Cancers (Carcinomas)

(Renal cell carcinoma; renal pelvic carcinoma; Wilms' tumor)

Kidney cancer is relatively uncommon in the United States, accounting for about 29,000 new cases and 12,000 deaths a year. In patients of all ages, males outnumber females about two to one. There are several types of kidney cancer; the most common are: Renal cell carcinoma, which most often originates in the nephrons, the filtering units of the kidney, and accounts for 85 percent of cases. This cancer can strike at any age, but it most common between ages 40 and 60. Cancer of the renal pelvis, which starts in the central part of the kidney, and frequently spreads to the ureter, the tube that carries urine from the kidney, and to the bladder. Wilms' tumor, a rare childhood malignancy, which usually occurs before the age of five years and often spreads to other abdominal organs. Wilms' tumor is quite different from adult kidney cancer. It produces a large abdominal swelling that grows rapidly. There may also be a low-grade fever, weight loss, fatigue, and other symptoms.

Bladder cancer is any malignancy of the urinary bladder. Each year, more than 50,000 Americans are diagnosed with the disease, which causes about 11,000 deaths. Men outnumber women three to one, and the incidence is higher among whites than other races.

(Ewing's and other sarcomas)

Bone cancer is a relatively rare malignancy that can occur at any age, but more often it seems to strike during childhood or adolescence.

Breast cancer is the most common malignancy in women, and second only to lung cancer in female cancer mortality. Presently, about one in nine American women develops this disease at some time in her life, compared to one in 17 in 1950. Experts are uncertain whether this represents a true rise in the incidence of breast cancer or improved detection of it due to mammography and better public awareness.

After decades of decline, the incidence of cervical cancer is again on the rise, especially in women under age 50. According to the American Cancer Society, about 80,000 women are now diagnosed with cervical cancer each year, but the malignancy is invasive in only 16,000 of these cases. (Invasive cancer may cause unusual vaginal bleeding, a watery discharge, and dull pelvic pain.) The remaining 65,000 have carcinoma in situ, an asymptomatic preinvasive condition.

Cancer of the colon and rectum is the second most common malignancy in the United States (surpassed only by lung cancer), with about 138,000 new cases and 55,000 deaths a year. Even so, death rates from colorectal cancer have fallen by 29 percent in men and 7 percent in women over the past 30 years, and recent progress promises further reductions in mortality.

The gallbladder, a small organ under the liver, stores the bile juices manufactured by the liver and released during digestion. If it becomes cancerous, there may be no symptoms early on. Later, however, abdominal pain, jaundice, loss of appetite, weight loss, and widespread itching may develop. These symptoms are often mistakenly thought to indicate liver disease.

(Adenocarcinoma, Carcinoid, Intestinal Lymphoma, Leiomyosarcoma)

Intestinal cancer usually refers to a malignancy of the small intestine. It is relatively rare in the United States, with only about 3,600 new cases a year. (In contrast, cancer of the colon, or large intestine, is second only to lung cancer in prevalence.) When intestinal cancer does occur, it is often in conjunction with other disorders. For example, persons with inflammatory bowel disease have an increased risk of adenocarcinoma, a cancer in which the malignant cells function like glands and produce hormones, mucus, or other glandular substances.

With cancer of the larynx, or voice box, malignant cells develop in or near the vocal cords. The disease usually occurs after age 55; males with this cancer outnumber females four to one. The condition is most common among smokers, and those who also consume large amounts of alcohol suffer the highest incidence. Some studies have suggested that long-term asbestos exposure may also increase the risk.

Leukemia, a term used to describe several types of blood cancer, comes from the Greek words for "white blood". The name refers to the whitish or pale-pink blood leukemia patients have because of high numbers of abnormal white cells. Although leukemia affects all types of blood cells, as well as bone marrow and other blood-producing structures, the white cells, or lymphocytes, are involved the most.

Cancer that originates in the liver is relatively rare in the United States; worldwide, however, it is one of the most common malignancies. The precise cause of the cancer is unknown, but chronic hepatitis is a major precipitating factor, as is cirrhosis, a disease in which scar tissue replaces normal liver cells. Other contributing factors include occupational exposure to vinyl chloride and similarly toxic chemicals, the use of synthetic testosterone and other anabolic steroids to build muscle mass, and alcoholism. Because liver cancer is more prevalent in sub-Saharan Africa and the Far East, some experts theorize that environmental and cultural factors play a strong role in its development.

