By Sally Pattison BAppSc, Adv. Dip. Nat, Adv. Dip. Nut
What is Cancer?
Definition of Cancer from Cancer council:
“Cancer is a disease of the body's cells. Normally cells grow and multiply in a controlled way, however, if something causes a mistake to occur in the cells' genetic blueprints, this control can be lost. Cancer is the term used to describe collections of these cells, growing and potentially spreading within the body. As cancerous cells can arise from almost any type of tissue cell, cancer actually refers to about 100 different diseases.
Cancer cells that do not spread beyond the immediate area in which they arise are said to be benign ie. they are not dangerous. If these cells spread into surrounding areas, or to different parts of the body, they are known as malignant - commonly referred to as cancer.”1
Cancer affects a large number of Australians, both directly and indirectly.
How many people are affected by cancer?
The statistics speak for themselves:
- In the early 1900s, one in 20 people developed cancer
- In the 1940s, one in 16 people developed cancer
- In the 1970s, it was one in 10
- Today, it's one in three! (2)
What are the different types of cancer?
There are over 200 types of cancer; far too numerous to include in this introductory article. However, a list of general categories is shown below:
- Carcinoma: Cancer that begins in the skin or in tissues that line or cover internal organs -- skin, lung, colon, pancreatic, ovarian cancers, epithelial, squamous and basal cell carcinomas, melanomas, papillomas, and adenomas
- Sarcoma: Cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue -- bone, soft tissue cancers, osteosarcoma, synovial sarcoma, liposarcoma, angiosarcoma, rhabdosarcoma, and fibrosarcoma
- Leukemia: Cancer that starts in blood-forming tissue such as the bone marrow and causes large numbers of abnormal blood cells to be produced and enter the blood -- leukemia, lymphoblastic leukemias (ALL and CLL), myelogenous leukemias (AML and CML), T-cell leukemia, and hairy-cell leukemia
- Lymphoma and myeloma: Cancers that begin in the cells of the immune system -- lymphoma, T-cell lymphomas, B-cell lymphomas, Hodgkin lymphomas, non-Hodgkin lymphoma, and lymphoproliferative lymphomas
- Central nervous system cancers: Cancers that begin in the tissues of the brain and spinal cord -- brain and spinal cord tumors, gliomas, meningiomas, pituitary adenomas, vestibular schwannomas, primary CNS lymphomas, and primitive neuroectodermal tumors (3)
How is cancer staging determined?
There are a number of different staging methods used for cancers and the specific staging criteria varies among cancer types. The common elements considered in most staging systems are as follows:
- Site of the primary tumour
- Tumour size and number of tumours
- Lymph node involvement (spread of cancer into lymph nodes)
- Cell type and tumour grade* (how closely the cancer cells resemble normal tissue cells)
- The presence or absence of metastasis (secondary spread to other organs)
The Roman numeral or stage grouping method is used by some clinicians and researchers on almost all cancer types.
The Roman numeral or stage grouping method is described as follows (4)
Stage 0 - Carcinoma in situ.
Stage I, Stage II, and Stage III - Higher numbers indicate more extensive disease: Larger tumour size and/or spread of the cancer beyond the organ in which it first developed to nearby lymph nodes and/or organs adjacent to the location of the primary tumour
Stage IV - The cancer has spread to another organ(s).
Signs and Symptoms
As there are many types of cancer and organs that can be effected it is difficult to list all symptoms to look out for. Some cancers are silent – as in they do not produce symptoms.
Common symptoms include:
Unexplained weight loss
Change in bowel or bladder function
Wounds that won’t heal
Unusual bleeding or discharge
General symptoms that linger – like a cough