Carcinoma

Carcinoma, cancer that develops in the inner and outer surfaces of the body, such as the skin, the lining of the gastrointestinal tract, the inside of blood vessels, and the lungs. Like all cancers, carcinomas are malignant tumors in which cells grow uncontrollably, eventually crowding out normal cells. Also, like other cancers, carcinomas often spread to other areas of the body or metastasize via the blood or lymphatic system. Different kinds of carcinomas include breast cancer, cervical cancer, prostate cancer, lung cancer, colon cancer, liver cancer, and skin cancer.

Carcinoma is one of four types of cancer. The other types are cancer in muscle, connective, or bone tissue (sarcoma), cancer in blood forming, or vascular, tissues (lymphoma, leukemia, and myeloma), and cancer in nerve tissues (neuroma, glioma, and neuroblastoma).

Diagnostic techniques include endoscopy, pap test, blood tests, biopsy, and imaging techniques such as X rays, CT scans (X rays that give a three-dimensional image), magnetic resonance imaging (MRI), and ultrasound imaging.

The most common cancer treatments are surgery, chemotherapy, and radiation therapy. Since chemotherapy kills some normal cells at the same time that it kills cancerous ones, it can cause many side effects, including hair loss, mouth sores, nausea, vomiting, diarrhea, and fatigue. People undergoing chemotherapy are especially susceptible to infection because the drugs severely limit the effectiveness of the immune system. Side effects of radiation may include hair loss, nausea, loss of appetite, and moderate to extreme fatigue.

Breast Cancer

Breast Cancer, malignant tumor in the glandular tissues of the breast. Such tumors, also called carcinomas, form when the processes that control normal cell growth break down, enabling a single abnormal cell to multiply at a rapid rate. Carcinomas, which tend to destroy an increasing proportion of normal breast tissue over time, may spread, or metastasize, to other parts of the body.

Scientists do not understand exactly what causes breast cancer. Studies suggest that several categories of women are at increased risk for the disease: those with a long menstrual history (menstrual periods that started before age 12 and ended after age 50); those who never gave birth or who waited until after age 30 to have children; and those who have used birth control pills or hormone replacement therapy. Such risk factors, all of which relate to hormone-based life events, suggest that breast cancer is somehow affected by prolonged exposure to female sex hormones, such as estrogen.

X-ray examination of the breasts, a technique called mammography, can increase the odds for successful treatment by detecting tumors in an early stage, before they are large enough to be felt. Although studies provide conflicting results about the effectiveness of mammography in reducing breast cancer deaths, it is recommended that women over age 40 should have a mammogram every year. A mammogram cannot distinguish a benign tumor from a malignant tumor. The only way to make a positive diagnosis on a suspect lump in the breast is by having a biopsy, a minor surgical procedure in which the lump or part of the lump is removed and examined under a microscope for cancer cells.

Treatment of breast cancer depends on a woman’s age and health as well as the type, extent, and location of the tumor, and if the cancer has remained in the breast or has spread to other parts of the body. Treatment may include surgery, radiation, chemotherapy, hormone therapy, or a combination of treatments.

Biopsy

Biopsy, surgical removal of living body tissue for study and diagnosis with a microscope. Biopsies are performed on organs to analyze the cause and nature of disease, and on tumors, or abnormal tissue growths, to determine if they are a type of cancer. For patients diagnosed with certain diseases, follow-up biopsies are used to study the effectiveness of a chosen course of medical treatment. Biopsies are vital in diagnosing and monitoring a wide range of illnesses, including muscular dystrophy, characterized by gradual wasting away of skeletal muscle, and Crohn’s disease, the chronic inflammation of the intestines.

An external biopsy specimen is taken by cutting or scraping a piece of tissue from an affected area of skin. When a sample is needed from an area well below the surface of the skin, the procedure is called internal biopsy, and viewing techniques such as ultrasound or computer axial tomography are often used to help the physician guide a hollow needle to the exact location.

In a procedure called aspiration biopsy, a needle is attached to a hypodermic syringe. A tissue sample is collected in the barrel of the syringe by using the suction that is created when the plunger of the syringe is pulled out. In a needle biopsy, the tissue sample is collected by rotating the needle, trapping a small but sufficient amount of tissue within the needle itself. In a punch biopsy, a sharp-edged instrument is used to recover a round piece of tissue from a specific depth below the skin.

Beriberi

Beriberi, diet-deficiency disease caused by a lack of vitamin B1. Chronic deficiency is known to cause two distinct forms of beriberi. When associated with low calorie intake and inactivity, the disease tends to affect the nervous system. This form, termed dry beriberi, is characterized by neuritis in the lower extremities, often with muscle atrophy, poor coordination, and eventually paralysis. The second form of beriberi, known as wet beriberi, is usually associated with extremely high activity levels and a high carbohydrate intake. Symptoms of wet beriberi include sweating, warm skin, and elevated heart rate; heart failure and death may follow.

Beriberi is especially prevalent in those parts of the world where the diet consists mainly of polished rice. Recovery is complete in about 50 percent of cases when adequate amounts of vitamin B1 are restored to the diet.

Anorexia Nervosa

Anorexia Nervosa, mental illness in which a person has an intense fear of gaining weight and a distorted perception of their weight and body shape. People with this illness believe themselves to be fat even when their weight is so low that their health is in danger. A person with anorexia nervosa severely restricts food intake and usually becomes extremely thin.

People with anorexia nervosa—who are sometimes known as anorectics or anorexics—have a preoccupation with food, weight, dieting, and body image. They are dissatisfied with their bodies, perceive themselves to be fat regardless of their actual weight, and are obsessed with becoming thin. Many are so focused on outward appearance that they have little awareness of internal sensations such as hunger and fullness. Anorexics usually undertake strict diets, severely restricting food intake and avoiding certain foods they deem taboo. They may also undergo intense, strenuous exercise regimens and weigh themselves frequently.

Addiction

Addiction, habitual repetition of excessive behavior that a person is unable or unwilling to stop, despite its harmful consequences. People can be physically addicted to a drug, meaning they may suffer ill physical effects if they stop taking the drug. They also can be psychologically addicted to drugs, gambling, or other behaviors, meaning they feel overwhelmingly deprived if they attempt to stop.

Diarrhea

Diarrhea, frequent passage of abnormally loose, watery stool. Diarrhea usually develops suddenly and may last from several hours to a few days. It is often accompanied by abdominal pains, low fever, nausea, and vomiting. If the attacks are severe or increasingly frequent, exhaustion and dehydration can result. In normal digestion the large intestine absorbs excess water from liquid food residues produced by earlier phases of the digestive process before excreting semisolid stools. When the mucous membrane lining the large intestine is irritated or inflamed, food residues move through the large intestine too quickly and the resulting stool is watery because the large intestine cannot absorb the excess water.

Diarrhea is not a disease. It is a symptom of numerous disorders, such as food poisoning from contaminated foods or beverages, infections by viruses and bacteria, or anxiety. Chronic diarrhea, which lasts weeks or months, may be caused by amoebic dysentery (intestinal infection), tumors, and other serious intestinal disorders such as Crohn’s disease, ulcerative colitis, or irritable bowel syndrome. Except in the case of irritable bowel syndrome, the stool may contain blood or pus.

The usual treatment for diarrhea consists of bed rest, drinking liquids to replace fluids and salts lost from the body, and eating soft foods. Dehydration is a serious concern in infants and the elderly. If the condition lasts more than a few days, a physician should be consulted.