Bruce D. Greenwald

Inactivation of p16, RUNX3, and HPP1 occurs early in Barrett's-associated neoplastic progression and predicts progression risk

Patients with Barretts esophagus (BE) are at increased risk of developing esophageal adenocarcinoma (EAC). Clinical neoplastic progression risk factors, such as age and the length of the esophageal BE segment, have been identified. However, improved molecular biomarkers predicting increased progression risk are needed for improved risk assessment and stratification. Using real-time quantitative methylation-specific PCR, we screened 10 genes (HPP1, RUNX3, RIZ1, CRBP1, 3-OST-2, APC, TIMP3, p16, MGMT, p14) for promoter hypermethylation in 77 EAC, 93 BE, and 64 normal esophagus (NE) specimens. A subset of genes manifesting significant differences in methylation frequencies between BE and EAC was then analysed in 20 dysplastic specimens. All 10 genes except p14 were frequently methylated in EACs, with RUNX3, HPP1, CRBP1, RIZ1, and OST-2 representing novel methylation targets in EAC and/or BE. p16, RUNX3, and HPP1 displayed increasing methylation frequencies in BE vs EAC. Furthermore, these increases in methylation occurred early, at the interface between BE and low-grade dysplasia (LGD). To demonstrate the silencing effect of hypermethylation, we selected the EAC cells BIC1, in which the HPP1 promoter is natively methylated, and subjected them to 5-aza-2′-deoxycytidine (Aza-C) treatment. Real-time RT–PCR indicated increased HPP1 mRNA levels after 3 days of Aza-C treatment, as well as decreased levels of methylated HPP1 DNA. Hypermethylation of a subset of six genes (APC, TIMP3, CRBP1, p16, RUNX3, and HPP1) was then tested in a retrospective longitudinal study of 99 BE and nine LGD specimens obtained from 53 BE patients undergoing surveillance endoscopy. Only high-grade dysplasia (HGD) or EAC were defined as progression end points. Two patient groups were compared: eight progressors (P) and 45 nonprogressors (NP), using Cox proportional hazards models to determine the relative progression risks of age, BE segment length, and methylation events. Multivariate analyses revealed that only hypermethylation of p16 (odds ratio (OR) 1.74, 95% confidence interval (CI) 1.33–2.20), RUNX3 (OR 1.80, 95% CI 1.08–2.81), and HPP1 (OR 1.77, 95% CI 1.06–2.81) were independently associated with an increased risk of progression, whereas age, BE segment length, and hypermethylation of TIMP3, APC, or CRBP1 were not independent risk factors. In combined analyses, risk was detectable up to, but not earlier than, 2 years preceding neoplastic progression. Hypermethylation of p16, RUNX3, and HPP1 in BE or LGD may represent independent risk factors for the progression of BE to HGD or EAC. These findings have implications regarding risk stratification, early EAC detection, and the appropriate endoscopic surveillance interval for patients with BE.

p53 Point mutations in dysplastic and cancerous ulcerative colitis lesions

BACKGROUND The molecular basis of colorectal dysplasia and carcinoma arising in ulcerative colitis is poorly understood. Loss of heterozygosity involving the tumor suppressor gene p53 occurs frequently in neoplastic ulcerative colitis lesions. Point mutation affecting p53 is associated with loss of heterozygosity in other cancers. Therefore, it was determined whether p53 point mutation occurs in ulcerative colitis-associated neoplasia. METHODS Single-strand conformation polymorphism analysis, DNA sequencing, and loss of heterozygosity studies were performed on 45 patients with ulcerative colitis-associated dysplasia and carcinoma. RESULTS Point mutations were detected in 26 lesions from 20 patients, including 18 carcinomas, 6 dysplasia-associated masses, 1 flat dysplasia, and 1 lymph node metastasis. In two cases, identical p53 mutations were observed in both carcinoma and adjacent dysplasia. Missense mutations causing amino acid substitutions as well as nonsense mutations resulting in premature stop codons were seen. Tandem mutations, in which more than 1 sequence alteration occurred on the same allele of p53, were also detected. Point mutation was accompanied by loss of the other p53 allele in 8 of 10 patients informative for both loss of heterozygosity and mutation assays. CONCLUSIONS These findings suggest that inactivation of p53 by mutation and loss of heterozygosity is a common mechanism of malignant transformation in ulcerative colitis. They also imply that in contrast to sporadic colorectal carcinoma, ulcerative colitis-associated neoplastic progression may involve p53 inactivation at relatively early, noninvasive stages.

Safety and efficacy of endoscopic spray cryotherapy for Barrett's esophagus with high-grade dysplasia.

