THIS CANCER IS CHARACTERIZED BY ABNORMAL GROWTH OF CELLS IN THE UTERUS

Uterine Cancer

Introduction

A disease characterized by the abnormal growth of cells in the uterus. Cancers affecting the lining of the uterus (endometrium) are the most common cancers of the female reproductive tract. Other uterine cancers, called uterine sarcomas, develop from underlying muscle or connective tissue; they are much rarer. This article focuses on the development, diagnosis, and treatment of endometrial cancer.

Causes and symptoms

Although the causes of endometrial cancer vary and in many cases remain unknown, several factors have been identified that increase the risk of developing the disease. Many of these risk factors stem from an imbalance in which levels of the hormone estrogen in the uterus are regularly higher than levels of progesterone. Women who began their menstrual cycles at an early age (before 12 years) or who entered menopause late (after age 52) are at a higher risk for endometrial cancer, probably because of the increased exposure of the uterine wall to estrogen.

Other factors associated with increased exposure to estrogen include lack of a previous pregnancy, obesity, and estrogen replacement therapy following menopause. Women who have taken the breast cancer drug tamoxifen also appear to be at slightly higher risk of developing endometrial cancer, as are females with diabetes. Additional risk factors include race—whites are 70 percent more likely to develop uterine cancer than are blacks—a personal history of breast or ovarian cancer, age (over 40 years), and a family history of endometrial cancer.

The predominant early sign of endometrial cancer is vaginal bleeding or other discharge, especially in postmenopausal women. Any such discharge should be brought to the attention of a physician immediately. Additional possible symptoms are unexplained pelvic pain, a discernible lump or mass, and weight loss.

Diagnosis and prognosis

A biopsy may be used to take samples of uterine tissue, or dilatation and curettage (D & C) may be used to scrape endometrial cells from the wall of the uterus for examination. Cancers of the uterus and surrounding tissues can also be detected by observing the reproductive, digestive, and urinary tracts with specialized viewing scopes. Internal imaging procedures often allow a more precise location and determination of the potential spread of uterine cancer. 

Methods include X rays, computed tomography (CT) scans, magnetic resonance imaging (MRI), and ultrasound. An X-ray procedure called an intravenous pyelogram uses an injected iodine solution to enhance a series of images taken of the urinary tract in cases where spread of cancer to these tissues is suspected.

Once uterine cancer has been diagnosed, its stage is then determined to indicate how far the cancer has progressed. Stage I cancers are localized to the main body of the uterus, whereas stage II tumours have spread to the cervix. Stage III cancers have spread outside the uterus to the vagina, regional lymph nodes, or peritoneum but are still contained within the pelvis. Stage IV cancers have spread to distant organs such as the lungs, bone, bladder, or digestive tract.

Five-year survival for endometrial cancer is quite high when the cancer is diagnosed early, even among patients whose cancer has spread to the cervix. If the cancer has spread beyond the endometrium but remains confined to the pelvis, five-year survival is roughly 50 percent. However, once the cancer has metastasized to other organs, the five-year survival rate is very low.

Treatment

Surgery is used to treat most endometrial cancers. A simple hysterectomy removes the uterus and cervix, whereas a radical hysterectomy also removes underlying connective tissue (the parametrium) and ligaments along with the upper portion of the vagina. Either of these surgeries may be done in conjunction with the removal of the fallopian tubes and ovaries. 

Surgical removal of the uterus or ovaries results in infertility, and removal of the ovaries will also cause women to go immediately into menopause. Lymph nodes may also be removed during surgery. Radiation therapy is sometimes used in conjunction with surgery. External beam radiation resembles traditional X rays in that the radiation is directed from outside the body toward an internal target tissue. In brachytherapy radioactive rods or pellets are implanted to focus the radiation on the cancer and greatly reduce side effects. 

Side effects of pelvic radiation therapy may include diarrhea, fatigue, premature menopause, bladder irritation, or narrowing of the vagina due to scar tissue buildup.

