P199 National trends in melanoma incidence rates by stage at diagnosis: England 2013–2023

Abstract

Stage at diagnosis is a key determinant of survival in melanoma, and trends in melanoma rates by stage distribution can aid public health strategies. We identified national trends in melanoma incidence by stage in England, 2013–23. Joinpoint regression analysis of crude incidence rates and average annual percentage change (APC) in incidence was conducted using data from National Disease Registration Service (NDRS) national statistics. Cases were categorized by stage at diagnosis, and incidence rates were reported per 100 000 person-years as either crude or age- and gender-standardized rates with 95% confidence intervals (CIs) using the 2013 European standardized population. Between 2013 and 2023, 164 228 cases of melanoma were registered, with the majority diagnosed as stage I (59.5%, n = 97 711), followed by stage II (18.4%, n = 30 178), stage III (6.7%, n = 11 067) and stage IV (2.6%, n = 4222). Stage was unknown for 21 050 cases (12.8%). Overall, during this period the melanoma incidence rate increased by 2.5% annually (95% CI 0.57–4.58; P = 0.01). Pre-COVID-19 (2020) pandemic trends were +2.13% APC (95% CI 1.41–2.91; P < 0.001), with a fall in 2020, but there were not enough data for post-COVID-19 trend analysis. Stage I (APC +1.31%, 95% CI −1.03 to 3.76; P = 0.25) and stage II tumours (APC +2.25%, 95% CI 0.12–4.55; P = 0.04) increased less than stage III (APC +6.05%, 95% CI 3.08–9.57; P < 0.001) and stage IV tumours (APC +4.41%, 95% CI 2.24–6.92; P < 0.001). For tumours of unknown stage, the APC was +5.74% (95% CI −2.87 to 17.7, P = 0.16). Melanoma incidence rates continue to rise in England, with greater increase seen in stage III and IV and unknown-stage tumours than stage I and II. This is likely multifactorial, with contributing factors including increased use of sentinel lymph node biopsy resulting in upstaging of earlier stage tumours, and possible stabilization of overdiagnosis due to diagnostic drift. Pandemic trends likely need more years of data to be fully understood.