Giant Splenic Hamartoma Associated With Hematological Symptoms: A Case Report and Literature Review

Splenic hamartoma is a low-incidence, benign primary vascular neoplasm of the spleen of unknown origin. It is usually asymptomatic and diagnosed incidentally or during an autopsy. However, large tumors can cause hematologic symptoms secondary to splenic sequestration, including anemia and thrombocytopenia. We report the case of a 65-year-old man with mild chest pain, exertional dyspnea and asthenia, associated with thrombocytopenia and hepatosplenomegaly. A splenic mass was detected by ultrasound and magnetic resonance imaging, whose differential diagnoses included hematolymphoid neoplasia, hamartoma, angioma, and angiosarcoma. Microscopic examination revealed a mass composed of scattered vascular channels delineated by a reactive endothelium and aggregates of tissue macrophages, accompanied by extramedullary haematopoiesis. Immunohistochemical studies revealed the presence of CD34+, CD31+, and CD8- capillary sinusoids intermingled with CD8+, CD31+, and CD34- splenic sinusoids; abundant CD68+ macrophages and scattered B and T lymphocytes, characteristics that confirmed the diagnosis of splenic hamartoma. Due to its unusual presentation and large tumor size, this case represents an example of how a comprehensive understanding of the differential diagnoses of primary splenic tumors is crucial for pathologists in order to avoid diagnostic confusion and secure a correct treatment for the patients.