Exploring melanoma shifts: a two-decade analysis in New Zealand.

AIMS: New Zealand melanoma incidence rates are amongst the highest in the world. The study aims to provide information on the incidence of cutaneous melanoma in New Zealand from 2000 to 2022.

METHODS

De-identified data were extracted from the New Zealand Cancer Registry using the ICD-10 code for malignant melanoma (C34) and melanoma in situ (MIS) (D03) from 2000 to 2022. Statistical analysis was performed to calculate melanoma incidence rates.

RESULTS

Invasive melanoma (IM) incidence rates demonstrated an increasing trend from 2000 to 2008 (+1.10 per 100,000 person-years per year), followed by an inflection point at 2008 and then a decreasing trend from 2008 to 2022 (-0.28 per 100,000 person-years per year), which was not statistically different from zero/no change. MIS incidence increased from 30.3 to 72.1 per 100,000 person-years between 2000 and 2022.

CONCLUSIONS

The incidence of IM in New Zealand has plateaued in the last decade and was associated with an increase in MIS incidence over the same period. While this trend is encouraging, further research is required to investigate whether there is an actual decline in IM incidence.