PTEN and neoplasm: None of these trials demonstrated a significant difference between the PTEN-loss/low and the PTEN-positive populations in response to the tested drug.11,13,14 We applied two scoring approaches in the current study: one used the most stringent criterion of no staining in invasive tumor cells to define PTEN loss, and the other adopted the most liberal cutoff of no staining in ⩾50% of tumor cells to define PTEN low, as in the FAIRLANE and LOTUS trials.