Cancer vaccine shows promise in tests

Cancer vaccine shows promise in tests

Treatment uses the body's immune system to battle the disease

MARILYNN MARCHIONE / Associated Press

Orlando, Fla. -- First there was surgery, then chemotherapy and radiation. Now, doctors have overcome 30 years of false starts and found success with a fourth way to fight cancer: using the body's natural defender, the immune system. The approach is called a cancer vaccine, but it treats the disease rather than prevents it.

At a cancer conference Sunday, researchers said one such vaccine kept a common form of lymphoma from worsening for more than a year.

Experimental vaccines against three other cancers -- prostate, the deadly skin disease melanoma and an often fatal childhood tumor called neuroblastoma -- also gave positive results in late-stage testing.

"I don't know what we did differently to make the breakthrough," said Dr. Len Lichtenfeld of the American Cancer Society.

Instead of a single "Aha!" moment, there have been many "ah, so" discoveries about the immune system that now seem to be paying off, said Dr. John Niederhuber, director of the National Cancer Institute.

It's way too soon to declare victory. No one knows how long the benefits will last, whether people will need "boosters" to keep their disease in check or whether vaccines will ever be a cure. Many vaccines must be custom-made for each patient. How practical will that be, and what will it cost?

Those are all good questions -- but there are no answers yet, said Dr. Richard Schilsky, a University of Chicago cancer specialist and American Society of Clinical Oncology president.

Several vaccine studies were reported over the weekend at the oncology group's annual meeting in Florida.

Dr. Stephen Schuster of the University of Pennsylvania School of Medicine led a study testing BiovaxID, an experimental vaccine against follicular lymphoma developed by the National Cancer Institute. Researchers gave 41 patients a shellfish protein and an immune booster; 76 other patients were given those plus the vaccine. After nearly five years of follow-up, the average time until the cancer worsened was 44 months in the vaccine group and 30 months in the others.

Big gains also were seen with a neuroblastoma vaccine developed by the cancer institute. In a study of 226 patients, 86 percent of vaccine recipients were still alive after two years versus 75 percent of others not given the vaccine. The benefits from a melanoma vaccine extended the time until patients relapsed -- three months versus 1 1/2 for those not given the vaccine.