P006 An evaluation of digital mole mapping for patients at high risk of melanoma

Abstract Detection of melanoma at an early stage is associated with increased survival and therefore is the priority for secondary dermatology care services. Digital mole mapping (DMM) is a noninvasive way of noting early changes in pigmented lesions and utilizes software to facilitate serial monitoring of pigmented skin lesions. However, evidence of the utility of this technology in National Health Service services is minimal. Therefore, we set out to examine our service. We evaluated our DMM clinic for patients at high risk of developing melanoma (June 2019 to June 2024). Referral criteria include three of: history of melanoma, ≥ 100 common naevi, at least five atypical naevi, at least two larger acquired naevi (> 8 mm), at least one first-degree relative with melanoma, and known genetic predisposition (BAP1, CDK4, CDKN2A, POT1 genes). We used FotoFinder automated total body mapping (ATBM) (FotoFinder Systems, Inc., Columbia, MD, USA) and dermoscopic serial imaging. Over 5 years, we reviewed 218 patients (46.5% men, 53.5% women; mean age 54.2 years) in 976 consultations (163 appointments per year, SD 59.4; mean 4.2 attendances per patient). New referrals made up 36.3 cases per year (SD 12.6). The DNA rate was 6.2%. In total, 73 (33.5%) patients were referred with previous single melanomas (mean age of onset 48.2 years) and 54 (24.8%) patients with multiple melanomas, with one patient having had six melanomas. Overall, 10.6% of patients with data had red hair; 15.1% of all patients had Fitzpatrick skin type I, 64.7% type II and 4.6% type III (none had types IV–VI). Ten cases (average age 54.4 years) were immunosuppressed, with a range of aetiologies from lymphoma (n = 3) to azathioprine for inflammatory bowel disease (n = 2). In total, 47.2% of cases had > 100 naevi for monitoring and 71.1% had more than five dysplastic naevi. One-sixth (16.4%) of all consultations resulted in a planned excision, of which 80% were melanoma, dysplastic naevi or other skin malignancy (164 lesions: melanoma 15.2%, severely dysplastic naevus 4.8%, dysplastic naevus 54.8%); 21.9% of excisions were planned at the first DMM clinic consultation. Of the melanomas, 50% were in men and 50% were truncal. All melanomas (100%) were classed as thin (mean Breslow 0.4 mm). No local, nodal or metastatic recurrences were identified. In conclusion, we describe the use of ATBM and dermoscopic serial imaging in a high-risk cohort. We estimate that in the timespan reported we have monitored around 12 000 lesions, and of these we have only needed to excise 1.4%, with a high hit rate of 80% warranting excision. Because 84% of melanomas were detected at follow-up, and by Breslow thickness they were uniformly thin, this supports the effectiveness of the follow-up approach here. This evaluation of individuals with numerous melanocytic naevi supports this approach as an effective use of resources.