Why Cancer Strikes Some

It's a conundrum that puzzles doctors and patients alike: one person smokes a few cigarettes per week in college and contracts lung cancer in middle age, while another person smokes a pack a day his whole life -- and lives to age 90.

A new program announced last week by the National Institutes of Health aims to unravel such mysteries by precisely measuring the role that environmental agents, such as pesticides and solvents, play in common diseases, including cancer, asthma, and autism.

A major part of the program will fund the development of technologies to monitor personal environmental exposures and to determine how those exposures interact with an individual's genetic makeup to increase the risk for disease. Scientists hope these technologies will allow doctors to determine who is at risk early on, and thus be able to intervene soon enough to prevent serious damage.

The NIH has designated $88 million for the period 2007-10 to fund research both inside and outside the institute. The money will go toward development of wearable sensors that measure exposure to environmental toxins, such as solvents, pesticides, and heavy metals.

The funds will also support the development of sensors to determine if exposure to toxins triggers biochemical pathways linked to disease, such as inflammation or cell death, in some individuals. Ultimately, these technologies will be incorporated into genetic studies to understand the link between genes, the environment, and disease.

Initially, the sensors would be used in population studies of disease. But David Schwartz, director of the National Institute of Environmental Health Sciences (part of the NIH), envisions a day when everyone would wear a sensor that measured levels of key chemicals. An individual's doctor could then read the information and determine if the patient had been exposed to chemicals and therefore was at risk of developing a disease.

The role of environmental toxins in human disease and death has been a major issue in both the public health and legal arenas. Scientists often have difficulty determining if a reported increase in disease, such as a cancer cluster, is linked to a specific factor in the environment. Emerging technologies that could accurately measure exposure and individual response to different chemicals could clarify these often contentious cases.

New technologies could also help scientists understand some medical mysteries of our time -- such as rising asthma rates, which have doubled in the last two decades. Since the publication of the human genome sequence in 2003, scientists have focused enormous amounts of energy on the genetic basis of disease. "But genes don't tell the whole story," says Schwartz. "The recent increases in asthma, diabetes, and autism are not due to changes in our genome over last couple of decades. These major shifts point to the role our diet, activity levels, and environment play in disease."

"Scientists can now precisely measure genetic variation between individuals, but we can't accurately measure the individual variation in exposure or response to exposure...when faced with environmental challenges," Schwartz says. The new program hopes to fill that gap.

This timely program will take advantage of the explosion of information about the genome sequence, says Gerald N. Wogan, professor of chemistry and biological engineering at MIT. For example, scientists already know that people carry different forms of enzymes that detoxify chemicals, and that specific variants increase the risk of bladder cancer. But these new tools would allow scientists to do this kind of research on a much broader scale, he says.

Esteban González Burchard, a scientist at the University of California, San Francisco, believes that these kinds of tools will also help researchers understand complex diseases, such as asthma. His team, for instance, has shown that people with a particular genetic background are more likely to develop asthma when exposed to secondhand smoke. But the environmental contribution to asthma is probably even more complex, he says, with factors such as socioeconomic status also playing a role. And new technologies could help scientists sort out these complex factors.

Educate Yourself To Fight Against Mesothelioma

The use of asbestos had gained a new momentum in the twentieth century. You can speculate the wide range use of asbestos throughout the world just from the figure that states the amount of asbestos only used in the United States. The amount touches up to 30 million tons that have been used in different industrial sectors. It mainly comprises of the shipyards, construction of buildings, houses, hospitals and schools. The figure also gives an account of the rising numbers of victims suffering from the Mesothelioma cancer every year that have now reached 10000 and most of them are actually the workers in these industrial sectors those who have come in direct contact with the deadly mineral asbestos.

In the earlier times a misconception prevailed relating to this disease. Smoking cigarettes was considered to be the main cause but now there is no doubt in the fact that no other thing but asbestos can only damage the Mesothelium tissues in the body.

