Journal article

SP142 PD-L1 Scoring Shows High Interobserver and Intraobserver Agreement in Triple-negative Breast Carcinoma But Overall Low Percentage Agreement With Other PD-L1 Clones SP263 and 22C3

Jia-Min B Pang, Belinda Castles, David J Byrne, Peter Button, Shona Hendry, Sunil R Lakhani, Vanathi Sivasubramaniam, Wendy A Cooper, Jane Armes, Ewan KA Millar, Wendy Raymond, Samuel Roberts-Thomson, Beena Kumar, Marian Burr, Christina Selinger, Kate Harvey, Charles Chan, Jane Beith, David Clouston, Sandra A O'Toole Show all



SP142 programmed cell death ligand 1 (PD-L1) status predicts response to atezolizumab in triple-negative breast carcinoma (TNBC). Prevalence of VENTANA PD-L1 (SP142) Assay positivity, concordance with the VENTANA PD-L1 (SP263) Assay and Dako PD-L1 IHC 22C3 pharmDx assay, and association with clinicopathologic features were assessed in 447 TNBCs. SP142 PD-L1 intraobserver and interobserver agreement was investigated in a subset of 60 TNBCs, with scores enriched around the 1% cutoff. The effect of a 1-hour training video on pretraining and posttraining scores was ascertained. At a 1% cutoff, 34.2% of tumors were SP142 PD-L1 positive. SP142 PD-L1 positivity was significantly associated with tum..

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Funding Acknowledgements

The authors thank Heather Thorne, Eveline Niedermayr, Sharon Guo, all the kConFab research nurses and staff, the heads and staff of the Family Cancer Clinics, and the Clinical Follow Up Study (which has received funding from the NHMRC, the National Breast Cancer Foundation, Cancer Australia, and the National Institute of Health [US]) for their contributions to this resource, and the many families who contribute to kConFab.