Follicular lymphoma of the testis

Definition

Epidemiology

Primary testicular lymphomas account for about 1% of all lymphomas and up to 5% of all testicular tumours. Up to 90% of testicular lymphomas are diffuse large B-cell lymphomas of non-germinal centre type: they occur predominantly in men over 60 years of age. Primary follicular lymphoma of the testis is rare; it occurs predominantly in boys and young adult men.

Clinical features

Presentation is with unilateral testicular enlargement.

Macroscopic appearances

The tumour is firm, white to tan. There may be epididymal involvement.

Histopathology

The lymphomatous infiltrate may permeate or replace the testicular and epididymal structures. The architecture varies form vaguely nodular to well formed small neoplastic follicles. There may be foci of diffuse large B-cell lymphoma.

Immunohistochemistry

Note that the neoplastic cells are negative for bcl-2, corresponding to the lack of a t(14;18) translocation.

	CD20	4/41
	CD10	4/41, 5/81
	CD21	stains dendritic follicular cells within the neoplastic follicles1
	bcl-2	0/4, 0/111
	bcl-6	4/4, 8/91
	p53	1/4(weak)1 , 0/71
	Ki-67	expressed by 40% to 80% of cells1
	t(14;18) / IGH-bcl2 gene rearrangement by FISH and PCR	0/41, 0/81

Differential diagnosis

Diffuse large B-cell lymphoma

Management

Orchidectomy and chemotherapy.

Prognosis

With chemotherapy, the prognosis appears good. There does not appear to be the propensity to widespread, including CNS, spread seen in testicular diffuse large B-cell lymphoma.

References

1 Bacon CM, Ye H, Diss TC, et al. Primary follicular lymphoma of the testis and epididymis in adults. Am J Surg Pathol 2007; 31:1050-8

This page last revised 11.11.2007.