title: Carbohydrate antigen 19-9 producing giant epithelial cyst of the spleen in a young woman.
abstract: We report a giant splenic epithelial cyst which produced carbohydrate antigen 19-9 (CA 19-9) in a 21-year-old woman with left abdominal pain. Imaging techniques revealed a huge cyst of the spleen, and laboratory data revealed elevated serum CA 19-9 (830 U/ml; normal, < 27 U/ml). After splenectomy, serum CA 19-9 level returned to normal. A unilocular splenic cyst measuring 16 x 14 x 13 cm contained brown fluid (900 ml) with a high level of CA 19-9 (10,150,000 U/ml). The wall of the splenic cyst was composed of inner stratified epithelium with mixed squamous and columnar differentiation; immunohistochemical analysis showed that the epithelial cells of the cyst showed strong immunoreactivity to CA 19-9. The inner connective tissue of the cyst wall devoid of epithelial cells was also strongly positive for CA 19-9. We suggest that epithelial cells of our splenic epithelial cyst produced a large amount of CA 19-9 which diffused into capillaries of the connective tissue of the cyst wall and entered into systemic circulation, resulting in the elevated serum CA 19-9.
authors.affiliation: Second Department of Pathology, Kanazawa University School of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Terada
authors.forename: M
authors.initials: M
authors.lastname: Yasoshima
authors.forename: Y
authors.initials: Y
authors.lastname: Yoshimitsu
authors.forename: Y
authors.initials: Y
authors.lastname: Nakanuma
mesh_terms: D000328:Adult; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000097:blood*; D003560:Cysts / Q000276:immunology* / Q000473:pathology; D005260:Female; D006801:Humans; D013158:Splenic Diseases / Q000276:immunology* / Q000473:pathology
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate