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Study Helps Define Cancer-Related Fatigue

CancerWise - August 2008

In an effort to better define and ultimately address cancer-related fatigue more effectively, a qualitative study has identified several primary themes among patients being treated with standard radiation therapy.

Significance of results

Fatigue is the most distressing and common symptom related to cancer and cancer treatment according to patients, says Loretta Williams, Ph.D., a nurse and instructor in M. D. Anderson's Department of Symptom Research.

“Information from this study will make us be better equipped to ask the right questions of patients to assess fatigue,” says Williams, who presented the results in May at the 33rd Annual Congress of the Oncology Nursing Society. “Health care professionals, including nurses, will be in a much better position to intervene with patients to manage or prevent fatigue.”

Research methods

The study included open-ended, audio-taped interviews with 21 patients, all of whom were receiving radiation therapy at M. D. Anderson. The patients were evenly divided with diagnoses of breast, prostate, and head and neck cancer.

Of the 21 patients who were interviewed during the fifth week of radiation therapy, 57% were women, and the average patient was 54 years old.

Primary results

Based on patient interviews, researchers identified three major aspects of cancer-related fatigue.

Patients reported:

An overall loss of strength or energy — This condition included feelings of tiredness or weakness, which could progress to exhaustion, and lack of energy and stamina.

Patients’ comments included: “I don't have a body part that’s tired. My whole body is tired;” “I just have a weak feeling ... pretty well all over;” and “Fatigue to me is just a feeling of no energy.”

More than 85% of the patients in the study described fatigue as a “tiredness” and having a “lack of energy.”

The development of specific physical and mental sensations — Patients described physical symptoms of fatigue as “aching, feelings of heaviness or weight, slowness of movement, lack of appetite, and mental sensations of psychological distress and difficulty thinking or concentrating,” according to the study.

A loss of desire to participate in usual activities — Study participants said fatigue caused a lack of motivation or inability to perform usual activities and a decreased interest in social activities.

Many patients frequently reported that they didn't want to be around others because it was too draining to be cordial or to keep up a conversation.

According to the researchers, the terms mentioned in the study would be good for patients to use when speaking with health care providers about fatigue.


“While fatigue is a well-recognized symptom of cancer and its treatment, the measurement of fatigue has been based on many different ideas and definitions,” Williams says. “Few of these definitions have included patient input. We're trying to define fatigue based on patient experience.”

What’s next?

Williams and her team have similar, ongoing studies to better define fatigue among patients receiving chemotherapy and new targeted therapies. Their ultimate goal is to develop a single definition of cancer-related fatigue.

— Adapted by Darcy De Leon from an M. D. Anderson news release

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© 2015 The University of Texas MD Anderson Cancer Center