BACKGROUND Endoscopic ablation to treat Barretts esophagus (BE) with high-grade dysplasia (HGD) is associated with a decreased incidence of esophageal adenocarcinoma. Endoscopic spray cryotherapy (CRYO) demonstrates promising preliminary data. OBJECTIVE To assess the safety and efficacy of CRYO in BE with HGD. DESIGN Multicenter, retrospective cohort study. SETTING Nine academic and community centers; treatment period, 2007 to 2009. PATIENTS Subjects with HGD confirmed by 2 pathologists. Previous EMR was allowed if residual HGD remained. INTERVENTIONS CRYO with follow-up biopsies. MAIN OUTCOME MEASUREMENTS Complete eradication of HGD with persistent low-grade dysplasia, complete eradication of all dysplasia with persistent nondysplastic intestinal metaplasia, and complete eradication of all intestinal metaplasia. RESULTS Ninety-eight subjects (mean age 65.4 years, 83% male) with BE and HGD (mean length 5.3 cm) underwent 333 treatments (mean 3.4 treatments per subject). There were no esophageal perforations. Strictures developed in 3 subjects. Two subjects reported severe chest pain managed with oral narcotics. One subject was hospitalized for bright red blood per rectum. Sixty subjects had completed all planned CRYO treatments and were included in the efficacy analysis. Fifty-eight subjects (97%) had complete eradication of HGD, 52 (87%) had complete eradication of all dysplasia with persistent nondysplastic intestinal metaplasia, and 34 (57%) had complete eradication of all intestinal metaplasia. Subsquamous BE was found in 2 subjects (3%). LIMITATIONS Nonrandomized, retrospective study with no control group, short follow-up (10.5 months), lack of centralized pathology, and use of surrogate outcome for decreased cancer risk. CONCLUSIONS CRYO is a safe and well-tolerated therapy for BE and HGD. Short-term results suggest that CRYO is highly effective in eradicating HGD.

Quality Assessment of Colonoscopic Cecal Intubation: An Analysis of 6 Years of Continuous Practice at a University Hospital

BACKGROUND:Despite increased emphasis on endoscopic performance indicators, e.g., cecal intubation rates, limited data from actual clinical practice have been published.OBJECTIVES:Retrospective database review to determine the rate and documentation of cecal intubation during colonoscopy at the University of Maryland Medical Center.METHODS:We reviewed 5,477 consecutive colonoscopies performed by 10 faculty gastroenterologists at a University hospital over a 6-yr period (March 1, 1999 to February 28, 2005). Unadjusted cecal intubation rates were analyzed as were rates that were adjusted based on the U.S. Multi-Society Task Force on Colorectal Cancer recommendations. We analyzed trends in overall and individual cecal intubation rates, circumstances that impact these rates, and the quality of documentation of cecal intubation.RESULTS:The overall adjusted cecal intubation rate for the entire 6 yr was 90.3%, and increased over the study period with the highest adjusted rate (93.7%) in the most recent year studied. There was no correlation between cecal intubation rate and patient age, gastroenterology fellow involvement, or endoscopist experience and number of procedures/year. In contrast, colon cancer screening, male gender, outpatient colonoscopy, and adequate bowel preparation predicted a higher cecal intubation rate. Written and photographic documentation of cecal intubation improved significantly after 2002.CONCLUSIONS:Our analysis revealed cecal intubation and documentation rates that meet current guidelines, and identified factors that may cause substantial variance in these rates depending on the nature of the practice. The present analysis confirms that computerized databases can be used to assess individual and group cecal intubation and documentation rates on an annual basis, and to make these data available to the public.

Global gene expression profiling in Barrett's esophagus and esophageal cancer: a comparative analysis using cDNA microarrays

In order to identify and contrast global gene expression profiles defining the premalignant syndrome, Barretts esophagus, as well as frank esophageal cancer, we utilized cDNA microarray technology in conjunction with bioinformatics tools. We hybridized microarrays, each containing 8000 cDNA clones, to RNAs extracted from 13 esophageal surgical or endoscopic biopsy specimens (seven Barretts metaplasias and six esophageal carcinomas). Hierarchical cluster analysis was performed on these results and displayed using a color-coded graphic representation (Treeview). The esophageal samples clustered naturally into two principal groups, each possessing unique global gene expression profiles. After retrieving histologic reports for these tissues, we found that one main cluster contained all seven Barretts samples, while the remaining principal cluster comprised the six esophageal cancers. The cancers also clustered according to histopathological subtype. Thus, squamous cell carcinomas (SCCAs) constituted one group, adenocarcinomas (ADCAs) clustered separately, and one signet-ring carcinoma was in its own cluster, distinct from the ADCA cluster. We conclude that cDNA microarrays and bioinformatics show promise in the classification of esophageal malignant and premalignant diseases, and that these methods can be applied to small biopsy samples.

