KRAS and neoplasm: In addition, in all tumor types we analyzed clinical and molecular associations separately for PIK3CA mutations in exon 9 (helical domain) and exon 20 (kinase domain), and found that PIK3CA mutations in exon 9 compared to others (wt PIK3CA, PIK3CA exon 20 mutations) had a trend toward an association with simultaneous KRAS mutations (17/46 [37%] vs. 36/162 [22%]; p=0.05), had a trend toward association with BRAF mutations (6/42 [14%] vs. 9/137 [7%]; p=0.12), and was significantly associated with MAPK mutations (23/33 [70%] vs. 48/99 [48%]; p=0.04).