Primary Bone Lymphoma

Primary Bone Lymphoma

Prepared by Dr. Ali Erkan YENIGUL

A rare lymphoma subtype presenting primarily in bone, often mimicking other primary bone tumours.

Epidemiology

• Accounts for 3–7% of all primary malignant bone tumors.
• About 5% of extranodal lymphomas, but <1% of all Non-Hodgkin lymphomas (NHL).
• Predominantly affects 20–50 years, with male preponderance.
• Femur most common site (~29%), followed by tibia, pelvis, and spine.
• Rare presentations: solitary lesions in the skull.

Etiology

• Mostly non-Hodgkin B-cell lymphomas (DLBCL commonest).
• Rarely T-cell variants.
• Genetic predisposition and viral infections (EBV) implicated.
• Classified as:
  Solitary bone site
  Multiple bone sites
  Bone + soft tissue lymphoma

Clinical Presentation

• Bone pain unrelieved by rest (most common).
• ~25% present with pathological fracture.
• Neurological symptoms if spine involved.
• Systemic symptoms: fever, weight loss, night sweats.

  Imaging

• X-ray: variable → from near-normal to lytic, mixed lytic-sclerotic, or permeative lesions ± soft tissue mass.
• MRI, PET-CT, CT: essential for marrow infiltration, extraosseous spread, treatment response.
• Differential diagnosis: osteomyelitis, multiple myeloma, metastasis.

 Pathology

• Diagnosis: biopsy + bone marrow aspiration.
• Histology:
  Diffuse large B-cell lymphoma (DLBCL) most frequent.
  IHC: CD20+, CD45+, LCA+.
  “Small round blue cell” infiltration possible.

Treatment

• Multidisciplinary approach: systemic chemotherapy + local radiotherapy.
• CHOP-like regimens (anthracyclines, cyclophosphamide) = mainstay.
• Chemotherapy alone effective for most lesions.
• Surgery: reserved for pathological fracture fixation or stabilization.

 References

1. Beal K, Allen L, Yahalom J. Primary bone lymphoma: treatment results and prognostic factors with long-term follow-up of 82 patients. Cancer. 2006;106(12):2652-6.
2. Jawad MU, Schneiderbauer MM, Min ES, Cheung MC, Koniaris LG, Scully SP. Primary lymphoma of bone in adult patients. Cancer. 2010;116(4):871-9.
3. Messina C, Christie D, Zucca E, Gospodarowicz M, Ferreri AJM. Primary and secondary bone lymphomas. Cancer Treat Rev. 2015;41(3):235-46.
4. Ramadan KM, Shenkier T, Sehn LH, Gascoyne RD, Connors JM. A clinicopathological retrospective study of 131 patients with primary bone lymphoma: a population-based study of successively treated cohorts from the British Columbia Cancer Agency. Ann Oncol. 2007;18(1):129-35.
5. Fletcher CDM, Bridge JA, Hogendoorn P, Mertens F, eds. WHO Classification of Tumours of Soft Tissue and Bone. 5th ed. Lyon: IARC Press; 2020.