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Name of the Trial

Phase II Study of Treatment Selection Based Upon Tumor Thymidylate Synthase Expression in Previously Untreated Patients With Metastatic Colorectal Cancer (ECOG-E4203). See the protocol summary ³.

Principal Investigators

Dr. Neal J. Meropol and Dr. Jean Grem, Eastern Cooperative Oncology Group.

Dr. Neal J. Meropol Principal Investigator

Why This Trial Is Important

A number of treatments for metastatic colorectal cancer have been approved over the past few years, but doctors want to determine which treatments will work best in individual patients.

The drug fluorouracil (5-FU) is often used to treat colorectal cancer; however, previous clinical studies suggest that tumors with a high level of the protein thymidylate synthase (TS) are more likely to be resistant to 5-FU treatment.

In this trial, researchers will measure the level of TS in the tumors of patients with metastatic colorectal cancer. Patients whose tumors show a low level of TS will be treated with combination chemotherapy consisting of 5-FU, leucovorin calcium, and oxaliplatin (the so-called "FOLFOX" regimen) plus the monoclonal antibody bevacizumab. Patients whose tumors show a high level of TS will be treated either with the same drug combination plus bevacizumab or with an investigational combination of the drugs oxaliplatin and irinotecan plus bevacizumab. Researchers want to determine whether replacing 5-FU and leucovorin calcium with irinotecan will lead to better response rates and survival in these patients.

"As the array of treatments for metastatic colorectal cancer expands, it's important to match specific treatments with those patients who are most likely to benefit from them," said Dr. Meropol. "This is the first national study for patients with metastatic colorectal cancer to prospectively assign treatment based on the molecular characteristics of the tumor."

Who Can Join This Trial

Researchers will enroll 246 patients with metastatic or locally recurrent colorectal cancer. See the list of eligibility criteria ⁴. This clinical trial is eligible for special Medicare coverage ⁵.

Study Sites and Contact Information

Study sites in the United States are recruiting patients for this trial. See the list of study contacts ⁶ or call the NCI's Cancer Information Service at 1-800-4-CANCER (1-800-422-6237) for more information. The toll-free call is confidential.

Glossary Terms

A drug used to treat several types of cancer, including certain types of colorectal, lung, breast, and kidney cancers and glioblastoma. It is also being studied in the treatment of other types of cancer. Bevacizumab binds to vascular endothelial growth factor (VEGF) and may prevent the growth of new blood vessels that tumors need to grow. It is a type of antiangiogenesis agent and a type of monoclonal antibody. Also called Avastin.

A drug used to treat symptoms of cancer of the colon, breast, stomach, and pancreas. It is also used in a cream to treat certain skin conditions. Fluorouracil stops cells from making DNA and it may kill cancer cells. It is a type of antimetabolite. Also called 5-fluorouracil and 5-FU.

The active ingredient in a drug used alone or in combination with other drugs to treat colon cancer or rectal cancer that has spread to other parts of the body or has come back after treatment with fluorouracil. It is also being studied in the treatment of other types of cancer. Irinotecan blocks certain enzymes needed for cell division and DNA repair, and it may kill cancer cells. It is a type of topoisomerase inhibitor and a type of camptothecin analog.

The active ingredient in a drug used to lessen the toxic effects of substances that block the action of folic acid, especially the anticancer drug methotrexate. Leucovorin is used to treat some types of anemia and is also used together with fluorouracil to treat colorectal cancer. It is also being studied in the treatment of other types of cancer and other conditions. Leucovorin is a form of folic acid. It is a type of chemoprotective agent and a type of chemosensitizing agent. Also called folinic acid.

Having to do with metastasis, which is the spread of cancer from the primary site (place where it started) to other places in the body.

A drug used together with other drugs to treat colorectal cancer that is advanced or has come back. It is also being studied in the treatment of other types of cancer. Oxaliplatin attaches to DNA in cells and may kill cancer cells. It is a type of platinum compound. Also called Eloxatin.

The percentage of patients whose cancer shrinks or disappears after treatment.