Thursday, February 26, 2009
Risk
The role of hepatitis B virus (HBV) infection in causing liver cancer is well established. Several lines of evidence point to this strong association. As noted earlier, the frequency of liver cancer relates to (correlates with) the frequency of chronic hepatitis B virus infection. In addition, the patients with hepatitis B virus who are at greatest risk for liver cancer are men with hepatitis B virus cirrhosis (scarring of the liver) and a family history of liver cancer. Perhaps the most convincing evidence, however, comes from a prospective (looking forward in time) study done in the 1970's in Taiwan involving male government employees over the age of 40. In this study, the investigators found that the risk of developing liver cancer was 200 times higher among employees who had chronic hepatitis B virus as compared to employees without chronic hepatitis B virus!
Studies in animals also have provided evidence that hepatitis B virus can cause liver cancer. For example, we have learned that liver cancer develops in other mammals that are naturally infected with hepatitis B virus-related viruses. Finally, by infecting transgenic mice with certain parts of the hepatitis B virus, scientists caused liver cancer to develop in mice that do not usually develop liver cancer. (Transgenic mice are mice that have been injected with new or foreign genetic material.)
Friday, February 20, 2009
liver cancer
Cancers that start in the liver
Several types of cancer can start in the liver.
hepatocellular carcinoma: This is the most common form of liver cancer in adults. It begins in the hepatocytes the main type of liver cell. About 3 out of 4 cancers that start in the liver are this type. Most of the information in this article refers to hepatocellular cancer.
This type of cancer can have different growth patterns.
- Some begin as a single tumor that grows larger. Only late in the disease does it spread to other parts of the liver.
- This type of cancer may also begin in many spots throughout the liver, not as a single tumor. This is most often seen in people with cirrhosis and is the most common pattern seen in the United States.
Doctors can figure out the subtypes of hepatocellular cancer by looking at the cancer under a microscope. Most of these subtypes do not affect treatment or the patient's outlook. But one rare type, called fibrolamellar, has a much better outlook (prognosis) than other forms of liver cancer.
Liver cancer
Liver cancer is a cancer that starts in the liver. To understand liver cancer, it helps to know about how the normal liver looks and works.
The liver is the largest organ inside the body. It lies under your right ribs, just below the right lung. If you were to poke your fingers up under your right ribs, you would almost touch your liver.
The liver is shaped like a pyramid and is divided into right and left lobes. Unlike most other organs, the liver gets blood from 2 sources. The hepatic artery supplies the liver with blood that is rich in oxygen. The portal vein carries nutrient-rich blood from the intestines to the liver.
The liver has many vital functions you cannot live without:
- It breaks down and stores many of the nutrients absorbed from the intestine.
- It makes some of the clotting factors needed to stop bleeding from a cut or injury.
- It secretes bile into the intestine to help absorb nutrients.
- It plays an important part in removing toxic wastes from the body.
Saturday, February 14, 2009
Diagnosis
f a patient has symptoms that suggest kidney cancer, the doctor may perform one or more of the following procedures:
- Physical exam: The doctor checks general signs of health and tests for fever and high blood pressure. The doctor also feels the abdomen and side for tumors.
- Urine tests: Urine is checked for blood and other signs of disease.
- Blood tests: The lab checks the blood to see how well the kidneys are working. The lab may check the level of several substances, such as creatinine. A high level of creatinine may mean the kidneys are not doing their job.
- Surgery: In most cases, based on the results of the CT scan, ultrasound, andx,
-rays , the doctor has enough information to recommend surgery to remove part or all of the kidney. A pathologist makes the final diagnosis by examining the tissue under a microscope.
Risk
Kidney cancer develops most often in people over 40, but no one knows the exact causes of this disease. Doctors can seldom explain why one person develops kidney cancer and another does not. However, it is clear that kidney cancer is not contagious. No one can "catch" the disease from another person.
Research has shown that people with certain risk factors are more likely than others to develop kidney cancer. A risk factor is anything that increases a person's chance of developing a disease.
Studies have found the following risk factors for kidney cancer:
- Smoking: Cigarette smoking is a major risk factor. Cigarette smokers are twice as likely as nonsmokers to develop kidney cancer. Cigar smoking also may increase the risk of this disease.
