Physical inactivity in childhood cancer survivors

Many adult survivors of childhood leukaemia get little or no exercise, which increases their chances of becoming obese and developing other health problems. Before the mid-1960s, few children survived acute lymphoblastic leukaemia (ALL), the most common childhood cancer, in which the bone marrow produces large numbers of immature, abnormal white blood cells that quickly replace normal cells. But with advances in the medical field in recent times, most children are now cured, and the number of adult survivors is growing. Overcoming paediatric leukaemia may only mark the beginning of a young survivor's lifelong battle to stay healthy, and the lack of any physical activity or exercise can only lead to complications such as obesity, cardiovascular disease and osteoporosis. The problem appears largely related to long-term treatment side effects — in particular, the effects of radiation therapy to the brain. Researchers from the Memorial-Sloan Kettering Cancer Center in New York surveyed 2,648 adult survivors of ALL. Overall, it was found that ALL survivors were 74 per cent more likely to be sedentary than the general population. In addition, they were 44 per cent more likely to fall short of recommended exercise goals for adults, at least 30 minutes of moderate exercise on most days of the week. ALL survivors who had been treated with radiation to the head were particularly likely to be sedentary. This finding suggests that late effects of the treatment, which include growth hormone deficiency and balance and coordination problems, may prevent many survivors from being active. That is, radiation therapy given to the head affects the central nervous system in a way that can interfere with physical activity. However, this obstacle can be overcome through training, which can be started when children are first coming off their cancer therapy, rather than years later. Radiation therapy to the head is no longer used for childhood ALL as regularly as it once was. However, some children with particularly aggressive cases still receive the treatment, as do most children with brain tumours — the second-most common cancer of childhood. But it is believed that some ALL survivors who received chemotherapy alone may be at risk of physical inactivity and would benefit from more exercise.