What is bone cancer? 

Bone cancer is a rare type of cancer that can begin in any bone, but commonly affects long bones and pelvic bones. Primary bone cancers, which are cancers that begin in the bone, are different from secondary or metastatic bone cancers that are cancers that develop elsewhere and then spread to the bone. Bone cancer is rare in adults and occurs more in children because of the rapid growth spurts during puberty. Both the outlook and treatment depend on the type of bone cancer.

What are the types of bone cancer?

Bone cancers are classified into several types based on the type of cell from which the tumor develops.

The most common ones are: 

Osteosarcoma:  This is the most common form. It starts at cells that grow bone tissue. It occurs especially in young people under the age of 20, in the long bones of the leg or the arm.

Chondrosarcoma:  it is the second most common type among bone cancers. It occurs in the cells that produce cartilage, usually in the pelvis area. People between the age of 40 and 70 are more likely to get Chondrosarcoma.

Ewing’s sarcoma: it is rare cancer that grows in the bones or in the cells surrounding soft tissue. The most common sites of Ewing’s sarcoma are the pelvis, long bones of legs and arms, and the chest wall. This type of bone cancer affects mainly children and young adults.

What are the symptoms of bone cancer?

Signs of bone cancer include:

• Bone pain: which is the most frequent and common symptom. It begins as a feeling of tenderness and progresses to become a persistent continuous pain. The bone ache gets worse over time and with activity and it isn’t helped by taking pain relievers.
• Tenderness and stiffness of the bone
• Weakened bones: leading to easy and multiple fractures
• Redness and swelling near the affected area making the movement more and more difficult.
• A palpable hard mass can develop
• Fatigue and tiredness
• Unexplained weight loss
• Night sweats

What are the causes and risk factors of bone cancer? 

Generally, the exact causes behind bone cancers are unknown. Nevertheless, some types have been linked to genetic and hereditary factors or to radiation exposure. That’s why some factors can increase the incidence of bone cancers. These factors include : 

Previous radiation exposure for example during radiotherapy especially for young patients who have received high doses.

Inherited conditions and genetic factors.

Li-Fraumeni syndrome LFS: is a rare hereditary disorder that predisposes its carriers to develop cancer, including primary bone cancer.

Other non-cancerous bone disorders such as Paget’s bone disease can increase the risk of getting this type of cancer, although the risk is not significant.

Ollier's disease, which is a benign condition that affects the cartilage, can increase the risk of bone cancer.

Retinoblastoma: Patients who are diagnosed with retinoblastoma, an eye cancer that begins in the retina, face an increased risk of developing bone sarcomas.

Diagnosis of bone cancer

When to seek medical care? 

If you are experiencing some of the bone cancer’s symptoms (especially bone pain) mentioned above or you are carrying one of the risk factors, then you should consider making an appointment with your doctor to check your general health and to get a proper diagnosis. 

How to confirm the diagnosis?

The doctor will ask you to describe your symptoms in a detailed manner. Then, he will be examining the affected area of your body. After that, he can decide whether you need to have other tests to confirm the initial diagnosis. 

Here are some tests that you may be asked to have in order to diagnose and assess bone cancer: 

Blood tests: to check your general health.

X-rays: to reveal the damage to the bone. It is an effective way to detect bone cancer or any other bone abnormalities, such as fractures.

Computerized Tomography Scan: An X-Ray test that can accurately detect any bone abnormalities.

A magnetic resonance imaging scan: This test helps with assessing the size and the spread of the tumor.

Biopsy: a procedure in which a small bone sample is removed to check if this bone is affected by cancer. The bone sample will be examined under a microscope in a laboratory. This procedure is the definitive way of diagnosis and can even determine the type and the grade of cancer.

The staging of bone cancer 

Primary bone cancer is classified in stages to describe its evolution and prognosis.

Stage I 

The cancer is low grade and hasn’t spread from the bone 

Stage II

The cancer is high grade but hasn’t spread outside the bone

Stage III

Multiple tumors in the same bone with the high grade but hasn’t spread outside the bone

Stage IV

Bone cancer has spread to other organs and surrounding tissues

After diagnosing the Bone cancer

If all the tests have confirmed the diagnosis of bone cancer, you will be referred to a specialized center to treat this condition.

Doctors will talk to you about what you will experience and will discuss the plan of treatment. 

Shock, anxiety, and confusion are normal reactions after discovering the diagnosis of bone cancer. You can talk to your doctor about your feeling and he will give you support and help you cope with this distressing experience.

How is bone cancer treated?

Treatment 

Primary bone cancer is usually treated either with surgery, chemotherapy, radiotherapy, or even a combination of all these suggested treatments.

Limb-sparing surgery

This is the most common type of surgery to treat bone cancer. It consists of removing the section of the cancerous bone but sparing the limb. Under general anesthesia, the affected parts of the bone are removed and placed with an implant or prosthesis as a type of reconstruction.

Whenever it is impossible to remove all of the tumors without affecting the limb, amputation may be the alternative solution. 

After the surgery, a period of rehabilitation will be needed. This involves physiotherapy sessions and sometimes, occupational therapy. 

Chemotherapy 

Chemotherapy is used to either destroy cancer cells or shrink the tumor before surgery. It can also be used to prevent the recurrence of cancer. In advanced stages of bone cancer, chemotherapy is used as a palliative treatment, to control the symptoms and relieve the effects of the tumor. This form of treatment uses powerful cancer-killing medications that are given in regular cycles. 

Chemotherapy has some side effects: 

• tiredness
• nausea and vomiting
• diarrhea
• hair loss

But those effects are temporary; they usually disappear after stopping the treatment.

Radiotherapy or Radiation therapy

This form of treatment usually uses high-energy rays to damage cancer cells. It may be prescribed before undergoing the surgery to help make it easier and safer, or even after surgery in order to reduce the risk of having the cancer cells regrow. Radiotherapy is given in daily sessions as directed by the doctor.

The exposure to radiation during radiotherapy can lead to side effects, such as: 

• fatigue
• skin irritation
• joint pain
• local hair loss in the part of the body being treated

The treatment plan is decided by a team of healthcare professionals in a specialized center and all the available options are discussed with the patient. 

Conclusion: Long term outlook

Bone cancer’s outlook usually depends on different factors such as the patient's age, the type of bone cancer, its stage, and its grade when the patient is first diagnosed.

Generally, bone cancer is more likely to be cured in healthy people whose cancer hasn't spread.

Bone cancer treatments can have side effects and over time, they can cause problems with the cardiovascular system, with the lungs, and/or with fertility. Thus, regular checkups with your doctor are necessary in order to watch for probable complications and to make sure the bone cancer doesn’t return.