Risk Factors for Malignant Melanoma and Preventive Methods
UV radiation is an important environmental risk factor for cutaneous melanoma; however, information concerning UV exposure in many populations is lacking. The aim of our study was to investigate risk factors for malignant melanoma (MM), particularly those related to UV exposure behavior in the Czech Republic and Germany. This case-control study included 207 patients who were consecutively diagnosed with MM in 2 dermatology clinics in Prague, Czech Republic, and Munich, Germany. Controls were 235 patients with other dermatologic conditions. All 442 participants completed a questionnaire on sociodemographic data and factors related to UV exposure. The association between risk factors and MM was assessed using multivariate logistic regression. Patients with Fitzpatrick skin types I and II had a higher likelihood of developing melanoma than those with Fitzpatrick skin type III. Frequent sunburns during childhood and adolescence were strongly related to developing melanoma. A higher level of education also was associated with a higher melanoma incidence. Variables related to UV exposure were strongly associated with melanoma in our study population. Prevention campaigns should be implemented to improve awareness of melanoma to reduce exposure to UV radiation among high-risk patient populations.
Practice Points
- Our study revealed the following common risk factors associated with higher melanoma incidence: light eye color (ie, blue, green, gray), Fitzpatrick skin types I and II, frequent sunburns during childhood and adolescence, and higher level of education.
- Prevention campaigns should be implemented to improve awareness of melanoma to reduce exposure to UV radiation among high-risk patient populations.
Biological Model
Eye color and Fitzpatrick skin type were the focus of the biological model. The odds of being diagnosed with melanoma were 2.5 times greater in respondents with a light eye color (ie, blue, green, gray) than in respondents with a dark eye color (ie, brown, black). Respondents with Fitzpatrick skin types I and II had a significantly higher association with melanoma (OR, 4.25 and 6.98; 95% CI, 2.13-8.51 and 3.78-12.88) than Fitzpatrick skin type III (OR, 1.0)(P<.001 for both). Respondents with darker skin types (IV and V) also were present in our study population. The numbers were low, and the CI was too wide; nevertheless, the results were statistically significant (P<.001).
Lifestyle Model
The lifestyle model included patients’ use of sunscreen and level of sun exposure at work and on vacation. Respondents who did not use sunscreen were 12 times more likely to develop melanoma than those who always used it (95% CI, 5.56-27.14); however, individuals who used sunscreen always and repetitively (ie, more than once during 1 period of sun exposure) had a higher likelihood of melanoma compared to those who always used it. The incidence of melanoma was lower in respondents who regularly spent their vacations by the sea than those who did not vacation in seaside regions. Respondents who worked in direct sunlight were approximately 2 times more likely to present with melanoma than individuals who did not work outside.
Exposure Model
The number of sunburns sustained during childhood and adolescence was assessed in the exposure model. Respondents with a history of 1 to 5 sunburns during childhood and adolescence did not show a statistically significant increase in the incidence of melanoma diagnosis; however, those with a history of 6 or more sunburns during these periods showed a significant increase in the odds of developing melanoma (OR, 4.95 and 25.52; 95% CI, 2.29-10.71 and 12.16-53.54)(P<.001 for both).