Things everyone must know about Mesothelioma:

* Asbestos is the main reason of Mesothelioma attack in the body.

* Asbestos fibers and dust enter the body through different channels but mainly through the air you breathe in.

* Asbestos fibers can readily mix with the atmosphere and form airborne particles and they strike directly on the Mesothelium lining protecting different internal organs in your body.

* The major organs that are at risk due to the Mesothelioma cancer are the heart, lungs, and abdominal cavity.

* Mesothelioma can happen in a person's body long after he has been in contact with the asbestos particles. The time limit ranges from 10-30 years.

* Life after the diagnosis is really short because Mesothelioma is mostly detected when the patient has already reached the final stage.

* The treatments that can help the patient to extend the life span are chemotherapy; radiation therapy and surgery but none of these traditional modes of treating cancer can give the ultimate solution to the patient.

* There are a few modern treatments devised with latest developments are helping the Mesothelioma patients to stay well. Among them the immunotherapy and the gene therapy have gained wide popularity.

* Mesothelioma can be fought for legal claims as well. So you must be aware of the legal prospects that can at least help you with a justified financial support to continue with the medical treatment and also a help for your family if you die. Mesothelioma attorneys are working to serve you for your benefits. Get help from them.

From A Great Guide : Mesothelioma Claims

"you can find origin of this entry at
www.mesotheliomaclaims.com (Mesothelioma Claims)"

What is mesothelioma?
Mesothelioma is caused by exposure to asbestos and symptoms may not appear for as long as 20 to 40 years after exposure. Mesothelioma is a cancerous tumor of the mesothelium. The mesothelium is the tissue made up of specialized cells called mesothelial cells which line the chest cavity, abdominal cavity, and the cavity around the heart. These cells also cover the outer surface of most internal organs.

The mesothelium produces a special lubricating fluid that allows organs to move around within the body with less friction. For example, this fluid makes it easier for the lungs to move inside the chest during breathing.

The mesothelium of the chest is known as the pleura. The mesothelium of the abdomen is called the peritoneum. The mesothelium of the pericardial cavity, which is the space around the heart, is called the pericardium.

Mesothelioma is a cancer that attacks any of these mesothelial regions.

What is the difference between mesothelioma and malignant mesothelioma?
Tumors of the mesothelium can either be benign or malignant. A benign tumor is non-cancerous. A malignant tumor is cancerous, and one occurring on the mesothelium is called malignant mesothelioma. Because most mesothelial tumors are cancerous, malignant mesothelioma is commonly referred to as simply mesothelioma, or in casual conversation meso.

What are the causes of mesothelioma?
Asbestos exposure is the primary cause of mesothelioma. After asbestos fibers are breathed in, they travel to the ends of small air passages and reach the pleura where they cause physical damage to mesothelial cells that may result in cancer. They also cause injury to lung cells that can result in lung cancer and/or asbestosis (replacement of lung tissue by scar tissue). If ingested, these fibers can travel to the abdominal cavity and cause peritoneal mesothelioma.

While exposure to asbestos is mostly occupational, it can also be environmental. Exposure to asbestos can also occur from being in close contact with an asbestos worker. For example, the work clothes of an asbestos worker can expose a family member to asbestos fibers while doing laundry.

What is asbestos? The main risk factor for developing mesothelioma is exposure to asbestos. The term asbestos refers to a family of magnesium-silicate mineral fibers. In the past, asbestos was used widely for insulation because it does not conduct heat well and is resistant to burning. As the link between asbestos and mesothelioma has become more well known, the use of this material has decreased. However, up to 8 million Americans may already have been exposed to asbestos. Although asbestos has not been used in construction since approximately 1975, the products already in place present a danger to individuals involved in repair work and the demolition of structures containing asbestos products.

