Combined endoscopic mucosal resection and photodynamic therapy for esophageal neoplasia within Barrett's esophagus

Advancements in photodynamic therapy of esophageal cancer

The poor prognosis of patients with esophageal cancer leads to the constant search for new ways of treatment of this disease. One of the methods used in high-grade dysplasia, superficial invasive carcinoma, and sometimes palliative care is photodynamic therapy (PDT). This method has come a long way from the first experimental studies to registration in the treatment of esophageal cancer and is constantly being improved and refined. This review describes esophageal cancer, current treatment methods, the introduction to PDT, the photosensitizers (PSs) used in esophageal carcinoma PDT, PDT in squamous cell carcinoma (SCC) of the esophagus, and PDT in invasive adenocarcinoma of the esophagus. For this review, research and review articles from PubMed and Web of Science databases were used. The keywords used were "photodynamic therapy in esophageal cancer" in the years 2000-2020. The total number of papers returned was 1,000. After the review was divided into topic blocks and the searched publications were analyzed, 117 articles were selected.

The influence of photodynamic therapy on the Warburg effect in esophageal cancer cells

To investigate whether the Warburg effect is a key modulator on the resistance mechanism of photodynamic therapy (PDT). Glycolysis was examined by the test of lactate product and glucose uptake at different post-PDT time points. Cell viability was detected by the CCK-8 assay and cell proliferation was detected by colony formation assay. The expression of glycolysis and related proteins were examined by western blotting. Target gene was silenced by RNAi. In the present study, we assessed the effect of PDT on cancer cell glycolysis. Our team has demonstrated that pyruvate kinase M2 (PKM2), a key speed-limiting enzyme of glycolysis, was significantly overexpressed in patients with esophageal cancer. Our results in the present study showed that PKM2 was downregulated, and lactate product and glucose uptake were inhibited in cells exposed to 5-aminolevulinic acid (5-ALA)-mediated PDT at 4 h after treatment. However, at 24 h after PDT, we observed a substantial increase in PKM2 expression, lactate product, and glucose uptake. Moreover, silencing of PKM2 gene abrogated the upregulatory effect of PDT on glycolysis at late post-PDT period. 2-Deoxy-D-glucose (2-DG) is a recognized chemical inhibitor of glycolysis. The combined treatment of 2-DG and PDT significantly inhibited tumor growth in vitro at 24 h. These results demonstrate that PDT drives the Warburg effect in a time-dependent manner, and PKM2 plays an important role in this progress, which indicated that PKM2 may be a potential molecular target to increase the sensitivity of esophageal cancer cells to PDT.

Discovery, Validation, and Application of Novel Methylated DNA Markers for Detection of Esophageal Cancer in Plasma

PURPOSE

The burden of esophageal cancer continues to rise, and noninvasive screening tools are needed. Methylated DNA markers (MDM) assayed from plasma show promise in detection of other cancers. For esophageal cancer detection, we aimed to discover and validate MDMs in tissue, and determine their feasibility when assayed from plasma.

EXPERIMENTAL DESIGN

Whole-methylome sequencing was performed on DNA extracted from 37 tissues (28 EC; 9 normal esophagus) and 8 buffy coat samples. Top MDMs were validated by methylation specific PCR on tissue from 76 EC (41 adeno, 35 squamous cell) and 17 normal esophagus. Quantitative allele-specific real-time target and signal amplification was used to assay MDMs in plasma from 183 patients (85 EC, 98 controls). Recursive partitioning (rPART) identified MDM combinations predictive of esophageal cancer. Validation was performed in silico by bootstrapping.

RESULTS

From discovery, 23 candidate MDMs were selected for independent tissue validation; median area under the receiver operating curve (AUC) for individual MDMs was 0.93. Among 12 MDMs advanced to plasma testing, rPART modeling selected a 5 MDM panel (FER1L4, ZNF671, ST8SIA1, TBX15, ARHGEF4) which achieved an AUC of 0.93 (95% CI, 0.89-0.96) on best-fit and 0.81 (95% CI, 0.75-0.88) on cross-validation. At 91% specificity, the panel detected 74% of esophageal cancer overall, and 43%, 64%, 77%, and 92% of stages I, II, III, and IV, respectively. Discrimination was not affected by age, sex, smoking, or body mass index.

CONCLUSIONS

Novel MDMs assayed from plasma detect esophageal cancer with moderate accuracy. Further optimization and clinical testing are warranted.

Endoscopic therapy for Barrett’s esophagus and early esophageal cancer: Where do we go from here?

Since Barrett’s esophagus is a precancerous condition, efforts have been made for its eradication by various ablative techniques. Initially, laser ablation was attempted in non-dysplastic Barrett’s esophagus and subsequently, endoscopic ablation using photodynamic therapy was used in Barrett’s patients with high-grade dysplasia who were poor surgical candidates. Since then, various ablative therapies have been developed with radiofrequency ablation having the best quality of evidence. Resection of dysplastic areas only without complete removal of entire Barrett’s segment is associated with high risk of developing metachronous neoplasia. Hence, the current standard of management for Barrett’s esophagus includes endoscopic mucosal resection of visible abnormalities followed by ablation to eradicate remaining Barrett’s epithelium. Although endoscopic therapy cannot address regional lymph node metastases, such nodal involvement is present in only 1% to 2% of patients with intramucosal adenocarcinoma in Barrett esophagus and therefore is useful in intramucosal cancers. Post ablation surveillance is recommended as recurrence of intestinal metaplasia and dysplasia have been reported. This review includes a discussion of the technique, efficacy and complication rate of currently available ablation techniques such as radiofrequency ablation, cryotherapy, argon plasma coagulation and photodynamic therapy as well as endoscopic mucosal resection. A brief discussion of the emerging technique, endoscopic submucosal dissection is also included.

