PRIMARY OBJECTIVES:
I. To evaluate the pathological complete response rate in patients with T3 and T4 rectal cancers when treated preoperatively with capecitabine, oxaliplatin, bevacizumab, and concurrent radiotherapy (XRT).
II. To evaluate the resection rate for T3 and T4 rectal cancers and the expected versus actual type of resection (abdominoperinal resection [APR] vs. low anterior resection [LAR] vs. LAR/coloanal anastomosis).
III. To make preliminary observations of patient survival and patterns of recurrence for this treatment combination.
IV. To gain additional experience regarding the toxicity and tolerability of this preoperative and postoperative regimen.
OUTLINE:
PREOPERATIVE CHEMORADIOTHERAPY: Patients undergo radiotherapy (total dose to the tumor bed was 5040 cGy) once daily (QD) 5 days a week and receive capecitabine 825 mg/m^2 orally (PO) twice daily (BID) 5 days a week for 5.5 weeks. Patients also receive oxaliplatin 50 mg/m^2 intravenously (IV) over 2 hours on days 1, 8, 15, 22, and 29 and bevacizumab 5 mg/kg IV over 30-90 minutes on days 1, 15, and 29 during radiotherapy.
SURGERY: Approximately 6-8 weeks after completion of chemoradiotherapy, patients undergo surgical resection. Patients whose tumors are not completely resected or who have metastatic disease discontinue protocol therapy.
POSTOPERATIVE CHEMOTHERAPY: Approximately 4-12 weeks after surgery, patients receive oxaliplatin IV over 2 hours, leucovorin calcium 400 mg/m^2 IV over 2 hours, and bevacizumab 5 mg/kg IV over 30-90 minutes on day 1. Patients also receive fluorouracil 2400 mg/m^2 IV continuously over 46 hours beginning on day 1. Treatment repeats every 2 weeks for 9 courses in the absence of disease progression or unacceptable toxicity. Patients then receive up to 3 additional courses of leucovorin calcium, fluorouracil, and bevacizumab.
After completion of study treatment, patients are followed up periodically for 10 years.