Bone Cancer, Including Osteosarcoma and Ewing’s Sarcoma

Primary bone cancer is a general term that refers to several relatively rare malignancies, including osteosarcoma and Ewing’s sarcoma, which develop in the body’s skeletal system. Secondary (metastatic) bone cancer originates in another part of the body, such as a lung, a breast or the prostate, then spreads to a bone. Metastatic bone cancer is more frequently diagnosed than primary bone cancer. Some common bone metastasis sites include the bones in the hips, thighs, shoulders and spine.

Because bone cancer can affect many different areas of the body, its biology is diverse and its treatment can vary widely. Therefore, it is important to seek specialized care through a high-volume sarcoma program. The multidisciplinary team in the Sarcoma Center of Excellence in Tampa General Hospital’s Cancer Institute has extensive experience in treating all types of bone cancer, including those that are highly complex and exceedingly rare. We make world-class care available to everyone who needs it.

What Is Osteosarcoma?

Also known as osteogenic sarcoma, osteosarcoma is the most common type of primary bone cancer. The cancer originates in the cells that produce new bone tissue (osteoblasts). The bone tissue produced by cancerous osteoblasts is much weaker than that produced by healthy osteoblasts.

Most often, osteosarcoma affects children, teenagers and young adults, but it can develop at any age. The tumors usually form in areas of rapid bone growth, such as the:

• Lower thighbone (distal femur) near the knee
• Upper shinbone (proximal tibia) near the knee
• Upper arm bone near the shoulder (proximal humerus)

Osteosarcoma can also occur in the pelvis, hip, shoulder and jaw, particularly in adults

Types of Osteosarcoma

Based on the appearance and behavior of the cancerous cells when viewed under a microscope, osteosarcoma can be classified as:

• High grade – The cancerous cells look markedly different than healthy osteoblasts and are rapidly dividing.
• Intermediate grade – In terms of differentiation and aggressiveness, the cancerous cells fall in the middle of the spectrum.
• Low grade – The cancerous cells closely resemble healthy bone cells and are replicating at only a slightly accelerated rate.

What Is Ewing Sarcoma?

A type of bone cancer that primarily affects children and young adults, Ewing sarcoma is named for Dr. James Ewing, the physician who first described the tumor type in the 1920s. This type of cancer often develops during puberty, which is a period of rapid bone growth. When viewed under a microscope, the cancerous cells are small, round and blue.

While Ewing sarcoma can originate in any bone, it is most often found in the:

• Hip
• Ribs
• Femur
• Tibia
• Humerus

Additionally, extraosseous Ewing sarcoma is a rare subtype that forms in muscles and other soft tissues near bones.

What Is the Difference Between Osteosarcoma and Ewing Sarcoma?

Osteosarcoma and Ewing sarcoma are the most common types of pediatric bone cancer. The conditions share many symptoms, such as bone pain and swelling, but the tumors form in different areas of the body. While osteosarcoma—the more common of the two—usually originates in the bones around the knee, Ewing sarcoma is more likely to affect the hip, femur, tibia, humerus or ribs. It is also more likely to invade nearby soft tissues, such as muscles, fat and nerves.

Due to the differences between osteosarcoma and Ewing sarcoma, their treatment can vary. For instance, radiation therapy is more often used to treat Ewing sarcoma than osteosarcoma.

What Is Chondrosarcoma?

Chondrosarcoma originates in the cartilage at the ends of bones, most often in the leg, arm and pelvis. Unlike osteosarcoma and Ewing sarcoma, which mainly affect children and young adults whose bones are still growing, chondrosarcoma is usually diagnosed in patients older than 50.

What Causes Bone Cancer?

Researchers have not yet pinpointed the precise causes of the cellular DNA changes that lead to the development of bone cancer. Some known risk factors include:

• Certain inherited conditions, such as Li-Fraumeni syndrome, Rothmund-Thompson syndrome and hereditary retinoblastoma
• Certain noncancerous bone conditions, such as Paget’s disease
• Exposure to high doses of radiation

What Are the Symptoms of Bone Cancer?

The most common sign of bone cancer is pain, which can occur if a growing tumor presses on nearby tissues or if the cancer weakens a bone to the point that it fractures. Some people also experience:

• Bone tenderness
• Stiffness
• Fatigue
• Fever

How Is Bone Cancer Diagnosed?

After performing a physical examination, a physician may order imaging studies or blood work as part of the diagnostic process. For instance, a high level of a specific enzyme known as alkaline phosphatase is often present in the blood when bone-forming cells are very active, such as when a young child’s bones are growing or when a broken bone is mending. In other situations, however, it could be a sign that a tumor is creating abnormal bone tissue. To make a definitive diagnosis, a physician will order a biopsy of the suspicious bone tissue.

How Is Bone Cancer Treated?

While surgery is the main form of treatment for bone cancer, some patients receive chemotherapy or radiation therapy (such as brachytherapy), either alone or in combination with surgery. The optimal treatment plan is determined based on the type, size and location of the tumor and whether the cancer has spread.

Benefit From World-Class Care at TGH

The experienced specialists in TGH’s innovative Sarcoma Center of Excellence take a personalized approach to bone cancer treatment. We work closely with each patient with the goal of achieving the best possible outcome while preserving the form and function of the affected bones. Toward that end, we regularly review all newly diagnosed sarcoma cases in a Sarcoma Tumor Board meeting, where each pertinent medical specialty is represented and provides recommendations. Working together, we develop a tailored treatment plan for each patient and review it with the patient on the same day. Through real-time collaboration, we avoid delays and provide our patients with comprehensive and timely care.

To request an appointment with a bone cancer specialist at TGH, contact us at (813) 844-4151

The multispecialty team in the Cancer Institute at Tampa General Hospital takes a personalized approach to bone cancer treatment, working closely with each patient to achieve the best possible outcome while preserving the form and function of the affected bones.