Anatomic Structure System or Substance
Diagnostic Therapeutic and Research Equipment
Diagnostic or Prognostic Factor
Diseases Disorders and Findings
|Drugs and Chemicals|
Experimental Organism Anatomical Concepts
Experimental Organism Diagnoses
NCI Administrative Concepts
Properties or Attributes
Cancer (a.k.a. malignant neoplasm) is an umbrella term for a class of diseases in which a group of cells grows in an uncontrolled fashion beyond its natural limits, invades and destroys adjacent tissues, and may spread to other body parts via the blood stream. Although the risk of cancer is proportionate to a person’s age (i.e. the older the person, the higher the risk), it can afflict people of all ages. According to a recent study, cancer is the fourth most common cause of human death amounting to 12 percent of all death cases per year.
Most cancer types are named after the cells or organs in which they typically begin. For instance, basal cell carcinoma is a cancer that starts in the skin’s basal cells. Modern medicine differentiates between several hundred types of cancer, the most widespread being lung cancer, breast cancer, colon and rectal cancer, prostrate cancer, and skin cancer. Slightly less common, but in no way less dangerous, are kidney cancer, thyroid cancer, bladder cancer, endometrial cancer (neoplasm that forms in the tissue lining of the uterus), and leukemia which is a cancer of the blood-forming organs, such as the bone marrow. The nonmelanoma skin cancer is another common type.
Most medical professionals agree that tobacco smoking, exposure to radiation, certain chemicals or infectious agents, as well as errors in DNA replication, are highly carcinogenic and cancer-promoting factors. However, the exact cause of each particular type of cancer is still subject to dispute and discussion among the competent authorities.
There is a difference between benign and malignant tumors. The benign form of tumor is not cancerous, and affected cells may be removed by surgical intervention. Benign tumors do not spread to other body tissues and organs. In malign tumors, affected cells invade nearby areas, spreading to other parts of the body. Some cancers, such as the leukemia, don’t form tumors.
Cancer types may be grouped in five main categories: carcoma, carcinoma, leukemia, central nervous system cancers, and lymphoma and myeloma. Sarcoma is a type of cancer that begins in the blood vessels, muscle tissues, cartilages, bones, fat, and other supportive or connective tissues. Carcinoma begins in the skin’s cells and in tissues that cover and line various internal organs. Leukemia begins in the bone marrow and other blood-forming tissues, causing the production of abnormal cells which enter the blood stream. The lymphoma and myeloma cancers affect the immune system cells. The cancers of the central nervous system begin in the spinal cord and the brain tissues.
Regardless of its cause or type, a cancer disease can be treated successfully provided that it is identified in its initial stage, before it has spread beyond control. For this reason, informing yourself about typical cancer symptoms can be of life-saving importance. Here are the most often observed:
Continuous exhaustion, often coupled with anemia, is a characteristic condition for many types of cancer, especially those that affect the bowels. Fortunately, it may also indicate a non-malignant (that is, completely treatable) formation or some seasonal virus infection.
Unintentional weight loss
Although the sudden loss of weight may seem a pleasant surprise, it can be a clear indictor for cancer or some other serious disease. If you have recently lost 10 or more pounds without an obvious reason, you are well-advised to consult your physician.
Pain is a vague symptom of many mild to severe conditions. It is more often than not, an indicator of an injury or other non-terminal illness. Yet, it is important to know that lower back pain may signify ovarian cancer or colon cancer while shoulder pain can be a symptom of lung cancer. Headaches are commonly associated with brain tumors (both malignant and benign).
A persistent dry cough can be a symptom of lung cancer. The cough may or may not be accompanied by mucus or blood spittle.
Constipation, diarrhea, blood in the stools, or some other change in the bowel habits may be a symptom of colon cancer as well as several other cancer types. If such an abnormality is accompanied by other cancer symptoms, it is a good idea to schedule a meeting with your doctor.