Benign Focal Lesions of the Spleen

Abstract

Benign focal lesions of the spleen can be categorized into benign tumor, cystic lesion, and infectious lesion. The most common benign tumor of the spleen is hemangioma, followed by hamartoma and lymphangioma. They often present as single lesions, but infrequently multiple lesions such as hemangiomatosis or lymphangiomatosis can be detected. They are usually found incidentally during imaging evaluation for various reasons because they usually do not make symptoms or clinically relevant signs. However, they infrequently cause symptoms by compressing adjacent organs, due to associated changes of splenic function such as anemia or thrombocytopenia, and also they rarely need emergent interventional or surgical intervention due to hemorrhage or rupture. Littoral cell angioma and sclerosing angiomatoid nodular transformation are recently defined benign spleen-specific disease entities. Although they can be presented with typical imaging findings, it is not easy to correctly diagnose because of its low incidence. Pseudocyst consists of approximately 90 % of non-parasite-related splenic cystic lesions. Epidermoid cyst which is a true cyst of congenital origin accounts for the rest of nonparasitic splenic cystic lesions. Echinococcal cyst may present with typical imaging findings, but it is rare outside the endemic area of echinococcus infection. Infectious disease can be accompanied with clinical symptoms such as fever, and medical history of the patient may be helpful for differentiating them from tumorous lesions.