Expanding outpatient surgery to the increasing number of procedures and patient populations warrants continuous evaluation of postoperative outcomes to ensure the best care and safety. We describe adverse postoperative outcomes and transfer rates related to anesthesia in a large sample of patients who underwent same-day cancer surgery at a freestanding ambulatory surgery center. Between January 2017 and June 2021, 3361 cancer surgeries, including breast and plastic, head and neck, gynecology, and urology, were performed. The surgeries were indicated for diagnosis, staging, and/or treatment. We report the incidence of transfers and adverse postoperative outcomes related to anesthesia. Breast and plastic surgeries were the most common (1771, 53%), followed by urology (1052, 31%), gynecology (410, 12%), and head and neck surgeries (128, 4%). Based on patients'first procedure, comorbidity levels were highest for urology (75% American Society of Anesthesiologists physical status score 3, 1.7% score 4) and lowest for breast surgeries (31% score 3, 0.2% score 4). Most gynecology surgeries used general anesthesia (97.6%), whereas breast surgeries used the least (38%). A total of sevenpatients (0.2%; 95% CI: 0.08%-0.4%) were immediately transferred to an outside hospital; fourdue to anesthesia-related reasons. Only 7 (0.2%) patients needed additional postoperative care related to anesthesia-related adverse events, specifically cardiac events (4), difficult intubations (2), desaturation (1), and agitation, nausea, and headache (1). The incidence of anesthesia-related adverse postoperative outcomes is low in cancer patients undergoing outpatient surgeries at our freestanding ambulatory surgery center. This suggests that carefully selected cancer patients, including patients with metastatic cancer, can undergo anesthesia for same-day surgery, making cancer care accessible locally and reducing stress associated with travel for treatment. More research investigating complication rates related to surgery and to cancer disease trajectory are needed to establish a complete evaluation of safety for outpatient cancer surgery.