CONDITIONS AND TREATMENTS

Benign & Malignant Tumors

A tumor is a lump or mass of tissue that forms when cells divide uncontrollably. A growing tumor may replace healthy tissue with abnormal tissue. It may also weaken bone, causing it to fracture. For most bone tumors, the cause is unknown. Occasionally, infection, stress fractures, and other non-tumor conditions can closely resemble tumors.

Benign bone tumors are non-cancerous and not typically life threatening. There are many types of benign bone tumors. The most common types include non-ossifying fibroma, unicameral (simple) bone cyst, osteochondroma, giant cell tumor, enchondroma, and fibrous dysplasia.

Malignant tumors are cancerous and can spread cancer cells throughout one’s body through the blood or lymphatic system, a process known as metastasis.

Cancer that begins in bone is called primary bone cancer. Cancer that begins somewhere else in the body and spreads to the bone is known as secondary bone cancer. The four most common types of primary bone cancer are:

  • Multiple Myeloma – A malignant tumor of bone marrow which is the most common form of primary bone cancer. It affects approximately 20 out of one million people per year. Most cases are seen in patients 50-70 years old. Any bone can be involved.
  • Osteosarcoma – The second-most common bone cancer. It occurs in 2-3 people per million annually. Most of these tumors occur around the knee and are found in teenagers. Other common locations include the hip and shoulder.
  • Ewing's Sarcoma – Commonly occurs in people age 5-20. The most common locations are the upper and lower leg, pelvis, upper arm, and ribs.
  • Chondrosarcoma – Occurs most commonly in patients 40-70 years of age. Most cases occur around the hip and pelvis or shoulder.

Symptoms

Most patients with a bone tumor will experience pain in the area of the tumor. The pain is generally described as dull and achy. It may or may not get worse with activity. The pain often awakens the patient at night.

Although tumors are not caused by trauma, occasionally injury can cause a tumor to begin hurting. Injury can cause a bone weakened by tumor to break, leading to severe pain. Some tumors can also cause fevers and night sweats.

Many patients will not experience any symptoms, but will instead notice a painless mass.

Diagnosis

If you suspect that you might have a bone tumor, see your doctor as soon as possible for diagnosis and treatment.

The doctor will collect detailed information about your medical history. Be sure to include any medications you take, any history of tumors or cancers that you or family members may have had, and the symptoms you are experiencing.

Your doctor will also perform a physical exam. The focus is on the tumor mass, tenderness in the bone, and any impact on your joints and range of motion. The doctor may want to examine other parts of your body to rule out the spread of any cancer.

Your doctor will probably obtain X-rays for further information. Each type of tumor can exhibit different characteristics on X-ray. Some dissolve bone or make a hole in the bone. Some cause an extra formation of bone. Some can result in a mixture of these findings. In other cases, it may be difficult to tell what kind of tumor is involved and additional imaging studies such as MRI (magnetic resonance imaging) or CT (computed tomography) could be called for.

Insert first three X-ray images from https://health.uconn.edu/msi/clinical-services/orthopaedic-surgery/bone-tumors-and-oncology/benign-and-malignant-bone-tumors/. Figure 1a. 2a. 3.

 

Image Image Image
An X-ray showing a tumor that has caused a saucer-like erosion in the end of the thighbone. A bone tumor in the middle of the femur exhibiting a combination of characteristics is displayed in an X-ray. A fracture through a tumor in the middle of the upper arm bone shown on X-ray.

Your doctor may also request blood and urine tests. If these tests are not adequate to diagnose a tumor, your doctor may request a biopsy. A biopsy is the removal of a sample of tissue from the tumor. The tissue sample is then examined under a microscope. There are two methods for completing a biopsy:

  • Needle Biopsy – A needle is inserted into the tumor to remove a sample of tissue. This may be done under local anesthesia in the doctor's office or it can be done by a radiologist who uses an X-ray machine, CT scanner, or MRI scanner to direct the needle to the tumor.
  • Open Biopsy – The doctor removes tissue in a surgery. This is typically done through a small incision using general anesthesia in an operating room.

Treatment

Treatment of Benign Tumors
In many cases, benign tumors can be closely monitored with no immediate treatment. Some can actually disappear over time. This is particularly true for some benign tumors that occur in children. Other benign tumors can spread or become cancerous (metastasize). They can sometimes be treated effectively with medication or your doctor may recommend removing the tumor. Additional treatment techniques to reduce the risk of fracture and disability may be considered. Some tumors may come back – even repeatedly – after appropriate treatment.

Treatment of Malignant Tumors
If you are diagnosed with malignant bone cancer, your treatment team may include several specialists. It might include an orthopaedic oncologist, a medical oncologist, a radiation oncologist, a radiologist, and a pathologist. Your team of doctors will aim to cure the cancer and preserve the function of your body. Their treatment plan will often combine several methods and depends upon various factors, including whether the cancer is localized or has spread (metastasized). Treatment options include:

  • Limb Salvage Surgery – Removal of the cancerous section of bone, keeping nearby muscles, tendons, nerves, and blood vessels intact. If possible, the surgeon will take out the tumor and a margin of healthy tissue around it. The excised bone is replaced with a metallic implant (prosthesis) or bone transplant.
  • Amputation – Removal of all or part of the arm or leg. Amputation is considered when the tumor is large and/or nerves and blood vessels are involved.
  • Radiation Therapy – High-dose X-rays are used to kill cancer cells and shrink tumors.
  • Systemic Treatment (Chemotherapy) – Often used to kill tumor cells when they have spread into the bloodstream, but cannot yet be detected on tests and scans. Chemotherapy is typically used when cancerous tumors have a high likelihood of spreading.

After Treatment
When treatment for a bone tumor is complete, you may need additional X-rays and other imaging studies to confirm that the tumor is gone. Regular doctor visits and tests may be necessary every few months. When the tumor disappears, it is important to monitor your body for possible relapse.

Research on the Horizon
Genetic research is leading to a better understanding of the types of bone tumors and their behaviors. Researchers are also studying the design of metallic implants to provide better function and durability after limb salvage surgery. Computer technology is also leading to advancements in the development of prosthetic limbs. Research into new medications and new combinations of older medications will lead to continual improvements in survival from bone cancers. Your doctor may discuss clinical research trials with you. Clinical trials may involve the use of new therapies and may offer a better outcome.

Reproduced with permission Fischer S., (interim ed): Your Orthopaedic Connection. Rosemont, Illinois. Copyright American Academy of Orthopaedic Surgeons.