PD-L1 Testing in Gastric Cancer by the Combined Positive Score of the 22C3 PharmDx and SP263 Assay with Clinically Relevant Cut-offs
| Autor: | Yujun Park, Jiwon Koh, Hee Young Na, Hyung Ho Kim, Hye Seung Lee, Yoonjin Kwak, Do Joong Park, Keun Wook Lee, Sang Hoon Ahn |
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| Rok vydání: | 2020 |
| Předmět: |
0301 basic medicine
Cancer Research medicine.medical_specialty Clinical Decision-Making Gastroenterology B7-H1 Antigen Programmed cell death ligand 1 SP263 assay 03 medical and health sciences 0302 clinical medicine Predictive Value of Tests Stomach Neoplasms Internal medicine PD-L1 Biomarkers Tumor medicine Humans Tissue microarray biology business.industry Patient Selection Cancer Advanced gastric cancer medicine.disease Immunohistochemistry Gastric neoplasms 030104 developmental biology Oncology 030220 oncology & carcinogenesis biology.protein Original Article Reagent Kits Diagnostic business 22C3 pharmDx Programmed death |
| Zdroj: | Cancer Research and Treatment : Official Journal of Korean Cancer Association |
| ISSN: | 2005-9256 1598-2998 |
| Popis: | Purpose We provide a comparison between 22C3 pharmDx and SP263 assay, for evaluating programmed death ligand 1 (PD-L1) expression in advanced gastric cancer (GC) patients.Materials and Methods The PD-L1 immunohistochemistry by 22C3 pharmDx and SP263 assays was performed in the center of the tumor (CT) and invasive margin (IM) in 379 GC tissues using tissue microarrays and interpreted as combined positive score (CPS) and tumor proportion score (TPS). Of the total samples, 55 samples were independently reviewed by five pathologists.Results The two assays showed a high correlation in both the CPS and TPS. At a CPS ≥ 1 cut-off, 219 (57.8%) and 231 (60.9%) GCs were positive for PD-L1 with the 22C3 and SP263 assays, and at ≥ 10 cut-off, 37 (9.8%) and 36 (9.5%) GCs were positive, respectively. The overall percent agreement (OPA) was greater than 90% with CPS ≥ 1 and ≥ 10 cut-offs, and TPS ≥ 1% and ≥ 10% cut-offs. There was higher OPA between the two assays with a CPS cut-off ≥ 10 (99.2%) than ≥ 1 (94.7%). The percent agreement between the CT and IM was higher with a CPS cut-off ≥ 10 (92.9%) than ≥ 1 (77.6%). Patient with positive expression at CPS ≥ 5 cut-off had a significantly better outcomes in both assays. Interobserver variability among five pathologists was higher than the assay variability.Conclusion Two assays for PD-L1 expression in GC showed high agreement. These results provide guidance for selecting eligible patients with GC for pembrolizumab treatment. |
| Databáze: | OpenAIRE |
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