ROCHESTER, N.Y., Dec. 14 /PRNewswire/ -- Data from a new study published in the December 15 issue of the Journal of Clinical Oncology point to an alarming pattern in breast cancer treatment -- more than half of women with early stage breast cancer whose records were evaluated did not receive their full, recommended dose of potentially life-saving chemotherapy.
The comprehensive retrospective analysis found that 56 percent of the 20,799 women being treated for early stage breast cancer in 1,243 community- based oncology practices nationwide received less than 85 percent of their recommended chemotherapy dose intensity as prescribed in the optimal treatment plan due to treatment delays of at least one week (25 percent) or dose reductions (37 percent). Previous studies have demonstrated that receiving less than 85 percent of the recommended dose intensity can result in lower survival rates for women with breast cancer.
The primary cause of chemotherapy delays and dose reductions is neutropenia, a shortage of infection-fighting white blood cells and a common and potentially serious side effect of chemotherapy. Chemotherapy drugs are designed to destroy cancer cells, but unfortunately healthy cells are also killed, including the white blood cells that protect against infection. When a patient’s white blood cell count drops too low, they are at increased risk of developing infections and chemotherapy often has to be delayed until these essential white blood cells are replenished.
“Far too many patients are not receiving the chemotherapy doses they need in order to have the best chance of remission or cure,” said Gary H. Lyman, M.D., M.P.H., of the James P. Wilmot Cancer Center at the University of Rochester Medical Center and lead author of the study. “Much of the reduction in dose and overall reduced relative dose intensity compared to the reference standard was either planned or already seen during the first chemotherapy cycle. We need to find better ways to identify patients at risk in order to provide optimal supportive care.”
The researchers note that these results are particularly alarming in the face of multiple, prior studies which underscore the importance of maintaining full chemotherapy dose-intensity, especially in responsive and potentially curable malignancies like early stage breast cancer. Specific treatment regimen and schedule, age and obesity were also associated with an increased risk of treatment delays and dose reductions.
Although white blood cell boosters, known as colony-stimulating factors, are available to manage neutropenia, the study found that approximately only one-fourth of the patients received colony-stimulating factors during chemotherapy. In addition, most support was reactive or therapeutic, rather than preventative or prophylactic.
Elderly Patients at Greatest Risk
According to the study, an unusually large number of patients age 65 and older were found to be significantly less likely to receive the recommended dose of chemotherapy, even though studies have shown that elderly patients can benefit from chemotherapy as much as younger patients. In fact, approximately two-thirds of older patients received less than 85 percent of the recommended chemotherapy dose.
“Fortunately, today doctors have medicines which they did not have years ago to help avoid some of the serious side-effects of chemotherapy that can lead to dose delays and reductions,” Lyman said.
The women included in the analysis ranged in age from 11 to 90, and had a mean age of 52. Seventeen percent of the patients were 65 years or older, and 49 percent of the total patient population was reported to be post-menopausal. The scope and size of this database is consistent with the demographics and clinical characteristics of women with early stage breast cancer in the general population.
Breast cancer is the most common form of cancer among women in the United States, with more than 200,000 new cases and 40,000 deaths annually.
About the ANC Study Group
The Awareness of Neutropenia in Chemotherapy (ANC) Study Group was formed in September 2000 to develop more accurate prediction models for neutropenia, one of the most serious side effects of chemotherapy. Directed by three leading U.S. hematologists and oncologists including Gary Lyman, M.D., M.P.H., David Dale, M.D., and Jeffrey Crawford, M.D., the group focuses on neutropenia awareness, treatment effectiveness and long-term survival. The group also studies the cost and quality-of-life (QOL) impacts of chemotherapy-induced neutropenia. The ANC Study Group receives grant support from Amgen.
Awareness of Neutropenia in Chemotherapy Study Group
CONTACT: Ann Benner, +1-415-643-1101 (office), +1-415-307-9943 (mobile)