P154 Evaluation of the National Melanoma Guidelines with a focus on computed tomography scanning of stage IIB: a West of Scotland review

Abstract In June 2022, the National Institute for Health and Care Excellence (NICE) updated their melanoma management guidelines, recommending routine contrast-enhanced computed tomography (CE-CT) for melanoma of stage IIB onwards. This shift was based on evidence that stage IIC melanoma carries a higher recurrence risk than stage IIIA, prompting more frequent imaging akin to stage III follow-up schedules. However, the practical impact of these changes – particularly the balance between earlier detection and the high rate of incidental findings – remains unclear. Our aim was to assess whether routine CE-CT scanning in stage IIB melanoma expedites the detection of recurrence or progression, to evaluate adherence to NICE’s recommended scanning intervals, and to determine the burden of incidental findings in clinical practice. Following local governance approvals, we retrospectively reviewed the records of 97 patients (age range 24–97 years) diagnosed with melanoma of at least stage IIB between 1 November 2022 and 30 June 2023 across four health boards in the West of Scotland. We recorded CE-CT compliance according to whether scanning had taken place within 6 weeks of diagnosis, and at 6-monthly intervals thereafter. We also categorized abnormalities on imaging as either suspicious (e.g. lymphadenopathy, distant metastases) or incidental (e.g. abdominal aneurysm, uterine fluid, colon wall thickening, pleural plaques). In total 78 patients proceeded to scan 1, of whom 43 (55%) were scanned within 6 weeks, 20 (26%) by 12 weeks, and 15 (19%) beyond 12 weeks of diagnosis. Sixty-eight patients underwent scan 2; 39 (57%) received it within 6 months of scan 1, while the remainder experienced delays. By scan 3, only 44 patients were imaged, 36 (82%) within 6 months of scan 2. Focusing on 11 patients with stage IIB melanoma who underwent scan 1, 8 (73%) showed suspicious findings suggestive of early metastatic or nodal involvement, whereas 5 (45%) had incidental melanomas requiring additional investigations. On scan 2, nine (82%) of these patients with stage IIB melanoma had suspicious findings, with eight (73%) also exhibiting incidental lesions. Early imaging appears to uncover metastatic disease in a significant proportion of patients with stage IIB melanoma, potentially enabling prompt therapeutic intervention. However, both partial noncompliance with recommended intervals and a high rate of incidental findings pose practical challenges, emphasizing the need for clear follow-up pathways and patient education. Further prospective studies and cost-effectiveness analyses are recommended to refine surveillance protocols, optimize resource use and improve patient outcomes.