It is possible that asbestos causes cancer by physically irritating cells rather than by a chemical effect. When asbestos fibers are inhaled, the long, thin fibers may reach the ends of the small airways and penetrate into the pleural lining of the lung and chest wall. These fibers may then directly injure mesothelial cells of the pleura, and eventually cause mesothelioma.

People exposed to asbestos at an early age, for a long period of time, are most likely to develop this cancer. Mesothelioma, however, takes a very long time to develop. The time between exposure and diagnosis of mesothelioma is usually between 20 and 40 years.

What are the symptoms of mesothelioma?
It is important to note that symptoms of mesothelioma may not appear until 30 to 50 years after exposure to asbestos. The early symptoms of malignant mesothelioma are common symptoms that are not specific to the disease itself. People often mistake the symptoms for everyday sicknesses and ailments such as the common cold. Many people with mesothelioma have symptoms for only a few months before they are diagnosed.

Over half of the patients with pleural mesothelioma have pain at the side of the chest or in the lower back. Shortness of breath is almost always a symptom shared by patients. Some report coughing, fever, sweating, fatigue, difficulty swallowing, and weight loss. Extreme symptoms include coughing up blood, swelling of the face and arms, muscle weakness, and sensory loss.

Symptoms of peritoneal mesothelioma include abdominal pain, weight loss, nausea, and vomiting. Some patients also suffer from hernias, fluid in the abdominal cavity, or the presence of a mass or bulge in the abdomen.

Anyone experiencing any of these symptoms who believes he or she has been exposed to asbestos should see a doctor immediately for diagnosis.

How is a person diagnosed with mesothelioma?
One reason why mesothelioma is such a dangerous form of cancer is because it is difficult to diagnose. Mesothelioma usually progresses to a dangerous stage by the time it is finally diagnosed. For these reasons it is incredibly important to see a doctor as soon as you experience any of the aforementioned symptoms.

It is essential that you give your doctor a complete medical history. Be sure to inform your doctor if you have been exposed to asbestos at work or through a family member. It is important to also tell your doctor when and for how long your exposure to asbestos occurred. Your medical history will help your doctor assess the risk factors associated with mesothelioma, as well as your symptoms.

A physical exam will provide your doctor with information about signs of mesothelioma and other health problems you may be experiencing. Patients with pleural mesothelioma often have fluid in their chest cavity, which is called pleural effusion. A physical exam can also detect the presence of ascites (fluid in the abdominal cavity) in patients with peritoneal mesothelioma. In patients with pericardial mesothelioma, pericardial effusion (fluid in the pericardium) can also be detected during a physical exam by a doctor.

After your medical history and physical exam, you should expect to undergo some medical tests. The tests performed by your doctor can range from basic imaging tests to tests of fluid and tissue samples.

The most basic test is a chest x-ray. The x-ray will show abnormalities involving the lungs, such as irregular thickening of the pleura, lowering of the space between the lungs, abnormal mineral deposits, and fluid build up inside of the lungs. A doctor will either take a CT scan (computed tomography scan) or an MRI (magnetic resonance imaging scan) to try and determine the location, size and mass of a possible cancerous growth. The CT scan uses a rotating x-ray beam to create a series of pictures of the body from many different angles. A computer then combines these pictures to produce cross-sectional images of a part of the body. A doctor may need to inject a dye into a vein in order to highlight details on the CT scan. An MRI uses magnetic fields instead of x-rays to create its images. After the magnetic fields capture the information, a computer generates a detailed cross-sectional image.

If pleural mesothelioma is suspected, the doctor may look inside the chest cavity with a special instrument called a thoracoscope. A peritoneoscope can be used in a similar procedure to look at the abdomen. In this procedure the doctor is looking for abnormal cell growths, which will usually be referred to as tumors. The thoracoscope (telescope-like instrument connected to a video camera) is inserted through a small incision in the chest. The doctor can see the tumor through the thoracoscope, and can use special forceps to take a tissue biopsy.