Transcriptional profiling suggests that Barrett's metaplasia is an early intermediate stage in esophageal adenocarcinogenesis

To investigate the relationship between Barretts esophagus (BE) and esophageal adenocarcinoma (EAC), we determined gene expression profiles of discrete pathological stages of esophageal neoplasia using a sequence-verified human cDNA microarray. Fifty one RNAs, comprising 24 normal esophagi (NE), 18 BEs, and nine EACs were hybridized to cDNA microarrays. Five statistical analyses were used for the data analysis. Genes showing significantly different expression levels among the three sample groups were identified. Genes were grouped into functional categories based on the Gene Ontology Consortium. Surprisingly, the expression pattern of BE was significantly more similar to EAC than to NE, notwithstanding the known histopathologic differences between BE and EAC. The pattern of NE was clearly distinct from that of EAC. Thirty-six genes were the most differentially modulated, according to these microarray data, in BE-associated neoplastic progression. Twelve genes were significantly differentially expressed in cancer-associated BEs plus EAC (as a single combined tissue group) vs noncancer-associated BEs. These genes represent potential biomarkers to diagnose EAC at its early stages. Our results demonstrate that molecular events at the transcriptional level in BE are remarkably similar to BEs-associated adenocarcinoma of the esophagus. This finding alarmingly implies that BE is biologically closer to cancer than to normal esophagus, and that the cancer risk of BE is perhaps higher than we had imagined. These findings suggest that changes modulated at the molecular biologic level supervene earlier than histologic changes, and that BE is an early intermediate stage in the process of EAC.

Endoscopic spray cryotherapy for esophageal cancer: safety and efficacy

BACKGROUND Few options exist for patients with localized esophageal cancer ineligible for conventional therapies. Endoscopic spray cryotherapy with low-pressure liquid nitrogen has demonstrated efficacy in this setting in early studies. OBJECTIVE To assess the safety and efficacy of cryotherapy in esophageal carcinoma. DESIGN Multicenter, retrospective cohort study. SETTING Ten academic and community medical centers between 2006 and 2009. PATIENTS Subjects with esophageal carcinoma in whom conventional therapy failed and those who refused or were ineligible for conventional therapy. INTERVENTIONS Cryotherapy with follow-up biopsies. Treatment was complete when tumor eradication was confirmed by biopsy or when treatment was halted because of tumor progression, patient preference, or comorbid condition. MAIN OUTCOME MEASUREMENTS Complete eradication of luminal cancer and adverse events. RESULTS Seventy-nine subjects (median age 76 years, 81% male, 94% with adenocarcinoma) were treated. Tumor stage included T1-60, T2-16, and T3/4-3. Mean tumor length was 4.0 cm (range 1-15 cm). Previous treatment including endoscopic resection, photodynamic therapy, esophagectomy, chemotherapy, and radiation therapy failed in 53 subjects (67%). Forty-nine completed treatment. Complete response of intraluminal disease was seen in 31 of 49 subjects (61.2%), including 18 of 24 (75%) with mucosal cancer. Mean (standard deviation) length of follow-up after treatment was 10.6 (8.4) months overall and 11.5 (2.8) months for T1 disease. No serious adverse events were reported. Benign stricture developed in 10 (13%), with esophageal narrowing from previous endoscopic resection, radiotherapy, or photodynamic therapy noted in 9 of 10 subjects. LIMITATIONS Retrospective study design, short follow-up. CONCLUSIONS Spray cryotherapy is safe and well tolerated for esophageal cancer. Short-term results suggest that it is effective in those who could not receive conventional treatment, especially for those with mucosal cancer.

Endoscopic Ultrasound Does Not Accurately Stage Early Adenocarcinoma or High-Grade Dysplasia of the Esophagus

BACKGROUND & AIMS Patients with esophageal high-grade dysplasia or mucosal esophageal cancer can be successfully treated by endoscopy. We performed a systematic review of the literature to determine whether endoscopic ultrasound (EUS) correctly predicts the T-stage of early esophageal cancers, compared with pathology specimens obtained by using endoscopic mucosal resection (EMR) or surgery. METHODS Standard systematic review methods were used to perform reference searches, determine eligibility, abstract data, and analyze data. When possible, individual patient-level data were abstracted, in addition to publication-level aggregate data. RESULTS Twelve studies had sufficient information to abstract and review for quality; 8 had individual patient-level data (n = 132). Compared with surgical or EMR pathology staging, EUS had T-stage concordance of 65%, including all studies (n = 12), but only 56% concordance when limited to individual patient-level data. Factors such as initial biopsy pathology (high-grade dysplasia vs early-stage cancer) did not appear to affect the concordance of staging between EUS and EMR/surgical staging. CONCLUSIONS EUS is not sufficiently accurate in determining the T-stage of high-grade dysplasias or superficial adenocarcinomas; other means of staging, such as EMR, should be used.

