Osteosarcoma is a type of bone cancer commonly diagnosed in young adults, adolescents and children. According to experts like Best Orthopedic Surgeon in Islamabad, osteosarcoma or osteogenic sarcoma is the most prevalent type of bone cancer. As with any tumor, the bone cells grow at an abnormal rate in osteosarcoma and help to make new bone that is much weaker in strength. Read on to know more about osteosarcoma, its symptoms, diagnosis and management:

What is osteosarcoma?

The word ‘osteo’ refers to bones, while ‘sarcomas’ are tumors of the connective tissue that support the body—including muscles, cartilages and bones. Osteosarcoma is, therefore, tumor of the bones, with uncontrolled cell growth and formation of immature, diseased bone which appears similar to the regular bone but is much more fragile.

The incidence of osteosarcoma is higher in teenaged boys who are undergoing a growth spurt. Thus, the risk is higher in taller children. Other risk factors include: having history of radiation therapy for any other type of cancer and taking chemotherapeutic drugs like alkylating agents and having history of hereditary diseases like Paget’s disease, Bloom syndrome, retinoblastoma, Li-Fraumeni syndrome and Werner syndrome.

Osteosarcoma can occur in any bone; however, the common sites are the long bones of the limbs, particularly:

• Femur or thigh bone
• Knee area—either the end of femur (thigh) bone or start of tibia (upper part of shinbone)
• Upper part of the arm bone close to the shoulder—proximal humerus is the other most common site of osteosarcoma.
• Less common site includes: jaw, skull and pelvis
• It is rare for osteosarcoma to occur in soft tissues, abdominal organs and the chest.

What are the types of osteosarcoma?

Osteosarcoma is divided into subtypes, based on the grade of the tumor. The three grades for tumor classification are: high-grade, low-grade and intermediate-grade. Each grade depicts the degree of differentiation and growth.

For high-grade tumor, the speed of spread and growth is fast and the tumor will likely metastasize quickly. The low-grade tumor, on the other hand, mostly remains localized and grows slowly. The intermediate-grade tumor falls between the two categories, and for clinical purposes, is treated the same way as low-grade tumors.

The nine types of high-grade osteosarcomas are:

• Small cell
• Osteoblastic
• Pagetoid
• Post-radiation
• Chondroblastic
• Telangiectatic
• Fibroblastic
• High-grade surface
• Extraskeletal

The low-grade osteosarcomas include these two types:

• Intramedullary or intraosseous low-grade tumors
• Parosteal low-grade tumors

The intermediate-grade osteosarcoma is:

• Periosteal tumor

How is osteosarcoma diagnosed?

The diagnosis of osteosarcoma is based on a thorough history and examination by the healthcare provider.

• Physical exam: includes checking for unusual lumps and bumps around the bones.
• Imaging techniques: are used to visualize the bones and check for fractures or unusual growths. These include: X-rays, bone scans, CT scans, PET scans and MRI scans. The PET scan is used in cases of high suspicion to check for metastasis of the cancerous cells to other parts of the bones.
• Bone biopsy: is the confirmatory test whereby a small sample of the bone involved is visualized under the microscope to check for cancerous cells, rate of differentiation and the spread of cancer beyond the bones.

What are the symptoms of osteosarcoma?

The symptoms of osteosarcoma include:

• Pain, particularly at night
• Unexplained fever
• Swelling or lumps around the ends of long bones
• Increased bone pain with lifting—particularly with arm involvement
• Broken bones without history of trauma or a clear cause with simple movement
• Soreness in the bones or joints that comes and goes
• Limping—if the leg bones are involved
• Limited movement—especially if a joint is involved
• Pain and soreness after exercise that doesn’t recede

How is osteosarcoma treated?

The treatment of osteosarcoma is based on surgery and chemotherapy. Orthopedic Surgeon performs surgery for the removal of tumors in the affected bone. In limb-salvage surgery, this procedure is done without amputation. Surgery may follow or precede chemotherapy and radiation therapy to kill the remaining cancer cells.