P53 status identifies BE patients at risk of progression

Abnormal p53 immunohistochemical (IHC) findings may indicate a higher risk of progression in Barrett’s oesophagus (BE) patients, a new study has found.

To develop a p53 IHC scoring criteria, researchers first conducted a retrospective assessment of endoscopy samples from patients diagnosed with nondysplastic BE (NDBE), BE indefinite for dysplasia (BE-IND), or BE with low-grade dysplasia (BE-LGD), comparing between those with vs without progression to oesophageal carcinoma (EAC) or BE with high-grade dysplasia (BE-HGD).

The resulting score showed good performances, such that of 50 unselected biopsies, abnormal p53 staining was observed in 96 percent of BE-HGD samples and only 4 percent of NDBE samples. Moreover, the p53 IHC score showed a 96-percent sensitivity and 83.3-percent specificity for identifying TP53 mutations.

Notably, the p53 IHC score could predict progression independent of the initial histologic diagnosis. For instance, among patients with NDBE, BE-IND, and BE-LGD, 49.7 percent, 90.0 percent, and 94.2 percent of progressors to advanced disease showed p53 abnormalities at baseline endoscopy.

Similar patterns were observed in an independent, case-control testing cohort of 1,438 participants. Baseline endoscopy samples with abnormal p53 staining had a sensitivity of 50.8 percent and specificity of 98.3 percent for predicting progress. The corresponding odds ratio was 58 (95 percent confidence interval, 17.9–188.5; p<0.0001). Such predictive capacity remained strong even when stratifying according to baseline histology.

“In light of past studies, we feel that obtaining our results under these ‘real world’ conditions strongly support the robustness and reproducibility of using p53 IHC,” the researchers said.