NEW YORK (Reuters Health) - Women with breast cancer who developed anemia during chemotherapy had nearly three times the risk of local recurrence as those who did not develop anemia, according to a study published this week.
“We speculate that there may be an interaction between chemotherapy/radiotherapy and anemia,” study chief Dr. Peter Dubsky, from the Medical University of Vienna, Austria, said in a statement.
“Both treatment modalities have been shown to be less effective in anemia patients. Since we do not see the effect in terms of relapse-free survival, the interaction with local adjuvant treatment may play a more important role,” Dubsky added.
The results are based on a study of 424 premenopausal women with early-stage disease who were treated with cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) after surgery, as part of the Austrian Breast and Colorectal Cancer Study Group Trial 5. All of the women who had breast-conserving surgery received radiation, whereas radiation was optional in women who had radical mastectomy.
The findings, appearing in the April 1st issue of the journal Clinical Cancer Research, indicate that 19.6 percent of women who developed anemia experienced a relapse during 5 years of follow-up compared with just 8.9 percent of women without anemia. This translates into nearly a three-fold increased risk of relapse in anemic patients.
Women without anemia experienced a significantly longer local relapse-free survival than women with anemia, according to the study.
Overall relapse-free survival, however, was not significantly affected by anemia status. “The effect was limited to local recurrences. Any explanation of the limit is pure speculation,” Dubsky said.
No difference in overall survival was noted either, although Dubsky believes this may simply be a function of relatively small patient numbers and length of follow-up.
SOURCE: Clinical Cancer Research, April 1, 2008.