CA9 and neoplasm: Clinical features (performance status and hypertension), tumor profile (proneural subtype, VEGF, VEGFR, and carbonic anhydrase IX expression), tumor mutational status (TP53, IDH1, MGMT, and 1p19q codeletion), and circulating biomarkers (matrix metalloproteinases 2 and 9) have been reported as possible bevacizumab efficacy biomarkers in malignant glioma (25–33).