Researchers are now saying that chemotherapy with drugs called aromatase inhibitors is unnecessary after lumpectomy, radiation and 5 years of Tamoxifen, for the vast majority of women with breast cancer.
In a report delivered at the annual meeting of the American Society for Therapeutic Radiation and Oncology in Denver, principal researcher Dr. Gary Freedman, of Fox Chase Cancer Center in Philadelphia, presented the results of a study which involved 471 women diagnosed with breast cancer.
All had undergone lumpectomies and received radiation and 5 years of Tamoxifen, and in the group 152 women also received chemotherapy with aromatase inhibitors.
The study group were analyzed to determine which women benefited from the addition of chemotherapy.
Freedman and colleagues found that women who were disease-free 5 years after surgery, radiation and Tamoxifen had just a 2.5 percent risk of their cancer returning at 10-year follow-up.
According to Freedman in clinical practice, a benefit level of greater than 3 percent is commonly used to select patients for chemotherapy, and assuming a 40 percent reduction in the risk of the cancer returning, by adding an aromatase inhibitor to 5 years of Tamoxifen therapy, the absolute benefit would occur in 1 percent of patients.
Freedman does say however that some women may benefit from chemotherapy, for example those who are premenopausal, have cancer in several lymph nodes, or have major diseases in addition to their cancer.