TYPES OF CANCER: From the HISTORY AND CLASSIFICATION OF LIVER CANCER, Cancer has the potential to affect every organ in the body. The cells within the ligament tumours have the ability to invade neighbouring tissues and organs,
thus spreading the disease. It is also possible for cancerous cells to break free from the tumour and enter the bloodstream, in turns spreading the diseases to other organs. This process of spreading is called metastasis. (Jemal, et.al,2011).
When cancers have metastasized and has affected other areas of the body, the disease is still referred to the organ of origination. For instance, if cervical cancers spread to the lungs it is called cervical cancer and not lung cancer.
SYMPTOMS OF CANCER And the types of cancer
Local symptoms may occur due to the mass of tumour or its ulceration. For example, mass effects from lung cancer can cause blockage of the bronchus resulting in a cough or pneumonia, oesophageal cancer can narrowing of the oesophagus making it difficult or painful to swallow. Although local pain commonly occurs in advanced cancer, the initial swelling is often painless.
Types of cancer in women or men occurs due to distant effects of cancer that are not related to direct or metastatic spread. These may include; unintentional weight loss, fever, being excessively tired and changes to the skin.
Specific constellations of systemic symptoms termed paraneoplastic phenomena may occur with some cancers. Examples include the appearance of myasthenia gravis in thymona and dubbing in lung cancer.
Symptoms of metastasis are due to the spread of cancer to other locations in the body. They can include enlarged lymph nodes (which can be felt or sometimes seen under the skin and are typically hard), hepatomegaly (enlarged liver) or splenomegaly (enlarged spleen) which can be felt in the abdomen, pain or fracture of affected bones and neurological symptoms.
Cancers are primarily an environmental disease with 90-95% of cases attributed to environment factors and 5-10% due to genetics (Anand, 2008).
Common environmental factors that contribute to cancer death include tobacco (25-30%), diet and obesity (30-35%), infections (15-20%), radiation (both ionising and non-ionising up to 10%), lack of physical activity and environmental pollutants.