title: Immunohistological analysis of stress-induced phosphoprotein 1 in ovarian cancer patients with low serum cancer antigen 125 levels.
abstract: OBJECTIVE
  Stress-induced phosphoprotein 1 (STIP1) was recently identified as a potential tumor marker for human ovarian cancer. This study further evaluates the usefulness of STIP1 in ovarian tumor patients with normal CA125 serum levels.
  
  
  METHODS
  STIP1 and CA125 were immunohistochemically analyzed in 84 primary ovarian cancer and 30 benign ovarian tumors in patients with serum CA125 levels < 35 U/mL before surgery. Histoscores (0-300) were calculated as staining intensities (0-3) multiplied by percentage of tumor tissue (0-100%).
  
  
  RESULTS
  The cell types of the 84 cancers included 11 serous, 10 clear-cell, 51 mucinous, and 12 endometrioid carcinomas. There were 55 patients with invasive cancer and 29 with borderline ovarian tumors. The histoscores of STIP1, but not of CA125, in invasive cancer (mean ± SD, 186.3 ± 82.5) were significantly (p < 0.0001) higher than those seen in borderline ovarian tumors (86.2 ± 85.5). When the STIP1 histoscore was set at 183.8, invasive cancers (n = 55) were identified from benign tumors (n = 30) with a sensitivity of 56.4%, a specificity of 93.3%, a positive predictive value of 93.9%, and a negative predictive value of 53.8%. Results of receiver operating characteristics analysis showed that the area under curve of the STIP1 histoscore was 0.755, which was superior to that of CA125 (0.599).
  
  
  CONCLUSIONS
  STIP1 histoscores may be useful in detecting invasive human ovarian cancer in patients with low serum CA125 levels.
authors.affiliation: Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Angel
authors.initials: A
authors.lastname: Chao
authors.forename: Li-Yu
authors.initials: LY
authors.lastname: Lee
authors.forename: Chuen
authors.initials: C
authors.lastname: Hsueh
authors.forename: Chiao-Yun
authors.initials: CY
authors.lastname: Lin
authors.forename: Chia-Lung
authors.initials: CL
authors.lastname: Tsai
authors.forename: An-Shine
authors.initials: AS
authors.lastname: Chao
authors.forename: Chen-Tao
authors.initials: CT
authors.lastname: Lin
authors.forename: Hung-Hsueh
authors.initials: HH
authors.lastname: Chou
authors.forename: Ting-Chang
authors.initials: TC
authors.lastname: Chang
authors.forename: Tzu-Hao
authors.initials: TH
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D018394:CA-125 Antigen / Q000097:blood* / Q000378:metabolism; D005260:Female; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008565:Membrane Proteins / Q000097:blood* / Q000378:metabolism; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009369:Neoplasms / Q000378:metabolism / Q000473:pathology; D010051:Ovarian Neoplasms / Q000378:metabolism* / Q000473:pathology*; D010053:Ovary / Q000378:metabolism / Q000473:pathology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D018394:CA-125 Antigen; D006360:Heat-Shock Proteins; C451759:MUC16 protein, human; D008565:Membrane Proteins; C079373:STIP1 protein, human
keywords: borderline tumor; cancer antigen 125; carcinoma; ovary; stress-induced phosphoprotein 1