Data from a new study point to an alarming pattern in breast cancer treatment: more than 50% of women with early-stage breast cancer have not received their full, recommended dose of potentially life-saving chemotherapy.
A comprehensive retrospective analysis showed that 56% of the almost 20,800 women who were being treated for cancer in 1,243 community-based oncology practices in the U.S. received less than 85% of their recommended dose intensity, as prescribed in the optimal treatment plan, because of delays of at least one week (in 25% of patients) or dose reductions (in 37%). Earlier studies have indicated that receiving less than 85% of the recommended dose intensity can result in lower survival rates for patients.
The primary reason for the chemotherapy delays is the presence of neutro-penia, a deficiency of white blood cells, which fight infection and which are destroyed by the effects of the chemotherapy. If the white blood cell count falls too low, patients are at increased risk for infection and, consequently, chemotherapy must be delayed until the cells are replenished.
Although white blood cell “boosters,” known as colony-stimulating factors, are available for the treatment of neutro-penia, only 25% of patients received them during chemotherapy.
The researchers noted that these results are particularly disturbing because earlier studies have underscored the importance of maintaining full chemotherapy dose intensity, especially in responsive and potentially curable malignancies, such as early-stage breast cancer. The study also disclosed a tendency of oncologists to lower dose intensity in order to reduce side effects.
Almost two-thirds of patients older than age 65 were less likely to receive the recommended doses, even though studies have shown that elderly patients can benefit from chemotherapy as much as younger patients. African-American women were also more likely to experience delays in treatment because of lower white blood cell counts.
The women in the study ranged in age from 11 to 90, with a mean age of 52.