Combining the molecularly targeted therapy Herceptin with chemotherapy in women with early stage breast cancer significantly improves disease-free survival for patients with a specific genetic mutation that results in very aggressive disease, a top UCLA researcher reported Thursday.
Dr. Dennis Slamon, whose laboratory and clinical research lead to the development of Herceptin, reported results of the Phase III study of more than 3,200 women Thursday at the 29th annual San Antonio Breast Cancer Symposium.
The three-armed study compared the standard therapy of Adriamycin and Carboplatin followed by Taxotere (ACT), an experimental regimen of Adriamycin and Carboplatin followed by Taxotere and one year of Herceptin (ACTH), and an experimental regimen of Taxotere and Carboplatin with one year of Herceptin (TCH).
The study tested Herceptin with and without Adriamycin, an anthracycline commonly used to treat breast cancer but one that, when paired with Herceptin, can cause permanent heart damage. Researchers wanted to determine whether they could provide a therapy as effective as ACTH without the resulting cardiac problems. The study, Slamon said, showed that the women who did not receive Adriamycin did just as well as those who did, and they experienced a five-fold decrease in significant heart toxicities compared to those who got Adriamycin. Also, some women in the ACTH arm developed leukemias, while none of the women on the non-Adriamycin arm did, Slamon said.
"This study demonstrates unequivocally that the best treatment for early stage HER-2 positive breast cancer is obtained with a non-anthracycline regimen, TCH, that avoids the significant cardiac damage found when Adriamycin is used with Herceptin," said Slamon, director of clinical/translational research at UCLAs Jonsson Cancer Center. "This trial should impact the way early stage breast cancer is treated, with TCH being considered the preferred option."