PIK3CA and thyroid cancer: Upon analyzing the pathways, 13 of the 15 patients were found to be affected by the known thyroid cancer oncogenic pathways, and 10 of these patients had somatic mutations, copy number gain or copy number amplification of the RAS (H/K/NRAS) gene, which are upstream of the MAPK and PIK3CA/AKT pathways (Fig. 3B).