Occult dysplasia is disclosed by Lugol chromoendoscopy in alcoholics at high risk for squamous cell carcinoma of the esophagus

A case of reflux laryngitis after iodine staining for esophageal squamous cell carcinoma

Iodine staining allows for clear visualization of the lesion boundaries of esophageal squamous cell carcinoma and is used as the gold standard for detecting and diagnosing the extent of the cancer. Heartburn and retrosternal pain are known side effects; however, no reports of pharyngitis or laryngitis exist. Therefore, we present a case of laryngitis caused by iodine reflux. An 80-year-old female patient underwent endoscopic submucosal dissection for superficial esophageal cancer. During the operation, a reflux of the iodine used for diagnosing the extent of the lesion occurred, and she experienced laryngitis accompanied by hoarseness postoperatively, which improved with steroid administration. Laryngitis due to iodine reflux may cause airway stenosis, and preventing reflux requires anterograde application of iodine and spraying iodine as gently and locally as possible.

Squamous Neoplastic Precursor Lesions of the Esophagus

Clinicopathological and molecular studies have demonstrated that dysplasia is a precancerous and/or neoplastic lesion with malignant potential. Further, it is subclassified into two grades: high-grade and low-grade dysplasia. High-grade dysplasia is a clinically significant lesion requiring resection or ablation. Low-grade dysplasia has a much lower risk of carcinoma; thus, it should be followed by endoscopic surveillance. Because squamous dysplasia may progress to squamous cell carcinoma, periodic endoscopy is useful to detect the lesion in patients with risk factors. Squamous dysplasia is diagnosed histopathologically by evaluating both cytologic and structural changes.

Latest Advances in Endoscopic Detection of Oesophageal and Gastric Neoplasia

Endoscopy is the gold standard for the diagnosis of cancers and cancer precursors in the oesophagus and stomach. Early detection of upper GI cancers requires high-quality endoscopy and awareness of the subtle features these lesions carry. Endoscopists performing surveillance of high-risk patients including those with Barrett's oesophagus, previous squamous neoplasia or chronic atrophic gastritis should be familiar with endoscopic features, classification systems and sampling techniques to maximise the detection of early cancer. In this article, we review the current approach to diagnosis of these conditions and the latest advanced imaging and diagnostic techniques.

Application of convolutional neural network-based endoscopic imaging in esophageal cancer or high-grade dysplasia: A systematic review and meta-analysis

BACKGROUND

Esophageal cancer is the seventh-most common cancer type worldwide, accounting for 5% of death from malignancy. Development of novel diagnostic techniques has facilitated screening, early detection, and improved prognosis. Convolutional neural network (CNN)-based image analysis promises great potential for diagnosing and determining the prognosis of esophageal cancer, enabling even early detection of dysplasia.

AIM

To conduct a meta-analysis of the diagnostic accuracy of CNN models for the diagnosis of esophageal cancer and high-grade dysplasia (HGD).

METHODS

PubMed, EMBASE, Web of Science and Cochrane Library databases were searched for articles published up to November 30, 2022. We evaluated the diagnostic accuracy of using the CNN model with still image-based analysis and with video-based analysis for esophageal cancer or HGD, as well as for the invasion depth of esophageal cancer. The pooled sensitivity, pooled specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and area under the curve (AUC) were estimated, together with the 95% confidence intervals (CI). A bivariate method and hierarchical summary receiver operating characteristic method were used to calculate the diagnostic test accuracy of the CNN model. Meta-regression and subgroup analyses were used to identify sources of heterogeneity.

RESULTS

A total of 28 studies were included in this systematic review and meta-analysis. Using still image-based analysis for the diagnosis of esophageal cancer or HGD provided a pooled sensitivity of 0.95 (95%CI: 0.92-0.97), pooled specificity of 0.92 (0.89-0.94), PLR of 11.5 (8.3-16.0), NLR of 0.06 (0.04-0.09), DOR of 205 (115-365), and AUC of 0.98 (0.96-0.99). When video-based analysis was used, a pooled sensitivity of 0.85 (0.77-0.91), pooled specificity of 0.73 (0.59-0.83), PLR of 3.1 (1.9-5.0), NLR of 0.20 (0.12-0.34), DOR of 15 (6-38) and AUC of 0.87 (0.84-0.90) were found. Prediction of invasion depth resulted in a pooled sensitivity of 0.90 (0.87-0.92), pooled specificity of 0.83 (95%CI: 0.76-0.88), PLR of 7.8 (1.9-32.0), NLR of 0.10 (0.41-0.25), DOR of 118 (11-1305), and AUC of 0.95 (0.92-0.96).

CONCLUSION

CNN-based image analysis in diagnosing esophageal cancer and HGD is an excellent diagnostic method with high sensitivity and specificity that merits further investigation in large, multicenter clinical trials.

