Ki-67 is an important biomarker in breast cancer diagnosis, which gives prognostic information about the specific cancer. The resulting proliferation index of the tumor can support treatment selection and thus, correct assessment of Ki-67 levels is very important. To support the quality of the Ki-67 IHC staining in the respective labs, participation in external quality assessment (EQA) programs, like the ones offered by the UK National External Quality Assessment Scheme for Immunocytochemistry and In-Situ Hybridisation (UK NEQAS ICC & ISH) is recommended and has shown to improve laboratory performance.

In this study, UKNEQAS shows the application of new cell line based control materials to robustly identify false positive and suboptimal Ki-67 IHC staining using digital image analysis based on Visiopharm.

Fitim Berisha¹, Dawn Wilkinson¹, Lila Zabaglo¹, Suzanne Parry¹, Andrew Dodson^1,2

1. UK NEQAS ICC & ISH, 5 Coldbath Square, London EC1R 5HL UK
2. Corresponding author: adodson@ukneqasiccish.org