In cases where endometrial cancer has spread beyond the uterus, general or systemic approaches such as chemotherapy may be required so that as many cancerous cells as possible can be sought out and destroyed. Some uterine cancers can be treated in part by using hormonal therapy. If the cancer cells are found to contain a protein called the progesterone receptor, the hormone progesterone may be used to slow the growth of the tumour.

Prevention

Long-term use of oral contraceptives (birth control pills) reduces the risk of endometrial cancer. Regular exams may reveal benign growths in the uterine wall called hyperplasias, which can be removed to eliminate the possibility of their developing into malignant tumours. Some medical societies recommend an annual Pap test plus pelvic exam for all women once they have reached 18 years of age or become sexually active, whichever is earlier.

ALL YOU NEED TO KNOW ABOUT THIS CANCER

 Prostate Cancer

Introduction

Disease characterized by uncontrolled growth of cells within the prostate gland, a walnut-sized organ surrounding the urethra just below the bladder in males. Worldwide among males, the incidence of prostate cancer is surpassed only by lung and stomach cancers; among North American men, only skin cancer occurs more often.

Prostate cancer is rare in men below the age of 50, and in North America the disease is twice as common in black men as it is in whites. Prostate cancer should not be confused with benign prostate hyperplasia, which has similar symptoms and occurs often in older men but is not a type of cancer.

Causes and symptoms

When the prostate gland becomes cancerous, it can put pressure on the urethra, causing frequent or painful urination. Such pressure can also cause difficulty in urinating, a weak and intermittent urine flow, or blood in the urine. The cancerous growth may also put pressure on the nerves required for erection, causing impotence or sexual dysfunction. Other symptoms of prostate cancer include swollen lymph nodes in the groin and pain in the pelvis, hips, back, or ribs.

As in most cancers, the causes of prostate cancer are varied, though most cases are thought to be related to the male hormone androgen. The likelihood of a man's developing prostate cancer doubles if a parent or sibling has had prostate cancer; this suggests that genetic factors play a role. Two genes, known as BRCA1 (breast cancer type 1) and BRCA2 (breast cancer type 2), have been linked to prostate cancer. As their names imply, they are commonly found in mutated forms in some women with breast cancer. However, studies have shown that men carrying mutations in BRCA2 have an increased risk of developing prostate cancer, and mutations in either gene can significantly reduce survival.

Diagnosis

Prostate cancers usually grow very slowly, and individuals may not display symptoms for some time. If the prostate is enlarged, preliminary diagnosis can be made by rectal examination or transrectal ultrasound (TRUS). A blood test for prostate-specific antigen (PSA) is used to detect prostate tumours in their earliest stages. If any of these tests suggest cancer, a biopsy is done to confirm the diagnosis. When caught early, prostate cancer is treatable. A large majority of prostate cancers are diagnosed either before they have spread or when they have spread only locally. Survival rates in these cases are very high.

Treatment

Because prostate cancers usually progress slowly, a physician may recommend a “watchful waiting” approach rather than immediate treatment. This is especially true for patients who are elderly or in otherwise poor health. If treatment is required, the physician may use surgery, radiation, hormone therapy, chemotherapy, or a combination of two or more of these approaches. 

Surgery is usually done only if the cancer has not spread from the prostate. The removal of the entire prostate plus some surrounding tissues (radical prostectomy) may be considered if examination of the pelvic lymph nodes reveals that they are not cancerous. Surgical risks include impotence and urinary incontinence. A second surgical procedure, transurethral resection of the prostate (TURP), is used to relieve symptoms but does not remove all of the cancer. TURP is often used in men who cannot have a radical prostectomy because of advanced age or illness or in men who have a noncancerous enlargement of the prostate.

 In men who are unable to have traditional surgery, cryosurgery may also be used. In this procedure, a metal probe is inserted into the cancerous regions of the prostate; liquid nitrogen is then used to freeze the probe, killing the surrounding cells.

