MKI67 and neoplasm: Patients who had not received surgery or radiotherapy before (P < 0.001), with non-invasive tumor (P < 0.001) or predicted as non-invasive by Knosp grading (P = 0.008), with microadenoma predicted on MRI (P = 0.011), with Ki-67 ≤ 2 (P = 0.074) were more likely to achieve immediate remission.