DMT156-20 Keep Calm and IHC On: Practical Tips to Navigate Confusing Immunostains in Hematopathology

Course overview

Does your heart sink when you open a tray of immunohistochemical stains while working up a lymphoproliferative process? Have you ever regretted ordering an immunohistochemical stain when the results are confusing instead of confirmatory? If the answer is yes, then this is the course for you. In this practical and case-based presentation geared toward residents, fellows, community pathologists, and anyone who needs a refresher, there will be ample time for audience questions. Topics will include the differential diagnosis of CD30-positive malignant lymphomas, BCL2-negative follicular lymphoma, and cyclin D1-positive processes that are not mantle-cell lymphoma. We will discuss immunohistochemistry requiring enumeration, including the Hans algorithm, MYC and BCL2 immunostains in diffuse large B-cell lymphoma, Ki67 in mantle-cell lymphoma, and PD-L1 in primary mediastinal large B-cell lymphoma. Common pitfalls in hematopathology immunohistochemistry and how to avoid them will be covered. After this session, attendees will be empowered to tackle potentially confusing IHC in hematopathology.