Background: Recently, several cases of nonparasitic true splenic cyst with high serum concentration of carbohydrate antigen (CA 19-9) have been reported.
Case: We report a giant splenic cyst presenting with high serum concentration of CA 19-9 in a 21-year-old man without a history of previous trauma. Imaging techniques showed a huge monolocular cyst of the spleen, and laboratory data showed increased serum CA 19-9 levels (326 U/ml; normal, < 37 U/ml). Serologic test was negative for parasitic infection. These findings led us to the diagnosis of epithelial splenic cyst. Percutaneous transcatheter drainage and injection of tetracycline were performed for 2 weeks. The cyst shrank, and the serum CA 19-9 level decreased favorably. However, cystic fluid reaccumulated in a month.
Conclusions: The accumulation of cystic fluid in splenic epithelial cysts may be attributable not only to the secretion of the lining cells but also to influx from the splenic sinuses.