Oesophageal biopsies are insufficient to predict final histology after endoscopic resection in early Barrett's neoplasia

BACKGROUND

Endoscopic resection (ER) with or without ablation is the first choice treatment for early Barrett's neoplasia. Adequate staging is important to assure a good oncological outcome.

OBJECTIVE

The purpose of this study was to investigate the diagnostic accuracy of pre-operative biopsies in patients who undergo ER for high-grade dysplasia (HGD) or early adenocarcinoma (EAC) in Barrett's oesophagus (BE) and the cardia.

METHODS

Between November 2005-May 2012, 142 ERs performed in 137 patients were obtained. Worst pre-ER and ER histology were compared. Upgrading/downgrading was defined as any more/less severe histological grading on the ER specimen.

RESULTS

The accuracy of pre-ER biopsies in predicting final histology was 61%. ER changed the pre-treatment diagnosis in 55 of the 142 procedures (39%) with downgrading in 23 cases (16%) and upgrading from HGD to T1a or T1b in 32 cases (23%). In the majority of upgraded cases, a visible lesion according to the Paris classification could be detected (26/32, 81%).

CONCLUSION

The diagnostic accuracy of oesophageal biopsies alone in predicting final pathology in Barrett's dysplasia is only 61%. The majority of upgraded lesions are detectable. When ablative therapy is considered in HGD Barrett's dysplasia a meticulous inspection for and removal of all small visible lesions is mandatory.

Endoscopic resection of gastric and esophageal cancer

Endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) techniques have reduced the need for surgery in early esophageal and gastric cancers and thus has lessened morbidity and mortality in these diseases. ESD is a relatively new technique in western countries and requires rigorous training to reproduce the proficiency of Asian countries, such as Korea and Japan, which have very high complete (en bloc) resection rates and low complication rates. EMR plays a valuable role in early esophageal cancers. ESD has shown better en bloc resection rates but it is easier to master and maintain proficiency in EMR; it also requires less procedural time. For early esophageal adenocarcinoma arising from Barrett’s, ESD and EMR techniques are usually combined with other ablative modalities, the most common being radiofrequency ablation because it has the largest dataset to prove its success. The EMR techniques have been used with some success in early gastric cancers but ESD is currently preferred for most of these lesions. ESD has the added advantage of resecting into the submucosa and thus allowing for endoscopic resection of more aggressive (deeper) early gastric cancer.

EMR is not inferior to ESD for early Barrett's and EGJ neoplasia: An extensive review on outcome, recurrence and complication rates

Background and study aims In recent years, it has been reported that early Barrett's and esophagogastric junction (EGJ) neoplasia can be effectively and safely treated using endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). Multiband mucosectomy (MBM) appears to be the safest EMR method. The aim of this systematic review is to assess the safety and efficacy of MBM compared with ESD for the treatment of early neoplasia in Barrett's or at the EGJ. Methods A literature review of studies published up to May 2013 on EMR and ESD for early Barrett's esophagus (BE) neoplasia and adenocarcinoma at the EGJ was performed through MEDLINE, EMBASE and the Cochrane Library. Results on outcome parameters such as number of curative resections, complications and procedure times are compared and reported. Results A total of 16 studies met the inclusion criteria for analysis in this study. There were no significant differences in recurrence rates when comparing EMR (10/380, 2.6 %) to ESD (1/333, 0.7 %) (OR 8.55; 95 %CI, 0.91 - 80.0, P = 0.06). All recurrences after EMR were treated with additional endoscopic resection. The risks of delayed bleeding, perforation and stricture rates in both groups were similar. The procedure was considerably less time-consuming in the EMR group (mean time 36.7 min, 95 %CI, 34.5 - 38.9) than in the ESD group (mean time 83.3 min, 95 %CI, 57.4 - 109.2). Conclusions The MBM technique for EMR is as effective as ESD when comparing outcomes related to recurrence and complication rates for the treatment of early Barrett's or EGJ neoplasia. The MBM technique is considerably less time-consuming.

Endoscopic and surgical resection of T1a/T1b esophageal neoplasms: A systematic review

AIM: To investigate potential therapeutic recommendations for endoscopic and surgical resection of T1a/T1b esophageal neoplasms.

METHODS: A thorough search of electronic databases MEDLINE, Embase, Pubmed and Cochrane Library, from 1997 up to January 2011 was performed. An analysis was carried out, pooling the effects of outcomes of 4241 patients enrolled in 80 retrospective studies. For comparisons across studies, each reporting on only one endoscopic method, we used a random effects meta-regression of the log-odds of the outcome of treatment in each study. “Neural networks” as a data mining technique was employed in order to establish a prediction model of lymph node status in superficial submucosal esophageal carcinoma. Another data mining technique, the “feature selection and root cause analysis”, was used to identify the most important predictors of local recurrence and metachronous cancer development in endoscopically resected patients, and lymph node positivity in squamous carcinoma (SCC) and adenocarcinoma (ADC) separately in surgically resected patients.

