Of most cancers the cause is unknown. Different factors, age, environmental and genetic (familiar risk) are mixed together and result in one out of four citizens in the Western world and one out of eight in most other countries to be diagnosed during life with cancer. In the developing world, this incidence is rising, due to industrialization, pollution, and adaptation to Western lifestyle, including smoking and diet changes, but also because they get older and other death causes like infectious diseases get better treated.
The Biggest Risk Factor
Overall, aging is the most important risk factor for developing cancer. This is simple mathematics, during life cells need to be replaced and every time this takes place, a risk arises that in this replication a mistake is made. These mistakes, called mutations, accumulate over time, making the development of cancer (after a certain number of mutations) an increasing risk with getting older.
Some are born with mutations already present (occurred while forming the embryo with the genetic material DNA inherited already mutated or damaged DNA while still in the uterus, by medication or smoking of the mother, e.g.), resulting in cancer during childhood (leukaemia, lymphoma, brain or kidney cancers) or in young adults. Most common cancers in the young are lymphoma, bowel and breast cancers (see family risk).
Some agents like smoking (mouth, throat, lung, bladder, cervix), drinking (throat, esophagus, liver), virus infections (HPV, HIV, EBV, hepatitis) or radiation (skin, leukemia, thyroid, breast), provoke several different mutations and are directly related to cancer risk. However, the same cancers can also occur in people, who didn’t have intense contact with these agents. The genetic profile and their response on the treatment of these cancers are often different.
Viruses like HPV ( human papilloma virus, 80% of adults are infected, now vaccine available for young adults before getting sexually active), hepatitis and HIV/AIDS are related to higher cancer risk.
Obesity can increase the risk of relapse and side effects of treatment. Sunburn, especially at a young age increases the risk of skin cancer. Diet also plays a role in cancer risk per region of the world and is important during and after treatment (see information on Food). Cultural differences in food, chemic agents, air pollution, smoking habits, virus risk, bodyweight, and genetic predisposition make cancer risk differ significantly country per country.
Other cancers are seen frequently in family generations. When more than 3 family members of the same bloodline or one under 45 years of age has been diagnosed with cancer of the colon and/or uterus or ovarian and/or breast, there is an indication for a family risk estimation by a genetic consultant, which can guide you in how to prepare you for future risk. (see talk to an expert).
For greater insight into interacting with those suffering from the issues mentioned in the article or if you would like to chat with others affected, I highly recommend joining the app, Reachout.
Elizabeth Charlotte Moser (1973) is a radiation oncologist, healthcare director, advisor and a teacher in Cancer research & treatment. Her work has been focused on modern and targeted therapies, survivorship issues and costs efficiency of cancer care.