title: Use of Truquant BR radioimmunoassay for early detection of breast cancer recurrence in patients with stage II and stage III disease.
abstract: OBJECTIVE
  The Truquant BR radioimmunoassay (RIA) (Biomira Diagnostics Inc, Rexdale, Canada) uses the monoclonal antibody B27.29 to quantitate the MUC-1 gene product (CA 27.29 antigen) in serum. We evaluated CA 27.29 antigen in a controlled, prospective clinical trial for its ability to predict relapse in stage II and stage III breast cancer patients.
  
  
  METHODS
  Over a 2-year period, 166 patients who had completed therapy for stage II (80.1%) or III (19.9%) breast cancer and were clinically free of disease were serially tested for CA 27.29 antigen levels. The study was double-masked and cancer recurrence was documented based on clinical findings. Patients with two consecutive CA 27.29 antigen test results above the upper limit of normal were considered positive.
  
  
  RESULTS
  The Truquant BR RIA had a sensitivity of 57.7%, specificity of 97.9%, positive predictive value of 83.3%, and negative predictive value of 92.6%. The recurrence rate was 15.7%. A Cox regression analysis showed that the only variable to correlate with recurrent disease was the CA 27.29 antigen test result. Patients with a positive test result had increased odds of having a recurrence (odds ratio, 6.8; P < .00001). The test was effective in predicting recurrence in patients with both distant and locoregional disease. In a subgroup of patients with bone pain, CA 27.29 antigen level was found to identify reliably patients who would subsequently develop recurrent disease.
  
  
  CONCLUSIONS
  These data demonstrate that the Truquant BR RIA can be used as an aid to predict recurrent breast cancer in patients with stage II and III disease.
authors.affiliation: Johns Hopkins Medical Institutions, Baltimore, MD 21287-7065, USA. dchan@pathlan.path.jhu.edu
authors.forename: D W
authors.initials: DW
authors.lastname: Chan
authors.forename: R A
authors.initials: RA
authors.lastname: Beveridge
authors.forename: H
authors.initials: H
authors.lastname: Muss
authors.forename: H A
authors.initials: HA
authors.lastname: Fritsche
authors.forename: G
authors.initials: G
authors.lastname: Hortobagyi
authors.forename: R
authors.initials: R
authors.lastname: Theriault
authors.forename: D
authors.initials: D
authors.lastname: Kiang
authors.forename: B J
authors.initials: BJ
authors.lastname: Kennedy
authors.forename: M
authors.initials: M
authors.lastname: Evelegh
mesh_terms: D000328:Adult; D000368:Aged; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000097:blood*; D014408:Biomarkers, Tumor / Q000097:blood*; D001943:Breast Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000601:surgery; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000097:blood / Q000175:diagnosis*; D011863:Radioimmunoassay / Q000379:methods*; D012016:Reference Values; D012044:Regression Analysis; D012680:Sensitivity and Specificity
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate; D014408:Biomarkers, Tumor; C090797:CA 27-29 antigen