If the cancer has spread from the prostate, radiation therapy may be used. Hormone therapy attacks the male hormones (androgens) that often stimulate the growth of prostate cancer. 

A form of hormone therapy involves drugs called LHRH analogs, or LHRH agonists, that chemically block the production of androgens. Side effects of hormone therapy may include reduced libido, abnormal growth or sensitivity of the breasts, and hot flashes. Orchiectomy, or removal of the testes, cuts off the tumour's supply of testosterone. This surgery can delay or stop tumour growth and eliminates the need for hormone therapy. 

If surgery or hormone therapy fails, chemotherapy may be used. Chemotherapy employs drugs that kill dividing cells (i.e., cancer cells) but is not highly effective in treating prostate cancer. It can, however, slow the growth of the tumour.

Other drugs, called antiandrogens, block the activity of androgens and are often used in combination with other forms of hormone therapy. An antiandrogen called abiraterone inhibits the activity of an enzyme involved in testosterone synthesis in the testes and adrenal glands. 

In clinical trials, abiraterone has shown promise in treating patients with aggressive end-stage prostate cancer, which is usually refractory to hormone therapy and is often fatal. Treatment with abiraterone is associated with reductions in tumour size and PSA levels. Its side effects appear to be limited primarily to hypertension, edema, and potassium deficiency.

Prevention

Risk factors for prostate cancer such as age, race, or family history cannot be avoided. However, studies have suggested that a diet low in fats and high in fruits and vegetables decreases prostate cancer risk. Compounds called lycopenes, which are present in grapefruit, tomatoes, and watermelon, have been linked to reduced risk, as has the nutrient selenium, which is found in nuts, oranges, and wheat germ.

 Physicians disagree on the usefulness of routine screening for prostate cancer. Most medical societies and government agencies feel that screening has not proved to reduce prostate cancer mortality and therefore do not recommend screening. Some medical societies, however, recommend an annual PSA test and digital rectal examination at age 50 for most men and at age 45 for men at higher risk.

STOMACH CANCER: is deadly to body system

Cancer Information

Introduction

Stomach cancer also refers to gastric cancer is a disease characterized by abnormal growth of cells in the stomach. The incidence of stomach cancer has decreased dramatically since the early 20th century in countries where refrigeration has replaced other methods of food preservation such as salting, smoking, and pickling. Stomach cancer rates remain high in countries where these processes are still used extensively.

Causes and symptoms

Ninety-five percent of malignant stomach cancers develop from epithelial cells lining the stomach. These tumours are called adenocarcinomas. Other stomach cancers can develop from the surrounding immune cells, hormone-producing cells, or connective tissue. Multiple risk factors have been identified that increase a person's probability of developing this cancer. 

These include a diet high in salted, smoked, or pickled foods, tobacco and alcohol use, or a family history of stomach cancer. Infection by the bacterium Helicobacter pylori, which can cause significant damage to gastric tissues and is a cause of peptic ulcers, can also lead to stomach cancer. Other factors that may increase the risk of stomach cancer to varying degrees are previous stomach surgery, blood type A, advanced age (60–70 years), or chronic stomach inflammation. 

Males develop stomach cancer at approximately twice the rate of females. Rare disorders such as pernicious anemia or Menetrier disease and congenital disorders that lead to increased risk for colorectal cancer may also increase stomach cancer risk.

The symptoms of stomach cancer are prevalent in many other illnesses and may include abdominal pain or discomfort, unexplained weight loss, vomiting, poor digestion, or visible swelling in the abdomen.

Diagnosis

No specific laboratory test for stomach cancer exists, and the disease is therefore usually diagnosed through a combination of visual means. A physician can inspect the lining of the stomach with a flexible, lens-containing tube called an endoscope. The endoscope can also be used to take samples from potentially cancerous tissues for biopsy. These samples are examined under a microscope for signs of cancer. An endoscope may also be modified with a special probe that emits sound waves in the stomach, which allows the physician to create an image of the stomach wall. X rays are also employed, usually after the patient has swallowed a barium compound that coats the stomach and provides better image contrast. Other imaging techniques such as computed tomography (CT) scans and magnetic resonance imaging (MRI) are also used, especially when the cancer is believed to have spread.

