What does it do?

For example, a tumour on the pancreas can grow to block the bile duct, leading to the patient developing obstructive jaundice. And a brain tumour can push on important parts of the brain, causing blackouts, fits and other problems. Even benign tumours can cause these problems if located in the wrong place. When a cancer invades nearby tissues, it can cause bleeding from damaged blood vessels, and stop the organ which it is are invading from working properly.

What happens if it spreads?

As a tumour grows, cells can break off and start growing on adjacent tissues and organs. For example, if bowel cancer has spread through the wall of the bowel itself, it can start growing on the bladder. Cells can also enter the bloodstream and travel to distant organs, such as the lungs or brain. The technical term for this is ’metastasis’.

When new tumours form on distant organs, they behave like the original tumour - so a bowel cancer cell growing in the lung will not be lung cancer. Once other organs are involved, then any symptoms of the cancer can get worse. However, it may be some time before a growing cancer in certain parts of the body produces symptoms that the patient can notice.

Once a cancer has started to spread beyond its original site, then the chances of a cure often begin to fall, as it becomes more difficult to treat.

How is it treated?

There are three principal ways of treating cancer. The first is surgery, normally an operation to remove the cancerous growth, and (depending on its type) nearby tissues and organs. A cancer patient may first undergo a minor operation called a biopsy to take a small sample of the cancer for analysis. The surgeon will try to remove as much of the cancer as possible, but sometimes extra treatment will be needed. This could either take the form of radiotherapy or chemotherapy, or a combination of treatments.

What is the outlook?

While the overall number of new cancers is not falling, the good news is that successful treatment rates for many of the most common types are improving rapidly

Support

All patients treated with chemotherapy will be looked after by a team of healthcare professionals, who are there to support you and access specialist support if required.

Introduction - Bone cancer

Primary bone cancer, where the tumour actually develops from bone cells, is very rare - about 500 cases are diagnosed in the UK each year (only about one in every 500 cancers).

There are several different types, depending on the type of bone cells involved:

• • Osteosarcoma (the most common) which often affects the large bones of the leg or the upper arm

  • Chondrosarcoma, formed from the cells which normally produce cartilage

  • Ewing’s sarcoma, usually in the pelvis, thigh or shin

  • Spindle cell sarcoma

Causes

Unlike most cancers, bone cancer tends to affect the young. Osteosarcoma usually appears in children and young adults, while Ewing’s sarcoma is most common between the ages of 10 and 20.

Other risk factors include:

• • Previous radiotherapy treatment, especially at a young age. Some chemotherapy drugs also increase the risk of osteosarcoma.

  • As many as one in eight people who develop a tumour of the eye will go on to develop an osteosarcoma, possibly because of a genetic susceptibility to both conditions, and the additional effect of anti-cancer treatments.

  • Genetic conditions linked to bone tumours including Li-Fraumeni syndrome, HME, inherited breast cancer andcongenital umbilical hernia (Ewing’s sarcoma is three times more common in children with this condition).

  • Paget’s disease, a bone disease which generally occurs in older people and increases the risk of osteosarcoma, as does another bone condition called chondroma.

  • Bone cancer has often been linked to injuries to a limb but it’s questionable and may simply be that the injury draws attention to a tumour that was already growing.

Many primary cancers can spread to bones, in particular breast,prostate, lung, thyroid and kidney cancer. Because the cancer is formed from the primary cells, such as breast or lung cells, it has to be treated with drugs, radiotherapy or other treatments that would usually be used to target the primary cancer. If you’re affected by secondary bone cancer, always check information on the primary cancer first.

Symptoms

The symptoms of bone cancer depend where the tumour grows (about half occur in or near the knee). By the time a lump or swelling is detectable, the cancer may have been present for some time. Pain, especially at night, is a common problem and may cause a limp if the leg is affected, because weight-bearing is uncomfortable or the cancer interferes with the way the joints work.

There may also be generalised symptoms such as weight loss, sweats, fever and lethargy or tiredness. Sometimes bone cancer is discovered incidentally – when an x-ray is taken after an accident for example – or occasionally when the bone breaks due to weakness caused by the cancer.

Diagnosis

X-rays which suggest cancer may show areas of bone destruction, new bone growth, swelling and changes in the surrounding soft tissues. Further tests may include a bone scan (involving the injection of a radioactive substance to show up the bones clearly), MRI and other scans.

Ultimately a biopsy is necessary to obtain sample of cells which can be studied under the microscope to check for cancer. Specialists usually carry out bone biopsies by placing a needle through the skin into the bone and drawing out some cells.

Treatment

Treatment will depend on an assessment of what type of cancer is present and how far it has spread – this is called staging, and involves a combination of the grade of the cancer (a measure of how abnormal the cells look under the microscope and therefore how aggressive) and whether it has spread either locally or to another organ in the body. Bone cancer which has not spread outside the bone may just be treated with surgery and not require chemotherapy. More abnormal bone cancer that has spread will be more difficult to treat, and chemotherapy as well as surgery is usually recommended.

In general, treatment of bone cancer has a good outlook, especially if it’s in the early stages and can be completed during surgery. About two thirds of people with primary bone cancer can be cured. But if the cancer is more advanced or has spread, the prognosis may not be so good, with five year survival rates of only 10-20 per cent. It’s vital that you talk to your specialist to get a picture of how successful treatment is likely to be in your individual case.

Treatment usually consists of surgery often combined with chemotherapy to shrink the tumour and make it less likely to recur. Because surgery involves removing bone, it can be quite drastic. Where possible the surgeon will try to replace the diseased bone with a graft of bone from elsewhere in the body or an implant, but sometimes amputation is necessary.

Some bone cancers, such as Ewing’s sarcoma, respond well to chemotherapy and other treatments such as radiotherapy. Newer “biological” therapies which are based on natural body chemicals such as Interferon, are also being used. These may work, for example, by encouraging the body's immune system to attack the cancer cells. A number of different research trials are currently looking at different combinations of these treatments in an effort to improve results.

After initial treatment, regular follow up is essential to check for recurrences and manage the consequences of treatment, such as the use of an artificial limb.

http://www.bbc.co.uk/health/physical_health/conditions/in_depth/cancer/

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