Results of Blueprint Phase 2

The recent publication “PD-L1 Immunohistochemistry Comparability Studying Real-Life Clinical Samples: Results of Blueprint Phase 2 Project” reports on the exercise of comparing the staining and scoring of the well-known commercial PD-L1 clones.

The recent publication “PD-L1 Immunohistochemistry Comparability Studying Real-Life Clinical Samples: Results of Blueprint Phase 2 Project” reports on the exercise of comparing the staining and scoring of the well-known commercial PD-L1 clones. This study is noteworthy in several ways. It utilized NSCLC specimens from a global spectrum of medical institutions, involved expert thoracic pathologists from 14 countries, and the scoring was performed on glass slides as well as digitally. This real-world assessment is a follow-up to the Blueprint 1 Initiative. HistoGeneX was selected as a central site to conduct the IHC staining using the different clones and then subsequently scanned whole slide images. Then using the HistoGeneX PathoTrainer™ system, a HistoGeneX expert pathologist conducted training for the participant pathologists. 

There are several compelling conclusions as described in the publication.

  1. There was a high concordance between pathologists for tumor cell PD-L1 expression.
  2. However, the concordance for immune cell PD-L1 expression was unsatisfactory.
  3. Scoring for tumor cell PD-L1 expression on digital slides or glass slides was equivalent.

For more information on Blueprint 2, our experience with PD-L1 staining and scoring systems, or our PathoTrainer digital training platform, please This email address is being protected from spambots. You need JavaScript enabled to view it..