Bone cancer

Bones do far more than hold us up. A typical healthy adult has over 200 bones, which:

• support and protect the internal organs
• are attached to muscles to allow movement
• contain bone marrow, which produces and stores new blood cells
• store protein, minerals and nutrients such as calcium

Bone cancer can develop as either a primary cancer, meaning the cancer started in the bone, or a secondary cancer, meaning it started somewhere else in the body and spread to the bone.

Primary and secondary bone cancer#

Primary bone cancer, also known as bone sarcoma, is rare. It affects people of all ages but is most often seen in people aged 10 to 25 years and in those over 50.

Secondary bone cancer is much more common than primary bone cancer, and it is more common in adults than in children. The bones are one of the most common sites that cancer spreads to.

Signs and symptoms#

The most common symptom of both primary and secondary bone cancer is strong pain in the affected bone or joint. The pain gradually becomes constant and does not improve with mild pain relievers such as paracetamol. It may be worse at night or during activity.

Other symptoms can include:

• swelling over the affected part of the bone
• stiffness or tenderness in the bone
• problems with moving around, such as an unexplained limp
• loss of feeling in the affected limb
• an unexplained fractured bone
• unexplained weight loss
• tiredness
• low levels of blood cells
• high calcium levels in the blood (hypercalcaemia)
• pressure on the nerves in the spine (spinal cord compression)

Not everyone with these symptoms has bone cancer, but if you have any of them or are worried, always see your doctor.

Risk factors#

The causes of most bone cancers are unknown, but some things can make primary bone cancer more likely. These risk factors include:

• Previous radiation therapy – radiation therapy used to treat cancer increases the risk of developing primary bone cancer. The risk is higher for people who have high doses at a young age, though most people who have radiation therapy will not develop bone cancer.
• Other bone conditions – such as Paget’s disease of the bone. Some studies also suggest people who have had a soft tissue sarcoma have an increased risk.
• Genetic factors – some inherited conditions, such as Li-Fraumeni syndrome, increase the risk, and people with a strong family history of certain cancers are also at higher risk.

Most bone cancers are not hereditary. Some people develop bone cancer because of genetic changes that happen during their lifetime, rather than inheriting a faulty gene. Having these risk factors does not mean you will develop bone cancer, and often there is no clear reason for it. If you are worried about your risk, ask your doctor for advice.

Secondary bone cancer is always caused by cancer cells spreading to the bone from elsewhere in the body. It is not fully understood why some people develop it and others do not.

Tests#

Your doctor may do some tests to check for primary or secondary bone cancer, including:

• blood tests – to check your general health
• x-ray – a two-dimensional picture of the inside of the body that can reveal bone damage or new bone growth
• bone scan – a small amount of radioactive dye is injected into a vein and a scan then shows any abnormal changes in the bones
• computed tomography (CT) scan – uses x-rays to take a three-dimensional picture of the inside of the body
• magnetic resonance imaging (MRI) scan – uses magnetism and radio waves to take pictures of the inside of the body
• positron emission tomography (PET) scan – a small amount of radioactive glucose solution is injected into a vein, and cancerous areas show up highlighted on the scan
• bone biopsy – some cells and tissue are removed from the affected bone for examination under a microscope

Types of primary bone cancer#

There are more than 30 types of primary bone cancer. The most common are:

• Osteosarcoma (about 35% of bone cancers) – starts in the cells that grow bone tissue. It usually affects the arms, legs and pelvis but can occur in any bone, and tends to affect children and young adults with growing bones, as well as older people in their 70s and 80s. Most are high-grade tumors.
• Chondrosarcoma (about 30% of bone cancers) – starts in the cells that grow cartilage. It usually affects the upper arms and legs, pelvis, ribs and shoulder blade, and most often occurs in middle-aged and older people. It is slow-growing, rarely spreads, and most are low-grade tumors.
• Ewing’s sarcoma (about 14% of bone cancers) – affects cells in the bone or soft tissue and is often associated with a large lump. It usually affects the pelvis, legs, ribs, spine and upper arms, is more common in children and young adults, and the tumors are high-grade.

Types of secondary bone cancer#

Any type of cancer can spread to the bone, causing secondary bone cancer. There are two main types:

• Osteolytic – bone is broken down without new bone being made. In some cases, holes called lytic lesions form, which can weaken the bone and increase the risk of breakage.
• Osteoblastic – new bone is formed but grows abnormally. These osteoblastic lesions are very hard and dense, but they make the bone weak and deformed.

Most people with secondary bone cancer develop either osteolytic or osteoblastic changes, but some have both.

Stages and grades#

The grade of the cancer describes how quickly it might grow. In general, the lower the grade, the better the prognosis, and knowing the grade helps your healthcare team plan the most suitable treatment.

• Low grade – the cancer cells look similar to normal cells. They are usually slow-growing and less likely to spread.
• High grade – the cancer cells look very different from normal cells. They grow quickly and are more likely to spread.

Many cancers are staged using a system that divides them into four stages, but bone cancer is different. Primary bone cancer is usually divided into:

• Localized – the cancer is found only in the bone where it started. It may be able to be removed by surgery (resectable) or not completely removed (non-resectable).
• Advanced (metastatic) – the cancer has spread to other parts of the body, such as the lungs.

