Bone Cancer: Types, Causes & Symptoms

Bone cancer is when cancer cells grow out of control in your bone. This can damage normal bone tissue. Metastasis may start in your bone or spread from other parts of your body.

Bone cancer is not common. Most bone tumors are benign. They are not cancerous and do not spread to other body parts. However, they may still weaken your bones and lead to broken bones or other problems.

Primary bone cancers are cancers that form in the bone itself. However, many tumors that begin in organs or other parts of the body can also spread to the bones. These tumors are known as secondary or metastatic bone cancers. They are caused by cancer cells spreading from the original tumor to other parts of the body. Treatment includes surgery and chemotherapy, depending on the type of cancer.

Causes

The root cause of bone cancer remains unknown, but researchers believe it occurs due to genetic mutations that trigger abnormal cell growth. Under normal conditions, cells grow, divide, and die in a controlled manner. However, in bone cancer, mutations in the DNA disrupt this process, causing cells to multiply uncontrollably and form a tumor. Over time, these cancer cells can infiltrate nearby tissues or spread to different parts of the body.

Several factors may contribute to the development of these mutations:

1. Genetic Predisposition – Inherited genetic conditions, such as Li-Fraumeni syndrome or hereditary retinoblastoma, can increase the risk of bone cancer. People with a family history of such syndromes may be more susceptible.
2. Radiation Exposure – High doses of radiation therapy, commonly used for treating other cancers, may raise the risk of bone cancer, especially when given at a young age.
3. Bone Disorders – Certain bone diseases, such as Paget’s disease of bone, which affects bone remodeling, can raise the likelihood of developing bone cancer.
4. Environmental Factors – Prolonged exposure to harmful chemicals or carcinogens may also contribute to DNA damage, potentially leading to cancerous growth in bone tissue.
5. Age and Rapid Bone Growth – While bone cancer can occur at any age, it is more commonly diagnosed in teenagers and young adults, possibly due to rapid bone growth during adolescence.

Although these factors may increase the risk, bone cancer can develop in individuals without any known predisposition. Ongoing studies strive to gain deeper insights into the root causes and possible preventive strategies.

Symptoms

There are various types of primary bone cancer, some of which can be more serious than others. Additionally, cancer signs and symptoms differ based on their type, location, and severity.

Pain

The primary sign of bone cancer is pain in the tumor area. At first, the pain may not always be there. The pain may be worse at night, can become more constant, and might get worse with activity. Sometimes, a tumor can cause a bone to break (fracture), which can cause a sudden onset of intense pain.

Swelling and Stiffness in the Joints

A tumor located near or within a joint may lead to swelling, tenderness, or stiffness. This means that a person may have a limited and painful range of motion.

Fracture

Most bone cancers don’t cause fractures, but they can weaken the bone. Individuals with a fracture near or through a bone tumor often feel sudden, intense pain in a bone that has been aching for months.

You may not be aware of the symptoms of bone cancer, whether it is cancer or not. When looking at an X-ray of another condition, your doctor might find the problem, such as a sprained ankle. But symptoms may include pain that:

• Located in the area of the tumor
• Dull or painful
• It gets worse when you’re active
• Will wake you up at night

Other symptoms related to bone tumors are

• Fevers
• Night sweats
• Swelling around a bone
• Limping
• Fatigue
• Weight loss

Types

Bone cancer is classified into different types based on the cells where it originates. The primary types of bone cancer include:

1. Osteosarcoma

Osteosarcoma is the most common form of bone cancer, mainly affecting children, teenagers, and young adults. It originates in osteoblasts, the bone-forming cells, leading to aggressive tumor growth. Osteosarcoma typically develops in long bones, such as the femur, tibia, and humerus, near the knee or shoulder. This cancer has a high tendency to spread to other parts of the body, particularly the lungs.

2. Chondrosarcoma

Chondrosarcoma arises from cartilage cells and is more common in middle-aged and older adults. It typically forms in areas with cartilage, such as the pelvis, shoulder, and ribs. Unlike osteosarcoma, chondrosarcoma tends to grow more slowly, but some aggressive forms can spread rapidly.

3. Ewing Sarcoma

Ewing sarcoma is a rare but aggressive cancer that primarily affects children and young adults. It can start in bone or soft tissues and is commonly found in the pelvis, ribs, and long bones like the femur. This type of cancer has a high risk of metastasizing to the lungs and other organs.

4. Chordoma

Chordoma is a rare form of bone cancer that occurs in the spine, mainly at the base of the skull and the sacrum (lower spine). It grows slowly but can invade surrounding tissues, including the spinal cord and nerves. Chordoma is more common in adults and requires specialized treatment due to its location.

