Findings may keep tumors at bay

Medicine is opening up new lines of attack in a crucial area of cancer care: preventing tumors from coming back.

Researchers have reported that a strict low-fat diet can lower the risk of recurrence among breast-cancer patients. Another study suggested that aspirin use may improve the odds of survival for colon-cancer patients who also receive standard postsurgical chemotherapy.

The new findings, presented at the annual meeting of the American Society of Clinical Oncology in Orlando, Fla., offer some hope in confronting one of the stubborn realities of cancer treatment. While advances in the early detection and treatment of tumors have led to lower death rates from diseases such as lung, breast and colon cancer, many tumors regrow and spread months or years after surgery. That is because the original tumor often sheds microscopic clusters of cells that survive the initial treatment.

Preventing recurrence is especially critical given the way cancer specialists increasingly view the concept of a cure for the disease. Instead of a one-time victory over cancer, a cure is likely to be the result of a longer process: Find tumors early, take them out via a combination of surgery, radiation and drug treatment — and then prevent them from coming back.

Several other studies presented over the weekend also addressed the issue of tumor recurrence. Among the findings were indications that some cancer treatments, including the targeted biotechnology drug Herceptin and an osteoporosis drug called Femara, may also be useful weapons against recurring breast tumors.

While oncologists are heartened by the new findings, many stress that the battle against recurring tumors will continue. Gabriel Hortobagyi, a cancer researcher at the M.D. Anderson Cancer Center in Houston, notes that advances over the past several years have reduced the risk of death from breast cancer by 60 percent to 65 percent, and that adding drugs like Herceptin may reduce the risk by as much as 80 percent.

"We are getting much better," Hortobagyi says. "But it's not enough until we reach 100 percent."

The most immediate impact on existing treatment is likely to come from the Herceptin trial, which demonstrated that the drug can reduce the recurrence of certain particularly aggressive breast-cancer tumors by 52 percent when added to standard chemotherapy following surgery.