CD68 and colorectal carcinoma: Inagaki et al.221 used double immunofluorescence with CD68 and CD163 to evaluate the number, phenotype, and distribution of TAMs in 53 colorectal cancer (CRC) patients and reported that M2 macrophages increase with tumor progression, suggesting that M2 macrophages may play an important predictive role at the frontiers of tumor invasion, where the M2/M1 ratio is more predictive of lymphatic metastasis in CRC patients.