[Increased CA-19-9 caused by a splenic cyst: a rare differential diagnosis]

Adenocarcinoma of the gastrointestinal tract, particularly primary adenocarcinoma of the pancreas lead to elevation of serum carbohydrate 19-9 (CA19-9) levels. Some benign disorders, like inflammatory diseases also cause CA19-9 tumor marker elevation. An extremely rare entity are benign splenic cysts which express this tumormarker as reported here.