Bone is a rigid organ that constitutes part of the vertebrate skeleton. It consists majorly of collagen and calcium phosphate. Collagen is a protein that provides a soft framework and calcium phosphate is a mineral that provides strengths and hardens the framework. This combination of collagen and calcium makes bone strong and flexible enough to withstand stress. An adult human body consists of 260 bones each serving a unique purpose.
Bones are composed of two types of tissue:
- A strong, dense and hard outer layer, called cortical bone.
- A spongy inner layer called trabecular bone.
Bone serves multiple purposes in the human body. A few major functions are cited below:
- It provides structural support for the body.
- Bones protect internal organs from damage
- Bone marrow makes and stores blood cells.
- It also acts as a storage area for minerals.
- Bones play a key role in body movement.
Bone Cancer begins as an error in a cell's DNA. The error directs the cell to grow and divide in an uncontrolled way. These cells go on living, rather than dying at a set time. The accumulating mutated cells form a mass (tumor) that can invade nearby structures or spread to other areas of the body. Bone cancer is classified into primary and secondary Bone Cancer.
Primary Bone Cancer originates in the bone cells and secondary Bone Cancer migrates to the bone cells. Primary Bone Cancer is far less common than Cancer that spreads to the bones.
Types of Bone Cancer
Bone Cancer is categorized into several subtypes depending on the area of their origin. Each of the subtypes is unique and need different treatment. Some of the most common types of Bone Cancer are as follows:
- Osteosarcoma : It is the most common type of Bone Cancer accounting for 22 % of primary Bone Cancer in adults and 56% in children. It arises in the osteoid tissue of the bone. This tumor occurs mostly in the knee and upper arm areas of the body.
- Chondrosarcoma : It is the second most common Bone Cancer , accounting for 35% of Bone Cancer occurrences. It occurs in the cartilaginous tissue. People older than 40 years are at a higher risk of developing this cancer. Chondrosarcoma is most commonly found in the bones of the hips and pelvis. Since it is largely resistant to chemotherapy and radiation treating planning the prognosis often poses a challenge.
- The Ewing Sarcoma Family of Tumors (ESFTs): It is an aggressive and rare Bone Cancer that accounts for 8% of all Bone Cancer s in adults and 34% in children. ESFTs occur most commonly along the backbone and pelvis and in the legs and arms.
- Pleomorphic sarcoma: Pleomorphic sarcomas are cancers of soft tissues. It is also a rare type of Bone Cancer and accounts for only 5% of cases.
- Fibrosarcoma: It is an uncommon type of Bone Cancer and mostly arises behind the knee in adults.
- Chordoma: Chordoma is a very rare cancer that poses a higher risk to people over 30 years of age. The lower or upper ends of the spinal column are the area where it is often located.
- Spindle cell sarcoma: Spindle cell sarcoma is a rare type of Bone Cancer and tends to occur in adults over the age of 40.
There is no statistical report revealing the population-based incidence of Bone Cancer s in India. Bone sarcomas are rare tumours, approximating 0.2% of all cancers but malignant Bone Cancer cause significant morbidity and mortality. However, due to the advancement in surgical and medical oncology there have been some improvements in the survival of patients over the past few decades. Among the various types of bone sarcoma, Ewing sarcoma is the most common in India. The other common types being osteosarcoma (OGS), chondrosarcoma and synovial sarcoma.
Most common locations of Bone Cancer
People with Bone Cancer may experience some symptoms at a later stage when the cancer cells have spread to different organs of the body. The symptoms of Bone Cancer vary from one person to person depending on the location and size of the Bone Cancer and the previous health record of the patient. Generally, there is a gradual increase in the severity of the symptoms with time. Also, many of these symptoms might indicate some other health issue rather than Bone Cancer . So, it is recommended to consult a doctor, in case of spotting these symptoms, before reaching any conclusion.
When a bone tumour grows, it presses on healthy bone tissue and can destroy it, which causes the following symptoms:
- Sustaining pain – Pain is the most common symptom of Bone Cancer . The pain starts off as occasional and then becomes severe and constant. This pain might get worsened by exercise or the pain hits back at night when the muscles are relaxed. In children, this symptom is often mistaken for a sprain. If a child or teenager has bone pain that persists during the night then it′s always best to have it checked out by a doctor.
- Swelling - The swelling may not be felt until the tumour is quite large. It becomes more difficult to spot if the affected bone is deep within the body tissues.
- Reduced movement - If the cancer is near a joint, then the patient might face difficulty in movement.
- Broken bone – Cancer cells invade the healthy cells of the bone and make them fragile, which results in a fracture called pathological fracture.
- General symptoms - These may include tiredness, a high temperature or sweats and weight loss.
The exact cause of Bone Cancer is yet not known. Over the course of time, some factors that might increase the risk of Bone Cancer are unveiled. Some risk factors known till date are discussed below:
- Radiotherapy treatment
Exposure to high doses of radiation may cause cancerous changes in the bone cells.
- Bone conditions
Certain conditions of the bone may increase the chances of developing Bone Cancer .