RESULTS: Endoscopically resected patients: Low grade dysplasia was observed in 4% of patients, high grade dysplasia in 14.6%, carcinoma in situ in 19%, mucosal cancer in 54%, and submucosal cancer in 16% of patients. There were no significant differences between endoscopic mucosal resection and endoscopic submucosal dissection (ESD) for the following parameters: complications, patients submitted to surgery, positive margins, lymph node positivity, local recurrence and metachronous cancer. With regard to piecemeal resection, ESD performed better since the number of cases was significantly less [coefficient: -7.709438, 95%CI: (-11.03803, -4.380844), P < 0.001]; hence local recurrence rates were significantly lower [coefficient: -4.033528, 95%CI: (-6.151498, -1.915559), P < 0.01]. A higher rate of esophageal stenosis was observed following ESD [coefficient: 7.322266, 95%CI: (3.810146, 10.83439), P < 0.001]. A significantly greater number of SCC patients were submitted to surgery (log-odds, ADC: -2.1206 ± 0.6249 vs SCC: 4.1356 ± 0.4038, P < 0.05). The odds for re-classification of tumor stage after endoscopic resection were 53% and 39% for ADC and SCC, respectively. Local tumor recurrence was best predicted by grade 3 differentiation and piecemeal resection, metachronous cancer development by the carcinoma in situ component, and lymph node positivity by lymphovascular invasion. With regard to surgically resected patients: Significant differences in patients with positive lymph nodes were observed between ADC and SCC [coefficient: 1.889569, 95%CI: (0.3945146, 3.384624), P < 0.01). In contrast, lymphovascular and microvascular invasion and grade 3 patients between histologic types were comparable, the respective rank order of the predictors of lymph node positivity was: Grade 3, lymphovascular invasion (L+), microvascular invasion (V+), submucosal (Sm) 3 invasion, Sm2 invasion and Sm1 invasion. Histologic type (ADC/SCC) was not included in the model. The best predictors for SCC lymph node positivity were Sm3 invasion and (V+). For ADC, the most important predictor was (L+).

CONCLUSION: Local tumor recurrence is predicted by grade 3, metachronous cancer by the carcinoma in-situ component, and lymph node positivity by L+. T1b cancer should be treated with surgical resection.

Argon plasma coagulation for superficial esophageal squamous-cell carcinoma in high-risk patients

AIM: To evaluate the usefulness and safety of argon plasma coagulation (APC) for superficial esophageal squamous-cell carcinoma (SESC) in high-risk patients.

METHODS: We studied 17 patients (15 men and 2 women, 21 lesions) with SESC in whom endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), and open surgery were contraindicated from March 1999 through February 2009. None of the patients could tolerate prolonged EMR/ESD or open surgery because of severe concomitant disease (e.g., liver cirrhosis, cerebral infarction, or ischemic heart disease) or scar formation after EMR/ESD and chemoradiotherapy. After conventional endoscopy, an iodine stain was sprayed on the esophageal mucosa to determine the lesion margins. The lesion was then ablated by APC. We retrospectively studied the treatment time, number of APC sessions per site, complications, presence or absence of recurrence, and time to recurrence.

RESULTS: The median duration of follow-up was 36 mo (range: 6-120 mo). All of the tumors were macroscopically classified as superficial and slightly depressed type (0-IIc). The preoperative depth of invasion was clinical T1a (mucosal cancer) for 19 lesions and clinical T1b (submucosal cancer) for 2. The median treatment time was 15 min (range: 10-36 min). The median number of treatment sessions per site was 2 (range: 1-4). The median hospital stay was 14 d (range: 5-68 d). Among the 17 patients (21 lesions), 2 (9.5%) had recurrence and underwent additional APC with no subsequent evidence of recurrence. There were no treatment-related complications, such as bleeding or perforation.

CONCLUSION: APC is considered to be safe and effective for the management of SESC that cannot be resected endoscopically because of underlying disease, as well as for the control of recurrence after EMR and local recurrence after chemoradiotherapy.

Barrett's esophagus with high-grade dysplasia: Focus on current treatment options

High-grade dysplasia (HGD) in Barrett’s esophagus (BE) is the critical step before invasive esophageal adenocarcinoma. Although its natural history remains unclear, an aggressive therapeutic approach is usually indicated. Esophagectomy represents the only treatment able to reliably eradicate the neoplastic epithelium. In healthy patients with reasonable life expectancy, vagal-sparing esophagectomy, with associated low mortality and low early and late postoperative morbidity, is considered the treatment of choice for BE with HGD. Patients unfit for surgery should be managed in a less aggressive manner, using endoscopic ablation or endoscopic mucosal resection of the entire BE segment, followed by lifelong surveillance. Patients eligible for surgery who present with a long BE segment, multifocal dysplastic lesions, severe reflux symptoms, a large fixed hiatal hernia or dysphagia comprise a challenging group with regard to the appropriate treatment, either surgical or endoscopic.

Length of Barrett's segment predicts success of extensive endomucosal resection for eradication of Barrett's esophagus with early neoplasia

BACKGROUND

Although the efficacy and safety of extensive endomucosal resection (EMR) in eradicating Barrett's esophagus (BE) harbouring early neoplasia have been established, factors predicting efficacy remains unclear.

AIM

To determine the complete eradication rate of Barrett's esophagus with high-grade intraepithelial neoplasia (HGIN) or intramucosal carcinoma (IMC), safety, and factors predicting complete eradication by EMR.

METHODS

Patients with histological confirmation of Barrett's HGIN/IMC were prospectively identified. EMR was performed using Duette multiband ligator or cap technique by a single operator (NEM).

RESULTS

99 patients (81 males) with median age 67 years [interquartile range (IQR) 60-77 years] and median Barrett's length 4 cm (IQR 2-6 cm) were included. Of 628 index EMRs [mean 6.3, median 5 (IQR 3-8)], 23% showed IMC, 58.5% showed HGIN, and 16% showed low-grade dysplasia only. A median of 8 EMR resections per patient (IQR 6-16, 1,064 resections in 89 patients) resulted in complete eradication of BE harboring neoplasia in 49.4% and eradication of HGIN/IMC in 81% (BE <5 cm subgroup: 65% complete eradication and 91% HGIN eradication) at median follow-up of 18 months (range 6-27 months). On univariate analysis, focal dysplasia (P = 0.003) and Barrett's length <5 cm (P = 0.001) were predictors of complete BE eradication. Barrett's length <5 cm was the only significant predictor [odds ratio (OR) 3.4, standard error (SE) 0.11, P = 0.0006] on multiple logistic regression analysis. Strictures developed in 27% and major bleeding in 2% with no procedure-related perforations or mortality.

CONCLUSIONS

Extensive EMR for removal of BE with early neoplasia is safe. Outcomes for complete BE eradication are modest at 49.4% and eradication of high-grade dysplasia at 81%. Barrett's length <5 cm is the only significant predictor of complete response.

