T. Lal2,3, W. Dong1,2, N.N. Chakraborty2,3, L.D. Rothermel2,3,4, R.S. Hoehn2,3,4 1Case Western Reserve University School Of Medicine, Department Of Population And Quantitative Health Sciences, Cleveland, OH, USA 2Case Western Reserve University School Of Medicine, Cleveland, OH, USA 3Case Western Reserve University Hospitals, Division Of Surgical Oncology, Cleveland, OH, USA 4Case Comprehensive Cancer Center, Cleveland, OH, USA
Introduction:
Previous studies have correlated high socioeconomic status (SES) with increased early-stage melanoma diagnoses but not necessarily lower late-stage diagnoses. While these studies have been limited to local datasets, our study shifts to examining this at a national level. We investigate the association between early- and late-stage melanoma diagnoses with a broader scope of social determinants of health (SDoH), as measured by the social vulnerability index (SVI), and other common melanoma risk factors.
Methods:
Using data from the 2004-2021 Surveillance, Epidemiology, and End Results (SEER) database, we identified a total of 829,391 non-Hispanic White patients: 725,077 with early-stage disease (melanoma in situ and localized) and 104,314 with late-stage disease (regional and distant). County-level SVI scores, a composite of 15 SDoH domains, were extracted from the CDC (2018). Univariate linear regression models assessed the relationship between SVI and disease incidence for melanoma overall and by stage, with scatterplots to illustrate the findings. Further analyses examined the association between melanoma incidence and rural/urban status, agricultural employment, and UV index, with box plots created for each of these variables.
Results:
Increasing SVI was negatively correlated with the overall incidence of melanoma (r = -0.15, p<0.05). In stage-specific analyses, higher social vulnerability correlated with a lower incidence of early-stage melanoma (r = -0.38, p <0.001), but there was no association between SVI and late-stage melanoma (r = 0, p=0.965, Figure 1). Urban areas exhibited a higher incidence of early-stage melanoma compared to rural areas, though this pattern did not extend to late-stage disease. Neither early- nor late-stage melanoma incidence was associated with agricultural employment rates or UV exposure levels across SEER counties.
Conclusion:
Higher social vulnerability is linked to a lower incidence of early-stage melanoma without a commensurate increase in late-stage melanoma, suggesting potential overdiagnosis of biologically indolent early-stage melanomas among more affluent patients. Other possible risk factors (rurality, agricultural employment, UV exposure) were not correlated with melanoma incidence. These findings suggest that unknown biologic factors have a greater influence on melanoma mortality than dermatology outreach and screening programs.