Clinical features:
(1) The metastasis may be solitary or multiple.
(2) The metastasis may appear years after the primary tumor was diagnosed.
(3) The metastasis to the spleen may be the only metastasis or part of a disseminated disease.
Location of splenic metastases:
(1) within the splenic parenchyma via hematogenous spread
(2) subcapsular foci from peritoneal dissemination
Tumors that can spread to the spleen via the blood include:
(1) colon
(2) ovary
(3) breast
(4) lung
(5) melanoma
(6) malignant lymphoma
Patterns of intraparenchymal tumors:
(1) large tumors (macronodules)
(2) small tumors (micronodular)
(3) diffuse infiltration
(4) microscopic in sinuses or blood vessels
Differential diagnosis:
(1) primary tumor or cyst of the spleen
(2) granulomatous infection
(3) parasitic infection
Splenectomy is usually not necessary to establish the diagnosis. A needle aspirate can often establish the diagnosis safely.