          

Once stomach cancer has been diagnosed, its stage is determined. The stage is an indicator of how far the cancer has progressed. Staging for stomach cancer is complicated and is based on a combination of how far the cancer has grown through the stomach wall and on the number of lymph nodes affected, if any. Stage 0 stomach cancer is also called carcinoma in situ and is confined to the epithelial cells that line the stomach. Stage I and stage II cancers have spread into the connective tissue or muscle layers that underlie the epithelial cells, but they have reached fewer than six nearby lymph nodes. Stage III and IV cancers are more advanced and may have metastasized to distant tissues.

A very high percentage of individuals survive stomach cancer for at least five years if the cancer is diagnosed very early, and many of them go on to live long, healthy lives. Unfortunately, only a small percentage of stomach cancers are identified and treated at such an early stage. At the time when most lower-stomach cancers are diagnosed, roughly half the patients survive for at least five years. Cancers of the upper stomach have a lower survival rate, and if the cancer has spread to distant tissues in the body, the survival rate is extremely low.

Treatment

Surgery is the only method available for curing stomach cancer, although radiation or chemotherapy may be used in conjunction with surgery or to relieve symptoms. If the cancer is localized, the cancerous portions of the stomach are removed in a procedure called a partial gastrectomy. In some cases, the entire stomach must be removed along with the spleen and nearby lymph nodes. Repair of the stomach generally requires permanent changes in dietary habits and may demand intravenous administration of vitamin supplements. 

          

If a cancer cannot be cured, surgery may still be used to relieve symptoms or digestive discomfort. Radiation therapy is sometimes used in conjunction with surgery to destroy any remaining cancer cells. When stomach cancer has spread to distant organs, chemotherapy may be required so that as many cancer cells as possible can be sought out and destroyed. Both radiation therapy and chemotherapy may produce several side effects such as vomiting and diarrhea.

Prevention

Stomach cancer cannot be completely prevented, but people can decrease their risk of disease by adopting a diet that is low in salted, smoked, and pickled foods and high in fruits and vegetables. Elimination of tobacco use and reduction in alcohol consumption also help lower risk. Research has indicated that prompt treatment of H. pylori infection can reverse gastric tissue damage, thereby reducing stomach cancer risk.

TESTICULAR CANCER:all you need to know about this cancer

Cancer Information

Introduction

Disease characterized by uncontrolled growth of cells within the testis, the reproductive organ that produces sperm. Although testicular cancer represents only 1 percent of all cancers, it is the most common malignancy for men between the ages of 20 and 34. It most often affects men between 15 and 39 years of age. In the United States, approximately 7,500 new cases are diagnosed each year.

Testicular cancers are broadly classified as seminomas or nonseminomas based on their appearance and other characteristics. About 30 percent of testicular cancers are seminomas, and they tend to respond well to treatment. Nonseminomas, including yolk-sac tumours, embryonal carcinomas, and choriocarcinomas, are generally less responsive to treatment than seminomas. Typically, more than one type of nonseminoma will be present within the same tumour.

    

Causes and symptoms

Most cases of testicular cancer arise in individuals who have no known risk factors for the disease. An important known risk factor is a developmental abnormality that consists of a failure of one or both testes to descend into the scrotum, which normally takes place around the time of birth. The abnormality, called cryptorchidism, occurs in up to 10 percent of one-year-old boys, and it is associated with a 5- to 10-fold increased risk of testicular cancer, even if the condition is corrected with surgery.

Testicular cancer is typically noticed by the patient as a painless lump in either testis. This lump can be associated with swelling of the scrotum, pain and discomfort in the scrotum, or a dull ache in the lower abdomen. Because these symptoms are not specific to cancer, they should be investigated by a physician.

