Friday, March 27, 2009
Types
Bones serve various purposes in the body. They protect and support the organs in the body. For instance, the brain is protected by the skull and the lungs are protected by the ribs. Blood cells are made and stored in the bone marrow, the spongy and soft tissue that many bone have in their center.
Primary bone cancer occurs most commonly in the legs and arms, although it can also affect other bones of the body. Primary bone cancers are usually referred to as sarcomas, of which there are several types. Each type of sarcoma affects a different type of bone tissue, with the most common being: chondrosarcoma; Ewing’s sarcoma; and osteosarcoma.
Chondrosarcoma: This type of bone cancer occurs mostly in adults. It affects the cartilage, which is the rubber-like tissue that is around the joints.
Ewing's sarcoma: This bone cancer occurs most often amongst people between the ages of 10-25, with teenagers being most affected. It affects the shaft, or middle part of large bones. It usually occurs in the long bones of the upper arm and thigh and also the hipbones. It can also affect the ribs.
Osteosarcoma: This is the most common kind of bone cancer and it affects young people in the age group of 10-25 years. Males are more susceptible to it compared to females. Osteosarcoma usually begins where new bone tissue forms, at the ends of bones, as young people grow. The long bones of the legs and arms are usually affected by it.
Cancers like the above, which start in the bone, occur rarely. However, it is quite common for cancers to spread from the other parts of the body to the bone. This type of cancer is known as metastatic cancer. Around 80% of the metastatic cancers that affect the bone are due to primary carcinomas that affect other organs such as the prostate, breast, kidney, lung, stomach, pancreas, and thyroid. Each of these types of metastatic cancers, which affect the bone, is named according to the tissue or organ where the primary cancer occurs.
Symptoms
The symptoms of bone cancer vary from one person to another according to the location and size of the bone cancer. Pain is one of the most common bone cancer symptoms. Generally, there is a gradual increase in the severity of the symptoms with time. At first, the pain may only be felt with activity or at night. According to the growth of the cancerous tumor, people may experience the symptoms for weeks, perhaps even months, sometimes even years until they seek medical help. Sometimes a lump or mass may occur either in the tissues that surround the bone or on the bone itself. This commonly occurs with fibrosarcoma or MFH, but can also occur with other types of bone tumors as well. Some of the less common bone cancer symptoms are weight loss, night sweats, chills, and fever. These symptoms usually occur when the cancerous tumor spreads to the other parts of the body.
Friday, March 20, 2009
Causes
The exact cause of most bone cancers is not known. But we do know that certain risk factors are linked to this disease. A risk factor is something that affects a person's chance of getting a disease. Some risk factors, such as smoking, can be controlled. Others, like a person's age or race, can't be changed. But having a risk factor, or even several, does not mean that you will get cancer. Most people with bone cancer do not have any known risk factors.
The risk factors for bone cancer are often linked to having had other diseases, treatments for other diseases, or age. The following conditions can slightly increase the risk of bone cancer. If you have any of these, you should ask your doctor for more information.
- Li-Fraumeni syndrome
- Rothmund-Thompson syndrome
- retinoblastoma (a rare eye cancer of children)
- Paget disease
- multiple exostoses, also called multiple osteochondromas (an inherited condition that causes many bumps on a person's bones)
- multiple enchondromatosis (many benign cartilage tumors)
Bone cancer has been reported in a few people who have had bone marrow (stem cell) transplantation.
Friday, March 13, 2009
Bone cancer
What is bone cancer
Bone is the supporting framework of the body. Most bones are hollow. The outer part of bones consists of a network of fibrous tissue called matrix onto which calcium salts are laid down. The soft tissue inside hollow bones is called bone marrow. At each end of the bone is a zone of, a softer form of bone-like tissue called cartilage.
Cartilage is made of a fibrous tissue matrix mixed with a gel-like substance that does not contain much calcium. Cartilage is softer than bone but more firm than most tissues.
Most bones start out as cartilage. The body then lays calcium down onto the cartilage to form bone. After the bone is formed, some cartilage may remain at the ends to act as a cushion between bones. This cartilage, along with ligaments and some other tissues connect bones to form a joint. In adults, cartilage is mainly found at the end of some bones as part of a joint. It is also seen at the place in the chest where the ribs meet the sternum (breastbone) and in parts of the face. The trachea (windpipe), larynx (voicebox), and the outer part of the ear are other structures that contain cartilage.
Types of liver cancer
Types of liver cancer
Some cancers begin in the cells of the liver itself – these are called primary liver cancer. More commonly, cancers start in cells in other organs of the body but then spread to the liver – this is called secondary liver cancer. Your doctor may use the term ‘liver metastasis’ (which is another way of saying that cancer has spread to the liver). It is possible for there to be several cancer deposits (metastases) in the liver.