Safety, tolerability, and efficacy of endoscopic low-pressure liquid nitrogen spray cryotherapy in the esophagus

Endoscopic cryotherapy is a new technique for ablation of esophageal dysplasia and neoplasia. Preliminary studies have shown it to be safe and effective for this indication. The objective of this study is to characterize safety, tolerability, and efficacy of low-pressure liquid nitrogen endoscopic spray cryotherapy ablation in a large cohort across multiple study sites. Parallel prospective treatment studies at four tertiary care academic medical centers in the U.S. assessed spray cryotherapy in patients with Barretts esophagus with or without dysplasia, early stage esophageal cancer, and severe squamous dysplasia who underwent cryotherapy ablation of the esophagus. All patients were contacted between 1 and 10 days after treatment to assess for side effects and complications of treatment. The main outcome measurement was the incidence of serious adverse events and side effects from treatment. Complete response for high-grade dysplasia (HGD) (CR-HGD), all dysplasia (CR-D), intestinal metaplasia (CR-IM) and cancer (CR-C) were assessed in patients completing therapy during the study period. A total of 77 patients were treated for Barretts high-grade dysplasia (58.4%), intramucosal carcinoma (16.9%), invasive carcinoma (13%), Barretts esophagus without dysplasia (9.1%), and severe squamous dysplasia (2.6%). Twenty-two patients (28.6%) reported no side effects throughout treatment. In 323 procedures, the most common complaint was chest pain (17.6%) followed by dysphagia (13.3%), odynophagia (12.1%), and sore throat (9.6%). The mean duration of any symptoms was 3.6 days. No side effects were reported in 48% of the procedures (155/323). Symptoms did not correlate with age, gender, diagnosis, or to treatment early versus late in the patients or sites experience. Logit analysis showed that symptoms were greater in those with a Barretts segment of 6 cm or longer. Gastric perforation occurred in one patient with Marfans syndrome. Esophageal stricture developed in three, all successfully treated with dilation. In 17 HGD patients, cryotherapy produced CR-HGD, CR-D, and CR-IM of 94%, 88%, and 53%, respectively. Complete regression of cancer and HGD was seen in all seven patients with intramucosal carcinoma or stage I esophageal cancer. Endoscopic spray cryotherapy ablation using low-pressure liquid nitrogen in the esophagus is safe, well-tolerated, and efficacious.

N-2-butyl-cyanoacrylate for bleeding gastric varices: a United States pilot study and cost analysis

OBJECTIVES:N-butyl-2-cyanoacrylate has been reported to be effective for bleeding varices but is not available in the United States. We report the initial US experience with cyanoacrylate in this prospective trial and evaluate its safety, efficacy, and relative costs.METHODS:Patients with active or recent gastric variceal bleeding were eligible. Cyanoacrylate therapy was performed until variceal occlusion was achieved. Rebleeding was assessed at 72 h (acute phase), 6 wk (subacute phase), and 1 yr (chronic phase). Survival was assessed at 3 months and 1 yr. Cost analysis was performed comparing the first 17 patients to historical control patients not treated with cyanoacrylate.RESULTS:A total of 44 patients were enrolled, 37 with cirrhosis and seven with noncirrhotic portal hypertension (NCPH). In cirrhotic patients, rebleeding was seen in two of 37 (5%) at 72 h, one of 30 (3%) at 6 wk, and five of 28 (18%) at 1 yr. Survival without shunt at 3 months was 30 of 34 (88%) and at 1 yr was 24 of 31 (77%). In NCPH patients, rebleeding was seen in two of seven (29%) at 72 h. These patients received definitive therapy for NCPH after diagnosis. Mortality and costs were substantially higher in the non-cyanoacrylate group. The odds of death were greater by 7-fold in the non-cyanoacrylate group than within the cyanoacrylate group (95% CI = 1.18–41.36, p = 0.0318). At 3 months, there was a 3.18-fold difference (95% CI = 1.05–9.64, p = 0.0411) in accrued costs; at 1 yr, the difference was 2.55-fold (95% CI = 0.96–6.94, p = 0.0585). The cost-effective ratio was estimated as