MKI67 and gastrointestinal stromal tumor: As for the therapeutic implication of evaluating Ki67 index, Zhao et al. found Ki67 index >8% may be a negative factor to imatinib adjuvant therapy.[29] In a previous study, we found KIT mutation in high-risk and malignant GIST to indicate poor prognosis, but patients with KIT mutation benefit from the targeted therapy of imatinib.[8] It is here speculated that Ki67 expression and KIT mutation are both important independent prognostic markers of GIST.