Stachler, Matthew D

INTRODUCTION: The adjunctive use of p53 immunohistochemistry has been proposed as a potential tool to improve risk stratification in Barrett's esophagus (BE) with conflicting results. We performed a systematic review and meta-analysis to evaluate the performance of p53 in predicting progression to advanced neoplasia (high-grade dysplasia [HGD] and esophageal adenocarcinoma [EAC]) among patients with BE. METHODS: We searched multiple databases for studies that evaluated the use of aberrant p53 in esophageal biopsies among patients with BE and reported progression rates to HGD/EAC. The outcomes were p53 test characteristics and incidence and risk ratio (RR) for progression to HGD/EAC in patients with and without aberrant p53 using random effects models. RESULTS: Among the 27 included studies, the proportion of patients with aberrant p53 expression at baseline was 20% (95% CI: 14%, 27%). The rate of progression with and without aberrant p53 was 8 per 100 person-years (95% CI: 6, 11) and 0.3 per 100 person-years (95% CI: 0.1, 0.6), respectively. Compared with patients without aberrant p53 expression, those with aberrant p53 had a higher risk for progression to HGD/EAC in cohort studies (RR = 10.2 [95% CI: 6.9, 15.0]) and case control studies (RR = 3.3 [95% CI: 2.5, 4.4]). The sensitivity for progression for non-dysplastic Barrett's esophagus and low-grade dysplasia/indefinite for dysplasia was 42% and 77% and specificity was 96% and 76%, respectively. DISCUSSION: While aberrant p53 expression has been associated with an increased risk of progression to advanced neoplasia in patients with BE undergoing surveillance, the diagnostic characteristics are suboptimal precluding uniform clinical adoption. Prospective studies with standardized grading protocols are needed to determine whether p53-guided surveillance strategies can meaningfully improve patient outcomes.

INTRODUCTION: Early neoplastic progression of Barrett's esophagus (BE) is often treated with endoscopic therapy. Although effective, some patients are refractory to therapy or recur after apparent eradication of the BE. The goal of this study was to determine whether genomic alterations within the treated BE may be associated with persistent or recurrent disease. METHODS: We performed DNA sequencing on pre-treatment esophageal samples from 45 patients who were successfully treated by endoscopic therapy and did not recur as well as pre-treatment and post-treatment samples from 40 patients who had persistent neoplasia and 21 patients who had recurrent neoplasia. The genomic alterations were compared between groups. RESULTS: The genomic landscape was similar between all groups. Patients with persistent disease were more likely to have pre-treatment alterations involving the receptor tyrosine kinase pathway ( P = 0.01), amplifications of oncogenes ( P = 0.01), and deletions of tumor suppressor genes ( P = 0.02). These associations were no longer significant after adjusting for patient age and BE length. More than half of patients with persistent (52.5%) or recurrent (57.2%) disease showed pre-treatment and post-treatment samples that shared at least 50% of their driver mutations. DISCUSSION: Pre-treatment samples were genomically similar between those who responded to endoscopic therapy and those who had persistent or recurrent disease, suggesting there is not a strong genomic component to treatment response. Although it was expected to find shared driver mutations in pre-treatment and post-treatment samples in patients with persistent disease, the finding that an equal number of patients with recurrent disease also showed this relation suggests that many recurrences represent undetected minimal residual disease.