A Tale of Two Cysts: A Histopathological Case Report of Epithelial and Mesothelial Splenic Cysts

Splenic cysts are rare medical conditions, and their incidence is dominated by parasitic types. Non-parasitic splenic cysts, whether true cysts (with a cellular lining of the cystic wall) or pseudocysts (without a cellular lining), are significantly rarer than parasitic ones. Their etiology is not fully established, with fetal remnant development, metaplasia, and mesothelial invagination being widely accepted possible mechanisms. Splenic cysts are rarely symptomatic if small and are predominantly discovered incidentally, while larger and multiple splenic cysts mainly present with dull abdominal pain or discomfort. Herein, we report two cases of splenic cysts. The first case involves a 14-year-old female with an insignificant medical history, presenting with dull abdominal pain developing over the previous month. Computed tomography (CT) revealed a cystic lesion within the lower aspect of the spleen, measuring 150 × 130 × 115 mm, with compression of the left kidney. The patient was treated with partial splenectomy, and histopathology revealed a true epithelial cyst. The second case involves a 45-year-old male, also without significant prior medical history, presenting with subacute abdominal pain. Abdominal CT showed multiple splenic cysts, the largest measuring 50 mm, and multiple dispersed smaller ones measuring between 4 and 8 mm, with compression of the left kidney. The patient was treated with total splenectomy, and histopathology showed multiple mesothelial splenic cysts.