Comparing N-acetylcysteine with sodium thiosulfate for relieving symptoms caused by Lugol's iodine chromoendoscopy: a randomized, double-blind trial

BACKGROUND AND AIMS

Lugol's iodine chromoendoscopy is an important method to detect esophageal squamous cell carcinoma. Sodium thiosulfate solution (STS) has been used to neutralize iodine after Lugol's chromoendoscopy; however, it is not available in many medical centers. The aim of the current study was to assess the efficacy of N-acetylcysteine solution (NAC) for relieving symptoms caused by Lugol's iodine chromoendoscopy.

METHODS

Patients were randomized to receive either STS or NAC after spraying Lugol's iodine solution on the esophagus. The neutralizing effects for residual iodine in the esophagus and gastric mucous pool were observed. The primary endpoint was the intensity of retrosternal pain and/or heartburn measured by a visual analog scale (VAS) score 30 minutes after chromoendoscopy. Secondary endpoints were the rate of patients with any adverse symptom, rate of moderate to severe retrosternal discomfort occurring, and heart rate variability between time points before and after chromoendoscopy.

RESULTS

The neutralization rates for residual iodine between the NAC and STS groups were not significantly different (P > .999). The difference of median VAS scores between the NAC and STS groups 30 minutes after chromoendoscopy was .0 (P = .719; 95% confidence interval, .0-.0), and the 95% confidence interval higher limit was .0, which was less than our prespecified margin of .5, concluding an noninferiority of NAC with regard to STS. There was no significant difference between the 2 groups regarding the rate of patients with any adverse symptom, rate of moderate to severe retrosternal discomfort, or heart rate variability at 5 minutes or 30 minutes after chromoendoscopy.

CONCLUSION

As a very easily accessible reagent in clinical circumstances, NAC can also alleviate mucosal irritation symptoms induced by Lugol's chromoendoscopy at similar efficacy as STS and can be routinely recommended. (Clinical trial registration number: NCT04764643.).

Comparative Efficacy and Safety of Anterograde vs. Retrograde Iodine Staining During Esophageal Chromoendoscopy: A Single-Center, Prospective, Parallel-Group, Randomized, Controlled, Single-Blind Trial

Background and Aim: Chromoendoscopy with iodine staining is an important diagnostic method for esophageal carcinomas or precancerous lesions. Unfortunately, iodine staining can be associated with numerous adverse events (AEs). We found that the starting position of spraying iodine solution is likely the main reason of causing AEs. We conducted this work to determine whether clinical outcomes from anterograde iodine staining were superior to those achieved after retrograde iodine staining.

Methods: A total of 134 subjects with a health risk appraisal flushing (HRA-F) score of >6 for esophageal cancer were randomly assigned to receive anterograde or retrograde iodine staining in the esophagus. The primary endpoints were the pain and the amount of iodine solution consumption. The secondary endpoints were iodine-staining effect, detection yield, and response to starch indicator.

Results: Nine patients suffered from pain and six patients revealed positive response to starch indicator in retrograde iodine-staining group; however, no patient reported pain (0/67) and all patients revealed a negative response to starch indicator in anterograde iodine-staining group. The amount of iodine solution consumption in anterograde iodine-staining group (4.97 mL) was significantly lower than that (6.23 mL) in retrograde iodine-staining group; however, the iodine-staining effect and detection yield were comparable between the two groups.

Conclusions: Anterograde iodine staining during Lugol chromoendoscopy appears to be as effective, but significantly safer than retrograde iodine staining.

White-light endoscopy is insufficient to distinguish between types of esophageal white lesions

OBJECTIVE

Esophageal white lesions (EWL) are commonly observed under upper endoscopy, while their clinical significance remains undetermined. The aim of this study was to identify the endoscopic characteristics of EWL and distinguish between different types of EWL.

METHODS

Consecutive patients with upper gastrointestinal complaints and participants admitted for health check-up who underwent esophagogastroduodenoscopy from October 2018 to August 2019 in a tertiary hospital were prospectively screened. EWL were detected under endoscopy and biopsy was performed for histological analysis. Participants' characteristics, lifestyle, esophageal motility and reflux monitoring variables were analyzed.

RESULTS

Of the 3641 consecutive participants screened, 303 of them aged 56.12 ± 10.95 years were found to have EWL (detection rate of 8.3%). More than one-third of them preferred hot drinks, eating pickled or spicy food, smoking and alcohol consumption and 5.3% had current or former upper gastrointestinal or head and neck cancers. The common endoscopic appearance of the EWL (2.9 mm ± 1.2 mm in diameter) included slightly elevated plaque, translucent white in color, with a clear border, round or oval in shape, and a scaly, rough or smooth surface. Histology showed low-grade intraepithelial dysplasia in 13 cases, leukoplakia in 10 and intestinal metaplasia in one. No significant differences were found between the histological findings and endoscopic manifestations of EWL.

