purpose: the aim of the present study was to detect the expression of p-glycoprotein (p-gp) and multi-drug resistance associated protein 1 (mrp1) in retinoblastoma tumors, and analyze the relationship between its expression, the clinico-pathological features and recurrence. methods: p-gp and mrp1 expression in formalin-fixed paraffin-embedded retinoblastoma bearing ocular tissue sections from 2...