To begin, it is pertinent to cancer in the right
perspective. By way of definition, cancer is a malignant tumor or swelling
composed of abnormal cells capable of undergoing uncontrolled proliferation.
Many mistakenly take the view that any swelling or lump is cancer. However,
this is not the case. Unlike benign swellings, cancer cells generally have a
tendency to invade surrounding tissues and may metastasize (detach and spread)
to distant tissues of the body via the bloodstream or lymphatic system. Cancers
arise when there is a disruption of the normal process of cell division. Body
cells are constantly undergoing cell division, although in a controlled manner
to replace the aging and dead cells. However, a defect or mutation sometimes
occurs during this process. If not promptly repaired by the body, resulting in
the formation of abnormal cells continue to proliferate uncontrollably and
eventually lead to cancer.
No doubt the cancer health burden is enormous. Cancer
is said to kill more people each year than HIV / AIDS, malaria and
tuberculosis. According to the International Agency for Research on Cancer
(IARC), 2030, more than 21 million new cases of cancer were diagnosed with 13
million people die from cancer each year. In addition, the statistics showed
that 80,000 Nigerian women die from various forms of cancer each year from
breast cancer at the top of the list.
A complex interaction of several risk factors, some of
which are discussed below determines who comes down with cancer and who does
not:
Smoking
Smoking, asset or liability is involved in most lung
cancers, including nasopharyngeal, esophageal and prostate cancers to mention a
few. In fact, research has shown that nearly 33% of all annual cancer deaths in
the United States results from smoking. Approximately 98% of patients with
small cell lung cancer (SCLC) have a significant smoking history and fortunately,
smoking cessation was associated with improved survival in these patients.
Obesity
Compared with normal weight and body mass index (BMI),
obese people are more at risk of certain types of cancer, including cancers of
the pancreas, colon, kidney, esophagus, breast and endometrial cancer, among
others. One explanation that has been proposed for this increased risk is that
adipose tissue produces excessive amounts of estrogen in obese people. High
estrogen levels have been associated with an increased risk of breast cancer
and endometrial cancer. In addition, obese individuals are more likely to have
high blood levels of insulin and insulin-like growth factor 1 (IGF-1), which
favor the development of certain cancers. Studies have shown that people who
are overweight and obese are at increased risk of 200 to 400% of endometrial
cancer than their counterparts with normal BMI.
HIV / AIDS
Immunocompromised individuals, such as people living
with HIV / AIDS are at higher risk of developing certain types of cancer. Three
of these cancers namely Kaposi's sarcoma, non-Hodgkin lymphoma, and cervical
cancer are called AIDS-defining. For example, an individual infected with HIV
has several thousand higher risk of manifesting Kaposi sarcoma and the risk 70
times higher of developing non-Hodgkin's lymphoma. Some types of cancer other
than they are at risk for anal cancer include Hodgkin lymphoma and lung cancer.
Because HIV / AIDS weakens the immune system is thought to predispose to other
infections that can cause cancer such as human papillomavirus (HPV) has been
implicated in cervical cancer.
Excessive alcohol consumption
Studies have shown that excessive alcohol consumption
increases the risk of oral, throat, esophagus, and liver cancer. Therefore, if
you leave excessive alcohol consumption, the risk of these deadly cancers will
be much less.
Excessive sun exposure
People who are exposed to intense sunlight inadvertently
increase their risk of skin cancer. Numerous studies have implicated the
ultraviolet (UV) in the pathology of skin cancer, including melanoma. Melanin
is a natural pigment of the skin which provides significant protection against
ultraviolet rays. This is why people with fair skin who have less melanin
pigment in their skin are more likely to experience sunburn and skin cancer.
Positive family history
For most cancers, the people who have one or more
close relatives (especially first-degree relatives) who were diagnosed with
these cancers have a significantly higher risk. These people are said to be
genetically predisposed because they may have inherited some of the abnormal
genes. For example, a family history of breast cancer in a first-degree relative
is one of the major risk factors for this type of cancer. If a mother or sister
is affected by breast cancer, the lifetime risk of developing the disease is
increased by four folds.
Increasing age
As people get older, their risk of most cancers also
tends to increase. For example, while breast cancer is rare in women under 25,
the incidence reached a plateau in women aged 50 to 55 years. In addition,
prostate cancer is a disease condition that is usually seen in the elderly
(age> 65 years) and the prevalence may be as high as 80% at 80 years.