CONCLUSIONS

EWL are not uncommon in daily endoscopic examination, with some of them being precancerous lesions. Conventional white-light endoscopy is insufficient to identify EWL, while histological assessment is important. Further studies using advanced endoscopic techniques with long-term follow-up are needed.

Comprehensive mutational analysis of background mucosa in patients with Lugol-voiding lesions

Somatic mutations including the background mucosa in patients with Lugol-voiding lesions (LVLs) are still not well known. The aim of this study was to evaluate the somatic mutations of the background mucosa in patients with LVLs (Squamous cell carcinoma (SCC), intraepithelial neoplasia (IN), and hyperplasia). Twenty-five patients with LVLs (9 with SCC, 6 with IN, and 10 with hyperplasia) were included. A targeted sequence was performed for LVLs and background mucosa using an esophageal cancer panel. Each mutation was checked whether it was oncogenic or not concerning OncoKB. In LVLs, TP53 was the most dominant mutation (80%). Furthermore, 72% of TP53 mutations was putative drivers. In background mucosa, NOTCH1 was the most dominant mutation (88%) and TP53 was the second most dominant mutation (48%). Furthermore, 73% of TP53 mutations and 8% of NOTCH1 mutations were putative drivers. Putative driver mutations of TP53 had significantly higher allele frequency (AF) in SCC than in IN and hyperplasia. Conversely, putative driver mutations of NOTCH1 did not have a significant accumulation of AF in the progression of carcinogenesis. Furthermore, in SCC, AF of TP53 mutations was significantly higher in LVLs than in background mucosa, but not in IN and hyperplasia. Regarding NOTCH1, a significant difference was not observed between LVLs and background mucosa in each group. The background mucosa in patients with LVLs already had putative driver mutations such as TP53 and NOTCH1. Of these two genes, TP53 mutation could be the main target gene of carcinogenesis in esophageal SCC. Clinical Trials registry: UMIN000034247.

Ability of artificial intelligence to detect T1 esophageal squamous cell carcinoma from endoscopic videos and the effects of real-time assistance

Diagnosis using artificial intelligence (AI) with deep learning could be useful in endoscopic examinations. We investigated the ability of AI to detect superficial esophageal squamous cell carcinoma (ESCC) from esophagogastroduodenoscopy (EGD) videos. We retrospectively collected 8428 EGD images of esophageal cancer to develop a convolutional neural network through deep learning. We evaluated the detection accuracy of the AI diagnosing system compared with that of 18 endoscopists. We used 144 EGD videos for the two validation sets. First, we used 64 EGD observation videos of ESCCs using both white light imaging (WLI) and narrow-band imaging (NBI). We then evaluated the system using 80 EGD videos from 40 patients (20 with superficial ESCC and 20 with non-ESCC). In the first set, the AI system correctly diagnosed 100% ESCCs. In the second set, it correctly detected 85% (17/20) ESCCs. Of these, 75% (15/20) and 55% (11/22) were detected by WLI and NBI, respectively, and the positive predictive value was 36.7%. The endoscopists correctly detected 45% (25–70%) ESCCs. With AI real-time assistance, the sensitivities of the endoscopists were significantly improved without AI assistance (p < 0.05). AI can detect superficial ESCCs from EGD videos with high sensitivity and the sensitivity of the endoscopist was improved with AI real-time support.

Composition and consistence of the bacterial microbiome in upper, middle and lower esophagus before and after Lugol's iodine staining in the esophagus cancer screening

BACKGROUND

Esophageal bacteria, as the integral composition of human ecosystem, have been reported to be associated with esophageal lesions. However, few studies focus on microbial compositions in different esophageal segments, especially after Lugol's iodine staining (LIS) in the endoscopic examination for the screening of esophageal cancer. We aim to investigate the composition of the bacterial microbiome in upper, middle and lower esophagus and if LIS would affect the detection of bacteria.

METHODS

A total of 141 fasting samples including the upper, middle and lower esophagus from 27 participants were collected by brushing the mucosal surface of the esophagus before (Eso) and after (Lug) LIS. Bacterial V3-V4 region of 16S rRNA gene was amplified and sequenced by Illumina's sequencing platform.

RESULTS

The top six abundant bacterial phyla taxa among three locations from both Eso and Lug groups were Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria, Fusobacteria and TM7. In terms of genera, the bacterium in three locations from two groups was all characterized by a highest relative abundance of Streptococcus. Bacteria diversity and the relative abundance between Eso and Lug were comparable (p > .05). Bacteria diversity was consistent in different esophageal locations within the individual.