- Paget’s disease of the bone sometimes increases the risk of Bone Cancer especially in older people over 50-60 years of age. Paget disease makes the bone heavy, thick, and brittle. They are weaker than normal bones and more likely to fracture. Bone Cancer develops in about 1% of those with Paget disease, usually when many bones are affected.
- Ollier's disease is a rare condition of the bones that cause tumors to grow which can increase the risk of Bone Cancer .
- Genetic conditions
- A rare genetic condition called hereditary cancer predisposition, also known as Li-Fraumeni syndrome increases the risk of developing Bone Cancer to some extent. Li-Fraumeni creates a faulty version of a gene that usually helps stop the growth of tumours in the body. Sometimes, people with Li- Fraumeni develop multiple tumours often in their childhood or during adolescence.
- Multiple exostose syndrome is an inherited condition that causes many bumps on a person’s bones. These bumps are made mostly of cartilage. They can be painful and deform and/or fracture bones. This disorder is caused by a mutation in any one of the 3 genes EXT1, EXT2, or EXT3. Patients with this condition have an increased risk of chondrosarcoma.
- Other conditions
- Retinoblastoma is a rare type of eye cancer which can sometimes lead to Bone Cancer , as the same inherited faulty gene can be responsible for both conditions. Also, if radiation therapy is used to treat the retinoblastoma, the risk of osteosarcoma in the bones around the eye is even higher.
- Another syndrome that induces Bone Cancer is the Rothmund-Thomson syndrome
- Babies born with an umbilical hernia are three times more likely to develop Ewing sarcoma.
Most of the causes of Bone Cancer are hereditary or genetic that is beyond our control. However, leading a healthy life and taking certain precautions might aid in avoiding this deadly disease. Here are a few tips that are easy to follow and offer great resistance to the disease:
- Being aware of the genes and locating if anyone in their bloodline has been diagnosed with the problem in the past.
- Leading a healthy lifestyle and avoiding harmful habits like smoking, alcohol or stress helps in avoiding Cancer.
- Diet and nutrition play a pivotal role in preventing any cancer. Keeping a track of caloric intake and sticking to a low-fat diet, including fruits and vegetables and reducing the intake of saturated fat and red meat helps in avoiding the disease.
- Physical exercise and yoga are effective in maintaining a healthy body and controlling obesity. A healthy and fit body helps in preventing Cancer.
- It is crucial for cancer to be diagnosed before metastasis. Consulting an expert for screening and detection of the condition before it spreads is very necessary.
Some herbal and organic tips can also be followed to prevent Bone Cancer . The use of turmeric and ginseng in preparing food helps in avoiding any form of cancer. Turmeric has a therapeutic compound called curcumin which possesses the properties to fight cancer and improve the immune system of the body. A clinical trial of curcumin proved that it could stop the precancerous changes becoming cancer. Ginseng is the herb which hinders the formation of cancer cells, while certain green tea extracts are also effective in hindering the growth of cancer tissue. Clinical research on the above topic is still in progress and an appropriate conclusion is yet to be reached.
Bone Cancer is staged into 4 stages, based on the severity and spread of the Cancer cells. The treatment options for Bone Cancer are planned based on the stage of the Cancer and overall health of the patient.
- Stage I: If the Cancer is limited to the bone and hasn′t spread to other areas of the body then it is termed as stage I. Cancer at this stage is considered low grade and not aggressive. It is further classified into two subgroups:
- Stage IA: The tumor is low grade and is smaller than 8 cm. It has not spread to any lymph nodes or to other parts of the body and is marked as T1, N0, M0, G1/G2.
- Stage IB: The tumor is low grade but is larger than 8 cm. It has not spread to any lymph nodes or to other parts of the body. It is marked as T2, N0, M0, G1/G2.
- Stage II: If the cancer is limited to the bone and hasn′t spread to other areas of the body then it is characterized as stage II. In this stage, the cancer has turned high grade and aggressive. It is further categorized into:
- Stage IIA: The tumour is of high grade and its size varies from 2 to 8 cm. It has not spread to any lymph nodes or to other parts of the body. It is marked as T1, N0, M0, G3/G4.
- Stage IIB: The tumour is of high grade and is larger than 8 cm. It has not spread to any lymph nodes or to other parts of the body. The tumour is described as T2, N0, M0, G3/G4.
- Stage III: At this stage, Bone Cancer has spread to two or more places on the same bone. The cancer is of high grade and is usually very aggressive. There are multiple high-grade tumours in the primary bone site, but they have not spread to any lymph nodes or to other parts of the body. It is described as T3, N0, M0, G3/G4.
- Stage IV: This stage indicates that tumor may be of any size or grade and has spread beyond the bone to other areas of the body, such as the brain, liver or lungs.
- Stage IVA: The cancer cells have spread to the lung(s) (any G, any T, N0, and M1a).
- Stage IVB: The tumor has spread to the lymph nodes (any G, any T, N1, and any M), or to another organ besides the lung (any G, any T, any N, and M1b).
