CD68 and neoplasm: Semi-quantitative evaluation of CD68 and CD163 expression at the tumor front revealed that 16 (42%), 13 (34%) and 9 (24%) CRCs had low, moderate and high infiltration of CD68-positive cells, respectively, and 33 (87%), 3 (8%) and 2 (5%) CRCs had low, moderate and high infiltration of CD-163-positive cells, respectively (S2 Table).