Bone & Joint Cancer


Anatomy of the Bone

Bone is composed of protein called collagen, tissue, three types of cells – osteoblast (Cell builds new bone), osteoclast (cell that dissolves old bone), and osteocytes (cells that carry nutrients to the bones), and minerals called calcium phosphate which makes the skeleton hard and strong. The softer bones at each end of the bones are called cartilage and is made up of fibrous tissues mixed with a gel like substance called synovial fluid and works as a cushion between the two bones.

The occurrence of bone & joint cancer is exceedingly rare in adults and it starts in the cells of the bones. Bone cancer can occur when there is an uncontrollable growth in osteoblasts, osteoclast or in osteocytes and can be cancerous or benign. [cancer.net, 2020]

Different Cancer Types of The Bone

Ewing sarcoma and Osteosarcoma

These are the two most common types of bone cancer mainly occur in children and young adults. Ewing sarcoma most often develops in the leg, pelvis, rib, arm, or spine. Whereas osteosarcoma most often starts in a leg bone around the knee joint, either at the femur, which is the lower end of the thigh bone, or the tibia, which is the upper end of the shin bone. Both, Ewing and osteosarcomas metastasize primarily in lungs.


It is a cartilage producing bone tumor and it is malignant. Chondrosarcoma is least common. It occurs mainly in adults aging 45 to 75 years of age. The site of origin is pelvis, proximal long bones, ribs, scapula, and vertebrate.


Chordoma is a rare type of bone cancer that happens most often in the bones of the spine or the skull. It most often forms where the skull sits atop the spine (skull base) or at the bottom of the spine (sacrum). Chordoma happens most often in adults between 40 and 60, though it can happen at any age. It usually grows slowly and can be difficult to treat because its often located close to the spinal cord and other important structures, such as arteries, nerves, or the brain. [Mayo clinic, 2020]

Undifferentiated pleomorphic sarcoma (UPS)

Also known as malignant fibrous histiocytoma (MFH). UPS is an uncommon bone tumor, most closely related to osteosarcoma (see above). UPS of bone is usually found in adults. An arm or leg, especially around the knee joint, is the most common place for UPS to appear. It typically occurs in adults aging 32 to 80 years of age. [Dr Ammar Ashraf & Associate Prof. Frank Gaillard, Radiopedia.org]


It is a malignant, rare, and extremely aggressive subtype of soft tissue sarcomas. They are predominantly located either in deep soft tissue or adjacent to bones. Fibrosarcoma seldom derive from the cutis. In addition, fibrosarcoma can occur inside bones, either as a primary or secondary tumor.

Sarcoma of Paget’s disease of the bone

Paget’s disease of the bone generally occurs in older adults. It involves the overgrowth of bony tissue and frequently affects the skull. If Paget’s disease develops into cancer, it is usually an osteosarcoma. However, this is uncommon. [cancer.net, 2020]


Genetic mutations can be a leading cause of bone and joint cancer. People suffering from long term inflammation such as Paget’s disease might develop a risk of bone & joint cancer at the later stage. However, why one person develops the cancer is yet not truly clear. People who are exposed to radiations, have undergone bone marrow transplantation, occurrence in close relative or hereditary retinoblastoma are also at the risk of developing bone & joint cancer. Exposure to large doses of radiation, such as those given during radiation therapy for cancer, increases the risk of bone cancer in the future.

Signs & symptoms

The most common symptoms in all the three cancer- Osteosarcoma, Ewing Sarcoma and Chondrosarcoma are:

Bone pain and fracture

Swelling and tenderness near the affected area

Weakened bone, leading to fracture.

Decreased mobility or limping

Nerve injury

Diagnosis [American Cancer Society, 2008]

X-rays: Most of the bone cancers shows up on the X-rays of the bone. The bone at the site may look ragged instead of solid. It can also show up as a hole in the bone.

Radionuclide bone scan: Bone scans can show if a cancer has spread to other bones. It can find smaller areas of metastasis than regular x-rays. Bone scans also can show how much damage the cancer has caused in the bone.

CT (computed tomography) scan: CT Scans are helpful in staging cancer. They help show if the bone cancer has spread to your lungs, liver, or other organs. The scans show the lymph nodes and distant organs where there might be cancer spread.

MRI scan: MRI scans are often the best test for outlining a bone tumor. They are helpful for looking at the brain and spinal cord.

PET (Positron emission tomography) scan: PET scans use glucose (a form of sugar) that's attached to a radioactive atom. A special camera can detect the radioactivity. Cancer cells absorb a lot of the radioactive sugar because of their high rate of metabolism. PET scans are useful in looking for cancer throughout your entire body. It can sometimes help tell if a tumor is malignant or not. It's often combined with CT scans to better pinpoint some kinds of cancer.

Biopsy: A biopsy takes a piece of tissue from a tumor so that it can be looked at with a microscope and tested in the lab. This is the only way to know that the tumor is cancer and not another bone disease.