Lung cancer is any malignancy that originates in the lungs, in contrast to cancers that arise elsewhere and then spread to the lungs, as many do. It is the most common fatal malignancy in the United States, with about 170,000 new cases annually, and accounting for 153,000 deaths every year.

(Hodgkin's Disease; Non-Hodgkin's Lymphoma; Burkitt's Lymphoma)

Lymphomas are malignant tumors of the lymph system, the network of nodes and glands that produce infection-fighting substances. In the United States, there are about 58.000 new cases each year.
The most common general symptom is a painless enlargement of one or more lymph nodes in the neck, groin, or armpit. Additional indications of Hodgkin's disease include a chronic low-grade fever and night sweats. Some people with non-Hodgkin's lymphoma also develop skin rashes, enlarged tonsils, and abdominal swelling.

Melanoma, the most lethal form of skin cancer, develops when pigment-producing cells (melanocytes) undergo malignant changes. Unlike other types of skin cancer, melanoma frequently metastasizes, spreading to the lungs, brain, liver, or other internal organs.

The incidence of melanoma has increased about 4 percent every year since 1973. In 1995, there were more than 34,500 new cases and over 7,000 deaths. Excessive sun exposure is by far the leading cause, especially among light-skinned people who sunburn easily. Heredity is also thought to play a part, and so is occupational exposure to coal tar, pitch, creosote, arsenic compounds, and radium.

Ovarian cancer is the most lethal malignancy of the female reproductive organs. According to the American Cancer Society, about 27,000 new cases are diagnosed each year, with a death toll of almost 15,000. The high mortality rate is attributed to the fact that by the time ovarian cancer is detected, it usually has spread. The cause remains unknown, though it is believed that hereditary factors play a role because ovarian cancer tends to run in families.

The pancreas is an oblong, pear-shaped organ, about six inches long, that ties within a loop of the small intestine behind the stomach. The exocrine portion of the pancreas, the tissue in which digestive juices and enzymes are produced, is the site of 95 percent of all pancreatic cancers. These cancers typically originate in the ductal cells in the head of the pancreas.

With about 244,000 new cases in the United States each year, prostate cancer is the most common type of malignancy in men and, with 44,000 deaths a year, second only to lung cancer in male cancer mortality. According to the American Cancer Society, about 1 in 11 men develops prostate cancer, usually after age 65, and the risk becomes greater with age. International studies link a high-fat diet to increased risk, but what triggers the cancer is unknown. It appears that certain population groups are more vulnerable than others. For example, the incidence of prostate cancer among African-American men is 32 percent higher than in Caucasions.

(Basal Cell and Squamous Cell Carcinomas)

Skin cancer is by far the most prevalent malignancy in the United Slates, with more than 800,000 cases a year. The two most common forms are basal cell carcinoma, which arises in the lowest part of the epidermis, or surface layer of the skin, and squamous cell carcinoma, which originates in the cells that make up the skins outer surface. Both types are readily curable if detected early and treated properly.

Most stomach cancers are adenocarcinomas, malignancies that arise in the glandular cells that line the stomach and produce various hormones and mucus. Less common types are gastric lymphomas, tumors that form in the stomach's lymph tissue, and gastric sarcomas, which develop in connective tissue.

(Buccal Cavity Carcinoma; Esophageal Cancer; Head and Neck Cancer, Upper Aerodigestive Tract Carcinoma)

Cancers of the upper aerodigestive tract, which extends from the mouth and nasal passages to the stomach, are relatively rare, especially when compared with malignancies of the colon and other lower digestive organs. But cancers arising anywhere in the mouth and throat are especially devastating because of their effect on appearance and the ability to eat.

Thyroid cancer is by far the most common malignancy affecting the endocrine, or hormone-producing, system. Even so, it is relatively rare, with about 13,000 new cases and 1,000 deaths a year.

