DP23 Malignant melanoma: a 1-year retrospective analysis of clinical and histopathological data

Abstract Malignant melanoma (MM) rates in the UK are rising. Epidemiological and clinical data are necessary to better characterize the at-risk population, support early detection and improve outcomes. This study aims to investigate the demographic, clinical and histopathological profile of cases of MM at a UK histopathology centre, and to evaluate the clinical outcomes and compliance with National Institute for Health and Care Excellence (NICE) guidelines. All cases of MM and melanoma in situ received by the local histopathology centre between June 2018 and June 2019 were retrieved using WinPath software. Clinical data over the 5-year follow-up period (until 2024) were extracted retrospectively from National Health Service (NHS) patient records. This information was subsequently recorded and analysed in Microsoft Excel. Local NHS governance and ethical approvals were received to conduct this study. This study included 229 patients (130 men, 99 women), with an average age of 67 years, the largest subgroup being men aged 60–69 years (17%). Among these 229 patients, 206 cases of MM and 32 cases of melanoma in situ were diagnosed. The majority of cases of MM (52.4%) were pathological stage 1a (pT1a), with ‘superficial spreading’ being the most commonly reported type (25.2%). The torso was the predominant site for MM, representing 44.2% of cases, with the back being the most common location in men (33.6%) and the lower leg in women (18.4%). Fitzpatrick skin type was documented for 70% of patients, the most common being type II (51.2%). At the time of diagnosis, most patients had a performance status of 0 (65%), and only nine patients (3.9%) were immunocompromised. Of those eligible for sentinel lymph node biopsy (SLNB), 57% did not undergo the procedure. In many cases (46.9%), SLNB was contraindicated due to patient factors, while 36.7% declined the procedure. Regarding compliance with NICE melanoma clinical guideline recommendations, 77% of patients received an information leaflet, 85% were provided with clinical nurse specialist details, and 91% had vitamin D levels measured. Among those patients who were eligible for SLNB but did not undergo the procedure, only 18% underwent a surveillance ultrasound scan of the draining lymph nodes. The proportions of patients with MM developing local recurrence, lymph node involvement and distant metastases were 1.3%, 7.6% and 7.6%, respectively. Additionally, 15 patients died directly due to melanoma. In this study, melanoma predominantly occurred in a light-skinned older male population. While most cases were diagnosed early and managed appropriately, opportunities for improving management have been identified.