MGMT and neoplasm: In conclusion, in this study we demonstrated the expression of D2R, MGMT and VEGF in 197 different histological subtypes of pituitary adenomas, and analyzed the relationships between D2R, MGMT and VEGF expression and the association of D2R, MGMT and VEGF expression with PA clinical features including patient sex, tumor growth pattern, tumor recurrence, tumor size, tumor tissue texture and bromocriptine application.