Spontaneously Ruptured Giant Splenic Cyst with Elevated Serum Levels of CA 19-9, CA 125 and Carcinoembryonic Antigen.

Splenic cyst is a relatively rare disease; however, the occurrence of complications associated with its rupture is even more rare. A 20-year-old female patient who had severe abdominal and left shoulder pain was admitted to our hospital. The patient's abdomen was hard and tender to the touch and she presented with a high fever. The patient's serum levels of the tumor markers carbohydrate antigen 19-9, cancer antigen 125 and carcinoembryonic antigen were high. Ultrasonography and computed tomography of the abdomen showed an 11-cm multilocular cystic lesion in the spleen and the presence of free intraperitoneal fluid. Peritonitis with ruptured splenic cyst was diagnosed, and the patient underwent an emergency laparotomy. The abdominal cavity was filled with purulent fluid. The cyst was localized to the spleen and had already ruptured. Total splenectomy and cyst resection were performed. The postoperative course was uneventful. The patient was discharged on day 9 following surgery. The histological findings showed the lesion to be a benign epidermoid cyst completely lined with inner stratified squamous epithelium with a capsule of connective tissue. In the immunostaining analyses, the squamous epithelium was positive for carcinoembryonic antigen. A ruptured splenic cyst causes sudden onset of severe peritonitis and elevation of serous tumor markers. An emergency operation is indicated as the treatment for a ruptured splenic cyst with peritonitis, after which a favorable outcome can be expected.