C. Rowe, M. Law, J. Palmer, S. MacGregor,N. Hayward, K. Khosrotehrani1,
Multiple primary melanomas occur fre-quently, particularly in high risk populations such as Aus-tralia. Currently, little is known as to how this impactssurvival for patients. We aimed to establish whether mela-noma survival is worse for patients with multiple melanomascompared to those with a single invasive primary melanoma.
A cohort study was conducted, with patientssourced from an Australian population. Follow-up informa-tion was collected retrospectively from registry data. Sur-vival analysis was performed using four different models,each selecting a different index melanoma lesion, withadjustment for established clinicopathological factors.
1068 stage I and II melanoma patients were fol-lowed up for a median of 24.4 years. Multiple primary mel-anomas occurred in 17.8% of the cohort (190 patients).Older age and male gender were found to be risk factorsfor developing multiple melanomas. Other clinicopatholog-ical parameters were similar between the multiple and thesingle primary melanoma groups. After adjustment forage, sex and Breslow thickness, multiple primary mela-noma was a hazard for death from melanoma, across allfour models, reaching signiﬁ cance in the model consider-ing the last invasive lesion as the index melanoma(HR = 2.76, p = 0.017).
Patients with multiple invasive primary mel-anomas seem more at risk of death from melanoma, inde-pendent of known prognostic factors. These results havepotential implications on clinical practice, suggesting thatit may be bene ﬁcial for increased follow up regimens forthese high risk individuals.