NRAS and thyroid cancer, nonmedullary, 2: For NRAS genes, discordance was present in 13 cases, 2 in cytology (1 B-VI and 1 B-IV) and 11 in histology, 1 benign and 10 malignant (9 PTC and 1 FTC); for HRAS genes, discordance occurred in 9 cases, 1 in cytology (B-VI) and 8 with malignant histology (6 FC-PTC, and 2 others in PTC).