RXRA and neoplasm: Immunohistochemical staining for β-catenin, cellular retinoic acid binding protein 1 (CRABP1), cellular retinoic acid binding protein 2 (CRABP2), fatty acid-binding protein 5 (FABP5), retinoic acid receptors (RAR-α, −β, −γ), and retinoid X receptors (RXR-α, −β, −γ) was performed on tissue samples obtained from tumor excision.