Bone cancer occurs when unusual cells grow out of control in your bone. It destroys the normal bone tissue. It may start in your bone or spread there from other parts of your body, which is called metastasis or secondary bone cancer. It is important to note that most cancers can spread to the bones. However, people with prostate and breast cancer have a particularly high risk of developing bone cancer.
Bone cancer is rare. Most bone tumors are benign, which means they are not cancer and do not spread to other areas of your body. However, they may still weaken your bones and lead to other problems or broken bones. To understand bone cancer, it’s good to understand a little about normal bone tissue:
The adult human skeletal system consists of 206 bones. Bones allow people to stand upright, protect the internal organs, and attach to muscles, which allow movement. They are connected to other bones by bands of fibrous, tough tissue called ligaments. Cartilage protects and covers the joints where bones come together. They are hollow and filled with bone marrow, which is the spongy, red tissue that produces blood cells. Whereas the cortex is the hard, outer portion of the bone.
Bone consists of collagen, which is a soft, fibrous tissue, and calcium phosphate, a mineral that helps strengthen and harden the bone. There are 3 types of bone cells:
- Osteoblasts: Cells that build new bones
- Osteoclasts: Cells that break down and remove old bones
- Osteocytes: Cells that carry nutrients to the bones
Cancer can begin in any part of any bone. It starts when healthy cells in the bone change and grow out of control, making a mass called a tumor.
Types of Bone tumours
Most bone tumours are benign or non cancerous. Some of the most common types of benign bone tumors are:
- Osteochondroma is the most common type. It mostly happens in people under the age 20.
- Osteoid osteoma often happens in long bones, usually in the early 20s.
- Giant cell tumor is usually in the leg. In rare cases, these can also be cancerous.
- Osteoblastoma is a rare tumor that grows in the spine and long bones, mostly in young adults.
- Enchondroma usually forms in bones of your feet and hands. It often has no symptoms.
On the other hand, primary bone cancer, or bone sarcoma, is a cancerous tumor that starts in the bone. Below are some of the most common types of primary bone cancer:
- Ewing’s sarcoma often happens in people between the ages of 5 and 20. The ribs, pelvis, and leg are the most common sites. It can also start in the soft tissue around the bones.
- Osteosarcoma mostly forms around the upper arm and knee. Teens and young adults are most likely to get it.
- Chondrosarcoma happens most often in people between ages 40 and 70. The hip, pelvis, arm, leg, and shoulder are common sites of this cancer, which starts in cartilage cells.
Symptoms & causes
When a bone tumor grows, it presses on healthy bone tissue and can destroy it, leading to symptoms like pain, joint swelling and stiffness, limping, and other less common symptoms such as fever, weight loss, and anemia (low level of red blood cells). Having said that, you should make a visit to the doctor if you develop bone pain that comes and goes, becomes worse at night, and isn’t helped by over-the-counter pain relievers. The cause of most bone cancers is unknown. While a small number of bone cancers have been linked to hereditary factors, others are related to previous radiation exposure.
Finding cancer early – while it’s small and before it has spread – often allows for more treatment options. A variety of imaging tests can be used to detect bone tumors, including bone cancers. Really early bone cancers may or may not be apparent on plain
X-rays. MRI scans and CT scans are more precise in defining the location of bone cancers. A bone scan is a test that uses radioactive material to make images of the entire skeleton. It may allow the localisation of bone cancer anywhere in the body. The test is not specific for bone cancers and can also reveal areas of inflammation as found with fractures, arthritis, and infections. At present, there are no screening tests available to find early bone cancers.
After diagnosis, doctors usually determine the stage of bone cancer. Staging is a process of trying to find out the severity and spread of cancer. It helps in understanding how serious it is and what treatment one must follow. There are four stages of bone cancer: from I through IV. By the rule, the lower the number, the lower the spread of cancer. The staging system which is mostly is the TNM method. There are four primary pieces of information in this method:
1. The size of the tumor (T) – It tells how extensive the cancer is and if it has affected more bones than one.
2. The spread of nearby lymph nodes (N) – It detects if the cancer has spread to the lymph nodes.
3. The metastasis or the spread of cancer to the distant site (M) – It indicates if cancer has spread to either the lungs alone or distant sites like the liver.
After the TNM score is assigned, bone cancer is classified into one of the stages below:
Stage I – The cancer cells are still localised to the bone and the tumor is considered low-grade. It is divided into two sub categories:
- Stage IA: The cancers are less than 8 cm in size.
- Stage IB: The tumor is larger than 8 cm, or can be found in several places within the same bone.
Stage II – These cancers are still localised to the bone but they are considered high-grade. It is divided into two sub categories:
- Stage IIA: The tumor is less than 8 cm in size.
- Stage IIB: The tumor is larger than 8 cm in size.
Stage III – Primary bone cancers at this stage are still localised to the bone, but they are high-grade and have spread to various places within the same bone.
Stage IV – This stage cancer is the most advanced form of the disease. Here the cancer has spread beyond the bone to other areas of the body. The cancer may be categorised as stage IVA or IVB:
- Stage IVA: The cancer has spread to the lungs.
- Stage IVB: The cancer has spread to the lymph nodes or the tumor is of any grade and size and has spread to another organ besides the lung. This stage is the same as metastatic cancer.
The grade of cancer – Indicates how abnormal the cells appear when viewed under a microscope. The grading scale for cancer of the bone is from 1 to 3. Low-grade (G1) cancers grow and spread slower than high-grade (G3 or G2) cancers.
The treatment options for bone cancer are based on the stage of the cancer, the type of cancer you have, your overall health, and your preferences. Treatment options for bone cancer include surgery, radiation therapy, chemotherapy, cryosurgery, and targeted therapy. People who have been treated for bone cancer stand at an increased likelihood of developing late effects of treatment as they age. These late effects include physical problems involving the lung, heart, hearing, bone, and fertility; neurological problems; and sometimes second cancers (myelodysplastic syndrome, acute myeloid leukemia, and radiation-induced sarcoma).
Bone cancer sometimes metastasizes, particularly to the lungs, or can recur either at the same location or in other bones in your body. People who have had bone cancer should check with their doctor regularly and should report any unusual symptoms right away. Follow-up varies for different stages and types of bone cancer. Regular follow-up care ensures that changes in health are monitored and that problems are treated as soon as possible.
Survivorship and prevention of blood cancer
Life after cancer can be anything but normal. Survivorship is a broad term that includes not only people who have been diagnosed with cancer at some point in their life, but also the family members and friends of people who have been diagnosed with cancer. Following the treatment period, during which cancer patients have a lot of support and helpful information, survivors may feel at a loss for this support, with several unanswered questions. They may experience a mixture of strong feelings, including joy, relief, concern, guilt, and fear. Some people may appreciate life more after a cancer diagnosis and have gained a greater acceptance of themselves. Others become very anxious about their health and uncertain about coping with everyday life. Every survivor has individual concerns and challenges. With any challenge, the first step is being able to recognise your fears and talk about them.
It is never too early or late to take care of your bones. There are many things you can do to keep the bones strong and healthy. Maintaining a healthy diet is one of the best ways to prevent bone cancer. Eating foods rich in vitamin D and calcium, doing plenty of exercise, and having good lifestyle habits help keep our bones healthy in the long run. Eating well beforehand can also help you better cope with side effects of treatments and withstand higher doses of certain medications. In fact, being well-nourished can boost the effectiveness of some cancer treatments. Remember healthy diet and lifestyle choices can go a long way in lowering the risk of bone cancer. So stay healthy, stay safe!