Endoscopic Resection with Ligation Using a Multi-Band Mucosectomy System in Barrett's Esophagus with High-Grade Dysplasia and Intramucosal Carcinoma

BACKGROUND

Endoscopic therapy for early neoplasia in Barrett's esophagus (BE) is evolving. Endoscopic resection has an increasing role. We wanted to evaluate the safety and efficacy of multi-band ligation/resection [ER-L] without pre-injection in BE with high-grade dysplasia [HGD] and intramucosal carcinoma [IMCA].

METHODS

A cohort of 65 consecutive patients from a single academic medical center, who underwent ER-L as part of endoscopic eradication therapy for BE with HGD/IMCA were studied. ER-L was performed afterendoscopic mapping and endoscopic ultrasound (EUS). Subsequently, adjunctive ablative therapies including photodynamic therapy, argon plasma coagulation and radiofrequency ablation were applied to achieve complete eradication of all BE. Thereafter biopsy surveillance was performed per protocol. All patients were prescribed a proton-pump inhibitor.

MAIN OUTCOME MEASUREMENTS

Change in histopathological stage; eradication of BE and HGD/IMCA; adverse events.

RESULTS

The median number of ER-L applications in each session was 4 (range 1-6) and the mean total number of ER-L sessions was 1.5. Compared with prior forceps biopsy, histopathology from the ER-L specimen changed in 24 (37.5%, p = <0.0001). With median follow-up of 15 months (range 8-42), complete and durable BE eradication was achieved with ER-L alone in 36 (60%) and the remainder with adjunctive ablation therapies. There were nine complications (four (6%) acute bleeding, five (7.5%) strictures, zero perforations).

CONCLUSIONS

ER-L without submucosal (SM) pre-injection is safe and effective when applied selectively for eradication of BE with HGD/IMCA. There is significant change in pathological stage after ER-L conferring a diagnostic and staging advantage. ER-L may be used adjunctively with ablation therapies.

Barrett's adenocarcinoma of the esophagus: better outcomes through new methods of diagnosis and treatment

BACKGROUND

Esophageal adenocarcinoma has attracted more attention among gastroenterologists recently because of its rapidly rising incidence in Western countries. Many new epidemiological findings have been published, and there have been numerous technical advances in diagnostic procedures and in multimodal treatment based on the staging of the disease.

METHODS

In this paper, we selectively review the literature on esophageal adenocarcinoma, also considering the evidence-based recommendations contained in the guidelines of the German Society for Digestive and Metabolic Diseases (Deutsche Gesellschaft für Verdauungs- und Stoffwechselkrankheiten, DGVS) as well as the latest data from our own research team.

RESULTS AND CONCLUSION

here have been major recent advances in the diagnosis and treatment of esophageal adenocarcinoma. New refinements in endoscopic techniques now make endoscopic treatment possible for early esophageal carcinoma. New surgical techniques and new strategies of neoadjuvant chemotherapy have lowered the morbidity and improved the outcome of patients with locally advanced disease. Molecular therapies, too, have shown promising initial results.

Endoscopic treatment of Barrett’s esophagus: From metaplasia to intramucosal carcinoma

The annual incidence of adenocarcinoma arising from Barrett’s esophagus (BE) is approximately 0.5%. Through a process of gradual transformation from low-grade dysplasia to high-grade dysplasia (HGD), adenocarcinoma can develop in the setting of BE. The clinical importance of appropriate identification and treatment of BE in its various stages, from intestinal metaplasia to intramucosal carcinoma (IMC) hinges on the dramatically different prognostic status between early neoplasia and more advanced stages. Once a patient has symptoms of adenocarcinoma, there is usually locally advanced disease with an approximate 5-year survival rate of about 20%. Esophagectomy has been the gold standard treatment for BE with HGD, due to the suspected risk of harboring occult invasive carcinoma, which was traditionally estimated to be as high as 40%. In recent years, the paradigm of BE early neoplasia management has recently evolved, and endoscopic therapies (endoscopic mucosal resection, radiofrequency ablation, and cryotherapy) have entered the clinical forefront as acceptable non-surgical alternatives for HGD and IMC. The goal of endoscopic therapy for HGD or IMC is to ablate all BE epithelium (both dysplastic and non-dysplastic) due to risk of synchronous/metachronous lesion development in the remaining BE segment.

Early events during neoplastic progression in Barrett's esophagus

Barrett's esophagus is a condition in which the stratified squamous epithelium of the distal esophagus is replaced by specialized intestinal metaplasia. Clinical management of Barrett's esophagus, like many other "premalignant" conditions, is characterized by overdiagnosis of benign early changes that will not cause death or suffering during the lifetime of an individual and underdiagnosis of life-threatening early disease. Recent studies of a number of different types of cancer have revealed much greater genomic complexity than was previously suspected. This genomic complexity could create challenges for early detection and prevention if it develops in premalignant epithelia prior to cancer. Neoplastic progression unfolds in space and time, and Barrett's esophagus provides one of the best models for rapid advances, including "gold standard" cohort studies, to distinguish individuals who do and do not progress to cancer. Specialized intestinal metaplasia has many properties that appear to be protective adaptations to the abnormal environment of gastroesophageal reflux. A large body of evidence accumulated over several decades implicates chromosome instability in neoplastic progression from Barrett's esophagus to esophageal adenocarcinoma. Small, spatial scale studies have been used to infer the temporal order in which genomic abnormalities develop during neoplastic progression in Barrett's esophagus. These spatial studies have provided the basis for prospective cohort studies of biomarkers, including DNA content abnormalities (tetraploidy, aneuploidy) and a biomarker panel of 9p LOH, 17p LOH and DNA content abnormalities. Recent advances in SNP array technology provide a uniform platform to assess chromosome instability.

