Primary lymphoma of the bone: Difference between revisions
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*Early clinical features include bone pain, or palpable mass. | *Early clinical features include bone pain, or palpable mass. | ||
*If left untreated, patients with primary lymphoma of the bone may progress to develop metastasis. | *If left untreated, patients with primary lymphoma of the bone may progress to develop metastasis. | ||
*The most common complication of primary lymphoma of the bone is a pathological fracture | *The most common complication of primary lymphoma of the bone is a pathological fracture. | ||
*Prognosis is generally good, and the 5-year survival rate of patients with primary lymphoma of the bone is approximately > 80%. | *Prognosis is generally good, and the 5-year survival rate of patients with primary lymphoma of the bone is approximately > 80%. | ||
Revision as of 12:57, 3 May 2016
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: John Fani Srour, M.D. Maria Fernanda Villarreal, M.D. [2]
Synonyms and keywords: PLB
Overview
Primary lymphoma of the bone (also known as "PLB" ) is an uncommon malignancy that accounts for less than 5% of all primary bone tumors. The majority of cases are of the non-Hodgkin type, with Hodgkin disease accounting for only 6% of cases. Primary lymphoma of the bone was first discovered by Ostrowski in 1986. The pathogenesis of primary lymphoma of the bone is characterized by an excessive osteoclast activation. Primary lymphoma of the bone is commonly located in bone marrow, axial skeleton, or femur (most common). Primary lymphoma of the bone may be classified according to location into 4 groups: solitary, multifocal, distant, and visceral. The mutation in BCL2 and BCL6, has been associated with the development of primary lymphoma of the bone. Primary lymphoma of the bone is rare. The prevalence of primary lymphoma of the bone is approximately 0.01 per 100,000 individuals worldwide. Primary lymphoma of the bone is more commonly observed among middle aged adults and elderly patients. MRI is the imaging modality of choice for primary lymphoma of the bone. The mainstay of therapy for primary lymphoma of the bone is chemotherapy.
Historical Perspective
- Primary lymphoma of the bone was first discovered by Ostrowski in 1986.
Classification
- Primary lymphoma of the bone may be classified according to location into 4 groups:
- PBL 1: solitary bone lymphoma
- PBL 2: multifocal bony lesions
- PBL 3: cases with distant nodal disease
- PBL 4: cases with visceral disease
Pathophysiology
- The pathogenesis of primary lymphoma of the bone is characterized by
- Excessive osteoclast activation
- Commonly located in bone marrow, axial skeleton, or femur
- The femur is the most common site of affection
- The most common site affected is the metaphysis
- The mutation in BCL2 and BCL6, has been associated with the development of primary lymphoma of the bone.
- On gross pathology, characteristic findings of primary lymphoma of the bone, include:
- Fish flesh appearance of lymphoma
- Extraosseous extension and indistinct margins
- On microscopic histopathological analysis, characteristic findings of primary lymphoma of the bone, include:
Causes
- There are no established causes for primary lymphoma of the bone.
Differentiating Primary Lymphoma of the Bone from Other Diseases
- Primary lymphoma of the bone must be differentiated from other diseases that cause bone pain, fever, and limited range of motion, such as:
- Osteosarcoma
- Bone metastasis
- Spindle cell sarcoma
- Myeloid sarcoma
Epidemiology and Demographics
- Primary lymphoma of the bone accounts for less than 5% of all primary bone tumors.
- The prevalence of primary lymphoma of the bone is approximately 0.01 per 100,000 individuals worldwide.
Age
- Primary lymphoma of the bone is more commonly observed among patients aged 50 to 70 years old.
- Primary lymphoma of the bone is more commonly observed among middle aged adults and elderly patients.
Gender
- Primary lymphoma of the bone affects men more frequently than women.
Race
- There is no racial predilection for primary lymphoma of the bone.
Risk Factors
- The most common risk factors in the development of primary lymphoma of the bone is previous exposure to radiation.
Natural History, Complications and Prognosis
- The majority of patients with primary lymphoma of the bone are symptomatic at the time of diagnosis.
- Early clinical features include bone pain, or palpable mass.
- If left untreated, patients with primary lymphoma of the bone may progress to develop metastasis.
- The most common complication of primary lymphoma of the bone is a pathological fracture.
- Prognosis is generally good, and the 5-year survival rate of patients with primary lymphoma of the bone is approximately > 80%.
Diagnosis
Symptoms
- Symptoms of primary lymphoma of the bone may include the following:
- Bone pain
- Limited range of motion
- Morning stiffness
- Low grade fever
- Night sweating
Physical Examination
- Patients with primary lymphoma of the bone usually appear pale or malnourished.
- Physical examination may be remarkable for:
- Swelling
- Limited range of motion
- Gait disturbances
- Palpable mass
Laboratory Findings
- There are no specific laboratory findings associated with primary lymphoma of the bone.
- In some cases, findings may include:
- Elevated LDH
- Elevated B2 microglobulin
Imaging Findings
- MRI is the imaging modality of choice for primary lymphoma of the bone.
- On conventional radiograph, findings of primary lymphoma of the bone, include:
- Non-specific features
- Affected bone may be normal or affected by lytic, sclerotic or mixed pattern.
- The most common is a lytic pattern with permeative bone destruction and a wide zone of transition
- On MRI, findings of primary lymphoma of the bone, include:
- Abnormalities in bone marrow
Treatment
Medical Therapy
- The mainstay of therapy for primary lymphoma of the bone is chemotherapy.
- Response to chemotherapy or radiotherapy can be monitored with imaging findings.
Surgery
- Surgery is not recommended among patients with primary lymphoma of the bone.
Prevention
- There are no primary preventive measures available for primary lymphoma of the bone.