Diagnosis and prognosis

The initial investigation of a suspicious lump may involve blood tests and imaging studies. Different types of testicular cancer are associated with an increase in specific substances in the blood, including alpha fetoprotein, human chorionic gonadotropin, and lactate dehydrogenase. Ultrasound may be used to determine the size and location of a tumour in a testis and may help distinguish cancer from a benign condition. Ultimately, diagnosis of cancer requires removal of the testis and examination of the tissue under a microscope.

The prognosis depends on the type of testicular cancer found and the extent to which it has spread. Both types tend to metastasize first to the local lymph nodes of the pelvis and subsequently to distant sites such as the lungs. Seminomas have a cure rate greater than 95 percent when detected early. Nonseminomas tend to spread more quickly and behave more aggressively than seminomas, but they can be cured in more than 90 percent of cases.

 A dramatic increase in the cure rate, particularly for patients with nonseminomas, has been achieved largely through improved chemotherapy introduced in the mid-1970s.

Treatment

As with many cancers, treatment involves a combination of surgery, chemotherapy, and radiation therapy, depending on the type and spread of the original cancer. Virtually all testicular cancer is diagnosed and treated initially by surgically removing the affected testis (orchiectomy). 

Fortunately, the removal of one testis usually does not affect fertility. If the cancer has spread into the pelvic region or beyond, radiation or chemotherapy may be added to the treatment. Seminomas tend to respond very well to radiation therapy alone, even after the cancer has spread into the pelvis. Nonseminomas often require the addition of chemotherapy.

Prevention

Undescended testes are usually moved into the scrotum surgically before puberty to help prevent the development of cancer. Otherwise, regular self-examination and physical examination by a physician for testicular cancer can lead to early detection, which provides the best opportunity for a cure

All you need to know about lung cancer

Cancer Information

The alveoli and capillaries in the lungs exchange oxygen for carbon dioxide. Imbalances in the exchange of these gases can lead to dangerous respiratory disorders, such as respiratory acidosis or hyperventilation. In addition, accumulation of fluid in the alveolar spaces can interfere with gas exchange, causing symptoms such as shortness of breath

Introduction

Disease characterized by uncontrolled growth of cells in the lungs. Lung cancer was first described by doctors in the mid-19th century. In the early 20th century it was considered relatively rare, but by the end of the century it was the leading cause of cancer-related death among men in more than 25 developed countries. In the United States it has surpassed breast cancer as the leading cause of death from cancer among women. This rapid increase is due mostly to the increased use of cigarettes since World War I.

Causes and symptoms

Lung cancer occurs primarily in persons between 45 and 75 years of age. In countries with a prolonged history of cigarette smoking, between 80 and 90 percent of all cases are caused by smoking. Heavy smokers have a greater likelihood of developing the disease than do light smokers. The risk is also greater for those who started smoking at a young age.

Passive inhalation of cigarette smoke (sometimes called second hand smoke) is linked to lung cancer in non smokers. In the early 1990s it was estimated that passive smoking caused some 2,500 to 3,300 lung cancer deaths each year in the United States, or about 2 percent of all U.S. lung cancer deaths. Other risk factors include exposure to radon gas and asbestos; smokers exposed to these substances run a greater risk of developing lung cancer than do non smokers. Uranium and pitchblende miners, chromium and nickel refiners, welders, and workers exposed to halogenated ethers also have an increased incidence, as do some workers in hydrocarbon-related processing, such as coal processors, tar refiners, and roofers. Lung cancer is rarely caused directly by inherited mutations.

Tumours can begin anywhere in the lung, but symptoms do not usually appear until the disease has reached an advanced stage or spread to another part of the body. The most common symptoms include shortness of breath, a persistent cough or wheeze, chest pain, bloody sputum, unexplained weight loss, and susceptibility to lower respiratory infections. In cases where the cancer has spread beyond the lungs, visible lumps, jaundice, or bone pain may occur.

