Cancer can be defined as a group of various disease whereby an individual’s cells abnormally mutate and multiply. These abnormal cells then begin to spread into surrounding structures which causes healthy cell function to be impaired and compromised. Left untreated, uncontrolled multiplication of cancerous cells will incur further damage and eventual host death. Breast, bowel, prostate, skin and lung cancer are the most commonly diagnosed cancer cases in 2017 with over 134,000 people estimated to be receive their first diagnosis of cancer by the end of 2017.
Following the detection of cancer, an individual will be diagnosed relative to the presentation and stage of disease progression. The stage which an individual is in will determine the appropriate treatment which is to be undertaken post diagnosis. The stages are:
- Stage 0: often referred to as ‘in stu neoplasm’ meaning there is a group of abnormal cells in an area of the body which may become cancerous in the future. The size of the cells are often too small to be classified as tumors.
- Stage 1: the cancerous cells are contained to the area they were found.
- Stage 2: the cancerous cells are larger than stage 1 typically would present and/or have spread to surrounding tissues.
- Stage 3: the cancerous cells are larger and have spread to the surrounding tissue and/or the lymph nodes.
- Stage 4: the cancerous cells have spread (metastasized) to other areas of the body.
Treatment of Cancer
Treatment of cancer involves the implementation of either one or multiple therapy modalities which include chemotherapy, radiation therapy, hormone deprivation treatment and surgery. These methods are employed to prevent the spread and reduce the multiplication of cancer cells. Despite their importance in the treatment process, such treatment paths can lead to a variety of complications which may impair the functionality of otherwise healthy bodily systems (e.g. cardiovascular, respiratory and musculoskeletal systems). An individual may also experience a loss of sensation (neuropathy), abnormal bowel function, fluid retention (lymphedema), be at an increased risk of metabolic diseases (e.g. diabetes) and osteoporosis (loss of bone mineral density). However, the most common and debilitating side effect of cancer treatment is fatigue, often referred to as cancer related fatigue, and occurs because of hormonal fluctuation.
The Role of Exercise
The role of exercise in cancer treatment is primarily to mitigate the risk posed by the therapies previously listed and optimize patient outcomes. Exercise has been applied to various groups of cancer sufferers who have undergone various treatment methods. Current research finds that exercise before/during/after primary treatment increases cardiovascular, respiratory and musculoskeletal function whilst decreasing metabolic risk factors.
For example, androgen deprivation therapy (ADT) is a common treatment for prostate cancer. This decreases the testosterone in the male subject’s body and in turn leads to a decrease in libido, muscle atrophy, osteoporosis and fatigue. Similarly, an individual’s blood lipids, blood pressure and blood glucose will rise placing them at considerable risk of high cholesterol, hypertension and diabetes. Now without exercise intervention, the male subject will be at higher risk of cardiovascular disease morbidity and mortality because of treatment intended to eradicate his prostate cancer. However, the prescription of a tailored exercise program by an Exercise Physiologist will provide the stimulus required to challenge and improve the individual’s cardiovascular, musculoskeletal system and body composition whilst preventing the onset of cardio-metabolic conditions. This stimulus may include a combination of resistance (increases lean muscle mass and physical function) and aerobic/anaerobic training (increases fitness and cardiovascular efficiency). Additionally, overcoming the challenge of exercise also translates into improved self-confidence and self-image which is important for the maintenance of strong mental health during all stages of cancer related treatment.
Exercise prescription for people influenced will vary depending on the type/stage of cancer, treatment chosen by the primary health care professionals and the preferences/requirements of the individual. Exercise should be viewed as an essential concurrent treatment to the primary care of a cancer patient and be implemented with the intention of increasing function, targeting symptom presentation, slowing the degeneration of bodily function and improving quality of life.