Falsely elevated serum oestradiol due to exemestane therapy.
In this study, we present a case of falsely elevated oestradiol (E2) concentration, determined by two immunoassays, in a breast cancer patient receiving exemestane therapy. The positive bias of immunochemical measurements was revealed using liquid chromatography tandem mass spectrometry which showed undetectable E2concentration. The discrepancy is expected to be a consequence of the structural resemblance of E2and exemestane sharing the same steroidal backbone. Inaccurate laboratory findings in therapy monitoring, as in this case, may lead to unnecessary changes of therapy.
1 Institute of Clinical Laboratory Diagnostics, Osijek University Hospital, Osijek, Croatia.|2 Department for Chemistry, Biochemistry and Clinical Chemistry, Faculty of Medicine, University of Osijek, Osijek, Croatia.
Sanja
S
Mandic
3 Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Clinic Leipzig-AÖR, Leipzig, Germany.
Jϋrgen
J
Kratzsch
1 Institute of Clinical Laboratory Diagnostics, Osijek University Hospital, Osijek, Croatia.|2 Department for Chemistry, Biochemistry and Clinical Chemistry, Faculty of Medicine, University of Osijek, Osijek, Croatia.
Dario
D
Mandic
1 Institute of Clinical Laboratory Diagnostics, Osijek University Hospital, Osijek, Croatia.|4 Department of Pharmacology, Faculty of Medicine, University of Osijek, Osijek, Croatia.
Zeljko
Z
Debeljak
1 Institute of Clinical Laboratory Diagnostics, Osijek University Hospital, Osijek, Croatia.|2 Department for Chemistry, Biochemistry and Clinical Chemistry, Faculty of Medicine, University of Osijek, Osijek, Croatia.
Iva
I
Lukic
1 Institute of Clinical Laboratory Diagnostics, Osijek University Hospital, Osijek, Croatia.|2 Department for Chemistry, Biochemistry and Clinical Chemistry, Faculty of Medicine, University of Osijek, Osijek, Croatia.
Vesna
V
Horvat
3 Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Clinic Leipzig-AÖR, Leipzig, Germany.
Alexander
A
Gaudl
1 Institute of Clinical Laboratory Diagnostics, Osijek University Hospital, Osijek, Croatia.|2 Department for Chemistry, Biochemistry and Clinical Chemistry, Faculty of Medicine, University of Osijek, Osijek, Croatia.
Vatroslav
V
Seric
D000730:Androstadienes / Q000097:blood* / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000097:blood* / Q000627:therapeutic use; D047072:Aromatase Inhibitors / Q000097:blood* / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D000075202:Contraindications; D054796:Drug Dosage Calculations; D004958:Estradiol / Q000097:blood*; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D007118:Immunoassay; D008875:Middle Aged; D018716:Molecular Mimicry; D008991:Monitoring, Physiologic
D000730:Androstadienes; D000970:Antineoplastic Agents; D047072:Aromatase Inhibitors; D004958:Estradiol; C056516:exemestane
Immunoassay; mass spectrometry; steroid hormones