The Association Between Socioeconomic Status, Renal Cancer Presentation, and Survival in the United States: A Survival, Epidemiology, and End Results Analysis

ObjectiveTo determine whether socioeconomic status (SES) predicts the size and local extent of tumors at presentation, and if this association leads to differences in survival.Materials and MethodsThe National Cancer Institute's Survival, Epidemiology, and End Results registry was queried for patients diagnosed with renal cancers between 2004 and 2010. Demographic, tumor, survival, and socioeconomic data were obtained. Cancers with T0 classification, nonrenal cell histology, or missing clinical or pathologic data were excluded. An SES measure was created from available metrics. Outcomes analyzed were tumor size, TNM classifications at diagnosis, tumor grade and histology subtype, and survival duration.ResultsA total of 40,212 cases were identified. On regression modeling, lower SES was an independent risk factor for tumor size ≥4 cm (P = .003) and for T classification ≥T2 (P = .040) at presentation, but did not predict histology subtype, positive lymph nodes, or metastasis. Lower SES predicted high-grade disease on univariate analysis (P = .012) but lost significance in the multivariate model. Lower SES was also independently predictive of shortened cancer-specific survival on multivariate analysis after adjusting for available cofactors (lowest vs highest SES quartile; P = .001).ConclusionThis study suggests that low SES is correlated with poorer survival outcomes in renal cancer, and this may be related to a tendency toward larger and more locally advanced tumors at diagnosis. Additional investigation is needed to ascertain whether these effects could be mediated by relatively lower rates of incidental detection via abdominal imaging in disadvantaged populations.