PIK3CA and neoplasm: The loss of TSC2 disrupts this pathway, potentially leading to unregulated mTOR activation and subsequent tumor progression.12,13 Additionally, our results indicate that PIK3CA gene amplification is significantly associated with recurrence, a finding consistent with those of previous studies.22,23PIK3CA gene amplification was detected only in tumors that concomitantly harbored PIK3CA mutations (data not shown), suggesting a synergistic effect leading to enhanced PIK3CA activation.