Cancer is an umbrella term for a collection of diseases which are characterised by abnormal cell growth. This abnormal cell growth can spread to different regions throughout the body and cause cellular dysfunction which may interrupt vital biological functions. However, not all abnormal cell growths are invasive/cancerous, tumors may form which are benign and offer minimal risk of spreading to other regions of the body.
Within the human body our cells are constantly growing, dying and being replaced by new cells. This is an extremely important process which allows us to maintain roughly 100, 000 billion cells (approximate average cell count for a fully grown adult), which each have specific functions and that are required to work in unison to maintain a healthy human body.
In order to maintain this continuous cycle of cell replacement, two cell types known as oncogenes and tumor suppressor genes play a very important role in regulating this process. Oncogenes role within the cycle is to find cells that are ‘programmed’ to die via a process known as apoptosis and instead cause the cell to survive and multiply. On the other hand, it is tumor suppressor genes role to find cells with damaged DNA and prevent the dysfunctional cell from proliferating and passing their dysfunction onto future cells.
Typically, cancerous/malignant tumors are formed when there is an interruption to this cycle. Cellular dysfunction in either the oncogenes or tumor suppressor genes allows for the replication of damaged cells to occur and leads to a disruption in the healthy cell reproduction cycle. Cancer cell growth is commonly caused by excessive activity of oncogenes and/or by reduced activity of tumor suppressor genes which results in the proliferation of damaged cells and therefore leads to malignant tumor growth. Although, it should be recognised that there are many steps which must occur in order for the cell reproduction cycle to be compromised and certain environmental and personal factors may cause or accelerate these processes.
Currently it is recognised that more than 30% of cancer-related deaths are avoidable by limiting individuals’ exposure to modifiable risk factors associated with cancer. However, not all risk factors are modifiable and certain individuals are placed at an increased risk due to their personal circumstances. The following is a list of both modifiable and non-modifiable risk factors:
Modifiable Risk Factors
- Being overweight / obese
- Physical inactivity
- Poor diet & excessive alcohol consumption
- Air pollution
- Unsafe sex (sexually transmitted infections)
- Excessive sun exposure
- Radiation exposure
- Exposure to carcinogenic material
Non-Modifiable Risk Factors
In Australia, approximately 128,000 new cases of cancer will be diagnosed in 2014, with this figure increasing to 150,000 by 2020. On average, 1 in 2 Australian men and 1 in 3 Australian women will be diagnosed with cancer before the age of 85. Currently, cancer is one of the leading cause of death in Australia, with lung cancer alone accounting for 5.5% of all deaths in 2012. Other prevalent forms of cancer also include: prostate, colorectal, breast and melanoma (skin).
Signs, Symptoms and Detection
As there are more than 100 forms of cancer, signs and symptoms may vary significantly between each condition. Furthermore, some of the signs and symptoms of cancer are shared with other diseases and can be very hard to diagnose. Some of the more common potential signs and symptoms of cancer include:
- Abnormal bleeding
- Unexplained weight loss
- Formation of a new lump
- Altered bowel movements
- Presence of an abnormal mole
Please note that this list does not cover all potential signs and symptoms, however, you should seek professional medical advice if any of these signs and symptoms apply to you, or if you are concerned that you may be at an increased risk of developing cancer.
Prevention and Management
A large portion of cancer related deaths are avoidable. To reduce the likelihood of developing cancer, the amount of modifiable risk factors should be limited where possible. Additionally, to improve prevention the focus should be placed on adopting a healthy diet and lifestyle.
- Perform regular physical activity. Healthy individuals should be aiming to achieve a minimum of 150 minutes of moderate intensity physical activity per week. With physical activity being performed 5-7days each week. Additionally, it is also recommended that individuals participate in strengthening activities at least 2 days per week. If you would like more information regarding the amount and type of physical activity you should be performing, please consult your doctor or an exercise physiologist.
- Avoid/cease smoking. Smoking has been identified as one of the largest risk factors associated with the development of cancer (especially lung cancer). Abstinence from tobacco is one of the most beneficial changes you can make for your health.
- Maintain a healthy diet. Currently there is no conclusive evidence to suggest there is an optimal diet for cancer prevention. However, it is recommended that individuals achieve a minimum of two serves of fruit and five serves of vegetables each day, as well as limiting the amount of red and processed meats consumed. If you would like more information regarding healthy dietary habits, please consult your doctor or a qualified dietician.
- Avoid excessive alcohol intake. Alcohol consumption of more than two standard drinks per day has been linked with an increased risk of developing a number of different forms of cancer.
- Avoid excessive sun exposure. It is recommended that Australians achieve 5-15minutes of sun exposure 4-6times per week in order to maintain appropriate vitamin D levels. Exposure greater than these recommendations may lead to a significantly increased risk of developing skin cancers. Furthermore, individuals should avoid direct sunlight between 10am-2pm due to dangerous levels of ultraviolet light exposure and always ensure they are adequately protected from the direct sunlight (e.g. sunscreen, hat, shirt etc.).
- Attending regular cancer screenings. Currently there a numerous screening tests that can be performed to determine the presence of various types cancers. It is important that as we age we take the time to perform regular check-ups to ensure cancer progression is kept to a minimum. Additionally, early detection of cancer can play a significant role in cancer treatment and may greatly increase survival rates in individuals diagnosed with the condition. Within Australia, free screening for breast, cervical and bowel cancers is available. Please consult your doctor today to determine which cancer screening tests you may be eligible for.
**CLICK HERE to view the Exercise and Sports Science Australia Position Statement on Optimising Cancer Outcomes Through Exercise