Diagnosis

Lung cancers are often discovered during examinations for other conditions. Cancer cells may be detected in sputum; a needle biopsy may be used to remove a sample of lung tissue for analysis; or the large airways of the lungs (bronchi) can viewed directly with a bronchoscope for signs of cancer. Non invasive methods include X rays, computed tomography (CT) scans, positron emission tomography (PET) scans, and magnetic resonance imaging (MRI).

Most cases are usually diagnosed well after the disease has spread (metastasized) from its original site. For this reason, lung cancer has a poorer prognosis than many other cancers. Even when it is detected early, the five-year survival rate is about 50 percent.

Types of lung cancer

Once diagnosed, the tumour's type and degree of invasiveness are determined. There are two basic forms: small-cell carcinoma, which accounts for 20–25 percent of all cases, and non-small-cell carcinoma, which is responsible for the remainder.

Small-cell carcinoma

Small-cell carcinoma (SCLC), also called oat-cell carcinoma, is rarely found in people who have never smoked. It is characterized by cells that are small and round, oval, or shaped like oat grains. SCLC is the most aggressive type of lung cancer; because it tends to spread quickly before symptoms become apparent, the survival rate is very low.

Non-small-cell carcinomas

Non-SCLCs consist primarily of three types of tumour: squamous cell carcinoma, adenocarcinoma, and large-cell carcinoma.

Adenocarcinoma accounts for some 25 to 30 percent of cases worldwide, but it is the most common type of lung cancer in the United States. Cells of adenocarcinoma are cube- or column-shaped, and they form structures that resemble glands and are sometimes hollow. Tumours often originate in the smaller, peripheral bronchi. Symptoms at the time of diagnosis often reflect invasion of the lymph nodes, pleura, and both lungs or metastasis to other organs.

Some 25 to 30 percent of primary lung cancers are squamous cell carcinomas, also called epidermoid carcinomas. This tumour is characterized by flat, scale like cells, and it often develops in the larger bronchi of the central portion of the lungs. Squamous cell carcinoma tends to remain localized longer than other types and thus is generally more responsive to treatment.

About 10 percent of all lung cancers are large-cell carcinomas. There is some dispute as to whether these constitute a distinct type of cancer or are merely a group of unusual squamous cell carcinomas and adenocarcinomas. Large-cell carcinomas can begin in any part of the lung and tend to grow very quickly.

Treatment

As with most cancers, treatments for lung cancer include surgery, chemotherapy, and radiation. The choice of treatment depends on the patient's general health, the stage or extent of the disease, and the type of cancer. The type of treatment an individual patient receives may also be based on the results of genetic screening, which can identify mutations that render some lung cancers susceptible to specific drugs.

Surgery involves the removal of a cancerous segment (segmentectomy), a lobe of the lung (lobectomy), or the entire lung (pneumonectomy). Lung surgery is serious and can lead to complications such as pneumonia or bleeding. Although removal of an entire lung does not prohibit otherwise healthy people from ultimately resuming normal activity, the already poor condition of many patients' lungs results in long-term difficulty in breathing after surgery.

Radiation may be used alone or in conjunction with surgery—either before surgery to shrink tumours or following surgery to destroy small amounts of cancerous tissue. Radiation treatment may be administered as external beams or surgically implanted radioactive pellets (brachytherapy). Side effects include vomiting, diarrhoea, fatigue, or additional damage to the lungs. Chemotherapy uses chemicals to destroy cancerous cells, but these chemicals also attack normal cells to varying degrees, causing side effects that are similar to radiation therapy. An experimental technology that has shown promise in the treatment of lung cancer is microwave ablation, which relies on heat derived from microwave energy to kill cancer cells. Early studies in small subsets of patients have demonstrated that microwave ablation can shrink and possibly even eliminate some lung tumours.

Tissue from (left) a nonsmoker's lung and (right) a smoker's lung.

Prevention

The probability of developing lung cancer can be greatly reduced by avoiding smoking. Smokers who quit also reduce their risk significantly. Testing for radon gas and avoiding exposure to coal products, asbestos, and other airborne carcinogens also lowers risk.