Touch preparation for rapid onsite evaluations of renal mass biopsies: concordance rate, pearls, and pitfalls

•Renal mass core needle biopsies revealed a subset of non-surgical conditions.•Rapid on-site evaluation using touch preps was highly concordant with final biopsy findings.•Proximal tubular cells, macrophages, and angiomyolipomas are common pitfalls.•Intracytoplasmic and background vacuoles are helpful in confirming low grade RCCs.