PIK3CA and colorectal carcinoma: A total of 1603 patients in three studies 7, 12, 13 were pooled for analysis of the association between high F. nucleatum levels and PIK3CA mutation through the fixed-effects model, and there was no correlation between and PIK3CA mutation in CRC (OR = 1.21, 95% CI: 0.74-1.97, P = 0.45) (supplemental Figure 2E).