Besides, two trials of above three studies also reported data about PIK3CA mutation detected in circulating tumor DNA(ctDNA), and fixed effect model (P = 0.50, I2 = 0%) indicated that the combination therapy had longer PFS than fulvestrant monotherapy among patients with PIK3CA-mutated ctDNA (HR = 0.52, 95%CI: 0.39–0.69). Here, PIK3CA is linked to neoplasm.