T cell infiltration (TCI) in matched renal biopsy (bx) and nephrectomy (nx) samples in renal cell carcinoma (RCC).

472Background: T cell infiltration in tumors has been investigated as a biomarker of response to checkpoint inhibitors. A neo-adjuvant trial of checkpoint inhibition in locally-advanced RCC is ongoing at Cleveland Clinic, where T cell infiltration in pre-treatment renal mass bx will be compared to post-treatment nx specimens. However, there are no data regarding the association of T cell infiltration in matched bx and nx samples without intervening treatment. Understanding this association will enable further study of this potential biomarker in future neo-adjuvant studies. Methods: Matched bx and nx samples (without intervening systemic therapy) were identified from patients with non-metastatic RCC. Demographic and pathological data were collected from chart review. Selected tissue sections from bx and nx samples of each patient were reviewed, and marked for tumor and intra-tumoral lymphocytes by the pathologist. Immunohistochemistry (IHC) was utilized to stain these selected tissue sections for T cell m...