Hormones secreted by the thyroid, a butterfly-shaped gland whose two lobes rest over the front of the trachea (windpipe) in the lower neck, regulate metabolism (see Thyroid Disorders). The thyroid gland is highly sensitive to radiation, especially when exposure occurs in a person under age 21. This became evident when studies found a greatly increased incidence of thyroid cancer among people who underwent radiation treatment as children for such disorders as an enlarged thymus, chronic tonsillitis, and even acne, a practice that has been abandoned. About 10 percent of those receiving such treatments later developed thyroid cancer. Similarly, people accidentally exposed to radiation, such as the Marshall Island inhabitants who were under the fallout of an atomic bomb detonated on the atoll Bikini in 1954, also have an increased incidence of thyroid cancer.

For unknown reasons, the course of thyroid cancers varies dramatically according to age. When the malignancy develops before the age of 40 in men and 50 in women, it is rarely fatal, even if it is quite advanced. In contrast, the outlook is poor after the age of 50, with the disease progressing rapidly and resisting treatment.

Thyroid cancer typically starts as a small lump, or nodule, that a doctor can feel when palpating the gland. Sometimes the first obvious sign is an enlarged lymph node in the neck. As the primary thyroid tumor grows, it may encroach on surrounding organs, resulting in possible voice changes, paralysis of the vocal cords, and swallowing problems due to a narrowing of the esophagus.

Diagnostic Studies and Procedures

Most thyroid nodules are benign, but these can be hard to distinguish from those that ate cancerous. A thyroid scan using radioactive iodine can make the distinction, however, because benign, or hot, nodules produce hormones and lend to absorb more of the iodine than nodules that do not make hormones. These so-called cool nodules are more likely to be cancerous, but in either instance, a biopsy is needed to rule out malignancy.

Sometimes what feels like a nodule is actually a cyst, in which case an ultrasound examination may verify that it is. However, some cysts are mixtures of solid and cystic tissue, which can produce misleading results. Thus, only a biopsy can determine whether a thyroid lump is cancerous. This can be done by withdrawing tissue samples from the nodule using a hollow needle.

If cancer is confirmed, a CT scan or MRI may be ordered to detect arty spread to nearby organs. A lung X-ray may also be needed, as some thyroid cancers spread to the lungs.

Medical Treatments

Thyroid cancer is generally treated surgically, but the extent of the operation depends upon the patient's age and type of cancer. Removal of the suspicious nodules, perhaps along with treatment using radioactive iodine, may be enough in a young person. Most experts, however, advise removing half or all of the affected thyroid lobe, especially if the patient is over 50 or the tumor is large and has invaded nearby tissue. Some or all of the opposite lobe may also be removed. When all of the thyroid is removed -- a total thyroidectomy -- lifelong hormone replacement therapy will be needed.

In advanced cases, radiation treatments, either alone or combined with chemotherapy, can alleviate pain and other symptoms. A tracheostomy, an opening in the trachea, or windpipe, may be necessary to allow breathing if the cancer threatens to close the airway.

Occasionally, during surgery to remove the thyroid cancer, the parathyroid glands -- small clusters of tissue in the thyroid that produce hormones for controlling calcium metabolism -- are inadvertently destroyed. If this happens, additional hormone replacement is needed, although an experimental treatment to implant salvaged parathyroid tissue appears promising. Other possible complications of thyroid surgery include damage to the nerves that control the opening of the airway, making a permanent tracheostomy necessary, and speech problems that result from larynx nerve damage.

Alternative Therapies

No effective alternative therapies for thyroid cancer exist, other than meditation, imaging, deep breathing, and other relaxation therapies to control pain and stress.

Self-Treatment

Thyroid cancer itself cannot be self-treated, but preventive measures can be taken. As much as possible, avoid exposing the head and neck to radiation, especially during childhood. Because people with Hashimotos disease, a disorder in which the thyroid is chronically inflamed and gradually destroyed, have an increased risk of thyroid cancer, they should be diligent about having regular examinations.

Other Causes of Thyroid Symptoms

A goiter due to an over- or underactive thyroid can cause swelling of the gland.

A malignancy anywhere in the uterus or its lining is referred to as uterine cancer. However, the major forms are distinguished from each other by their site of origin and types of malignant cells. Cancer arising in the endometrium, the lining of the uterus, is now the most common gynecologic cancer in the United States, with about 33.000 new cases and 6,000 deaths a year. (In the early 1900s, cervical cancer was the most prevalent form of cancer of the reproductive organs, but widespread use of the pap smear to detect precancerous changes has greatly diminished this malignancy.)