Davelaar et al. added fluorescent in situ hybridization (FISH) analysis of p53 to IHC to improve the ability to detect p53 abnormalities and thus prognostic ability in a cohort of 91 patients, including n = 80 non-progressors (BO patients diagnosed with at most LGD following minimum 3 years surveillance) and n = 11 progressors (BO/LGD to HGD/OAC) [20]. This evidence concerns the gene TP53 and bronchiolitis obliterans syndrome.