Capecitabine, Panitumumab, and Radiation Therapy With or Without Irinotecan Hydrochloride in Treating Patients Undergoing Surgery for Localized Rectal Cancer

Overview

RATIONALE: Drugs used in chemotherapy, such as capecitabine and irinotecan hydrochloride, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Monoclonal antibodies, such as panitumumab, can block tumor growth in different ways. Some block the ability of tumor cells to grow and spread. Others find tumor cells and help kill them or carry tumor-killing substances to them. Radiation therapy uses high-energy x-rays to kill tumor cells. Giving chemotherapy, monoclonal antibody therapy, and radiation therapy before surgery may make the tumor smaller and reduce the amount of normal tissue that needs to be removed. PURPOSE: This phase II trial is studying the side effects of giving capecitabine and panitumumab together with radiation therapy with or without irinotecan hydrochloride and to see how well it works in treating patients undergoing surgery for localized rectal cancer.

OBJECTIVES: Primary * To assess the pathological tumor response rate in patients with localized rectal cancer treated with neoadjuvant chemoradiotherapy comprising capecitabine, panitumumab, and radiotherapy with or without irinotecan hydrochloride. * To assess the incidence of grade 3/4 toxicity during neoadjuvant chemoradiotherapy. Secondary * To assess the disease-free survival. * To assess the time to treatment failure. * To assess the1-year and 2-year survival rates. * To assess local recurrence, defined as recurrence in pelvis at the site of previous disease. * To assess the safety and toxicity grade using NCI CTCAE v3.0 criteria. * To assess the number and percentage of patients who undergo down staging of their disease as determined before initiating neoadjuvant therapy and at the time of surgery. * To assess the number and percentage of patients where permanent colostomy can be avoided as determined by the surgeon before initiating neoadjuvant therapy and at the time actual surgery is performed. OUTLINE: This is a multicenter study. * Phase A: Patients undergo radiotherapy once daily 5 days a week and receive oral capecitabine twice daily 5 days a week for 5½ weeks. Patients also receive panitumumab IV over 1 hour on days 1, 15, and 29 during radiotherapy in the absence of disease progression or unacceptable toxicity. * Phase B: Patients undergo radiotherapy and receive capecitabine and panitumumab as in Phase A. Patients also receive irinotecan hydrochloride IV on days 1, 8, 22, and 29 in the absence of disease progression or unacceptable toxicity. Patients undergo surgery 6-8 weeks after completion of chemoradiotherapy, After completion of study treatment, patients are followed up every 3 months for 1 year and then every 6 months thereafter.