Physical exercise : effects in cancer patients

Abstract

Physical exercise plays an important role in cancer prevention as well as in the prevention and treatment of cancer related fatigue during and after treatment. Some of these effects are presented in the thesis of M.J. Velthuis. In Part I effects of physical exercise on anthropometric measurements are examined in the Sex Hormones and Physical Exercise (SHAPE) study, a randomised controlled trial in 189 sedentary healthy postmenopausal women. Results showed that the exercise programme did not affect weight, body mass index or hip circumference. However, the programme did positively influence body composition, i.e. more lean mass instead of fat mass was found in women allocated to the exercise programme. This may be related to a lower risk of breast cancer and other chronic diseases. In Part II effects of physical exercise during cancer treatment are presented. Main outcomes were cancer related fatigue, health care utilisation, sick leave and production losses. A systematic literature review of questionnaires that measure cancer related fatigue showed that the ‘Brief Fatigue Inventory’ scored highest among one-dimensional questionnaires on several psychometric properties and user-friendliness. Among multi-dimensional questionnaires the ‘Fatigue Symptom Inventory’ scored highest. It is recommended to repeat the assessment of psychometric properties, even of these previously validated questionnaires, to ensure that they comply with increasingly stringent quality criteria. Supervised aerobic exercise programmes during breast cancer treatment seem to be a promising and feasible therapy in the management of cancer related fatigue. That was the conclusion of a meta-analysis of the evidence from randomised controlled trials that assessed the effectiveness of exercise during cancer treatment on reducing fatigue. However, scientific evidence for exercise in patients with other cancers than breast cancer was not found. This meta-analysis resulted in the design of a randomised controlled trial to study the effects of physical exercise in patients during treatment of breast or colon cancer. This study is called the Physical Activity during Cancer Treatment (PACT)-study. In the trial (cost)effectiveness of an 18-week supervised group exercise programme will be compared to usual care. The aim is to include 150 breast and 150 colon cancer patients undergoing treatment. The PACT study, coordinated by the Comprehensive Cancer Centre Middle Netherlands (IKMN) and the University Medical Center Utrecht, is financed by the Netherlands Organisation for Health Research and Development (ZonMw) and the Dutch Cancer Society (KWF Kankerbestrijding). The study started in 2010 and results are expected in 2013. Part III includes two studies on effects of physical exercise as a part of rehabilitation after cancer treatment. The reliable and valid assessment of the level of fear of movement prior to cancer rehabilitation may be helpful. To assess fear of movement in cancer survivors the 11-item 2-factor model of the Modified Tampa Scale for Kinesiophobia-Fatigue (TSK-F) showed the best fitting model. Regular physical exercise programmes may be effective in patients without fear of movement, while programmes with a specific focus on reducing fear of movement may be offered to cancer survivors with increased levels of fear.