Aims <p>Localisation of non-palpable isolated or oligometastatic disease can be an intraoperative challenge. This quality improvement study aims to demonstrate the novel use of intraoperative ultrasound (IOUS) in localising oligometastatic disease. We evaluated its clinical effectiveness in comparison with the gold-standard wire-guided localisation technique in localising oligometastatic disease.</p> Methods <p>We assembled a database of patients at a specialist tertiary referral centre in the United Kingdom who had IOUS-guided or wire-guided tumour localisation and conducted informal interviews with two Plastic Surgery Consultants, a Consultant Radiologist and a Radiographer. We retrospectively analysed the effectiveness of IOUS guidance in localising cancer metastasis, focusing on physician-reported patient safety, clinical outcomes, costs and implementation and compared this to the wire-guided technique.</p> Results <p>Over the last 8 years, 19 patients had IOUS-guided tumour localisation, and 8 patients had wire-guided localisation since its on-site implementation 3 years ago. A retrospective cohort analysis was performed comparing 8 patients who underwent wire-guided tumour localisation between 2022 and 2024 with 8 patients who received IOUS-guided tumour localisation over the same period. Although IOUS extended the duration of surgery, it was less invasive, associated with lower complication rates (12.5% vs. 25.0%) and offered real-time reassurance. IOUS use was £12.65 (18%) cheaper and easier to implement compared with wire-guided localisation. Since 2017, IOUS-guided localisation has been associated with a low positive margin rate of 5.26% and a re-excision rate of 11.1%.</p> Conclusion <p>The advantages of using IOUS for patient safety, cost-effectiveness and overall outcomes highlight its role in clinical practice and the need for a standardised protocol for its implementation. Conducting a large-scale multi-centre study is necessary to improve the generalisability of findings.</p>