New Drugs, New Combinations Fight Breast Cancer

ByABC News
December 11, 2009, 4:23 PM

Dec. 12 -- FRIDAY, Dec. 11 (HealthDay News) -- New therapies and new spins on existing treatments are offering hope for patients with breast cancer, especially those with metastatic disease, according to research being presented this week at the annual San Antonio Breast Cancer Symposium in San Antonio, Texas.

One study found that a higher (500-milligram) dose of Faslodex (fulvestrant) works better than the currently approved 250-milligram dose in hormone receptor-positive breast tumors that had already spread to other parts of the body. There was no difference in the severity of side effects between the two doses, researchers added.

Many breast cancer cells are sensitive to circulating estrogen because they carry receptors on their surface that link up with the hormone, helping malignant cells to spread and grow. Faslodex targets this critical link-up.

"This drug is different from other hormonal agents. It can actually destroy the estrogen receptor," explained study lead author Dr. Angelo Di Leo, director of the department of oncology at the Hospital of Prato in Italy. "Evidence from past clinical trials suggests that if you increase the dose of the drug you can induce a more profound down-regulation of the estrogen receptor."

And, in the new trial, that turned out to be the case.

"It was clear that 500 milligrams was more effective than 250 in prolonging time to disease progression and the median time to progression, which was 6.5 months for those in the 500-milligram group versus 5.5 months in the 250-milligram group," she said.

There was no evidence of tumor shrinkage but there was a hint that survival was also improved, but this was not statistically significant.

Dr. C. Kent Osborne, president of the symposium and moderator of a Friday teleconference detailing these and other findings, and director of the Dan L. Duncan Cancer Center and the Lester and Sue Smith Breast Center at Baylor College of Medicine in Houston, expressed hope that the dosing changes may also help women with early breast cancer.