Chak, Amitabh

INTRODUCTION: Ablation of Barrett's esophagus (BE) is the preferred approach for the treatment of neoplasia without visible lesions. Limited data on cryoballoon ablation (CBA) suggest its potential clinical utility. We evaluated the safety and efficacy of CBA in a multicenter study of patients with neoplastic BE. METHODS: In a prospective clinical trial, 11 academic and community centers recruited consecutive patients with BE of 1–6 cm length and low-grade dysplasia, high-grade dysplasia (HGD), or intramucosal adenocarcinoma (ImCA) confirmed by central pathology. Patients with symptomatic pre-existing strictures or visible BE lesions had dilation or endoscopic mucosal resection (EMR), respectively, before enrollment. A nitrous oxide cryoballoon focal ablation system was used to treat all visible columnar mucosa in up to 5 sessions. Study end points included complete eradication of all dysplasia (CE-D) and intestinal metaplasia (CE-IM) at 1 year. RESULTS: One hundred twenty patients with BE with ImCA (20%), HGD (56%), or low-grade dysplasia (23%) were enrolled. In the intention-to-treat analysis, the CE-D and CE-IM rates were 76% and 72%, respectively. In the per-protocol analysis (94 patients), the CE-D and CE-IM rates were 97% and 91%, respectively. Postablation pain was mild and short lived. Fifteen subjects (12.5%) developed strictures requiring dilation. One patient (0.8%) with HGD progressed to ImCA, which was successfully treated with EMR. Another patient (0.8%) developed gastrointestinal bleeding associated with clopidogrel use. One patient (0.8%) had buried BE with HGD in 1 biopsy, not confirmed by subsequent EMR. DISCUSSION: In patients with neoplastic BE, CBA was safe and effective. Head-to-head comparisons between CBA and other ablation modalities are warranted (clinicaltrials.gov registration NCT02514525).

INTRODUCTION: While esophagectomy is the standard treatment for submucosal (T1b) esophageal adenocarcinoma (EAC) and squamous cell cancer (SCC), many elderly patients -the age group that esophageal cancer tends to affect- are not candidates for surgery. Endoscopic submucosal dissection (ESD) is a minimally invasive procedure that allows for en-bloc resection of early esophageal cancer and allows for precise histopathologic staging of the tumor. ESD could be curative in submucosal cancer without lymph node metastasis, and it allows for precise histopathologic staging. To evaluate the long-term outcomes of ESD in patients with EUS-staged T1b esophageal cancer. METHODS: A retrospective multicenter study was performed at three academic hospitals in the U.S. Patients who underwent ESD with a pre-procedural or post-procedural histopathologic diagnosis of T1b N0 M0 EAC or SCC were included in the study. Data was collected on demographics, tumor and procedure characteristics, procedure pathology, and follow-up. Local recurrence was confirmed by endoscopic findings and pathological analysis. Metastasis was confirmed by cross-sectional imaging. The main outcome was a composite of rate of metastasis and local recurrence. Follow-up time was defined as months from initial procedure to recurrence or last follow-up visit if recurrence-free. A time-to-event analysis was performed to evaluate recurrence. RESULTS: Fifty-two patients underwent ESD (mean age 69.6 years +/-9; 35 males) (Table 1). Based on available comorbidity data, 42% patients were not fit for surgery, as determined by an age-adjusted Charlson Comorbidity Index > 6. Twenty tumors (62%) were found to be HGD or T1a on post-ESD specimen analysis, while one was staged as T2. Nineteen patients were staged as T1b after ESD. Immediately after ESD, 6 patients were referred for surgery, 3 underwent chemoradiation therapy, and 6 radiation alone (Table 2). Patients were followed for a median of 18 months, and the calculated 24-month recurrence rate was 13% (Figure 1). CONCLUSION: This multicenter trial showed that ESD for T1b esophageal cancer can be acceptable for patients who deemed not surgical candidates. However, close follow up is necessary. ESD can also serve as a staging procedure, as our data confirms inaccurate EUS-staging of T1b cancer, with 62% of tumors being down-staged to T1a, as has been previously reported.

INTRODUCTION: The difference in long-term outcomes of endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) for Barrett’s related superficial neoplasia remains unclear. We aimed to compare the rates of local and metachronous recurrence of ESD and EMR in patients with clinically staged BE-associated high-grade dysplasia (HGD) and T1a esophageal adenocarcinoma (EAC). METHODS: Multicenter study at six academic hospitals in the U.S. including patients who underwent ESD for BE-HGD or T1a EAC. Primary outcome was a composite of metastasis and local recurrence rate. A time-to-event analysis was performed to evaluate recurrence. A Kaplan-Meier plot was constructed, and a log-rank test was used to compare the groups. A Cox hazard ratio regression analysis was performed to identify predictors of recurrence. RESULTS: A total of 241 patients were included. 154 underwent EMR, while 84 underwent ESD (Table 1). ESD had higher en bloc (96% vs 33%, P < 0.0001), R0 (76% vs 54%, P = 0.0009) and curative resection rates (75% vs 32%, P < .0001) when compared to EMR. The 24-month local recurrence rate for EMR and ESD was 43% and 11%, respectively ( P = 0.0007) (Figure 1). Significantly more endoscopic resection procedures were required to treat recurrence after EMR compared to after ESD (Table 1). EMR, piecemeal resection, positive margins, and non-curative resection were identified as predictors of recurrence on univariate analysis. En bloc resection remained significant after multivariate analysis (Table 2). CONCLUSION: This multicenter study showed that ESD results in more definitive treatment of BE-associated early neoplasia than EMR, with significant lower recurrence rates and less need for repeat endoscopic therapeutic procedures than EMR.

