Study: Give Herceptin at Same Time as Chemo Dec. 15, 2009 (San Antonio) -- In findings that have been eagerly awaited by women with breast cancer and their doctors, researchers report that the breast cancer drug Herceptin should be given at the same time as chemotherapy, not after chemotherapy is concluded.

"Giving the drugs concurrently instead of sequentially results in an additional 8,000 women with HER2-positive cancer in the U.S. being alive and without disease each year," Edith Perez, MD, of the Mayo Clinic tells WebMD.

About 20% of breast cancer patients have HER2-positive cancers -- tumors that have too much of a type of the HER2 protein. Herceptin binds to and blocks HER2 receptors that appear on the surface of some breast cancer cells.

Compared with chemo alone, giving Herceptin after chemo cuts the chance that cancer will come back within five years by about one-third, Perez says.

Giving Herceptin and chemo together slashes the risk of recurrence by an additional one-fourth, she says. "It's a huge gain."

Both the concurrent and sequential methods of giving the drugs are approved by the FDA, and most U.S. doctors already give the drugs together, says Claudine Isaacs, MD, a breastcancer specialist at the Georgetown Lombardi Comprehensive Cancer Center in Washington, D.C.

But in Europe and elsewhere, doctors tend to give Herceptin after chemotherapy has ended, she says. As a result, the findings have been eagerly awaited, Isaacs says.

She moderated a news briefing at which the results were presented at the annual San Antonio Breast Cancer Symposium.

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