The incidence of cancer diagnosis in Australia is on the rise – with prostate, bowel, breast, melanoma and lung cancers accounting for over half of all newly diagnosed cases. Improvements in treatment modalities and early detection has seen a significant shift in the likelihood of surviving a cancer diagnosis.
In men, prostate cancer (PCa) remains the most commonly diagnosed cancer worldwide. While prognoses are generally good if caught early, the different forms of cancer therapies available are usually accompanied by considerable and often debilitating adverse effects.
Androgen deprivation therapy (ADT), a form of anti-hormone therapy aimed at reducing the concentration and/or physiological effect of circulating androgens (i.e. testosterone), has become a key component in the treatment of metastatic PCa – significantly increasing survivability and disease-related morbidity.
However, ADT induces severe hypogonadism and is associated with numerous adverse effects that negatively impact a patient’s health and quality of life. Perhaps the most prominent side effect is a change in body composition, increasing fat mass and reducing muscle mass and strength. ADT also increases the rate of bone mineral loss and fracture risk. Research has shown deleterious effects on insulin sensitivity, with population-based epidemiological studies suggesting a greater likelihood of developing type-2 diabetes and cardiovascular disease. Further adverse effects include sexual dysfunction, mood swings, depression, anxiety, a general feeling of fatigue and an overall reduced quality of life.
Exercise therapy is often proposed as a potential strategy to ameliorate the adverse effects of ADT. Indeed, there is considerable evidence underpinning the health benefits of regular physical activity. In healthy older adults, exercise increases lean body mass, reduce body fat, improve insulin sensitivity and improve general well-being and quality of life. Studies in men undergoing ADT have demonstrated that appropriately prescribed exercise can assist in maintaining bone mineral density, reducing the risk of falls and fracture, improving muscle mass and insulin sensitivity.
Moreover, exercise during ADT is associated with reduced perceptions of fatigue and a significant improvement in patient reported quality of life.
While there is sufficient evidence advocating the use of exercise during ADT, only a minority of patients receive a specific referral for an exercise specialist. In Australia, PCa and ADT patients are able to access the services of Accredited Exercise Physiologists (AEPs) through public and private health pathways. However, the uptake of such services are low – likely due to a lack of awareness within the urological/oncological sectors or financial difficulties of the patient.