DS16 Incidence and management of pregnancy-associated melanoma in a district general hospital in the Southeast of England

Melanoma is the most common malignancy during pregnancy (Driscoll MS, Martires K, Bieber AK et al. Pregnancy and melanoma. J Am Acad Dermatol 2016; 75: 669–78). Pregnancy-associated melanoma (PAM) is defined as any melanoma diagnosed during pregnancy or up to 1 year postpartum. PAM appears to have poorer outcomes than other melanomas (Byrom L, Olsen C, Knight L et al. Increased mortality for pregnancy-associated melanoma: systemic review and meta-analysis. J Eur Acad Dermatol Venereol 2015; 29: 1457–66). The pathophysiology of why this could be is incompletely understood. There are currently no guidelines on the management of PAM in the UK. This is part of a project to collect data nationally to identify features of PAM, and to determine potential diagnostic challenges due to pregnancy. Patients were identified from the paper notes of the skin cancer multidisciplinary meetings from a district general hospital in the south-east of England. This covered a catchment area of approximately 800 000 patients. To identify patients who were diagnosed with PAM, we investigated the cohort of patients who were registered as female and aged between 20 and 50 years, a commonly used definition in the literature. Details on the pregnancies and melanoma were obtained from the electronic medical records. Four years of data from multidisciplinary meetings were processed, from December 2019 to November 2023. During this period, there were 85 female patients of childbearing age who were diagnosed with melanoma. Six patients had PAM, five of whom were diagnosed postpartum. The Breslow thicknesses ranged from 0.3 to 2.2 mm. The patient who was identified perinatally did not have her treatment delayed due to the pregnancy, and there was no record of the placenta being sent for histology or the baby being given a full-skin examination. Regarding the outcome for these patients, when the data were collected in December 2023, five were currently under follow-up and one had completed follow-up. PAM is a relatively rare condition, but with maternal ages rising in the developed world, the incidence could be expected to increase. National data collection is therefore required to identify trends and associations to gain consensus on its management.