[Diagnostic and interventional endoscopy in gastroenterology : from high-resolution chips and procedures for endoscopic resection to NOTES]

In the past 10 years endoscopic diagnostics has benefited from technologies such as big chips, high-definition television (HDTV) and narrow band imaging (NBI). Video capsule endoscopy and double balloon enteroscopy have facilitated visualization of the entire small bowel. A number of studies on mucosal Barrett's and gastric cancers could prove that endoscopic mucosal resection (EMR) is oncologically equivalent to surgical resection when certain criteria are respected. However, EMR is less invasive and carries a substantially lower complication risk and mortality compared to surgery. Endoscopic submucosal dissection (ESD) facilitates en bloc resection with thorough histopathologic evaluation of the specimen, e.g. for mucosal lesions in the stomach and rectum. Endosonography (EUS) guided transgastric necrosectomy using a flexible gastroscope has set a milestone in the treatment of infected pancreatic necroses and has replaced open surgery in many centers. Natural orifice transluminal endoscopic surgery (NOTES) uses natural body openings as minimally invasive access to the abdomen and mediastinum. Interventional GI endoscopists and minimally invasive surgeons have profited from these innovations in micromechanics and microelectronics.

Surveillance in Barrett's esophagus: a failed premise

BACKGROUND

It is recommended that patients in whom Barrett's esophagus is diagnosed undergo surveillance endoscopy. However, multiple issues regarding the efficacy and feasibility of surveillance remain.

METHODS

Quantitative techniques were used to examine surveillance in patients with Barrett's esophagus. A retrospective case-control study was performed to determine whether surveillance endoscopy prolonged survival in a cohort of U.S. veterans diagnosed with esophageal adenocarcinoma. Cost-effectiveness analysis was employed to compare competing strategies of management for patients with Barrett's esophagus to determine whether surveillance strategies using alternative biomarkers could out-perform dysplasia based surveillance, and whether new techniques for eradicating Barrett's metaplasia would constitute cost-effective strategies.

RESULTS

Surveillance did not improve long-term survival among veterans diagnosed with esophageal adenocarcinoma. Lead-time bias has confounded previous reports claiming the efficacy of endoscopic surveillance. Cost-effectiveness analysis revealed that while screening 50-year old Caucasian males with heartburn may be cost-effective, surveillance even at 5 year intervals among patients with Barrett's esophagus without dysplasia exceeded the threshold of cost-effective care. If a biomarker were developed whose sensitivity and specificity to predict cancer development exceeded 80%, this could represent a more viable strategy than dysplasia-based surveillance and overcome the inherent inter- and intra-observer variations in dysplasia diagnosis that currently limit the effectiveness of surveillance programs. Finally, techniques that reduce cancer incidence such as endoscopic mucosal resection or ablation will likely be more cost-effective than current surveillance strategies that rely on early detection of cancer.

CONCLUSIONS

Current recommendations for the management of patients with Barrett's esophagus are flawed. Future guidelines should include alternative markers of cancer risk and focus on strategies that reduce cancer incidence instead of cancer detection.

Endoscopic resection of superficial gastrointestinal tumors

Therapeutic endoscopy plays a major role in the management of gastrointestinal (GI) neoplasia. Its indications can be generalized into four broad categories; to remove or obliterate neoplastic lesion, to palliate malignant obstruction, or to treat bleeding. Only endoscopic resection allows complete histological staging of the cancer, which is critical as it allows stratification and refinement for further treatment. Although other endoscopic techniques, such as ablation therapy, may also cure early GI cancer, they can not provide a definitive pathological specimen. Early stage lesions reveal low frequency of lymph node metastasis which allows for less invasive treatments and thereby improving the quality of life when compared to surgery. Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are now accepted worldwide as treatment modalities for early cancers of the GI tract.

How effective is endoscopic therapy in the treatment of patients with early esophageal cancer?

Endoscopic therapy is increasingly used to treat high-grade dysplasia and/or early mucosal adenocarcinoma in patients with Barrett's esophagus. However, no randomized controlled trials have directly compared the efficacy of endoscopic therapy and traditional surgical approaches. This commentary discusses the findings of a retrospective, population-based study by Das et al. that demonstrates the effectiveness of endoscopic resection and/or endoscopic ablation in the treatment of early esophageal cancer. This study used data from the Surveillance Epidemiology and End Results database of the National Cancer Institute to compare cancer-free survival in patients with early esophageal cancer who were either treated with endoscopic therapy (n = 99) or surgical resection (n = 643). Analysis using a Cox proportional hazards model did not reveal a difference in esophageal cancer-specific mortality between the two groups. These results, therefore, support the use of endoscopic therapy in the treatment of early-stage esophageal cancer.

Correlation of histology with biomarker status after photodynamic therapy in Barrett esophagus

BACKGROUND

Currently, histology is used as the endpoint to define success with photodynamic therapy (PDT) in patients with high-grade dysplasia (HGD). Recurrences despite 'successful' ablation are common. The role of biomarkers in assessing response to PDT remains undefined. The objectives of the current study were 1) to assess biomarkers in a prospective cohort of patients with HGD/mucosal cancer before and after PDT and 2) to correlate biomarker status after PDT with histology.

METHODS

Patients who underwent PDT for HGD/mucosal cancer were studied prospectively. All patients underwent esophagogastroduodenoscopy, 4-quadrant biopsies every centimeter, endoscopic mucosal resection of visible nodules, and endoscopic ultrasound. Cytology samples were obtained by using standard cytology brushes. Biomarkers were assessed by using fluorescence in situ hybridization (FISH). The biomarkers that were assessed included loss of 9p21 (site of the p16 gene) and 17p13.1 (site of the p53 gene) loci; gains of the 8q24(c-myc), 17q (HER2-neu), and 20q13 loci; and multiple gains. Patients received PDT 48 hours after the administration of sodium porfimer. Demographic and clinical variables were collected prospectively. Patients were followed with endoscopy and repeat cytology for biomarkers. The McNemar test was used to compare biomarker proportions before and after PDT.

