Session 8: pathology and clinicopathological correlations 077 THE RELIABILITY OF IMMUNOHISTOCHEMICAL ANALYSIS OF TUMOR MICROENVIRONMENT IN FOLLICULAR LYMPHOMA; A VALIDATION STUDY FROM THE LUNENBURG LYMPHOMA BIOMARKER CONSORTIUM (LLBC)

Introduction: Cell populations of the tumor microenvironment have been implicated for prognostic relevance in follicular lymphoma (FL) The results of immunohistochemistry (IHC) based studies are contradictory, possibly due to differences in treatment protocols and patient selection. In addition, the reproducibility of scoring of cell densities and infiltration patterns has not been studied thus far and can be expected to be of major impact. A validation study was performed to 1) estimate the variation and reproducibility of manual scoring, 2) determine if a systematic difference between manual and computer-assisted scoring exists, 3) evaluate if computer-assisted scoring is more reliable assuming that flow cytometry (FACS) is the gold standard.