High constant incidence rates of second cutaneous melanomas

Abstract

The incidence of most epithelial cancers rises with a power of age. However, second breast cancers have a high constant incidence independent of age. The skin is one of the few other sites allowing examination of age incidence curves of second neoplasms of the same organ. We considered the risk of second primary cutaneous malignant melanoma (CMM) in a population-based series of 3,439 first CMM registered and followed-up between 1974 and 2003 in the Swiss Cantons of Vaud and Neuchâtel (about 786,000 inhabitants). A total of 43 cases of second CMM were observed vs. 9.3 expected, corresponding to a standardized incidence ratio (SIR) of 4.6. The SIR was 8.5 under age 50, 5.7 at age 50-59 and 3.5 at age 60 or over. At 20 years, the cumulative risk of second CMM was 5%. Age-specific incidence rates of second primary CMM did not vary across age groups 30-39 through 801, ranging between 1 and 2.5 per 1,000 person-years. Thus, the risk of CMM is substantially increased in subjects diagnosed with a CMM, and the relative risk is greater at younger age and declines with advancing age. The high constant incidence curve of second CMM is compatible with the occurrence of a single mutational event in a population of susceptible individuals. ' 2005 Wiley-Liss, Inc.Key words: skin; malignant melanoma; multiple tumors; incidence; cancer registryThe incidence of most epithelial cancers, including cutaneous malignant melanoma (CMM), rises with a power of age, and for CMM is about 5-fold higher at age 75-79 as compared to age 30-34. However, the incidence of breast cancer following carcinoma in situ of the breast is constant with age, with a rate around 1.4% per person-year.1 Likewise, the incidence of second breast cancer in women treated for an invasive breast cancer, who often have only one breast at risk, is constant with age, 2,3 around 0.7% per person-year. 4 The skin is one of the few other sites that allow examination of age incidence curves of second neoplasms of the same organ after removal of a first primary. We have therefore considered the incidence of second CMM in subjects treated for a first CMM using the data sets from the Cancer Registries of the Swiss Cantons of Vaud and Neuchâtel. Material and methodsThe data were abstracted from the Vaud and Neuchâtel Cancer Registries files, which include incident cases of malignant neoplasms in the cantons, 6,7 whose populations, according to the December 2000 National Census, were about 620,000 and 166,000, respectively. In these cantons, population-based incidence data have been available since 1974. The registries are tumor-based, and multiple primaries in the same person are entered separately. The information available comprises sociodemographic characteristics of the patient (i.e., age, sex), primary site and histologic type of the tumor according to the International Classification of Diseases for Oncology (ICD-O), 8 as well as date of diagnostic confirmation (histologic or clinical diagnosis).The present series comprises 3,439 histologically confirmed first CMM ) and m...

Ambient UV, personal sun exposure and risk of multiple primary melanomas

“…While the relative risks of the major measures of personal sun exposure for multiple primary melanomas are similar to those for a first or any melanoma, the absolute risks conferred by equivalent levels of exposure will be quite different, because the absolute risk of a subsequent melanoma in a person who has already had a melanoma is some 2-4 times greater than that of a first melanoma in an otherwise similar person [1,17]. Minimizing sun exposure might, therefore, be of particular value in reducing risk of multiple primary melanomas.…”

“…People who have had one melanoma have an important risk of a second, estimated at an average of 1% a year [1]. Studies of risk of multiple primary melanomas have been concerned mainly with influences of the previous history of melanoma, presence of dysplastic nevi, or possible genetic susceptibility [2][3][4].…”

The incidence of second primary invasive melanoma in Queensland, 1982–2003

“…While surveillance is obviously motivated by the risk of recurrence, this risk diminishes within a few years of diagnosis [13]. Two studies, however, have found that the risk of a second primary melanoma does not decline with time [11,14].…”

Melanoma Epidemiology, Risk Factors, and Clinical Phenotypes

“…Risk of a second primary cutaneous melanoma among melanoma patients is found to be 6.01 per 1,000 person years after analysis of 20 years of follow-up in Queensland from 1982(McCaul et al, 2008. Analysis of a Swiss registry found the 20-year incidence of second primary melanoma to be 5% (Levi et al, 2005). A retrospective study of patients with multiple primary melanomas identified several risk factors for multiple melanomas such as early age at diagnosis, dysplastic nevi (diagnosed clinically or histologically), family history of dysplastic nevi or melanoma, and history of dysplastic nevus with a family history of melanoma (Stam-Posthuma et al, 2001).…”