After looking at the piece of the tumor under a microscope, the doctor may decide whether the tumor is benign, which means that it is not cancerous, or malignant, which means that it is cancerous.

If the doctor can't tell from the biopsy if the growth is cancerous, there are several other options. The doctor may take a sample of any fluid that has built up around the lungs, stomach or heart, or he may take a blood sample to see if your blood cell levels are what they are supposed to be.

In patients with a pleural effusion, a sample of this fluid can be removed by inserting a needle into the chest cavity. The fluid is then tested and its chemical make-up is then viewed under a microscope to determine whether cancer cells are present. A similar technique can also be used to obtain abdominal fluid and pericardial fluid.

It is often difficult to simply diagnose mesothelioma by looking at the cells from the fluid around the lungs, abdomen or heart. It is even hard to accurately diagnose mesothelioma solely with tissue from biopsies. Mesothelioma can look like several other types of cancer under a microscope. Special laboratory tests are often done to help distinguish mesothelioma from some other types of cancer. These tests often use special techniques to recognize certain markers (various types of chemicals) known to be present in mesotheliomas.

What are the different types of mesothelioma?
About 75% of mesothelioma occurrences start in the chest cavity. This is known as pleural mesothelioma. Another 10% to 20% is peritoneal mesothelioma which begins in the abdomen. Pericardial mesothelioma, found in the cavity around the heart, is very rare.

Pleural Mesothelioma
Pleural mesothelioma spreads within the chest cavity, sometimes involving the lungs.

The onset of mesothelioma is usually very slow, the most common symptom is persistent pain localized in the chest. Sometimes the pain is accompanied by severe difficulty breathing, which is caused by an accumulation of fluid in the pleural space.

Peritoneal Mesothelioma
Peritoneal mesothelioma involves the abdominal cavity, infiltrating the liver, spleen or bowels. Due to fluid accumulation in the abdominal cavity (ascites), the abdomen appears enlarged. The patients experience nausea, vomiting, fever and difficulty in moving their bowels.

The prognosis is poorer for peritoneal mesothelioma with a median survival time of about 10 months from the onset of symptoms.

Rare Forms of Mesothelioma
Mesothelioma of the pericardium is a very seldom seen cardiac cancer. The mass is usually detected at a late stage and the prognosis is very poor, with or without therapy. Mesotheliomas of the ovaries and the scrotum have also been reported.

Benign Forms of Mesothelioma
A rare form of mesothelioma is the cystic mesothelioma of the peritoneum. Its prognosis is benign. Its occurrence has been discovered primarily in young women.

What are the stages of malignant mesothelioma?
Once a person has been diagnosed with malignant mesothelioma, more tests will have to be done in order to determine whether or not the cancer has spread to other parts of the body. This process is called staging. The stage of the cancer must be determined in order to plan treatment. The following stages are used to describle malignant mesothelioma:

Localized Malignant Mesothelioma

Stage 1: The cancer is present in the lining of the chest cavity near the lungs and heart or in the diaphragm of the lung.

Advanced Malignant Mesothelioma

Stage II: The cancer has spread beyond the lining of the chest to the lymph nodes of the chest. Lymph nodes are collections of immune system cells that help the body fight off infections.

Stage III: The cancer has spread through the diaphragm or abdominal lining and into the chest wall, center of the chest, the heart, or nearby lymph nodes.

Stage IV: The cancer has spread to distant organs or tissues.

Mesothelioma Guide : Signs and Symptoms

Symptoms of mesothelioma may not appear until 20 to 50 years after exposure to asbestos. Shortness of breath, cough, and pain in the chest due to an accumulation of fluid in the pleural space are often symptoms of pleural mesothelioma.

