Comparative study of programmed cell death ligand-1 immunohistochemistry assays using 22C3 and 28-8 antibodies for non-small cell lung cancer: Analysis of 420 surgical specimens from Japanese patients. (November 2018)

• Record Type: Journal Article
• Authors: Saito, Tomohito; Tsuta, Koji; Ishida, Mitsuaki; Ryota, Hironori; Takeyasu, Yuki; Fukumoto, Kento J.; Matsui, Hiroshi; Taniguchi, Yohei; Yanagimoto, Hiroaki; Kurata, Takayasu; Murakawa, Tomohiro
• Is Part Of: Lung cancer. Volume 125(2018)
• Page Start: 230
• Page End: 237
• Publication Date: 2018-11
• Subjects: CLIA clinical laboratory improvement amendments -- IHC immunohistochemistry -- NPA negative percent agreement -- NSCLC non-small cell lung cancer -- OPA overall percent agreement -- PD-1 programmed cell death-1 -- PD-L1 programmed cell death ligand-1 -- PPA positive percent agreement -- SCLC small cell lung cancer; Programmed cell death ligand-1 -- Programmed cell death-1 -- Immunohistochemistry -- 22C3 -- 28-8 -- Overall percent agreement -- Positive percent agreement -- Negative percent agreement; Lungs -- Cancer -- Periodicals; Lung Neoplasms -- Abstracts; Lung Neoplasms -- Periodicals; Poumons -- Cancer -- Périodiques; Lungs -- Cancer; Periodicals; Electronic journals; Electronic journals; 616.99424
• DOI: 10.1016/j.lungcan.2018.10.005
• Languages: English
• ISSNs: 0169-5002

Abstract

Highlights: General agreement in tumoral PD-L1 detection between 22C3 and 28-8 was satisfactory. Dako 22C3 revealed a significantly higher tumoral PD-L1 expression compared to 28-8. Positive results of 22C3 (reference) and those of 28-8 (comparator) showed discordance. The results of 28-8 could be translated to those of 22C3 but not vice versa. Abstract: Objectives: Multiple programmed cell death ligand-1 (PD-L1) immunohistochemistry assays are currently used as companion or complementary diagnostic tools for anti-programmed cell death-1 immunotherapies. We aimed to characterize two PD-L1 immunohistochemistry assays (Dako 22C3 and 28-8) for non-small cell lung cancer (NSCLC) in clinical laboratories. Materials and methods: Surgical specimens from 420 patients with pathological stages IA to IIIA NSCLC were investigated. The archived samples were freshly cut into 5-μm-thick sections stained with antibodies 22C3 and 28-8, and tumoral PD-L1 expression was evaluated in two clinical laboratories, respectively. Overall, positive, and negative percent agreement (OPA, PPA, and NPA, respectively) at specified PD-L1 cutoffs were calculated to assess the concordance between 22C3 and 28-8 assays. Results: Tumoral PD-L1 expression of ≥ 1% was detected by either 22C3 or 28-8 assays in 176 cases (41.9%), whereas 22C3 revealed a significantly higher tumoral PD-L1 expression compared to 28-8 (median 30% vs. 10%, p < 0.0001). OPA was 89.0, 90.2, and 91.9% at 1, 25, and 50% cutoff levels. When 22C3 was compared to a standard assay 28-8, the PPA was 85.5, 98.3, and 94.9%, whereas NPA was 91.0, 89.0, and 91.6% at 1, 25, and 50%. On the other hand, when 28-8 was compared to 22C3, PPA was 84.4% at 1%, but it decreased to 58.3 and 53.6% at 25 and 50%; whereas NPA remained high (91.7, 99.7, and 99.4% at 1, 25 and 50%, respectively). Conclusion: Our analysis revealed that, despite the high OPA, there was discordance in the PPA between 22C3 as a standard assay and 28-8 as a comparator assay at 25% and 50% PD-L1 cutoff levels, indicating that the results of 28-8 could be translated to those of 22C3 but not vice versa.