Juan Morote1, Inma Comas2, Jacques Planas1, Xavier Maldonado3, Ana Celma3, José Placer3, Roser Ferrer2, Joan Carles4, Lucas Regis5. 1. Department of Urology, Vall d'Hebron Hospital, Universitat Autònoma de Barcelona, Barcelona, Spain. 2. Department of Biochemistry, Vall d'Hebron Hospital, Universitat Autònoma de Barcelona, Barcelona, Spain. 3. Department of Radiation Oncology, Vall d'Hebron Hospital, Universitat Autònoma de Barcelona, Barcelona, Spain. 4. Department of Medical Oncology, Vall d'Hebron Hospital, Universitat Autònoma de Barcelona, Barcelona, Spain. 5. Department of Urology, Vall d'Hebron Hospital, Universitat Autònoma de Barcelona, Barcelona, Spain. Electronic address: lregis@vhebron.net.
Abstract
BACKGROUND: Serum testosterone measurement is recommended to assess the efficacy of androgen deprivation therapy (ADT) and to diagnose castration resistance in patients with prostate cancer (PCa). Currently, the accepted castrate level of serum testosterone is 50 ng/dL. Liquid chromatography and tandem mass spectrometry (LC MSMS) is the appropriate method to measure testosterone, especially at low levels. However, worldwide, chemiluminescent assays (CLIAs) are used in clinical laboratories, despite their lack of accuracy and reproducibility, because they are automatable, fast, sensitive, and inexpensive. MATERIALS AND METHODS: We compared serum testosterone levels measured using LC MSMS and CLIAs in 126 patients with PCa undergoing luteinizing hormone-releasing hormone (LHRH) agonist therapy. RESULTS: The median serum testosterone level was 14.0 ng/dL (range, 2.0-67.0 ng/dL) with LC MSMS and 31.9 ng/dL (range, 10.0-91.6 ng/dL) with CLIA (P < .001). The serum testosterone levels, measured using LC MSMS, were < 20 ng/dL in 83 patients (65.9%), 20 to 50 ng/dL in 40 (31.7%), and > 50 ng/dL in 3 patients (2.4%). These ranges were found in 34 (27%), 72 (57.1%), and 20 (15.9%) patients when testosterone was measured using CLIA (P < .001). The castrate level of serum testosterone using LC MSMS and CLIA was 39.8 ng/dL (95% confidence interval [CI], 37.1-43.4 ng/dL) and 66.5 ng/dL (95% CI, 62.3-71.2 ng/dL), respectively. CONCLUSION: We found that CLIA overestimated the testosterone levels in PCa patients undergoing LHRH agonist therapy. Thus, the castration level was incorrectly considered inadequate with CLIA in almost 15% of patients. The true castration level of serum testosterone using an appropriate method is < 50 ng/dL.
BACKGROUND: Serum testosterone measurement is recommended to assess the efficacy of androgen deprivation therapy (ADT) and to diagnose castration resistance in patients with prostate cancer (PCa). Currently, the accepted castrate level of serum testosterone is 50 ng/dL. Liquid chromatography and tandem mass spectrometry (LC MSMS) is the appropriate method to measure testosterone, especially at low levels. However, worldwide, chemiluminescent assays (CLIAs) are used in clinical laboratories, despite their lack of accuracy and reproducibility, because they are automatable, fast, sensitive, and inexpensive. MATERIALS AND METHODS: We compared serum testosterone levels measured using LC MSMS and CLIAs in 126 patients with PCa undergoing luteinizing hormone-releasing hormone (LHRH) agonist therapy. RESULTS: The median serum testosterone level was 14.0 ng/dL (range, 2.0-67.0 ng/dL) with LC MSMS and 31.9 ng/dL (range, 10.0-91.6 ng/dL) with CLIA (P < .001). The serum testosterone levels, measured using LC MSMS, were < 20 ng/dL in 83 patients (65.9%), 20 to 50 ng/dL in 40 (31.7%), and > 50 ng/dL in 3 patients (2.4%). These ranges were found in 34 (27%), 72 (57.1%), and 20 (15.9%) patients when testosterone was measured using CLIA (P < .001). The castrate level of serum testosterone using LC MSMS and CLIA was 39.8 ng/dL (95% confidence interval [CI], 37.1-43.4 ng/dL) and 66.5 ng/dL (95% CI, 62.3-71.2 ng/dL), respectively. CONCLUSION: We found that CLIA overestimated the testosterone levels in PCa patients undergoing LHRH agonist therapy. Thus, the castration level was incorrectly considered inadequate with CLIA in almost 15% of patients. The true castration level of serum testosterone using an appropriate method is < 50 ng/dL.
Authors: E David Crawford; Axel Heidenreich; Nathan Lawrentschuk; Bertrand Tombal; Antonio C L Pompeo; Arturo Mendoza-Valdes; Kurt Miller; Frans M J Debruyne; Laurence Klotz Journal: Prostate Cancer Prostatic Dis Date: 2018-08-21 Impact factor: 5.554
Authors: Juan Morote; Imma Comas; Roser Ferrer; Lucas Regis; Anna Celma; Anna Santamaría; Jacques Planas; Enrique Trilla Journal: Eur Urol Open Sci Date: 2020-06-22