Symptoms of peritoneal mesothelioma include weight loss and cachexia, abdominal swelling and pain due to ascites (a buildup of fluid in the abdominal cavity). Other symptoms of peritoneal mesothelioma may include bowel obstruction, blood clotting abnormalities, anemia, and fever. If the cancer has spread beyond the mesothelium to other parts of the body, symptoms may include pain, trouble swallowing, or swelling of the neck or face.

These symptoms may be caused by mesothelioma or by other, less serious conditions.

Mesothelioma that affects the pleura can cause these signs and symptoms:

chest wall pain
pleural effusion, or fluid surrounding the lung
shortness of breath
fatigue or anemia
wheezing, hoarseness, or cough
blood in the sputum (fluid) coughed up (hemoptysis)
In severe cases, the person may have many tumor masses. The individual may develop a pneumothorax, or collapse of the lung. The disease may metastasize, or spread, to other parts of the body.

Tumors that affect the abdominal cavity often do not cause symptoms until they are at a late stage. Symptoms include:

abdominal pain
ascites, or an abnormal buildup of fluid in the abdomen
a mass in the abdomen
problems with bowel function
weight loss
In severe cases of the disease, the following signs and symptoms may be present:

blood clots in the veins, which may cause thrombophlebitis
disseminated intravascular coagulation, a disorder causing severe bleeding in many body organs
jaundice, or yellowing of the eyes and skin
low blood sugar level
pleural effusion
pulmonary emboli, or blood clots in the arteries of the lungs
severe ascites
A mesothelioma does not usually spread to the bone, brain, or adrenal glands. Pleural tumors are usually found only on one side of the lungs.

Mesothelioma Guide : What is Mesothelioma?

Mesothelioma is a form of cancer that is almost always caused by previous exposure to asbestos. In this disease, malignant cells develop in the mesothelium, a protective lining that covers most of the body's internal organs. Its most common site is the pleura (outer lining of the lungs and internal chest wall), but it may also occur in the peritoneum (the lining of the abdominal cavity),the heart, the pericardium (a sac that surrounds the heart) or tunica vaginalis.

Most people who develop mesothelioma have worked on jobs where they inhaled asbestos particles, or they have been exposed to asbestos dust and fiber in other ways. Washing the clothes of a family member who worked with asbestos can also put a person at risk for developing mesothelioma.Unlike lung cancer, there is no association between mesothelioma and smoking, but smoking greatly increases risk of other asbestos induced cancer.Compensation via asbestos funds or lawsuits is an important issue in mesothelioma (see asbestos and the law).

The symptoms of mesothelioma include shortness of breath due to pleural effusion (fluid between the lung and the chest wall) or chest wall pain, and general symptoms such as weight loss. The diagnosis may be suspected with chest X-ray and CT scan, and is confirmed with a biopsy (tissue sample) and microscopic examination. A thoracoscopy (inserting a tube with a camera into the chest) can be used to take biopsies. It allows the introduction of substances such as talc to obliterate the pleural space (called pleurodesis), which prevents more fluid from accumulating and pressing on the lung. Despite treatment with chemotherapy, radiation therapy or sometimes surgery, the disease carries a poor prognosis. Research about screening tests for the early detection of mesothelioma is ongoing.

Detailed Guide: What Is Bone Cancer?

Normal bone tissue

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.

Bone itself is very hard and strong. Some bone is able to support as much as 12,000 pounds per square inch. It takes as much as 1,200 to 1,800 pounds of pressure to break the femur (thigh bone). The outside of the bone is covered with a layer of fibrous tissue called periosteum. The bone itself contains 2 kinds of cells. The osteoblast is the cell that lays down new bone, and the osteoclast is the cell that dissolves old bone. Although bone often looks like it doesn't change much, the truth is that it is very active. Throughout our bodies, new bone is always forming while old bone is dissolving.

Inside hollow bones is a space called the medullary cavity where bone marrow is found. In some bones the marrow is only fatty tissue. The marrow in other bones is a mixture of fat cells and blood-forming cells. The blood-forming cells produce red blood cells, white blood cells, and blood platelets. Other cells in the marrow include plasma cells, fibroblasts, and reticuloendothelial cells.