There is more than one sort of primary liver cancer. One such type starts within the cells which make up most of the liver tissue – this is known as a hepatoma, or sometimes hepatocellular carcinoma (HCC for short).
Another type begins in the cells which line the tubes (or ducts) that carry the bile out of the liver – this bile duct cancer is known as a cholangiocarcinoma. Hepatomas usually occur in people who have an underlying liver disease, such as scarring of the liver (also known as cirrhosis) and can be a long-term result of chronic hepatitis. There is no association between cirrhosis and the development of cholangiocarcinoma.
However, in the UK, secondary liver cancer is about 30 times more common than these primary liver cancers. Secondary cancer occurs in people who have a primary cancer which has begun elsewhere. The usual sites in the body where primary tumours develop before spreading to the liver include the lung, breast, large bowel,
stomach and pancreas. Cancer cells usually spread to the liver from the primary tumour through the bloodstream.
Other, much less common, types of cancers can occur in the liver. These grow at different speeds. Your doctor will explain if you have one of these sorts of tumour.
Tuesday, March 3, 2009
Treatment of liver cancer
The treatment options are dictated by the stage of liver cancer and the overall condition of the patient. The only proven cure for liver cancer is liver transplantation for a solitary, small (<3cm) tumor. Now, many physicians may dispute this statement. They may argue that a small tumor can be surgically removed (partial hepatic resection) without the need for a liver transplantation. Moreover, they may claim that the one and three year survival rates for resection are perhaps comparable to those for liver transplantation.
The results of the various medical treatments (chemotherapy, chemoembolization, ablation, and proton beam therapy) remain disappointing. Moreover, for reasons noted earlier (primarily the variability in natural history), there have been no systematic study comparisons of the different treatments. As a result, individual patients will find that the various treatment options available to them depend largely on the local expertise.
How do we know if a particular treatment worked for a particular patient? Well, hopefully, the patient will feel better. However, a clinical response to treatment is usually defined more objectively. Thus, a response is defined as a decrease in the size of the tumor on imaging studies along with a reduction of the alpha-fetoprotein in the blood, if the level was elevated prior to treatment.
Symptoms of liver
Symptoms of liver
The initial symptoms (the clinical presentations) of liver cancer are variable. In countries where liver cancer is very common, the cancer generally is discovered at a very advanced stage of disease for several reasons. For one thing, areas where there is a high frequency of liver cancer are generally developing countries where access to healthcare is limited. For another, screening examinations for patients at risk for developing liver cancer are not available in these areas. In addition, patients from these regions actually have more aggressive liver cancer disease. In other words, the tumor usually reaches an advanced stage and causes symptoms more rapidly. In contrast, patients in areas of low liver cancer frequency tend to have liver cancer tumors that progress more slowly and, therefore, remain without symptoms longer.In advanced liver cancer, the tumor can spread locally to neighboring tissues or, through the blood vessels, to elsewhere in the body (distant metastasis). Locally, liver cancer can invade the veins that drain the liver (hepatic veins). The tumor can then block these veins, which results in congestion of the liver. The congestion occurs because the blocked veins cannot drain the blood out of the liver. (Normally, the blood in the hepatic veins leaving the liver flows through the inferior vena ceva which is the largest vein that drains into the heart.) In African patients, the tumor frequently blocks the inferior vena cava. Blockage of either the hepatic veins or the inferior vena cava results in a very swollen liver and massive formation of ascites. In some patients, as previously mentioned, the tumor can invade the portal vein and lead to the rupture of esophageal varices.
On physical examination, an enlarged, sometimes tender, liver is the most common finding. Liver cancers are very vascular (containing many blood vessels) tumors. Thus, increased amounts of blood feed into the hepatic artery (artery to the liver) and cause turbulent blood flow in the artery. The turbulence results in a distinct sound in the liver (hepatic bruit) that can be heard with a stethoscope in about one quarter to one half of patients with liver cancer. Any sign of advanced liver disease (for example, ascites, jaundice, or muscle wasting) means a poor prognosis. Rarely, a patient with liver cancer can become suddenly jaundiced when the tumor erodes into the bile duct. The jaundice occurs in this situation because both sloughing of the tumor into the duct and bleeding that clots in the duct can block the duct.
Regarding the distant metastases, liver cancer frequently spreads to the lungs, presumably by way of the blood stream. Usually, patients do not have symptoms from the lung metastases, which are diagnosed by radiologic (x-ray) studies. Rarely, in very advanced cases, liver cancer can spread to the bone or brain.