In the preoperative waiting area, the patients are randomly assigned and divided into two groups according to the allocation sequence table (corresponding to 1:1 randomization) generated by the computer. The propofol group was both induced and maintained at an effect-site concentration (Ce) of 2.0-4.0 mcg/mL by a target-controlled infusion (TCI) system. The sevoflurane group was maintained via sevoflurane vaporizer between 1% and 3% (target minimum alveolar concentration of 0.7-1.3). The following patient data were recorded, the type of anesthesia, sex, age at the time of surgery, preoperative Karnofsky performance status (KPS) score and functional capacity, the postoperative complications within 30 days (according Clavien-Dindo classification), American Society of Anesthesiologists(ASA) physical status scores, tumor size, intraoperative blood loss/transfusion, duration of surgery, duration of anesthesia, total opioid (remifentanil/fentanyl/ propofol) use, postoperative radiation therapy, postoperative chemotherapy, postoperative concurrent chemoradiotherapy, the presence of disease progression, and 6-month, 1-year, and 3-year overall survival and Karnofsky performance status score were recorded.

During the operation, the dose of anesthetic drugs (propofol/ fentanyl /remifentanil and sevoflurane/ cisatracurium/ rocuronium) are adjusted to maintain the mean arterial pressure and heartbeat fluctuations within 20% of the baseline value and Entropy (or BIS) value at 40-60in both groups. The following patient data were recorded, the type of anesthesia, sex, age at the time of surgery, preoperative Karnofsky performance status (KPS) score and functional capacity, the postoperative complications within 30 days (according Clavien-Dindo classification), ASA physical status scores, tumor size, intraoperative blood loss/transfusion, duration of surgery, duration of anesthesia, total opioid (remifentanil/ fentanyl/ propofol) use, postoperative radiation therapy, postoperative chemotherapy, postoperative concurrent chemoradiotherapy, the presence of disease progression, and 6-month, 1-year, and 3-year overall survival and Karnofsky performance status score were recorded.

Inclusion Criteria:

1. Twenty to eighty-year-old.
2. ASA class I-III.
3. Patients undergoing elective craniotomy for primary brain tumors under general anesthesia.

Exclusion Criteria:

1. Severe mental disorder
2. Poor liver function
3. Pregnant or lactating women
4. Morbidly obese
5. Allergy to any of the drugs used in this study
6. Recurrent tumor or repeat surgery
7. Biopsy cases
8. Incomplete outcome-data
9. Palliative treatment after surgery
10. simultaneous treatment of other malignancies
11. Emergency surgery
12. Presence of other malignant tumors
13. Combined propofol and inhalation anesthesia or other anesthetics, such as ketamine or dexmedetomidine
14. Diagnosed as benign brain tumor
15. cerebellum tumor and pituitary gland tumor.