The disease of cancer is divided into many forms, guiding treatment and aiding understanding among patients. All forms of cancer involve aberrant cell mutations, but the results of those mutations can occur in a variety of locations and tissues and differ in their aggressiveness and tendency to migrate through the body. Here is more about cancer types and how they are classified.
Tissue Type and Strain
Cancer is commonly referred to by the part of body where it occurs, such as with brain cancer, skin cancer and lung cancer. Clinically, however, cancer is classified by the type of tissue it affects. The five types are:
Within these categories, cancers are often grouped into strains. Small-cell and non-small cell lung cancers are examples of strains of lung carcinomas.
Heritable and Lifestyle Related
Although research has not fully determined what percentage of cancer risk involves heredity and what percentage depends on lifestyle risk factors, some cancers are believed to rely more heavily on one versus the other. For example, lung cancer risk is clearly elevated by smoking and radon gas exposure. Heredity appears to be most significant as a risk factor when family members have had multiple cases of rare cancers at young ages.
Grouping by Development
Cancer can also be categorized by its level of development. In Stage 1 cancers, cancer is just beginning to develop in one area and has not traveled to lymph nodes or nearby organs. As cancer progresses through stages 2 and 3, it reaches lymph nodes and organs nearby and farther away depending on the type of cancer involved. When cancer reaches stage 4, it has spread to organs or tissues distant from its origin. This last stage is when cancer is most likely to be classified as terminal, which means that death is considered inevitable.
Depending on the type and stage, cancer may be treated with surgery, radiation, chemotherapy or a combination of approaches. As research on cancer types continues, more forms may be discovered along with new treatments to address them effectively.