Radiation Therapy and Chemotherapy Followed by Surgery and Combination Chemotherapy in Treating Patients With Rectal Cancer

OBJECTIVES: I. Determine the local recurrence rate, disease-free survival, and overall survival of patients with stage II or III rectal cancer treated with neoadjuvant radiotherapy and fluorouracil followed by surgical resection and adjuvant fluorouracil and leucovorin calcium. II. Determine the toxicity rate in patients treated with this regimen. III. Correlate failure-free survival with ultrasound-determined preoperative staging in patients treated with this regimen. IV. Determine the quality of life of patients treated with this regimen. V. Determine if toxicity due to treatment, daily stool frequency, sexual dysfunction, and disease-free survival correlates with quality of life parameters in patients treated with this regimen. VI. Correlate clinical selection criteria with ability to perform sphincter-sparing surgery in patients treated with this regimen. VII. Determine post-chemoradiotherapy pathological response, margin status, and lymph node status and correlate these factors with initial clinico-pathologic findings in patients treated with this regimen. OUTLINE: Patients undergo pelvic radiotherapy once daily five days a week for 5 weeks followed by boost radiotherapy twice daily for 7 days. Patients also receive neoadjuvant fluorouracil IV continuously over days 1-4 and 36-40. Patients undergo surgical resection 4-6 weeks after completion of radiotherapy. At 4 weeks after surgery, patients receive adjuvant leucovorin calcium IV and fluorouracil IV once daily five days a week. Treatment continues every 4 weeks for 4 courses in the absence of disease progression or unacceptable toxicity. Quality of life is assessed at baseline, at the completion of pelvic and boost radiotherapy, at 4 weeks after completion of chemoradiotherapy (prior to surgery), and then at 3, 6, and 12 months after completion of study therapy. Patients are followed every 3 months for 2 years, every 4 months for 3 years, and then annually thereafter. PROJECTED ACCRUAL: A total of 23-41 patients will be accrued for this study.