A B S T R A C T PurposeAlthough chemoradiotherapy plus resection is considered standard treatment for operable rectal carcinoma, the optimal time to administer this therapy is not clear. The NSABP R-03 (National Surgical Adjuvant Breast and Bowel Project R-03) trial compared neoadjuvant versus adjuvant chemoradiotherapy in the treatment of locally advanced rectal carcinoma. Patients and MethodsPatients with clinical T3 or T4 or node-positive rectal cancer were randomly assigned to preoperative or postoperative chemoradiotherapy. Chemotherapy consisted of fluorouracil and leucovorin with 45 Gy in 25 fractions with a 5.40-Gy boost within the original margins of treatment. In the preoperative group, surgery was performed within 8 weeks after completion of radiotherapy. In the postoperative group, chemotherapy began after recovery from surgery but no later than 4 weeks after surgery. The primary end points were disease-free survival (DFS) and overall survival (OS). ResultsFrom August 1993 to June 1999, 267 patients were randomly assigned to NSABP R-03. The intended sample size was 900 patients. Excluding 11 ineligible and two eligible patients without follow-up data, the analysis used data on 123 patients randomly assigned to preoperative and 131 to postoperative chemoradiotherapy. Surviving patients were observed for a median of 8.4 years. The 5-year DFS for preoperative patients was 64.7% v 53.4% for postoperative patients (P ϭ .011). The 5-year OS for preoperative patients was 74.5% v 65.6% for postoperative patients (P ϭ .065). A complete pathologic response was achieved in 15% of preoperative patients. No preoperative patient with a complete pathologic response has had a recurrence. ConclusionPreoperative chemoradiotherapy, compared with postoperative chemoradiotherapy, significantly improved DFS and showed a trend toward improved OS.

Purpose The optimal chemotherapy regimen administered concurrently with preoperative radiation therapy (RT) for patients with rectal cancer is unknown. National Surgical Adjuvant Breast and Bowel Project trial R-04 compared four chemotherapy regimens administered concomitantly with RT. Patients and Methods Patients with clinical stage II or III rectal cancer who were undergoing preoperative RT (45 Gy in 25 fractions over 5 weeks plus a boost of 5.4 Gy to 10.8 Gy in three to six daily fractions) were randomly assigned to one of the following chemotherapy regimens: continuous intravenous infusional fluorouracil (CVI FU; 225 mg/m2, 5 days per week), with or without intravenous oxaliplatin (50 mg/m2 once per week for 5 weeks) or oral capecitabine (825 mg/m2 twice per day, 5 days per week), with or without oxaliplatin (50 mg/m2 once per week for 5 weeks). Before random assignment, the surgeon indicated whether the patient was eligible for sphincter-sparing surgery based on clinical staging. The surgical end points were complete pathologic response (pCR), sphincter-sparing surgery, and surgical downstaging (conversion to sphincter-sparing surgery). Results From September 2004 to August 2010, 1,608 patients were randomly assigned. No significant differences in the rates of pCR, sphincter-sparing surgery, or surgical downstaging were identified between the CVI FU and capecitabine regimens or between the two regimens with or without oxaliplatin. Patients treated with oxaliplatin experienced significantly more grade 3 or 4 diarrhea (P < .001). Conclusion Administering capecitabine with preoperative RT achieved similar rates of pCR, sphincter-sparing surgery, and surgical downstaging compared with CVI FU. Adding oxaliplatin did not improve surgical outcomes but added significant toxicity. The definitive analysis of local tumor control, disease-free survival, and overall survival will be performed when the protocol-specified number of events has occurred.

Activation of the tyrosine kinase of the c-src gene product, pp6Ot'U, has been shown to occur in nearly every primary colorectal carcinoma, and is found as early as in polyps of high malignant potential. However, no studies have addressed potential pp60CsDC changes which occur during progression. To examine this question, we have studied kinase activity and protein levels in 7 colonic polyps, 19 primary lesions, and 19 liver metastases relative to normal colonic mucosa. Significant increases in tyrosine kinase activity were seen as early as in colonic polyps of high malignant potential. Further increases were observed in activity and level in primary tumors. However, the greatest increases in activity and protein levels were observed in liver metastases. Additionally, six metastatic lesions were obtained in which synchronous primary tumor was resected. In each of these liver metastases, pp60"$ activity and level were significantly increased relative to the corresponding primary tumor, as well as to normal colonic mucosa. Our results demonstrate that progression of colon primary tumors to liver metastases correlates with increased pp6O 5rc kinase activity and protein level. (J. Clin. Invest. 1993. 91:53-60.)

Continuous infusion 5-FU produced outcomes for local-regional control, DFS, and OS similar to those obtained with oral capecitabine combined with radiation. This study establishes capecitabine as a standard of care in the pre-operative rectal setting. Oxaliplatin did not improve the local-regional failure rate, DFS, or OS for any patient risk group but did add considerable toxicity.