Primary Bone Diffuse Large B-cell Lymphoma

Lymphoma confined to the bone at the time of diagnosis with the morphology and immunophenotype of diffuse large B-cell lymphoma.

Definition

These tumours occur across a wide age range with a median of 60 years and a slight male predominance. Any bone may be involved, most commonly the femur.

Epidemiology

Primary bone lymphoma accounts for less than 1% of all lymphomas and for 7% of malignant bone tumours. Most are diffuse large B-cell lymphomas.

Clinical features

Patients most commonly present with bone pain.

Histopathology

The tumour shows a diffuse growth pattern, comprising sheets either of large atypical cells or a polymorphous population of small and large cells

Immunohistochemistry

	CD20	21/211
	CD10	8/211
	bcl-2	17/211
	bcl-6	10/211
	MUM1	14/211
	p53	11/211
	germinal centre B-cell type	9/211
	MIB1	mean 57%1

	bcl-6 gene rearrangement by FISH	3/211
	IGH / bcl-2 gene rearrangement by FISH	4/211
	c-myc gene rearrangement by FISH	2/211
	IGH gene rearrangement by PCR	10/171
	IGH/bcl-2 gene rearrangement by PCR	4/171

Management

Chemotherapy.

Prognosis

Age less than 60 years and complete response to initial treatment are associated with a favourable prognosis.

References

1 S Bhagavath et al. Primary Bone Diffuse Large B-cell Lymphoma: Clinicopathologic Study of 21 Cases and Review of Literature. Am J Surg Pathol 2009;33:1463–1469