Combining DNA methylation markers with a swallowable device for sampling the distal esophagus effectively detects Barrett’s neoplasias.

Abstract Esophageal adenocarcinoma is a deadly cancer with increasing incidence in the United States, but mechanisms underlying pathogenesis are still mostly elusive. In addressing this question, we assessed gene fusion landscapes by comprehensive RNA sequencing (RNAseq) of 55 pretreatment esophageal adenocarcinoma and 49 nonmalignant biopsy tissues from patients undergoing endoscopy for Barrett's esophagus. In this cohort, we identified 21 novel candidate esophageal adenocarcinoma–associated fusions occurring in 3.33% to 11.67% of esophageal adenocarcinomas. Two candidate fusions were selected for validation by PCR and Sanger sequencing in an independent set of pretreatment esophageal adenocarcinoma (N = 115) and nonmalignant (N = 183) biopsy tissues. In particular, we observed RPS6KB1–VMP1 gene fusion as a recurrent event occurring in approximately 10% of esophageal adenocarcinoma cases. Notably, esophageal adenocarcinoma cases harboring RPS6KB1–VMP1 fusions exhibited significantly poorer overall survival as compared with fusion-negative cases. Mechanistic investigations established that the RPS6KB1–VMP1 transcript coded for a fusion protein, which significantly enhanced the growth rate of nondysplastic Barrett's esophagus cells. Compared with the wild-type VMP1 protein, which mediates normal cellular autophagy, RPS6KB1–VMP1 fusion exhibited aberrant subcellular localization and was relatively ineffective in triggering autophagy. Overall, our findings identified RPS6KB1–VMP1 as a genetic fusion that promotes esophageal adenocarcinoma by modulating autophagy-related processes, offering new insights into the molecular pathogenesis of esophageal adenocarcinomas. Cancer Res; 76(19); 5628–33. ©2016 AACR.

AbstractBackgroundFamilial aggregation and segregation analysis studies have provided evidence of a genetic basis for esophageal adenocarcinoma (EAC) and its premalignant precursor, Barrett's esophagus (BE). We aim to demonstrate the utility of linkage analysis to identify the genomic regions that might contain the genetic variants that predispose individuals to this complex trait (BE and EAC).MethodsWe genotyped 144 individuals in 42 multiplex pedigrees chosen from 1000 singly ascertained BE/EAC pedigrees, and performed both model‐based and model‐free linkage analyses, using S.A.G.E. and other software. Segregation models were fitted, from the data on both the 42 pedigrees and the 1000 pedigrees, to determine parameters for performing model‐based linkage analysis. Model‐based and model‐free linkage analyses were conducted in two sets of pedigrees: the 42 pedigrees and a subset of 18 pedigrees with female affected members that are expected to be more genetically homogeneous. Genome‐wide associations were also tested in these families.ResultsLinkage analyses on the 42 pedigrees identified several regions consistently suggestive of linkage by different linkage analysis methods on chromosomes 2q31, 12q23, and 4p14. A linkage on 15q26 is the only consistent linkage region identified in the 18 female‐affected pedigrees, in which the linkage signal is higher than in the 42 pedigrees. Other tentative linkage signals are also reported.ConclusionOur linkage study of BE/EAC pedigrees identified linkage regions on chromosomes 2, 4, 12, and 15, with some reported associations located within our linkage peaks. Our linkage results can help prioritize association tests to delineate the genetic determinants underlying susceptibility to BE and EAC.

Abstract Background: Barrett's esophagus is often asymptomatic and only a small portion of Barrett's esophagus patients are currently diagnosed and under surveillance. Therefore, it is important to develop risk prediction models to identify high-risk individuals with Barrett's esophagus. Familial aggregation of Barrett's esophagus and esophageal adenocarcinoma, and the increased risk of esophageal adenocarcinoma for individuals with a family history, raise the necessity of including genetic factors in the prediction model. Methods to determine risk prediction models using both risk covariates and ascertained family data are not well developed. Methods: We developed a Barrett's Esophagus Translational Research Network (BETRNet) risk prediction model from 787 singly ascertained Barrett's esophagus pedigrees and 92 multiplex Barrett's esophagus pedigrees, fitting a multivariate logistic model that incorporates family history and clinical risk factors. The eight risk factors, age, sex, education level, parental status, smoking, heartburn frequency, regurgitation frequency, and use of acid suppressant, were included in the model. The prediction accuracy was evaluated on the training dataset and an independent validation dataset of 643 multiplex Barrett's esophagus pedigrees. Results: Our results indicate family information helps to predict Barrett's esophagus risk, and predicting in families improves both prediction calibration and discrimination accuracy. Conclusions: Our model can predict Barrett's esophagus risk for anyone with family members known to have, or not have, had Barrett's esophagus. It can predict risk for unrelated individuals without knowing any relatives' information. Impact: Our prediction model will shed light on effectively identifying high-risk individuals for Barrett's esophagus screening and surveillance, consequently allowing intervention at an early stage, and reducing mortality from esophageal adenocarcinoma. Cancer Epidemiol Biomarkers Prev; 25(5); 727–35. ©2016 AACR.