Cells from any of these tissues can develop into a cancer.

Types of bone cancers

Most of the time when someone with cancer is told they have cancer in the bones, the doctor is talking about a cancer that spread there from somewhere else. This is called metastatic cancer. It can be seen in many different types of advanced cancer, such as breast cancer, prostate cancer, and lung cancer. When these cancers in the bone are looked at under a microscope, they resemble the tissue they came from. For example, if someone has lung cancer that has spread to bone, the cells of the cancer in the bone still look and act like lung cancer cells. They do not look or act like bone cancer cells, even though they are in the bones. Since these cancer cells still act like lung cancer cells, they still need to be treated with drugs that are used for lung cancer. For more information about metastatic bone cancer, please see the American Cancer Society document Bone Metastases, as well as the document on the specific place where the cancer started (Breast Cancer, Lung Cancer, Prostate Cancer, etc.).

Other kinds of cancers that are sometimes called "bone cancers" start in the blood forming cells of the bone marrow -- not in the bone itself. The most common bone cancer is called multiple myeloma. Another cancer that starts in the bone marrow is leukemia, although it is generally considered a "blood cancer" rather than a "bone cancer." Sometimes, lymphomas, which more often start in lymph nodes, can start in bone marrow. Multiple myeloma, lymphoma, and leukemia are not discussed in this document. For more information on these cancers, refer to the individual document for each.

A primary bone tumor is a tumor that starts in the bone itself. The main type of cancers that are true (or primary) "bone" cancers are called sarcomas. This is a term that describes the type of tissue that the cancer started in. Sarcomas are cancers that start in bone, muscle, fibrous tissue, blood vessels, fat tissue, as well as some other tissues. They can develop anywhere in the body.

There are several different types of bone tumors. Their names are based on the area of bone or surrounding tissue that is affected and the kind of cells forming the tumor. Some primary bone tumors are benign (not cancerous), and others are malignant (cancerous). Most bone cancers are called sarcomas.

Benign bone tumors

Benign tumors do not spread to other tissues and organs and so are not usually life threatening. They are generally cured by surgery. Types of benign bone tumors include:

osteoid osteoma
osteoblastoma
osteochondroma
enchondroma
chondromyxoid fibroma.
These benign tumors are not discussed further in this document, which is limited to bone cancers.

Malignant bone tumors

Osteosarcoma: Osteosarcoma (also called osteogenic sarcoma) is the most common primary bone cancer. This cancer starts in the bone cells. It most often occurs in young people between the age of 10 and 30, but about 10% of osteosarcoma cases develop in people in their 60s and 70s. It is rare during middle age, and is more common in males than females. These tumors develop most often in bones of the arms, legs, or pelvis. For more information, see the American Cancer Society document, Osteosarcoma.

Chondrosarcoma: Chondrosarcoma is a cancer of cartilage cells. It is the second most common primary bone cancer. This cancer is rare in people younger than 20. After age 20, the risk of getting a chondrosarcoma goes up until about age 75. Women get this cancer as often as men.

Chondrosarcomas can develop in any place where there is cartilage. Most develop in bones such as the pelvis, leg bone or arm bone. Occasionally, chondrosarcoma will develop in the trachea, larynx, and chest wall. Other sites are the scapula (shoulder blade), ribs, or skull.

Benign (non-cancerous) tumors of cartilage are more common than malignant ones. These are called enchondromas. Another type of benign tumor that has cartilage is a bony projection capped by cartilage called an osteochondroma. These benign tumors rarely turn into cancer. There is a slightly higher chance of cancer developing in people who have many of these tumors, but this is still not common.

