Sociodemographic Disparities in Melanoma Stage at Diagnosis: The Role of Socioeconomic Status and Residential Location.

Background: Low tumour stage is associated with improved prognosis following diagnosis of primary melanoma. This study evaluated the associations between patient socioeconomic status (SES) and location of residence on tumour stage at melanoma diagnosis.

Methods: Patients with a new diagnosis of histologically confirmed T1b-T4b melanoma in Queensland, Australia were recruited between 2010-2014. Logistic regression models were used to assess whether SES or location of residence were associated with lower (T1b-T3a) versus higher tumour stage (≥T3b).

Results: Of 700 study participants with melanoma, those living in lower SES areas (n=358) had a higher likelihood of being diagnosed with ≥T3b-stage disease compared to patients in higher SES areas (n=342) (adjusted odds ratio [aOR] = 1.65, 95% confidence interval [CI]: 1.04-2.62, P =0.03). Relative to patients living in urban areas (n=389), patients living in inner regional areas (n=209) were more likely to be diagnosed with a ≥T3b-stage melanoma (OR = 1.65; 95% CI: 1.11-2.46; P = 0.01); however, this finding was not significant following adjustment for SES (aOR 1.17, 95% CI 0.72-1.91; P = 0.53).

Conclusions: Patients residing in areas with lower average socioeconomic advantage were more frequently diagnosed with a locally advanced melanoma than patients in high SES areas. Geographical remoteness was not independently associated with tumour stage at diagnosis in this cohort.

Impact: Our study highlights a disparity in early melanoma detection across socioeconomic classes. Population groups who are disproportionately more likely to be diagnosed with a thicker primary melanoma should be considered for targeted screening initiatives and healthcare accessibility programs.