MedWire News: A significant minority of breast cancer patients experience persistent fatigue up to 5 years after completion of their treatment, a review of the evidence has revealed.
"This is not a phenomenon that occurs solely during treatment, and given the increasing number of breast cancer survivors it is something not to be dismissed lightly," study authors Oliver Minton and Patrick Stone from the St. George's University of London in the UK comment.
Treatment for breast cancer carries a number of other side-effects including nausea, vomiting, anorexia, and alopecia.
Most of these acute side-effects do not persist after the end of treatment and women are generally willing to tolerate them in order to maximize their chances of a successful outcome.
In the current study, the authors posed the question: "Is fatigue simply another acute side-effect of treatment? Or might it persist for months or years after the completion of therapy?"
To investigate, they performed a systematic review of the literature for studies that assessed fatigue in breast cancer survivors. They identified 18 such studies with follow-up periods of between 4 months and 10 years.
All studies included a multi-item fatigue measure, including both mental and physical domains, and had to involve a within-patient comparison (before and after treatment) or a between-group comparison (patients versus controls).
Fourteen studies demonstrated the presence of continued fatigue and/or differences in fatigue levels compared with a healthy reference population up to 5 years after treatment; the prevalence ranged from 5 to 34% with a mean figure of approximately 20%.
One short-term study reported no increase in fatigue at 4 months. Three studies (with an average follow-up period of longer than 5 years) did not identify overall quality of life differences in breast cancer survivors when compared with a reference population.
"The data strongly suggests that in affected women any improvement is seen only after 2 years and that fatigue may continue up to 5 years following treatment," Minton and Stone conclude in the journal Breast Cancer Research and Treatment.
Free abstract
