Lymphoma of the Bone

Lymphoma of the bone or primary lymphoma of bone (PLB) is cancer that starts in the bone rather than the lymph nodes. It appears in the hollow part of bone that contains bone marrow, the soft, spongy tissue that has many blood vessels. PLB is a rare cancer usually found in the thigh and pelvis, accounting for only about 3 percent of all malignant (cancerous) bone tumors.

Types & Stages

The two main types of lymphoma are:

• Hodgkin lymphoma
• Non-Hodgkin lymphoma

Both types of lymphoma are then broken down based on whether the tumors originate in the body's T cells or B cells.

• Most cases of primary lymphoma of bone are a type of non-Hodgkin lymphoma of B cell origin called diffuse large B cell lymphoma (DLBCL). 
   
• The remaining cases are due to a variety of other lymphoma types.

Signs & Symptoms

Symptoms of lymphoma of the bone include:

• Pain, the most common symptom that is felt even at rest
• Swelling or a mass in the area of the tumor
• Fractures in weight-bearing bones like the pelvis, spine or femur (thigh bone)
• Fatigue
• Feeling ill
• Fever
• Night sweats
• Weight loss
• Neurologic symptoms like shooting pain, numbness or tingling in the legs, bowel or bladder incontinence

Diagnosis

Tests and procedures to diagnose lymphoma of the bone include:

• Blood tests. Your doctors will likely order blood tests to check for any abnormalities (levels that are outside of normal ranges) in your blood count, electrolytes, inflammation, hormone levels and cancer markers. They may also check for abnormalities in the types and numbers of different cells within your blood to look for signs of anemia (low red blood cell count) and thrombocytopenia (low platelet count).
   
• Imaging tests. These may include:   
   
  • X-rays. An X-ray of PLB could reveal a mottled (moth-eaten) appearance in the inner part of the bone, erosion (small craters or holes) of the bone, a soft tissue mass or swelling or a change in the normal shape of the bone due to tumor expansion.
     
  • Computerized tomography scan (CT or CAT scan). A diagnostic imaging procedure that uses a combination of X-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. 
     
  • Magnetic resonance imaging (MRI). A diagnostic procedure that uses a combination of large magnets, radiofrequencies and a computer to produce detailed images of organs and structures within the body. 
     
  • Positron emission tomography scan (PET scan). An imaging test that uses a radioactive drug called a tracer—most often injected into a vein in your hand or arm—to show both typical and atypical metabolic activity. The PET images are typically combined with CT or MRI and are called PET-CT or PET-MRI scans.
     
  • Biopsy. A definitive (final) diagnosis of primary lymphoma of bone is made with a procedure called a bone biopsy. In a bone biopsy, a small sample of the tumor is removed and examined under a microscope by an orthopaedic surgeon or an interventional radiologist.

Treatment

In most cases, treatment for lymphoma of the bone involves:  

• Chemotherapy. Treatment for PLB almost always includes some combination of multi-agent chemotherapy either with or without radiation.  
   
• Radiation. Radiation therapy is commonly used to help destroy tumor cells in primary lymphoma of bone. Radiation therapy uses high dose X-ray to kill cancer cells in the bone and help the bone heal. A radiation oncologist manages detailed plans to kill lymphoma cells in a targeted way that helps to preserve normal, healthy cells.
   
• Surgery. Surgery to remove the tumor is generally not performed in primary lymphoma of the bone. However, some patients may need surgery to stabilize the affected bone (make it secure) in cases where there is a pathologic fracture or an impending pathologic fracture (meaning it will likely happen in the near future). PLB can cause significant pain and immobility; surgery to stabilize the bone can often help decrease pain and improve mobility. During the procedure, your surgeon inserts metal rods or plates and screws to either fix an existing fracture or prevent bone breakage before it occurs.  

Causes & Risk Factors

The cause of lymphoma of the bone is not fully understood by doctors, but risks can include:

• Age. While it can occur at any age, PLB is more common in people over 30.
   
• Gender. Men are affected more frequently than women.
   
• Family history. A family history of lymphoma may increase your risk.
   
• Autoimmune diseases. Certain autoimmune diseases such as rheumatoid arthritis and lupus may increase the risk of lymphoma. 
   
• Weakened immune system. Patients who are infected with certain viruses (HIV and Epstein-Barr) and those who have had an organ transplant are at increased risk for developing the condition.

Screening 

There is no standardized screening for lymphoma of the bone.