Acta Dermato-Venereologica 97-6 97-6CompleteContent | Página 13

CLINICAL REPORT Multiple Primary Melanomas: A Common Occurrence in Western Sweden Magdalena CLAESON 1 , Paul HOLMSTRÖM 2 , Stefan HALLBERG 2 , Martin GILLSTEDT 1 , Helena GONZALEZ 1 , Ann-Marie WENNBERG 1 and John PAOLI 1 1 Department of Dermatology and Venereology, Sahlgrenska Academy, and 2 Centre for Health Care Improvement, Chalmers University of Technology, Gothenburg, Sweden Patients diagnosed with a single primary cutaneous melanoma are at increased risk of developing multiple primary melanomas. The aim of this study is to des- cribe the epidemiology of multiple primary melanomas (invasive and in situ) in Western Sweden. Data from the Swedish Melanoma Registry from 1990 to 2013 revealed that 898 patients (7.4%) developed 2,037 multiple primary lesions and 11,254 patients develo- ped single lesions. The proportion of subsequent le- sions that were melanoma in situ was 47%, compared with 26% of first melanomas (p  < 0.0001).The median and mean time to diagnosis of a subsequent melano- ma was 38 and 58 months (95% confidence interval (CI), 53–62 months). In total, 49% of subsequent me- lanomas were detected within 3 years. Patients and physicians should be aware of the high proportion of multiple primary melanomas in Western Sweden, es- pecially during the first years of follow-up. Key words: cutaneous malignant melanoma; multiple primary melanomas; second primary melanoma; synchronous melano- mas; subsequent melanomas; time to diagnosis. Accepted Dec 12, 2016; Epub ahead of print Dec 13, 2016 Acta Derm Venereol 2017; 97: 715–719. Corr: Magdalena Claeson, Department of Dermatology and Venereology, Sahlgrenska Academy, SE-413 45 Gothenburg, Sweden. E-mail: magda- [email protected] 715 I ncidence rates of cutaneous malignant melanoma (melanoma) are increasing worldwide in the fair- skinned population (1). Early detection and increased survival have resulted in a high proportion of melanoma survivors. It is well known that patients diagnosed with a single primary melanoma are at elevated risk of develo- ping multiple primary melanomas during their lifetime. Multiple lesions can be detected synchronously at a single visit or during follow-up (i.e. subsequent mela- nomas). Important risk factors for developing multiple primary tumours are: age, fair skin type, family history of melanoma and presence of many or large naevi (2, 3). Research has shown that the percentage of patients who develop multiple primaries ranges from 0.2% to 8.6% (4, 5). Subsequent melanomas in patients who attend follow-up have been noted to present with a thinner Breslow thickness than those who do not attend follow-up (6, 7). Previous studies have also calculated the latency of development of subsequent melanomas; they are most common within the first years after initial diagnosis (2, 4, 5, 8, 9). Sweden is among the countries with the highest inci- dence of melanoma in the world. The incidence increases annually, by 5.5% for men and 5.2% for women and is currently 19.5 for men and 20.9 for women/100,000 po- pulation (World Standard Population year 2000) (10, 11). The increasing incidence makes melanoma a major health issue, being the 6 th leading cancer in the country for men and the 5 th leading cancer for women. Despite increasing incidence, the national mortality rate has remained low, at 2.8 deaths/100,000 population (World Standard Popula- tion year 2000) (10). Thus, Sweden has a high proportion of patients diagnosed with a single primary melanoma at risk of developing multiple primary melanomas. There are a few previous studies investigating dif