September 10, 2007
American Cancer Society

Chemotherapy May Be Culprit for Fatigue in Breast Cancer Survivors

A new study finds that, compared to healthy women, breast cancer survivors reported more days of fatigue and more severe fatigue symptoms. The study, published in the October 15, 2007 issue of CANCER, a peer-reviewed journal of the American Cancer Society, found women who received both chemotherapy and radiotherapy reported the most severe and prolonged fatigue.

Fatigue is a common complaint in the general population and, anecdotally, common among cancer patients. Comparative fatigue studies between the two populations, however, have been marred by methodological shortcomings, such as poorly matched controls and patient populations. The studies do not consistently agree whether or not fatigue is a more common complaint among cancer patients compared to the general population.

Dr. Paul Jacobsen from the Moffitt Cancer Center in Tampa, Florida and co-investigators followed 221 women with non-metastatic (early stage) breast cancer treated with either radiography (n=121) or a combination of chemotherapy and radiography (n=100) and 221 age- and geographically-matched healthy women (i.e., controls) at two, four, and six months after treatment.

The authors expected to find the greatest difference in fatigue scores just after treatment, diminishing with time. Surprisingly though, they found that breast cancer patients had a significantly greater number of days with reported fatigue at each of the four assessments, and that even at the six-month follow-up assessment, a statistically significant and clinically meaningful group difference in fatigue duration was still evident. They studied further and found that the difference was attributable primarily to heightened fatigue in those women who received both chemotherapy and radiotherapy.

These findings provide strong evidence that women with non-metastatic breast cancer treated with adjuvant chemotherapy are at significantly greater risk for severe fatigue. The next step, explains Dr. Jacobsen, is to "explore whether interventions administered during or at the end of treatment are effective in preventing or limiting fatigue in the post-treatment period." They point in particular to the role of exercise, which has been shown to reduce fatigue in breast cancer survivors.