RESULTS

Thirty-one patients were studied. The median patient age was 66 years (interquartile range [IQR], 56-73 years), and 28 patients (88%) were men. The mean Barrett segment length was 5 cm (standard error of the mean, 0.5 cm). Post-PDT biomarkers were obtained after a median duration of 9 months (IQR, 3-12 months). There was a statistically significant decrease in the proportion of several biomarkers assessed after PDT. Six patients without HGD after PDT still had positive FISH results for 1 or more biomarkers: of these, 2 patients (33%) developed recurrent HGD.

CONCLUSIONS

In this initial study, histologic downgrading of dysplasia after PDT was associated with the loss of biomarkers that have been associated with progression of neoplasia in Barrett esophagus. Patients with persistently positive biomarkers appeared to be at a higher risk of recurrent HGD. These findings should be confirmed in a larger study.

Barrett's esophagus and the increasing role of endoluminal therapy

Barrett's esophagus, or the presence of specialized intestinal mucosa in the esophagus that has a malignant potential, has experienced a rapid increase in diagnosis and prevalence over the past few decades. Once thought to progress to adenocarcinoma in an orderly sequence of increasing dysplasia, recent data suggest the process can be more random. In combination with targeted surveillance endoscopy, recent improvements in technology have aided endoluminal therapy in becoming a cost-effective adjunct to medication. When used in combination, in particular, these ablative therapies have become suitable, if not preferable, alternatives to surgery in many patients.

Perspective on the practical indications of endoscopic submucosal dissection of gastrointestinal neoplasms

Endoscopic submucosal dissection (ESD) is a new endoluminal therapeutic technique involving the use of cutting devices to permit a larger resection of the tissue over the muscularis propria. The major advantages of the technique in comparison with polypectomy and endoscopic mucosal resection are controllable resection size and shape and en bloc resection of a large lesion or a lesion with ulcerative findings. This technique is applied for the endoscopic treatment of epithelial neoplasms in the gastrointestinal tract from the pharynx to the rectum. Furthermore, some carcinoids and submucosal tumors in the gastrointestinal tract are treated by ESD. To determine the indication, two aspects should be considered. The first is a little likelihood of lymph node metastasis and the second is the technical resectability. In this review, practical guidelines of ESD for the gastrointestinal neoplasms are discussed based on the evidence found in the literature.

[Endosonography of the gastrointestinal tract]

The clinical value of endosonography (EUS) in the gastrointestinal (GI) tract is currently increasing and supported by new imaging techniques. Conventional EUS combined with contrast application or elastography might further refine the diagnostic yield for GI cancers. The present review discusses current standards of EUS and endosonographically guided therapy and discusses newly available imaging modalities.

Significance of neoplastic involvement of margins obtained by endoscopic mucosal resection in Barrett's esophagus

OBJECTIVES

Although EMR has been used for elimination of neoplasia in BE, the significance of positive carcinoma margins and depth of invasion on endoscopic resection pathology has not been assessed using a valid standard. The aim of this study was to assess the accuracy of tumor staging by EMR using esophagectomy as the standard.

METHODS

Medical records of patients, who underwent endoscopic resection for esophageal carcinoma or high-grade dysplasia in BE followed by esophagectomy, were reviewed. Data were abstracted from a prospectively maintained EMR database. Endosonography and endoscopic resection were performed by a single experienced endoscopist. Two experienced GI pathologists interpreted all histological results. Standard statistical tests were used to compare continuous and categorical variables.

RESULTS

Twenty-five patients were included in the study. Three patients had mucosal carcinoma and 16 had submucosal carcinoma following endoscopic resection. Surgical pathology staging was consistent with preoperative EMR staging in all patients. No patient with negative mucosal resection margins had residual tumor at the resection site at esophagectomy. In patients with submucosal carcinoma, 8 had residual carcinoma at the EMR site at surgery and 5 patients had metastatic lymphadenopathy.

CONCLUSIONS

Tumor staging using EMR pathology is accurate when compared with surgical pathology following esophagectomy. Negative margins on EMR pathology correlate with absence of residual disease at the EMR site at esophagectomy. Submucosal carcinoma on EMR specimens was associated with a high prevalence of residual disease at surgery (50%) and metastatic lymphadenopathy (31%).

Endoscopic mucosal resection and endoscopic submucosal dissection as treatments for early gastrointestinal cancers in Western countries

Early gastrointestinal cancers are defined as lesions limited to the mucosa or submucosa without invading the muscularis propria, regardless of the presence of lymph node metastases. Although the natural history of these diseases is basically alike worldwide, its management is quite different between the East and West; aggressive surgery is frequently adopted by Western surgeons, while less invasive techniques are adopted by Asian colleagues. These techniques include endoscopic mucosal resection and endoscopic submucosal dissection which are now accepted as treatments for early gastrointestinal cancers in selected cases. Recent advances in endoscopic detection and treatment techniques, especially in Japan and Korea, have prompted Western endoscopists to learn these techniques. This review addresses recent advances regarding endoscopic resections of early gastrointestinal cancers, which promoted its use in Western countries. In addition, prospective studies on endoscopic resection in Western countries are also described.

Circumferential endoscopic resection of Barrett's esophagus with high-grade dysplasia or early adenocarcinoma

BACKGROUND

Barrett's esophagus-related high-grade dysplasia or mucosal cancer can be treated by endoscopic mucosal resection (EMR), but the adjacent metaplastic epithelium remains at risk for developing further lesions. Our objective was to evaluate the results of the circumferential EMR in removing not only the neoplastic lesion but also the remaining Barrett's epithelium.

