The COVID-19 pandemic disrupted cancer care globally, and new research highlights its measurable impact on melanoma diagnosis and prognostic features across regions with differing public health strategies.
In this population-based study, researchers analyzed invasive cutaneous melanoma cases diagnosed between 2013 and 2021 using registry data from Sweden and Victoria, Australia. These regions were selected due to their contrasting approaches to pandemic control, with Sweden adopting relatively lenient measures and Victoria implementing strict lockdowns.
The findings reveal a clear pandemic-related disruption in melanoma detection. Both regions experienced an immediate decline in melanoma incidence following the onset of COVID-19 in March 2020. This reduction was largely driven by a drop in diagnoses of thin melanomas and was most pronounced among older individuals.
However, regional differences emerged over time. In Victoria, melanoma incidence remained persistently lower throughout the pandemic period, with no recovery to pre-COVID trends. In contrast, Sweden saw a gradual return to expected incidence levels after the initial decline.
Changes in tumor characteristics were modest but notable. In Victoria, although the median Breslow thickness remained stable at 0.7 mm, the distribution shifted significantly, indicating a relative increase in thicker melanomas. Sweden did not show significant changes in tumor thickness overall, but a slight increase in ulceration rates was observed.