PIK3CA and gastric cancer: In the last year, several reports in other tumor types have analyzed whether ARID1A alterations are restricted to selected genetic pathways in specific tumor types: in gastric cancer, ARID1A mutations are also associated with TP53 wild type tumors [46] and in ovarian clear-cell carcinoma ARID1A alterations are reported to be an early event associated with PIK3CA mutations [47], [48].