METHODS

Forty-one consecutive patients (mean age: 66 years) with Barrett's esophagus were submitted to 63 EMR sessions in one single-referral endoscopic unit. All patients had high-grade dysplasia, and cancer was detected in 23 of these cases, most of them classified as T1N0 (20 patients) by endosonography. Mucosectomy after saline submucosal injection was performed for the neoplastic lesions and, if necessary, the residual Barrett's epithelium was removed by the same technique one month later.

RESULTS

A retrospective evaluation showed that, during a mean follow-up of 31.6 months, Barrett's epithelium was completely replaced by squamous epithelium in 31 (75.6%) cases. There were 10 complications, all of which were managed endoscopically: 8 cases of bleeding and two perforations occurred in 9 (14.3%) patients. One patient developed an esophageal stricture. Barrett's epithelium recurred in 10 (24.4%) patients and recurrent or metachronous early cancer was detected in 5 (12.2%), all but one of which were treated again by EMR; the fifth patient was referred to surgery. Argon plasma coagulation was used in 6 cases to treat Barrett's epithelium, and two patients received concomitant chemoradiotherapy as adjuvant therapy.

CONCLUSIONS

Circumferential EMR provides an effective endoscopic approach to the management of Barrett's esophagus-related high-grade dysplasia and mucosal cancer. Additional studies are necessary to evaluate the long-term results.

[Mucosectomy as sufficient therapy for early squamous cell]

Squamous cell carcinoma of the esophagus can be treated endoscopically under certain conditions. A carcinoma (T1a) limited to the mucosa with a low infiltration depth (m1-m2) and limited extent (< or =2 cm) can be removed by electrical snare with no risk of lymph node metastasis. Due to the increased risk of lymphatic spread, deeply infiltrating submucosal tumours (sm2-sm3) must be treated by surgical resection. Endoscopic resection (mucosectomy) is performed by electric snare and the cap method, additionally with APC coagulation or photodynamic therapy. Multifocal tumour growth and incomplete resection are both risk factors for local recurrence. If the strict conditions for endoscopic resection are fulfilled, the 5-year survival time of these patients with early cancer is no different from that of the population as a whole.

Frozen section analysis of esophageal endoscopic mucosal resection specimens in the real-time management of Barrett's esophagus

BACKGROUND & AIMS

The aim of this study was to assess the validity of frozen section analysis of endoscopic mucosal resection (EMR) specimens from Barrett's esophagus as compared with permanent sections for the detection of neoplasia. Frozen sections help to give immediate feedback for surgical procedures. It has not been determined whether EMR can be adequately interpreted by using frozen sections to aid endoscopists in completely resecting neoplastic lesions.

METHODS

EMR specimens from Barrett's esophagus with high-grade dysplasia (HGD) and/or carcinoma were tested by frozen section. Pathologists evaluated EMR specimens for the depth of invasion as well as the appearance of clear margins of resection. The kappa statistic was calculated to assess the degree of agreement between the frozen section and permanent section diagnoses.

RESULTS

Twenty-three consecutive patients underwent 30 EMRs with frozen section diagnosis. Frozen section revealed a carcinoma in 7 specimens (23%) and dysplasia in 20 (66%). Permanent sections found carcinoma in 8 specimens (26%), dysplasia in 19 specimens (63%), and normal or nondysplastic Barrett's esophagus in the remainder. The kappa statistic for the depth of invasion of EMR specimens was 0.93 (near perfect agreement). The kappa statistic for the margins of the EMR specimens was 0.80 (excellent agreement).

CONCLUSIONS

This study indicated that frozen section analysis of esophageal EMR specimens is valid as compared with permanent section. This technique might allow rapid evaluation about the degree and depth of involvement of cancers. This allows physicians to make decisions regarding further therapy if margins are involved or decrease the use of EMR for histologically benign-appearing lesions.

Endoscopic mucosal resection for high-grade dysplasia and intramucosal carcinoma in Barrett’s esophagus: An Italian experience

AIM: To evaluate endoscopic mucosal resection (EMR) in patients with high-grade dysplasia (HGD) and/or intramucosal cancer (IMC) in Barrett’s esophagus (BE).

METHODS: Between June 2000 and December 2003, 39 consecutive patients with HGD (35) and/or IMC (4) underwent EMR. BE >30 mm was present in 27 patients. In three patients with short segment BE (25.0%), HGD was detected in a normal appearing BE. Lesions had a mean diameter of 14.8±10.3 mm. Mucosal resection was carried out using the cap method.

RESULTS: The average size of resections was 19.7±9.4×14.6±8.2 mm. Histopathologic assessment post-resection revealed 5 low-grade dysplasia (LGD) (12.8%), 27 HGD (69.2%), 2 IMC (5.1%), and 5 SMC (-12.8%). EMR changed the pre-treatment diagnosis in 10 patients (25.6%). Three patients with SMC underwent surgery. Histology of the surgical specimen revealed 1 T0N0 and 2 T1N0 lesions. The remaining two patients were cancer free at 32.5 and 45.6 mo, respectively. A metachronous lesion was detected after 25 mo in one patient with HGD. Intra-procedural bleeding, controlled at endoscopy, occurred in four patients (10.3%). After a median follow-up of 34.9 mo, all patients remained in remission.

CONCLUSION: In the medium term, EMR is effective and safe to treat HGD and/or IMC within BE and is a valuable staging method. It could become an alternative to surgery.

Early esophageal cancer: pattern of lymphatic spread and prognostic factors for long-term survival after surgical resection

OBJECTIVE

The objective of this study was to assess the prevalence and pattern of lymphatic spread in patients with early squamous cell and adenocarcinoma and identify prognostic factors for long-term survival after resection and lymphadenectomy.

SUMMARY BACKGROUND DATA

Limited endoscopic approaches without lymphadenectomy are increasingly applied in patients with early esophageal cancer.

MATERIAL AND METHODS

A total of 290 patients with early esophageal cancer (157 adenocarcinoma, 133 squamous cell cancer) had surgical resection with systematic lymphadenectomy. Specimens were assessed for prevalence and pattern of lymphatic spread. Prognostic factors were determined by multivariate analysis.