Chondrosarcomas are classified by grade, which measures how fast they grow. The grade is assigned by the pathologist (a doctor specially trained to examine and diagnose tissue samples under a microscope) after looking at the tumor under the microscope. The lower the grade, the slower the cancer grows. When a cancer is slow growing, the chance that it will spread is lower and so the outlook is better. Most chondrosarcomas are either low grade (grade I) or intermediate grade (grade II). High grade (grade III) chondrosarcomas, which are the most likely to spread, are less common.

Some chondrosarcomas have distinctive features under a microscope. These variants of chondrosarcoma can have a different prognosis (outlook) than usual chondrosarcomas.

Dedifferentiated chondrosacromas start out as typical chondrosarcomas but then some parts of the tumor change into cells like those of an osteosarcoma or fibrosarcoma. This variant of chondrosarcoma tends to occur in older patients and is more aggressive than usual chondrosarcomas.
Clear cell chondrosarcoma is a rare variant that grows slowly. It rarely spreads to other parts of the body unless it has already come back several times in the original location.
Mesenchymal chondrosarcomas can grow rapidly, but like Ewing tumor, are sensitive to treatment with radiation and chemotherapy.
Ewing tumor: Ewing tumor is the third most common primary bone cancer. This cancer (also called Ewing sarcoma) is named after the doctor who first described it in 1921, Dr. James Ewing. Most Ewing tumors develop in bones, but they can start in other tissues and organs. The most common sites for this cancer are the pelvis, the chest wall (such as the ribs or shoulder blades), and the long bones of the legs or arms. This cancer is most common in children and teenagers and is rare in adults over age 30. Ewing tumors occur most often in white people and are rare among African Americans and Asian Americans. More detailed information about this cancer can be found in the American Cancer Society document, Ewing Family of Tumors.

Malignant fibrous histiocytoma: Malignant fibrous histiocytoma (MFH) more often starts in "soft tissue" (connective tissue such as ligaments, tendons, fat, and muscle) than in bones. When MFH occurs in bones, it usually affects the legs (often around the knees) or arms. This cancer most often occurs in elderly and middle-aged adults and is rare among children. MFH tends to grow quickly and often spreads to other parts of the body, like the lungs and lymph nodes. MFH mostly tends to grow locally, but it can spread to distant sites

Fibrosarcoma: This is another type of cancer that develops more often in "soft tissues" than it does from bones. Fibrosarcoma usually occurs in elderly and middle-aged adults. Leg, arm, and jaw bones are the ones most often affected.

Giant cell tumor of bone: This type of primary bone tumor has benign and malignant forms. The benign (non-cancerous) form is most common. Giant cell bone tumors typically affect the leg (usually, near the knees) or arm bones of young and middle-aged adults. They don't often spread to distant sites, but tend to come back where they started after surgery (this is called local recurrence). This can happen several times. With each recurrence, the tumor becomes more likely to spread to other parts of the body. Rarely, a giant cell bone tumor spreads to other parts of the body without first recurring locally. This happens in the malignant (cancer) form of the tumor.

Chordoma: This primary tumor of bone usually occurs in the base of the skull and bones of the spine. It develops most often in adults older than 30 years, and is about twice as common in men than in women. Chordomas tend to grow slowly and often do not spread to other parts of the body, but they often come back in the same area if they are not removed completely. When they do spread, lymph nodes, the lungs, and the liver are the most common areas for secondary tumors.

Other cancers that develop in bones

Non-Hodgkin lymphoma

Non-Hodgkin lymphoma generally develops in lymph nodes but sometimes starts in the bone. Primary non-Hodgkin lymphoma of the bone is often a widespread disease because multiple sites in the body are usually involved. The outlook is similar to other non-Hodgkin lymphomas of the same subtype and stage. Primary lymphoma of the bone is given the same treatment as lymphomas that start in lymph nodes -- it is not treated like a primary bone sarcoma. For more information see the American Cancer Society document, Non-Hodgkin Lymphoma.

