Exercise as it relates to Disease/The effects of Physical Activity on Brain Cancer Survivors

Physical exercise has consistently been identified as a central element of rehabilitation for many chronic diseases including several types of cancer. The main benefit of exercise when applied to brain cancer survivors is to improve quality of life, cognitive function and improved mental health.

Background
There are more than 40 major types of brain tumours, which are grouped into two main types: benign and malignant.

Benign: A benign tumor is a mass of cells (tumor) that lacks the ability to invade neighboring tissue or metastasize. These characteristics are required for a tumor to be defined as cancerous and therefore benign tumors are non-cancerous.

Malignant: A malignant tumor contrasts with a non-cancerous benign tumor in that a malignancy is not self-limited in its growth, is capable of invading into adjacent tissues, and may be capable of spreading to distant tissues. A benign tumor has none of those properties.

All types of brain tumors may produce symptoms that vary depending on the part of the brain involved. These may include headaches, seizures, problem with vision, vomiting, and mental changes. Not all brain tumors are alike, even if they arise from the same type of brain tissue. Tumors are assigned a grade depending on how the cells in the tumor appear microscopically. The grade also provides insight as to the cell's growth rate.

The following grades are:


 * Grade I: The tissue is benign. The cells look nearly like normal brain cells, and they grow slowly.
 * Grade II: The tissue is malignant. The cells look less like normal cells than do the cells in a grade I tumor.
 * Grade III: The malignant tissue has cells that look very different in appearance from normal cells. The abnormal cells are actively growing and have a distinctly abnormal appearance (anaplastic).
 * Grade IV : The malignant tissue has cells that look the most abnormal and tend to grow quickly.

Tests for brain cancer involve a history, physical exam, and usually a CT or MRI brain scan; sometimes a brain tissue biopsy takes place as well. Treatments are usually directed by a team of doctors and are designed for the individual patient; treatments may include surgery, radiotherapy, or chemotherapy, often in combination. Side effects of treatments range from mild to severe, and patients need to discuss plans with their treatment team members to clearly understand potential side effects and their prognosis (outcomes). Depending on the brain cancer type and overall health status of the patient, brain cancer frequently has only a fair to poor prognosis; children have a somewhat better prognosis.

Treatment
There are various approaches to treating cancer, many of which involve combinations of therapies to provide the most effective treatment. Radiotherapy Radiotherapy (also called radiation therapy or x-ray therapy) uses high energy radiation to destroy cancer cells or impede their growth. It is commonly delivered externally, through the skin. However, it can be administered internally (brachytherapy) with the placement of small sources of radioactive material in or near the cancer. Side effects from radiotherapy include include:


 * Fatigue (tiredness)
 * Dry, red or itchy skin
 * Loss of appetite
 * Nausea (feeling sick)
 * Digestive problems
 * Dry or sore throat or mouth
 * Cough or shortness of breath

Chemotherapy Chemotherapy is almost always used in combination with other treatments; it is not curative for most solid cancers when used alone. Many cancers rely on particular hormones to be able to grow. These cancers can often be controlled by drugs that suppress the body's hormone production or block the effect of the hormone on tumor cells. Side effects from chemotherapy include:


 * Nausea and vomiting
 * Diarrhea or constipation (often due to anti-nausea medication)
 * Fatigue (tiredness)
 * Mouth sores or ulcers
 * Increased risk of infection
 * Increased risk of bruising
 * Hair loss
 * Muscle weakness
 * Dry or tired eyes

Surgery is often used in combination with radiotherapy and/or chemotherapy to make sure that any cancer cells remaining in the body are removed.

An estimated 69,720 new cases of primary brain tumors were diagnosed in 2013 and includes both malignant (24,620) and non-malignant (45,100) brain tumors. As many as 75% of cancer survivors have reported experiencing chemotherapy-related cognitive impairment (CRCI) which may negatively affect multiple aspects of cognitive function.

Some side effects of CRCI may include:


 * Cognitive inability,
 * Linguistic difficulty,
 * Decreased reaction times,
 * Impaired memory and concentration,
 * Decreased ability to maintain activities of daily living.

Most unsettling is that CRCI has been reported to persist long after completion of treatment and may affect patients with brain cancer more severely.

The Effects of Physical Activity
Physical activity is widely recognized as a means for the primary prevention of chronic diseases as well as in patients' treatment and rehabilitation. Exercise interventions for brain cancer rehabilitation should be used to help preserve or restore physical and psychological functions that are adversely affected by cancer related therapies. Benefits from exercise based interventions for individuals recovering from brain cancer include improvements in cardiorespiratory fitness, greater peak oxygen consumption, better physical functioning, improved cognitive function and a reduction in the symptoms of fatigue. It is a combination of these characteristics that leads to an increase in quality of life.

Recommendations
When defining the amount of physical activity or exercise, it is important to treat every patient as an individual, hence a specific program must be made for every patient. An important interrelationship exists between the total dose of activity and the intensity at which the activity is performed. Independently, interventions of cognitive and exercise training have resulted in increases in functional capacity and improvements in various measures of cognitive function.

Consideration
Perceived barriers to exercise


 * Age: Average age of LC patients at the time of diagnosis is high (above 60years)
 * Co-morbidities: COPD, arterial hypertension, cardiac disease, peripheral vascular disease, previous tumors and diabetes
 * LC symptoms: Fatigue, dyspnea, anorexia and pain
 * Emotional wellbeing: Depression, anxiety, lowered self-esteem and loss of sense of control

Strategies to improve exercise participation and adherence


 * Exercise programs tailored according to patient’s condition
 * Management of cancer symptoms and treatment complications
 * Psychological and social counseling
 * Educational and motivational sessions
 * Physical activity integrated into cancer treatment plan
 * Encouraging Oncologist to prescribe physical activity