RESULTS

None of the 70 patients with adenocarcinoma limited to themucosa had lymphatic spread, as compared with 2 of 26 with mucosal squamous cell cancer. Lymphatic spread was more common in patients with submucosal squamous cell cancer as compared with submucosal adenocarcinoma (36.4% versus 20.7%). Although lymph node metastases were usually limited to locoregional lymph node stations in early adenocarcinoma, distant lymphatic spread was frequent in early squamous cell cancer. On multivariate analysis, only histologic tumor type and the presence of lymph node metastases were independent predictors of long-term survival. Five-year survival rate was 83.4% for early adenocarcinoma versus 62.9% for early squamous cell cancer and 48.2% versus 79.5% for patients with/without lymphatic spread.

DISCUSSION

Prevalence and pattern of lymphatic spread as well as long-term prognosis differ markedly between early esophageal squamous cell and adenocarcinoma. Limited resection techniques and individualized lymphadenectomy strategies appear applicable in patients with early adenocarcinoma.

Early esophageal cancer: pattern of lymphatic spread and prognostic factors for long-term survival after surgical resection

OBJECTIVE

The objective of this study was to assess the prevalence and pattern of lymphatic spread in patients with early squamous cell and adenocarcinoma and identify prognostic factors for long-term survival after resection and lymphadenectomy.

SUMMARY BACKGROUND DATA

Limited endoscopic approaches without lymphadenectomy are increasingly applied in patients with early esophageal cancer.

MATERIAL AND METHODS

A total of 290 patients with early esophageal cancer (157 adenocarcinoma, 133 squamous cell cancer) had surgical resection with systematic lymphadenectomy. Specimens were assessed for prevalence and pattern of lymphatic spread. Prognostic factors were determined by multivariate analysis.

RESULTS

None of the 70 patients with adenocarcinoma limited to themucosa had lymphatic spread, as compared with 2 of 26 with mucosal squamous cell cancer. Lymphatic spread was more common in patients with submucosal squamous cell cancer as compared with submucosal adenocarcinoma (36.4% versus 20.7%). Although lymph node metastases were usually limited to locoregional lymph node stations in early adenocarcinoma, distant lymphatic spread was frequent in early squamous cell cancer. On multivariate analysis, only histologic tumor type and the presence of lymph node metastases were independent predictors of long-term survival. Five-year survival rate was 83.4% for early adenocarcinoma versus 62.9% for early squamous cell cancer and 48.2% versus 79.5% for patients with/without lymphatic spread.

DISCUSSION

Prevalence and pattern of lymphatic spread as well as long-term prognosis differ markedly between early esophageal squamous cell and adenocarcinoma. Limited resection techniques and individualized lymphadenectomy strategies appear applicable in patients with early adenocarcinoma.

Endoscopic Mucosal Resection: Esophageal Applications

Endoscopic mucosal resection is an invaluable tool to diagnose and potentially treat superficial cancers in Barrett's esophagus as well as squamous cell cancers. The technique can be performed using equipment available in most endoscopic laboratories. The tissue retrieved from these procedures gives the endoscopist histologic information regarding tumor depth of penetration, which is critical to treatment of early cancers. In addition, standard pinch biopsies are often unable to diagnose malignancies that may underlie areas of dysplasia or even normal mucosa. Endoscopic mucosal resection can be used to diagnose these lesions with relative safety, particularly when applied to the esophagus.

Approach to early Barrett's cancer

Because of effective surveillance programs in patients with known Barrett's esophagus, adenocarcinoma of the distal esophagus is increasingly diagnosed at early stages. With the introduction of limited surgical and endoscopic treatment modalities, the need for radical esophagectomy and extensive lymphadenectomy in such patients has been questioned. When selecting the approach to early Barrett's cancer, the precancerous nature of the underlying Barrett's esophagus, the frequent multicentricity of neoplastic alterations within the Barrett mucosa, the inaccuracy of current staging modalities, and the presence of lymph node metastases should be taken into account. Invasiveness and morbidity of the procedures, as well as quality of life aspects, should also be considered. From an oncologic point of view the minimum extent of a resection for early Barrett's cancer should include a full-thickness removal of the entire segment of the distal esophagus covered by intestinal metaplasia together with a regional lymphadenectomy. In appropriately selected patients this can be achieved by a limited surgical procedure involving transhiatal resection of the distal esophagus, but not by endoscopic mucosal ablation or endoscopic mucosa resection. Our experience with 49 limited surgical resections with regional lymphadenectomy indicates that this procedure is oncologically adequate and safe. Reconstruction with an interposed jejunal loop prevents postoperative gastroesophageal reflux and is associated with good quality of life. In contrast, endoscopic interventions are plagued by a high tumor recurrence rate, probably from persistence of Barrett's mucosa and gastroesophageal reflux.

Barrett's esophagus and Barrett's carcinoma

The alarming rise in the incidence of esophageal adenocarcinomas in the Western world has focused interest on so-called Barrett's esophagus. Barrett's esophagus is characterized by specialized intestinal epithelium replacing the normal squamous epithelium in the distal esophagus and is considered a consequence of long-lasting and severe gastroesophageal reflux disease. A metaplasia-dysplasia-carcinoma sequence links Barrett's esophagus with adenocarcinoma of the distal esophagus (Barrett's cancer). Despite intensive research, many questions concerning the pathogenesis, diagnosis, and treatment of Barrett's esophagus and associated adenocarcinoma are still unanswered. Based on current data, the malignant progression of Barrett's esophagus cannot be substantially prevented by medical or surgical therapy for reflux. Although no firm data are available to show that surveillance strategies can reduce overall mortality from Barrett's cancer, early detection and cure are possible. Management of Barrett's esophagus and carcinoma is reviewed with reference to the sequence of disease from metaplasia to carcinoma.