5. Fibrosarcoma

Fibrosarcoma is a rare form of bone cancer that originates in fibrous connective tissue, often affecting the bones of the legs, arms, or jaw. It is most commonly diagnosed in middle-aged adults and has a higher likelihood of recurring after treatment.

6. Giant Cell Tumor of Bone

Giant cell tumors are usually benign but can become cancerous in rare cases. They typically develop in the long bones, such as the femur and tibia, near the joints. These tumors can cause pain, swelling, and bone destruction, requiring surgical intervention.

7. Undifferentiated Pleomorphic Sarcoma (UPS) of Bone

Undifferentiated pleomorphic sarcoma, formerly known as malignant fibrous histiocytoma, is a rare and aggressive cancer that affects the bone and soft tissues. It often appears in the legs or arms and has a high potential for metastasis.

Each type of bone cancer has distinct characteristics, growth patterns, and treatment approaches. Timely diagnosis and proper medical treatment can enhance outcomes and quality of life for those with bone cancer.

Stages

Bone cancer is classified into different stages based on tumor size, spread, and severity. Staging helps determine the appropriate treatment and prognosis. The primary staging systems used include the American Joint Committee on Cancer (AJCC) and the Enneking system.

Stage 1:

• The cancer is in its early stage, with a small, slow-growing tumor.
• It remains confined to the bone and has not spread to other tissues or organs.
• The tumor cells closely resemble normal bone cells, making it a low-grade tumor.

Stage 2:

• The tumor is still limited to the bone but is more aggressive and high-grade.
• Cancer cells appear more abnormal and grow at a faster rate.
• Although the cancer hasn’t spread, it poses a higher risk of progression.

Stage 3:

• The tumor remains in the bone but has spread to multiple areas within the same bone.
• It is considered high-grade, indicating a greater potential for spreading.
• This stage increases the risk of metastasis to distant sites if left untreated.

Stage 4:

• Cancer has spread beyond the original bone to other parts of the body, such as the lungs, liver, brain, or other bones.
• It is the most advanced stage and requires more aggressive treatment approaches.
• The prognosis depends on the extent of metastasis and response to treatment.

Understanding these stages helps doctors create personalized treatment plans, improving the chances of managing the disease effectively.

Risk Factors

Things that could make you more likely to get bone cancer include:

• Genetic conditions can be inherited from one generation to the next. For instance, certain genetic disorders like Li-Fraumeni syndrome and retinoblastoma (a type of eye cancer) can increase the risk of developing bone cancer.
• Additionally, bone tumors are more common in individuals who have undergone cancer treatments such as radiation therapy, stem cell transplants, or specific chemotherapy drugs.
• Paget’s disease is a condition that affects bone. Unfortunately, these benign bone conditions may also increase your odds.

Diagnosis

Your doctor will review your symptoms and medical history and may perform a physical exam. If you have any questions or concerns, consult your doctor. They will be performing imaging tests to check your bone pictures, for example:

• The X-ray: They show the tumors and how big they are.
• CT scans are medical images that can help doctors see inside a person’s body. A computer uses X-rays to create more detailed pictures.
• MRIs are a type of imaging that can be used to see inside the body. These medical devices use a solid magnet to visualise inside your body.
• A PET scan is a medical procedure that uses a radioactive isotope to produce body images. A technician will inject radioactive glucose (sugar) into your vein. The scanner detects cancer cells, which use more glucose than normal cells.
• A bone scan is a medical procedure that uses X-rays to check for fractures or other damage to bones. Then, the technician will inject another radioactive substance into the vein. It accumulates in your bones, making it detectable by a scanner.

Treatment

The common treatment for Bone Cancer includes:

• Limb salvage surgery: Your doctor removes the cancerous portion of the bone but leaves the surrounding muscles, tendons, and other tissues intact. They put a metal implant in place of the bone.
• Radiation therapy is a kind of cancer treatment that utilizes high-energy radiation to kill cancer cells. This uses powerful X-rays to destroy cancer cells and shrink tumors. Surgery and radiation are often used together to treat cancer.
• Chemotherapy is a type of cancer treatment. It utilizes drugs to destroy cancer cells. This kills the cancer cells with the cancer drugs. Your doctor may administer it before surgery, after surgery, or for metastatic cancer.
• Targeted therapy: Treatment directed explicitly at the cause of a disease or condition. This cancer treatment specifically targets certain genetic, protein, or molecular changes in and around cancer cells.

Frequently Asked Questions