Prolonged impact of chemotherapy on fatigue in breast cancer survivors: a longitudinal comparison with radiotherapy-treated breast cancer survivors and noncancer controls.

BACKGROUND

In this study, the authors examined the influence of prior treatment on the course of fatigue in breast cancer survivors. Patients who received chemotherapy were expected to have greater fatigue than patients who received radiotherapy and noncancer controls 6 months after the completion of treatment, but they were expected to recover to levels similar to those of the other 2 groups 3 years later.

METHODS

Patients with stage 0 through II breast cancer completed the Fatigue Symptom Inventory (FSI) and the Profile of Mood States Fatigue Scale (POMS-FAT) 6 months (T1) and 42 months (T2) after completing chemotherapy with or without radiotherapy (the CT group; n = 103) or radiotherapy only (the RT group; n = 102). An age-matched group of women with no history of cancer (the NC group; n = 193) was assessed over a similar interval.

RESULTS

A significant (P = .041) group × time effect for FSI severity scores revealed that fatigue worsened over time in the CT group but remained stable and lower in the RT and NC groups. There also were significant group effects for FSI days (P < .001) and POMS-FAT (P = .010) scores, indicating that fatigue was significantly greater across time in the CT group than in the NC group (POMS-FAT) or the RT and NC groups (FSI days).

CONCLUSIONS

Contrary to expectations, fatigue did not diminish over time in patients with breast cancer who received chemotherapy. This finding has important implications for patient education and for fatigue monitoring during follow-up. The authors concluded that future research should seek to examine possible mechanisms to explain the apparent prolonged impact of chemotherapy on fatigue in breast cancer survivors.