Using a large (N= 25 493) population-based cohort from Queensland, Australia, we compared melanoma survival among cases with a single invasive melanoma only against those who also had a diagnosis of a single in situ melanoma. After adjustment for sex, age, body site, clinicopathological subtype, thickness and ulceration, it was found that there was no difference (P = 0.99) in 10-year melanoma-specific mortality following a diagnosis of an invasive lesion, whether or not an in situ melanoma was also present. We conclude that in situ melanomas do not alter the prognosis of an invasive melanoma.
Keywords: in situ; invasive; melanoma; survival.
© 2016 The Australasian College of Dermatologists.