The tremendous plunge in the development of science and technology has aided better treatment facility which resulted in more successful cases of Bone Cancer recovery in recent years. Survival rates are basically an indicator that helps in analyzing the expected life span of the patients based on previous records of patients with the same condition. However, these rates do not claim the same life expectancy for each individual.
Yes, today there are a number of ways that help in detecting Bone Cancer at a very early stage. Increased awareness among the people about this disease has helped in identifying the hideous disease at early stages. Some tests and procedures for Bone Cancer diagnosis are discussed below:
- Bone scan: A liquid with radioactive material is injected into a vein which gets accumulated in the abnormal areas of the bone. The cancer cells can then be spotted by using a scanner.
- Computerized tomography (CT): It is used to generate a clear 3-D image of the inside of a bone. It is a painless procedure and helps to identify if the cancer cells have metastasized and to which locations.
- Magnetic resonance imaging (MRI): The device uses a magnetic field and radio waves to create detailed images of the specific bone or part of a bone.
- Positron emission tomography (PET): In this procedure, a small amount of radioactive glucose is injected into a vein and a scanner is used to make detailed, computerized pictures of areas inside the body where the glucose is used. As cancer cells often use more glucose than normal cells, the pictures can be used to find cancer cells in the body.
- X-rays: An X - ray scan can detect damages caused by the cancer cells. It also gives information about the location, size and shape of the tumour. An X-ray also helps in detecting any new cells that have started to form around the tumour.
- Blood tests: Certain blood tests may also be recommended by the doctor to determine the level of an enzyme called alkaline phosphatase. The presence of cancerous cells may cause the raised level of this enzyme. But this test alone cannot certify the presence of Bone Cancer as there are multiple scenarios where this enzyme is found at a high level.
- Bone biopsy: A sample of bone tissue is extracted and examined for cancer cells. This is the most reliable way to diagnose Bone Cancer . A core needle biopsy involves inserting a long, thin needle into the bone and removing a sample, while an open biopsy involves making an incision in the target bone area and surgically removing a sample of tissue.
Treatment options for Bone Cancer depend on several factors, including the type, size, location, and stage of the cancer, as well as the person’s age and general health. Some of the most common and effective treatment options for Bone Cancer are given below:
- Surgery is the usual treatment for Bone Cancer . The entire tumor along with negative margins is removed through surgery.
- Limb-sparing surgery, have made it possible for many people to avoid amputation.
- Even when the Bone Cancer has metastasized and spread to the lungs then also the patient may be cured using surgery. An operation to remove the part of the lung that′s affected is used to cure metastatic cancer. This operation is called a thoracotomy.
- Neoadjuvant Chemotherapy: In this procedure, medicinal aid is used to shrink the size of tumour before surgery. Due to its effective results and good response, neoadjuvant chemotherapy is now included as a routine procedure to treat cancer. Research revealed that neoadjuvant chemotherapy can significantly improve the survival rate of the patient and so most often the therapy consists of neoadjuvant chemotherapy followed by wide surgical resection and subsequent adjuvant chemotherapy.
- Chemotherapy: In this procedure, anticancer drugs are used to kill or inhibit the growth of cancer cells. Patients with Bone Cancer usually receive a combination of anticancer drugs. It is an important part of the treatment for most osteosarcomas, spindle cell sarcomas and Ewing’s sarcomas.
Common drugs for osteosarcoma include:
Common drugs for Ewing sarcoma include:
- Cisplatin (Platinol)
- Doxorubicin (Adriamycin)
- Ifosfamide (Ifex)
- Vincristine (Oncovin, Vincasar)
- Doxorubicin (Adriamycin)
- Cyclophosphamide (Cytoxan, Neosar)
- Ifosfamide (Ifex)
- Etoposide (Toposar, VePesid)
- Dactinomycin (Cosmegen)
- Radiation therapy: In this procedure, high-energy x-rays are used to kill cancer cells. The most common type of radiation treatment is called external-beam radiation therapy, in which radiation is given from a machine outside the body. If radiation is given using implants, then it is called internal radiation therapy or brachytherapy. For Bone Cancer , radiation therapy is most often used if the tumour cannot be removed by surgery. Radiation therapy may also be done before surgery to shrink the tumour, or it may be done after surgery to destroy any remaining cancer cells as per doctor’s recommendation. Side effects from radiation therapy may include fatigue, mild skin reactions, upset stomach, and loose bowel movements.
- Cryosurgery is the use of liquid nitrogen to freeze and kill cancer cells. This technique can sometimes be used to destroy the tumour.
Yes, Bone Cancer is curable through surgery when detected at an early stage. Even at a later stage, surgery, chemotherapy, radiation therapy and several modern treatments help in curing the disease.
We would suggest visiting the doctor if there is persistent, severe or worsening bone pain, or if you experience any of the symptoms mentioned above. Also, if you have a high risk of developing Bone Cancer then keeping up a regular check on the health factors, helps in early diagnosis. While it's highly unlikely that the symptoms are caused by cancer, it's best to be sure by getting a proper diagnosis.
Being aware of the health updates and knowing about your family health history helps in identifying the risk factors that might lead to the development of Bone Cancer .