[Splenic hamartoma]

The Authors present a case of Splenic Hamartoma. This is a rare unique complex vascular lesion of the spleen. This is also a recently reinterpreted lesion with some persistent confusion regarding its definition, histogenesis and classification. The patient is a young woman who following a check up with a raised erythrocyte sedimentation rate underwent abdominal sonography demonstrating an incidental slightly hypoechoic nodular splenic lesion. The pathologic study of the splenectomy specimen showed a large (10 cm) sharply demarcated mass. Histologically the lesion presented a remarkably angiomatoid lobular-nodular configuration with abundant fibrosclerotic stroma with areas of calcification. The immunohistochemical study revealed within the angiomatoid tissue different types of blood vessels: a) capillaries CD31+, CD34+, CD8-; b) structures consistent with splenic venous sinuses CD31+, CD34+/- , CD8-/+; c) small veins CD31+, CD34+, CD8-. The Authors judge this complex picture as indicative of a Splenic Hamartoma with a peculiar lobular-nodular pattern that seems to coincide with the recently described SANT: Sclerosing Angiomatoid Nodular Transformation of the spleen. In this report the Authors discuss the pathology of the lesion and the problems concerning its vasular profile. It is also emphasized the Hamartoma's great variety of morphologic patterns derived from the preponderant growth of one or another of several histologic components. This is the cause of the presence in literature of some different pathologic entities which today are fairly recognized as part of a large pathologic spectrum of the same lesion. The Authors discuss the differential diagnosis of Splenic Hamartoma with other lesions as haemangiomas and inflammatory pseudotumor.