Secondary bone cancer is when cancer cells have spread to the bones from another part of the body. Because it has already spread from its original location, doctors classify secondary bone cancer as advanced, or stage 4. Ask your doctor or nurse to explain the stage of your cancer.

Prognosis#

When someone is diagnosed with bone cancer, their doctor will give them a prognosis – an opinion of how likely the cancer is to spread and the chances of recovery. A prognosis depends on the type and stage of the cancer, as well as the person’s age and general health. Your doctor will talk to you about your individual situation. Every person’s experience is different, and there is support available to you.

Treatment for primary bone cancer#

Treatment for primary bone cancer depends on the type, the location and size of the tumor, whether the cancer has spread, and your age, fitness, general health and preferences. It usually includes surgery, chemotherapy, radiation therapy, or a combination of these.

Surgery#

There are different types of surgery depending on where the cancer is. People with cancer in a limb may have:

• Limb-sparing surgery – to remove the cancer but save the limb. The surgeon removes the affected part of the bone, and sometimes surrounding bone and muscle, to remove as much cancer as possible and reduce the chance of it coming back. The removed bone is replaced with a metal implant or a bone graft.
• Surgery to remove the limb (amputation) – in some cases it is not possible to remove all the cancer without affecting the limb too much, so the limb is removed. After the area has healed, you may be fitted with an artificial limb. This is less common now, applying to about 1 in 10 people.

People with bone cancer in other parts of the body may have surgery to remove the affected part of the bone where possible.

Chemotherapy#

Chemotherapy uses drugs to destroy or slow the growth of cancer cells while causing the least possible damage to healthy cells. It may be given for high-grade osteosarcoma and Ewing’s sarcoma – before surgery to shrink the tumor, after surgery or radiation therapy to kill any remaining cancer cells, or as palliative treatment to slow an advanced cancer or control symptoms.

Radiation therapy#

Radiation therapy (also known as radiotherapy) uses a controlled dose of radiation, such as focused x-ray beams, to kill or damage cancer cells. It may be used for Ewing’s sarcoma – after surgery or chemotherapy to kill remaining cancer cells, to help control the cancer if the tumor cannot be removed surgically, or as palliative treatment to control symptoms.

Treatment for secondary bone cancer#

The aim of treatment for secondary bone cancer is to control or shrink the cancer and relieve symptoms. This is called palliative treatment and may help you feel better. Options include:

• Hormone therapy – used for breast or prostate cancer that has spread to the bone. It lowers hormone levels or stops hormones reaching cancer cells, starving cancer cells that need hormones to grow.
• Chemotherapy – uses drugs to kill or slow the growth of cancer cells.
• Targeted therapy – uses drugs that attack specific parts of cancer cells to stop the cancer growing and spreading. Only some cancers can be treated this way, and the drugs used depend on the primary cancer.
• Immunotherapy – uses the body’s own immune system to attack the cancer. Several immunotherapy drugs are approved for lung and kidney cancer that has spread to the bones, and clinical trials are testing them for other cancers.
• Radiation therapy – uses a controlled dose of radiation to kill or damage cancer cells.

Treating bone damage#

Cancer can weaken a bone and cause fractures. Surgery to insert metal rods, plates, screws, wires, nails or pins can help strengthen a bone. Surgery may also be used if the cancer is pressing on the spinal cord and causing signs of damage.

If the cancer is causing severe back pain and damage to the bones in the spine, you may have an injection of bone cement into the bones to stabilize and strengthen them and relieve pain. This is called vertebroplasty.

Your doctor may also prescribe medicines to help strengthen your bones, reduce bone pain and control high calcium levels in the blood. There are two options for bone-strengthening drug treatment:

• bisphosphonates – given as an injection into a vein (intravenously) or as a tablet (orally)
• denosumab – given as an injection into the skin (subcutaneously)

Side effects of treatment#

All cancer treatments can have side effects. Your treatment team will discuss these with you before you start. Talk to your doctor or nurse about any side effects you are experiencing – some can be upsetting and difficult, but there is help if you need it.

Living with advanced cancer#

Advanced cancer usually means cancer that is unlikely to be cured. Some people can live for many months or years with advanced cancer, and during this time palliative care services can help.

Most people continue to have treatment for advanced cancer as part of palliative care, as it helps manage the cancer and improve day-to-day life. Many people think palliative care is only for those who are dying, but it is for any stage of advanced cancer, and there are doctors, nurses and others who specialize in it.

Treatment may include chemotherapy, radiation therapy or another approach, and it can help you live more comfortably by managing symptoms such as pain. Treatment depends on your preferences and what you want to do. Ask your doctor about treatment and palliative care services that may help you.

Caring for someone with cancer can be difficult at times. If you are caring for someone with bone cancer, support services are available for carers, family and friends.

Key points#

• Primary bone cancer, also known as bone sarcoma, is rare.
• The bones are one of the most common sites that cancer spreads to.
• The most common symptom of primary and secondary bone cancer is strong pain in the affected bone or joint.
• Other symptoms can include swelling, fractures, tiredness and low levels of blood cells.
• Treatment depends on the type and stage of cancer, and your doctor will work out a plan for your individual situation.

Where to get help#