title: Increased serum CA125 levels in plasma cell dyscrasias.
abstract: We report 2 cases of plasma cell dyscrasia presenting with significantly elevated serum CA125 levels. The serum levels of CA125 from these patients correlated well with their serum M-protein levels. One patient had an IgG-kappa type extramedullary plasmacytoma with the culture supernatant from lymph node plasma cells showing a considerably high level of CA125 activity. The serum IgG fraction purified using a protein A column was devoid of any detectable CA125 activity, negating that the serum IgG M-protein from this patient might respond with a false-positive result in the CA125 immunoradiometric assay. The other patient had an IgG-lambda type plasma cell leukemia with the culture supernatant from peripheral mononuclear cells also showing a high level of CA125 activity. These observations may suggest that in plasma cell dyscrasias the CA125 antigen is spontaneously produced by tumor cells.
authors.affiliation: Second Department of Internal Medicine, Hyogo College of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Iwasaki
authors.forename: T
authors.initials: T
authors.lastname: Hamano
authors.forename: K
authors.initials: K
authors.lastname: Aizawa
authors.forename: K
authors.initials: K
authors.lastname: Kobayashi
authors.forename: E
authors.initials: E
authors.lastname: Kakishita
mesh_terms: D000368:Aged; D018394:CA-125 Antigen / Q000097:blood*; D002478:Cells, Cultured; D064211:Connectin; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007952:Leukemia, Plasma Cell / Q000097:blood / Q000150:complications; D008198:Lymph Nodes / Q000737:chemistry; D008297:Male; D008875:Middle Aged; D009124:Muscle Proteins; D009194:Myeloma Proteins / Q000032:analysis; D010265:Paraproteinemias / Q000097:blood* / Q000150:complications; D010954:Plasmacytoma / Q000097:blood / Q000150:complications
chemical_list: D018394:CA-125 Antigen; D064211:Connectin; D007074:Immunoglobulin G; D009124:Muscle Proteins; D009194:Myeloma Proteins; C085016:multiple myeloma M-proteins