Intraoperative cell salvage (ICS) is a blood conservation technique utilized in major surgery, yet its application in oncologic procedures remains debated. Concerns persist about the theoretical risk of metastasis through reinfusion of tumor cells, despite the established disadvantages of allogeneic blood transfusion (ABT), such as transfusion-related reactions and immunosuppression. In this review, we discuss the historical development of ICS, the technical processes of ICS including leukocyte depletion filtration and irradiation, and experimental and clinical data regarding its safety and efficacy. In vitro studies suggest that tumor cells undergo significant structural alterations during ICS processing, and additional filtration further reduces cell load, although complete removal is not always achieved. Observational studies of predominantly moderate quality, aggregated in multiple systematic reviews, consistently report no increased recurrence rates or reduced disease-free and overall survival in patients receiving ICS. Accordingly, national and international guidelines endorse the use of ICS during oncologic surgery. Although high-quality data—preferably from randomized controlled trials—are lacking, and certainty of available evidence from observational studies is low, ICS appears to be effective and safe. The broader adoption of its use during oncologic surgery may be warranted to minimize reliance on ABT and its associated risks.