PIK3CA and neoplasm: In the context of the BEECH trial, dynamic changes in circulating tumor DNA were used as a surrogate to predict long-term outcome: median progression-free survival was 11.1 months in patients with suppressed ctDNA at four weeks and 6.4 months in patients with high ctDNA; there was no difference in the level of ctDNA suppression between patients randomized to Capivasertib or placebo overall or in the PIK3CA mutant subpopulation [320].