Pre-specified exploratory correlative assessments
tumor, Tumor
PATHOLOGY, TUMOR, INFILTRATION, TUMOR
All patients were required to undergo a baseline tumor biopsy within 28 days prior to starting trial treatment, and then underwent a second tumor biopsy of the same site after the IFN-γ induction phase but before receiving nivolumab. Tumor specimens were to be evaluated by immunohistochemistry for PD-L1 expression and immune cell infiltration as pre-planned exploratory analysis. Biopsy samples underwent routine pathology review to determine cellularity and tumor presence via hematoxylin and eosin stain. PD-L1 expression was determined via immunohistochemistry (IHC) utilizing VENTANA PD-L1 (SP263) and calculated using the tumor proportion score (TPS)