 % (NS), SD 23.0 % vs. 19.2 % (NS), grade 3/4 diarrhoe 6.6 % vs. 15.4 % (SS)
  • Conclusion: no significant differences in pCR, SSS, SD between groups with 5-FU and Capecitabine or between groups with or without Oxaliplatin, but increased grade 3/4 gastrointestinal toxicity with addition of Oxaliplatin
  • 2014 GI symposium presentation [2]: Standard of care should be Capecitabine + 50-55.8 Gy Radiation preoperatively. No benefit seen with addition of Oxaliplatin.