(ChemotherapyAdvisor) – Women overweight or obese when diagnosed with breast cancer are at higher risk of cancer recurrence or death than those who are leaner, despite receiving chemotherapy dosed according to actual body weight, a study presented during the 8th European Breast Cancer Conference in Vienna, Austria, March 23 concluded.
The Cancer and Leukemia Group B/Intergroup 9741 study enrolled 2,005 women between 1997 and 1999; median follow-up was 11 years. Baseline height and weight were available for 1,909 patients. Mean baseline body mass index (BMI) was 28.5kg/m2; 1.2% of patients were underweight (BMI <18.5kg/m2), 32.6% normal weight (18.5–24.9kg/m2), 32.9% overweight (BMI 25–29.9kg/m2), and 33.3% obese (BMI ≥30kg/m2).
“All patients received doxorubicin, cyclophosphamide, and paclitaxel based on body surface area without a cap or adjustment,” noted Jennifer Ligibel, MD, Dana-Farber Cancer Institute and Harvard Medical School, Boston, and colleagues. Overall, 49% of patients were premenopausal, 65% had estrogen receptor positive cancers, and 70% received tamoxifen.
“We found a modest linear relationship between BMI and outcome in node-positive breast cancer patients receiving chemotherapy,” the investigators stated. In adjusted analyses, BMI was significantly related to both relapse-free survival (P=0.010) and overall survival (P=0.022). The ten-year relapse-free survival of a patient with a BMI of <25kg/m2 vs. one with a BMI of 35kg/m2 was 71.4% vs. 65% and ten-year overall survival, 76.9% vs. 69.8%.
“Additional research is needed to determine the impact of weight loss on breast cancer outcomes,” they concluded.
Abstract (Enter “Ligibel” in the author box to search for Abstract No. 413)