BRAF and thyroid cancer, nonmedullary, 2: The incidence of BRAF and RAS mutations in PTC correlates well with the individual histological subtypes: the classical subtype of PTC, as well as other PTC subtypes with a papillary growth pattern, and the infiltrative follicular variant of PTC are classified as BRAF-like malignancy, whereas FTC and the invasive encapsulated variant of PTC both belong to the RAS-like category (1, 9, 31).