New malignancies after squamous cell carcinoma and melanomas: a population-based study from Norway

Abstract

BackgroundSkin cancer survivors experience an increased risk for subsequent malignancies but the associated risk factors are poorly understood. This study examined the risk of a new primary cancer following an initial skin cancer and assessed risk factors associated with second primary cancers.MethodsAll invasive cutaneous malignant melanomas (CMM, N = 28 069) and squamous cell carcinomas (SCC, N = 24 620) diagnosed in Norway during 1955–2008 were included. Rates of new primary cancers in skin cancer survivors were compared to rates of primary malignancies in the general population using standardized incidence ratios (SIR). Discrete-time logistic regression models were applied to individual-level data to estimate cancer risk among those with and without a prior skin cancer, accounting for residential region, education, income, parenthood, marital status and parental cancer status, using a 20% random sample of the entire Norwegian population as reference. Further analyses of the skin cancer cohort were undertaken to determine risk factors related to subsequent cancers.ResultsDuring follow-up, 9608 new primary cancers occurred after an initial skin cancer. SIR analyses showed 50% and 90% increased risks for any cancer after CMM and SCC, respectively (p < 0.01). The logistic regression model suggested even stronger increase after SCC (130%). The highest risk was seen for subsequent skin cancers, but several non-skin cancers were also diagnosed in excess: oral, lung, colon, breast, prostate, thyroid, leukemia, lymphoma and central nervous system. Factors that were associated with increased risk of subsequent cancers include male sex, older age, lower residential latitude, being married and low education and income. Parental cancer did not increase the risk of a subsequent cancer after SCC, but was a significant predictor among younger CMM survivors.ConclusionsOur results provide information on shared environmental and genetic risk factors for first and later cancers and may help to identify individuals at high risk for subsequent cancers, which will be important as skin cancer incidence continues to rise.

Risk of Second Malignancies in Solid Organ Transplant Recipients Who Develop Keratinocyte Cancers

“…Second, if cutaneous SCC were solely a marker of immunosuppression, we would expect to also see an increased risk of NHL after SCC, since risk of NHL is greatly increased with immunosuppression (28,29). Studies in the general population also have reported an increased risk of NHL after cutaneous SCC (6). In contrast, we found a decreased risk of NHL after cutaneous SCC.…”

Meta-Analyses of Epidemiologic Associations between Cutaneous Melanoma and Thyroid Cancer

“…Three found no statistically significant difference in overall risk in men versus women [5,7,9]. Another found a statistically significantly higher SIR of 2.78 (1.61-4.80) in men in contrast to a non-statistically significant SIR of 1.27 (0.81-1.99) in women [13]. Similarly, in studies that stratified risk by age of CM diagnosis, no differences were found [6,7,9].…”

“…Among the ten studies, two reported RR, seven reported SIR, and one reported odds ratio (OR). A statistically significantly increased risk of TC after CM diagnosis with a risk ratio ranging from 1.75 to 3.6 was reported in all studies except for one in Denmark [5][6][7][8][10][11][12][13][14]. Four studies stratified risk by gender.…”

“…The majority were U.S. studies that utilized the cancer registry records from the Surveillance, Epidemiology, and End Results (SEER) database of the National Cancer Institute in North America, including a study that analyzed the Connecticut registry, which also contributes to the SEER database [5][6][7][8][9][10][11][12][13]. One population-based study was from Utah [14,15].…”

“…The non-U.S. studies included one from Denmark, one from Norway, and another that included thirteen population-based cancer registries from Europe, Canada, Australia, and Singapore [8,9,13]. Of the ten studies that analysed TC subsequent to CM diagnosis, six included subjects with primary invasive melanoma only, two included both invasive melanoma and melanoma in-situ (MIS), and the remainder did not specify CM type [5][6][7][8][9][10][11][12][13][14]. Most subjects were White, with a mean age at CM diagnosis ranging from 52 years to 54 years.…”