Pituitary tumor needs surgery when it grows to 3 cm. 1. Pituitary tumor is a kind of common tumor in the brain, most of them are benign, and the early symptoms are often not particularly obvious, and because of this, it is easy to be neglected, resulting in the aggravation of the condition. 2. Pituitary tumor in the brain grows gradually in the late stage, pressing the optic nerve and affecting the hormone secretion, which may have certain influence on the patient’s vision and fertility, and even jeopardize the patient’s life safety, and it is mainly treated by surgical resection. 3. It should be noted that the size of pituitary tumor should not be used as the sole basis to determine the treatment plan, but also need to be considered according to the nature of the tumor and its impact on nerves and hormone level, such as pituitary prolactin adenoma, which can be treated conservatively with medication to control the symptoms, and if the tumor continues to grow, then it should be operated in time. When patients are diagnosed with pituitary tumor, they should choose reasonable treatment plan for treatment under the guidance of doctors.