Bevacizumab, Radiation Therapy, and Combination Chemotherapy in Treating Patients Who Are Undergoing Surgery for Locally Advanced Nonmetastatic Rectal Cancer

Study Summary

This phase II trial studies how well giving bevacizumab, radiation therapy, and combination chemotherapy works in treating patients who are undergoing surgery for locally advanced nonmetastatic rectal cancer. Monoclonal antibodies, such as bevacizumab, can block tumor growth in different ways. Some find tumor cells and kill them or carry tumor-killing substances to them. Others interfere with the ability of tumor cells to grow and spread. Bevacizumab may also stop the growth of tumor cells by blocking blood flow to the tumor. Radiation therapy uses high-energy x-rays to kill tumor cells. Drugs, such as capecitabine, may make tumor cells more sensitive to radiation therapy. Drugs used in chemotherapy, such as capecitabine, oxaliplatin, fluorouracil, and leucovorin, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Giving bevacizumab together with radiation therapy and combination chemotherapy before surgery may make the tumor smaller and reduce the amount of normal tissue that needs to be removed. Giving bevacizumab together with combination chemotherapy after surgery may kill any tumor cells that remain after surgery.

Primary Outcome

Pathologic complete response to preoperative therapy was determined at the time of surgical resection. Pathologic complete response (pCR) is defined as no evidence of invasive cells on pathologic examination of the primary rectal cancer (or tissue from the area where the tumor had been if there is a complete clinical response). Pathologic complete response rate is calculated as number of patients achieving pathologic complete response divided by all eligible and treated patients

Interventions

• DRUG Capecitabine
• DRUG Fluorouracil
• DRUG Oxaliplatin
• BIOLOGICAL Bevacizumab
• DRUG Leucovorin Calcium