Multiple myeloma

Multiple myeloma is almost always found in bones, but doctors do not consider it a bone cancer because it develops from the plasma cells of the bone marrow (the soft inner part of some bones). Although it causes bone destruction, it is no more a bone cancer than is leukemia. It is treated as a widespread disease. At times, myeloma can be first found as a single tumor (called a plasmacytoma) in a single bone, but most of the time it will go on to spread to the marrow of other bones. For more information see the American Cancer Society document, Multiple Myeloma.

Last Revised: 07/02/2008

Detailed Guide: What Is Cancer?

Cancer begins when cells in a part of the body start to grow out of control. There are many kinds of cancer, but they all start because of out-of-control growth of abnormal cells.

How a normal cell becomes cancer

Normal body cells grow, divide, and die in an orderly fashion. During the early years of a person's life, normal cells divide faster to allow the person to grow. After the person becomes an adult, most cells divide only to replace worn-out or dying cells or to repair injuries.

Because cancer cells continue to grow and divide, they are different from normal cells. Instead of dying, cancer cells outlive normal cells and keep forming new abnormal cells. Another difference between cancer cells and normal cells is that cancer cells can invade (grow into) other tissues. Being able to grow out of control and to invade other tissues makes a cell a cancer cell.

Cells become cancer cells because of damage to DNA. DNA is in every cell and directs all its actions. Most of the time, when DNA gets damaged the cell can fix it. If the cell can’t repair the damage, the cell dies. In cancer cells the damaged DNA is not repaired, but the cell doesn’t die like it should. Instead, this cell goes on making new cells even though the body does not need them. These new cells will all have the same DNA damage as the first cell does.

People can inherit damaged DNA, but most of the time DNA damage is caused by something we are exposed to in our environment. Sometimes the cause of the DNA damage is something obvious, like cigarette smoking. But many times no clear cause is found.

A cancer cell has many mistakes in its DNA -- having damage in just one spot does not cause cancer. Even when someone inherits damaged DNA, more mistakes in their DNA are needed before a cancer will develop. Staying away from things that are known to damage DNA (like smoking) as a part of a healthy life style lowers the chance that more DNA damage will take place. This can reduce the risk of cancer -- even in people who have an inherited tendency to get cancer.

How cancers grow and spread

In most cases the cancer cells form a tumor. Some cancers, like leukemia, do not form tumors. Instead, these cancer cells involve the blood and blood-forming organs and circulate through other tissues where they grow. But sometimes the extra cells in these blood cancers may also form a mass of tissue called a tumor.

Cancer cells often travel to other parts of the body, where they begin to grow and replace normal tissue. This process is called metastasis. It happens when the cancer cells get into the bloodstream or lymph vessels of our body.

But no matter where a cancer may spread, it is always named for the place where it started. For example, breast cancer that has spread to the liver is still called breast cancer, not liver cancer. Prostate cancer that has spread to the bone is metastatic prostate cancer, not bone cancer.

Not all tumors are cancerous. Tumors that aren't cancer are called benign. Benign tumors can cause problems -- they can grow very large and press on healthy organs and tissues. But they cannot grow into (invade) other tissues. Because they can't invade, they also can't spread to other parts of the body (metastasize). These tumors are almost never life threatening.

How cancers differ

Different types of cancer can behave very differently. For example, lung cancer and breast cancer are very different diseases. They grow at different rates and respond to different treatments. That is why people with cancer need treatment that is aimed at their particular kind of cancer.

How common is cancer

Cancer is the second leading cause of death in the United States. Nearly half of all men and a little over one third of all women in the United States will develop cancer during their lifetimes.

Today, millions of people are living with cancer or have had cancer. The risk of developing most types of cancer can be reduced by changes in a person's lifestyle, for example, by quitting smoking and eating a better diet. Often, the sooner a cancer is found and treatment begins, the better are the chances for living for many years.

Last Medical Review: 02/24/2009
Last Revised: 02/24/2009