Catharina M Korse1, Stefan Holdenrieder2, Xiu-yi Zhi3, Xiaotong Zhang4, Ling Qiu5, Andrea Geistanger6, Marcus-Rene Lisy7, Birgit Wehnl8, Daan van den Broek9, José M Escudero10, Jens Standop11, Mu Hu12, Rafael Molina13. 1. The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam 1066CX, The Netherlands. Electronic address: t.korse@nki.nl. 2. University Hospital Bonn and Center of Integrative Oncology Cologne/Bonn, Sigmund-Freud-Strasse, Bonn 25-53127, Germany. Electronic address: stefan.holdenrieder@uni-bonn.de. 3. Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China. Electronic address: xiuyizhi@aliyun.com. 4. Peking Union Medical College Hospital (PUMCH), 1Shuaifuyuan, Dongcheng District, Beijing 100730, China. Electronic address: ajxt@public3.bta.net.cn. 5. Peking Union Medical College Hospital (PUMCH), 1Shuaifuyuan, Dongcheng District, Beijing 100730, China. Electronic address: lingqiubj@aliyun.com. 6. Roche Diagnostics GmbH, Nonnenwald 2, Penzberg 82377, Germany. Electronic address: andrea.geistanger@roche.com. 7. Roche Diagnostics GmbH, Nonnenwald 2, Penzberg 82377, Germany. Electronic address: marcus-rene.lisy@roche.com. 8. Roche Diagnostics GmbH, Nonnenwald 2, Penzberg 82377, Germany. Electronic address: birgit.wehnl@roche.com. 9. The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam 1066CX, The Netherlands. Electronic address: da.vd.broek@nki.nl. 10. Hospital Clinic, University of Barcelona, Carrer Villarroel 170, Barcelona 08036, Spain. Electronic address: JMESCUDE@clinic.ub.es. 11. University Hospital Bonn and Center of Integrative Oncology Cologne/Bonn, Sigmund-Freud-Strasse, Bonn 25-53127, Germany. Electronic address: standop@uni-bonn.de. 12. Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China. Electronic address: hunthm1999@163.com. 13. Hospital Clinic, University of Barcelona, Carrer Villarroel 170, Barcelona 08036, Spain. Electronic address: RMOLINA@clinic.ub.es.
Abstract
BACKGROUND: We performed a multicenter evaluation of the Elecsys® progastrin-releasing peptide (ProGRP) immunoassay in Europe and China. METHODS: The assay was evaluated at three European and two Chinese sites by imprecision, stability, method comparison and differentiation potential in lung cancer. RESULTS: Intermediate imprecision across five analyte concentrations ranged from 2.2% to 6.0% coefficient of variation. Good stability for plasma and serum samples was shown for various storage conditions. There was excellent correlation between the Elecsys® and ARCHITECT assays in plasma (slope 1.02, intercept -2.72pg/mL). The Elecsys® assay also showed good correlation between serum and plasma samples (slope 0.93, intercept 2.35pg/mL; correlation coefficient 0.97). ProGRP differentiated small-cell and non-small-cell lung cancer (NSCLC; area under the curve 0.90, 95% CI 0.87-0.93; 78.3% sensitivity, 95% specificity; at 84pg/mL), with no relevant effects of ethnicity, age, gender or smoking. Median ProGRP concentrations were low in benign diseases (38pg/mL), other malignancies (40pg/mL) or NSCLC (39pg/mL), except chronic kidney disease above stage 3 (>100pg/mL). CONCLUSIONS: Increased stability of the Elecsys® ProGRP assay in serum and plasma offers clear benefits over existing assays. This first evaluation of a ProGRP assay in China demonstrated comparable differentiation potential among different ethnicities.
BACKGROUND: We performed a multicenter evaluation of the Elecsys® progastrin-releasing peptide (ProGRP) immunoassay in Europe and China. METHODS: The assay was evaluated at three European and two Chinese sites by imprecision, stability, method comparison and differentiation potential in lung cancer. RESULTS: Intermediate imprecision across five analyte concentrations ranged from 2.2% to 6.0% coefficient of variation. Good stability for plasma and serum samples was shown for various storage conditions. There was excellent correlation between the Elecsys® and ARCHITECT assays in plasma (slope 1.02, intercept -2.72pg/mL). The Elecsys® assay also showed good correlation between serum and plasma samples (slope 0.93, intercept 2.35pg/mL; correlation coefficient 0.97). ProGRP differentiated small-cell and non-small-cell lung cancer (NSCLC; area under the curve 0.90, 95% CI 0.87-0.93; 78.3% sensitivity, 95% specificity; at 84pg/mL), with no relevant effects of ethnicity, age, gender or smoking. Median ProGRP concentrations were low in benign diseases (38pg/mL), other malignancies (40pg/mL) or NSCLC (39pg/mL), except chronic kidney disease above stage 3 (>100pg/mL). CONCLUSIONS: Increased stability of the Elecsys® ProGRP assay in serum and plasma offers clear benefits over existing assays. This first evaluation of a ProGRP assay in China demonstrated comparable differentiation potential among different ethnicities.