Sun protection behavior after diagnosis of high-risk primary melanoma and risk of a subsequent primary

Background: Melanoma survivors are at high risk of further primary melanomas. Objective: To assess sun behavior after melanoma diagnosis and in relation to further primary melanomas. Methods: We applied repeated measures latent class analysis to reported primary prevention behavior at time of diagnosis and every 6 months for 2 years after diagnosis in patients with clinical stage IB or II melanoma. Correlates of behavior trajectories and risk of subsequent primaries were determined by using multivariable logistic and Cox regression analyses, respectively. Results: Among the 448 male and 341 female patients, sunscreen use fell into 3 trajectories: stable neveruse (26% of males and 12% of females), stable sometimes-use (35% of males and 29% of females), and increased to often-use (39% of males and 59% of females). Most reduced their weekend sun exposure, but in 82% of males and 69% of females it remained increased. Males, smokers, the less educated, those who tanned, and those not self-checking their skin were more likely to have trajectories of inadequate protection. Patients with a history of melanoma before the study doubled their risk of another primary melanoma in the next 2 years if sunscreen use in that time was inadequate (hazard ratio, 2.45; 95% confidence interval, 1.00-6.06). Limitations: Patient-reported data are susceptible to recall bias. Conclusion: Our results may assist clinicians in identifying patients not using adequate sun protection and providing information for patient counseling.