Dr. Sunil Gandhi, Cancer & Blood Disease, 08/21/12

Colon cancer is the third commonest cancer in the USA. Almost every year, 145,000 patients get colon cancer and 56,000 people die due to it. It can be detected early with a colonoscopy, an easy outpatient test. If detected early, it is highly curable.

Unfortunately, many patients present with late stage and cancer has spread to outside the colon, usually to the liver. This is incurable cancer. Even though it is an incurable cancer, it is highly treatable. A few years ago, we had only one mildly effective treatment and average survival used to be around 8 to 10 months. Now three new chemotherapy drugs and three new targeted therapies are approved by the FDA.

None of the drugs by itself was a home run. In other words, one drug by itself improved survival only by few months at a time. But on aggregate with use of all these drugs appropriately, survival of metastatic colon cancer has almost tripled.

Recently, the FDA approved Aflibercept (Zaltrap) for use in the treatment of metastatic colorectal cancer. This is a new drug. It blocks blood supply to cancer cells. It acts like a sponge to remove the chemical in the blood that stimulates blood supply to cancerous cells. By removing the chemical, cancerous cells do not generate the blood vessels through which nutrition flows to cancer. This causes starvation of cancer. It is easier for chemotherapy to kill these cancer cells, which are starving.

One similar drug called Avastin is already available. We do not know whether the new drug Aflibercept is superior to Avastin or not.

The approval is based on the phase 3 trial named VELOUR (Aflibercept Versus Placebo in Metastatic Colorectal Cancer After Failure of an Oxaliplatin-Based Regimen). In the study, 1,226 patients were randomized to either FOLFIORI (one of the standard chemotherapy regimens in colon cancer) and placebo or FOLFIORI and Afblibercept. The addition of Aflibercept to the FOLFIRI, significantly improved both overall and progression-free survival. Twice as many patients responded in the Aflibercept arm than placebo.

Overall survival was increased from about 12.0 months to 13.5 months. This may seem like a small number but all the advances in colon cancer came as one small step forward. At the end, many such small-appearing advances have tripled survival in stage 4 metastatic colon cancers.

In the past five weeks, the FDA has approved four new drugs in various different cancers. This is remarkable. The research in the cancer field is extremely fast and significant. The NCI (National Cancer Institute) has a long-term goal of making cancer a chronic disease just like diabetes or high blood pressure. We are closer to achieving the goal.

Dr. Sunil Gandhi is a hematologist and oncologist. He is volunteer medical adviser of the Citrus Unit of American Cancer Society. Write to 521 N. Lecanto Highway, Lecanto, FL 34461, email sgandhi@tampabay.rr.com or call 352-746-0707.