Cancer is a group of diseases in which abnormal cells proliferate uncontrollably and spread to other parts of the body. The word cancer is not one single disease, but a category of more than 100 different conditions. Cancers can affect any tissue in the body and may take on many forms in different areas. Most cancers are named after the type of cell or organ in which they first appear. In addition, cancers tend to have the same name as the primary tumor, or a site in the body where they originated.
Tumors can develop anywhere in the human body, but there are some general characteristics that define all types of cancer. Tumors are marked by uncontrollable cell division and the potential to metastasize. Children do not usually develop cancer, with the exception of leukemia. Risk factors for cancer include age and genetic predisposition, although environmental factors are known to play a role in some cases. For example, smoking can lead to the development of certain types of cancer.
Symptoms of cancer may not be noticeable until it has reached an advanced stage. It may take some time to manifest symptoms, as the body adapts to the damaged tissue. However, once the cancer has spread to other parts of the body, the symptoms may be minimal or even disappear altogether. Cancer patients often experience fever, weakness, and pain in a stretched organ. In addition to the physical symptoms, cancer patients often suffer from infections, which can lead to death.
Although cancer is not hereditary, genetic predisposition is passed down to offspring. Mutations in a particular gene cause the cells to become unstable, leading to cancer. The mutations are caused by a single or multiple types of defective genes. These genes are called oncogenes and they can cause cancer in many different types of cells. These genes are typically found in the DNA of cells. When this happens, the cell begins to produce abnormal cells, which is why they are characterized as cancer.
Even though early modern medical practitioners attempted to define cancer, they did so by defining the disease’s most common locations and symptoms. These approaches exemplified their theories of moral causation and causality. Nonetheless, many early modern medical practitioners were unsure of what cancer actually was. The problem, however, was that many of these theories were based on inaccurate interpretations of the disease. Because of this, cancer remains elusive.
The definition of cancer varies by type of cancer. Adenocarcinomas are characterized by the spread of tumors beyond their original tissues. Cancer cells that reach the infiltration point can release a substance that breaks down the cellular membranes. This process is called metastasis. As cancer metastasizes to distant sites, the likelihood of it spreading to other organs increases dramatically. These diseases are generally more fatal than most other types of cancer.
Carcinogenesis is a biological process that involves sequential mutations in the genes of the body. These mutations cause abnormal cell growth and ultimately lead to the development of malignant cancers. Research is underway to better understand how carcinogenesis works, and to create specific drugs for the disease. One such treatment is gene-replacement therapy. This treatment may ultimately lead to a cure for cancer. The disease has many implications and a cancer diagnosis can make the difference between life and death.
