title: False-positive human serum chorionic gonadotropin in a patient with a history of germ cell cancer.
abstract: Tumor markers, including the beta-subunit of human chorionic gonadotropin (beta-hCG), and radiological imaging methods are commonly used for the diagnosis and monitoring of testicular cancer. We report of a patient with a history of classical seminoma stage I who had elevated serum levels of beta-hCG suggesting relapse 5 years after initial treatment. Radiological evaluation revealed a pericardial cyst, which was surgically removed. Histological evaluation did not demonstrate malignant tissue, suggesting a false-positive beta-hCG. Further workup confirmed this suspicion as we could demonstrate false-positive test results due to heterophilic antibodies detectable in the patient's serum. This case stresses the need for verification of beta-hCG levels in patients where clinical results are not in line with laboratory results.
authors.affiliation: Clinic and Policlinic of Oncology, University Hospital Zurich, Zurich, Switzerland. andreas.trojan@usz.ch
authors.forename: Andreas
authors.initials: A
authors.lastname: Trojan
authors.forename: Helen
authors.initials: H
authors.lastname: Joller-Jemelka
authors.forename: Rolf A
authors.initials: RA
authors.lastname: Stahel
authors.forename: Emanuel
authors.initials: E
authors.lastname: Jacky
authors.forename: Martin
authors.initials: M
authors.lastname: Hersberger
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000097:blood*; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood*; D003937:Diagnosis, Differential; D005189:False Positive Reactions; D018237:Germinoma / Q000097:blood* / Q000175:diagnosis; D006801:Humans; D008297:Male; D008476:Mediastinal Cyst / Q000097:blood / Q000175:diagnosis* / Q000601:surgery; D013736:Testicular Neoplasms / Q000097:blood* / Q000175:diagnosis
chemical_list: D014408:Biomarkers, Tumor; D018997:Chorionic Gonadotropin, beta Subunit, Human