- Obesity: People who are obese have an increased risk of kidney cancer.
- High blood pressure: High blood pressure increases the risk of kidney cancer.
- Long-term dialysis: Dialysis is a treatment for people whose kidneys do not work well. It removes wastes from the blood. Being on dialysis for many years is a risk factor for kidney cancer.
- Gender: Males are more likely than females to be diagnosed with kidney cancer. Each year in the United States, about 20,000 men and 12,000 women learn they have kidney cancer.
Saturday, February 7, 2009
Risk
Kidney cancer develops most often in people over 40, but no one knows the exact causes of this disease. Doctors can seldom explain why one person develops kidney cancer and another does not. However, it is clear that kidney cancer is not contagious. No one can "catch" the disease from another person.
Research has shown that people with certain risk factors are more likely than others to develop kidney cancer. A risk factor is anything that increases a person's chance of developing a disease.
Most people who have these risk factors do not get kidney cancer. On the other hand, most people who do get the disease have no known risk factors. People who think they may be at risk should discuss this concern with their doctor. The doctor may be able to suggest ways to reduce the risk and can plan an appropriate schedule for checkups.
Treatment
There are a number of ways to find a doctor for a second opinion:
- The patient's doctor may refer the patient to one or more specialists. At cancer centers, several specialists often work together as a team.
- The Cancer Information Service, at 1-800-4-CANCER, can tell callers about nearby treatment centers.
- A local or state medical society, a nearby hospital, or a medical school can usually provide the names of specialists.
- The American Board of Medical Specialties (ABMS) offers a list of doctors who have met specific education and training requirements and have passed a specialty examination. Their directory-the Official ABMS Directory of Board Certified Medical Specialists-lists doctors' names along with their specialty and their educational background. The directory is available in most public libraries. Also, ABMS offers this information by telephone and on the Internet. The toll-free telephone number is 1-866-ASK-ABMS (1-866-275-2267)
- The NCI provides a helpful fact sheet on how to find a doctor called "How To Find a Doctor or Treatment Facility If You Have Cancer." It is available on the Internet at http://cancer.gov/publications.
Treatment
The doctor may refer the patient to a specialist, or the patient may ask for a referral. Specialists who treat kidney cancer include doctors who specialize in diseases of the urinary system (urologists) and doctors who specialize in cancer (medical oncologists and radiation oncologists).
Treatment depends mainly on the stage of disease and the patient's general health and age. The doctor can describe treatment choices and discuss the expected results. The doctor and patient can work together to develop a treatment plan that fits the patient's needs.
Treatment
Treatment of kidney cancer
To plan the best treatment, the doctor needs to know the stage (extent) of the disease. The stage is based on the size of the tumor, whether the cancer has spread and, if so, to what parts of the body.
Staging may involve imaging tests such as an ultrasound or a CT scan. The doctor also may use an MRI. For this test, a powerful magnet linked to a computer makes detailed pictures of organs and blood vessels.
Doctors describe kidney cancer by the following stages:
- Stage I is an early stage of kidney cancer. The tumor measures up to 2 3/4 inches (7 centimeters). It is no bigger than a tennis ball. The cancer cells are found only in the kidney.
- Stage II is also an early stage of kidney cancer, but the tumor measures more than 2 3/4 inches. The cancer cells are found only in the kidney.
- Stage III is one of the following: The tumor does not extend beyond the kidney, but cancer cells have spread through the lymphatic system to one nearby lymph node; or The tumor has invaded the adrenal gland or the layers of fat and fibrous tissue that surround the kidney, but cancer cells have not spread beyond the fibrous tissue. Cancer cells may be found in one nearby lymph node; or The cancer cells have spread from the kidney to a nearby large blood vessel. Cancer cells may be found in one nearby lymph node.
- Stage IV is one of the following: The tumor extends beyond the fibrous tissue that surrounds the kidney; or Cancer cells are found in more than one nearby lymph node; or The cancer has spread to other places in the body such as the lungs.
- Recurrent cancer is cancer that has come back (recurred) after treatment. It may come back in the kidney or in another part of the body.