Two genes remained significant in variant of a multivariate model that did not account for tumor stage: ERCC1 (RR = 0.53, 95% CI 0.30–0.96, p = 0.03) and CA9 (RR = 1.79, 95% CI 1.00–3.21, p = 0.05). Here, CA9 is linked to neoplasm.