CONCLUSION

The bacterial microbiome in healthy esophagus are highly diverse and consistent even among three physiological sites at all clades. Lugol's iodine staining would not change local microenvironment in term of microbial composition. These findings provide an essential baseline for future studies investigating local and systemic bacterial microbiome and esophageal diseases.

Tolerability and efficacy of the concentration of iodine solution during esophageal chromoendoscopy: a double-blind randomized controlled trial

BACKGROUND AND AIMS

Esophageal chromoendoscopy with iodine solution is an important diagnostic method for the detection of superficial esophageal cancer. However, the concentration of iodine solution has differed among reports. This study aimed to evaluate patient discomfort with different iodine concentrations.

METHODS

We performed a prospective, double-blind, randomized study. We prospectively enrolled and analyzed 77 patients who were at high risk for esophageal carcinoma and scheduled to undergo EGD from March 2018 to January 2019. All patients were divided into 2 groups before the procedure to compare pain measurements: a 1% iodine solution group (group A) and a 2% iodine solution group (group B). The primary endpoint of this study was the difference in pain measurement between 1% and 2% iodine solution chromoendoscopy. Secondary endpoints were safety, detection yield, and color evaluation based on both the endoscopist's survey and color values, as determined using the Commission Internationale de l'Eclairage (CIELAB, Vienna, Austria) color evaluation system, in the iodine-faded and iodine-stained area of each group.

RESULTS

Heartburn and retrosternal pain in group A were significantly lower than those in group B (P = .02). Eleven patients reported heartburn and retrosternal pain (group A, 2; group B, 9). Four patients reported pain above the sternal angle and 7 below the sternal angle. There was no significant difference between the 2 groups with regard to detection yield, color evaluation by the endoscopist's assessment, or color values. No patients had any adverse events, and all safely completed this study.

CONCLUSIONS

The 2% iodine solution resulted in significantly greater pain than the 1% iodine solution, and the color of the stained esophageal images of each group was the same from this study. Therefore, the 1% iodine solution is recommended for esophageal chromoendoscopy. (Clinical trial registration number: UMIN 000029796.).

The Current Situation of Esophageal Cancer Staging and Perioperative Strategies Determination in Central and Southern China: A Cross Sectional Survey

Purpose: We aim to investigate the current esophageal cancer staging according to the 7th edition TNM classification for esophageal carcinoma proposed by American Joint Committee on Cancer (AJCC) among oncology-related physicians in China. Methods: A specifically-designed 14-item questionnaire was distributed to 366 doctors who were working with esophageal cancer patients. We collected and analyzed the feedbacks and explored the possible associations within different departments, including thoracic surgery, the internal medicine of gastroenterology, oncology, and/ radiotherapy in eight different hospitals from central and southern China. Results: Among all the responses, 31.42% of them were from thoracic surgery department, 40.44% were from oncology and/or radiation therapy and 28.14% were from the internal medicine of gastroenterology, respectively. Surprisingly, in total 66.12% of all the physicians were unaware that the 7th edition of esophageal carcinoma TNM classification was released in 2009; only 21.86 and 16.67% of physicians recognized cervical nodes and celiac nodes as regional lymph nodes. Furthermore, 67.21% physicians didn't know that tumor location, histologic grade, and histopathology were accepted as new prognostic factors in the latest TNM system; and 51.37% physicians could not determine the correct TNM classification of esophagogastric junction cancers. Intriguingly, over 50% of them could still design appropriate perioperative strategies. Conclusions: The 7th edition of the TNM classification for esophageal carcinoma is poorly recognized and understood in central and southern China, which might contribute to the relatively low rates of appropriate perioperative procedures applied for esophageal cancer patients.

Rapid detection of superficial head and neck squamous cell carcinoma by topically spraying fluorescent probe targeting dipeptidyl peptidase-IV

BACKGROUND

A fluorescent probe glutamylprolyl hydroxymethyl rhodamine green (EP-HMRG), which becomes fluorescent after cleavage by dipeptidyl peptidase-IV (DPP-IV), has been reported to be useful for the detection of esophageal cancer. Thus, we investigated whether head and neck squamous cell carcinoma (HNSCC) can be detected by spraying EP-HMRG.

METHODS

Fluorescence imaging of 17 cases of HNSCCs resected using endoscopic or surgical resection was performed ex vivo after spraying EP-HMRG, and then the fluorescence intensity of the tumors and normal mucosa were measured.

RESULTS

Iodine-voiding lesions became fluorescent within a few minutes after the application of EP-HMRG in 12 resected tumors without a history of radiotherapy but this was not observed in the normal mucosa. Fluorescence intensity in tumor lesions was significantly higher than normal lesions. However, 5 other tumors that developed after radiotherapy did not have sufficient contrast against normal mucosa.

CONCLUSION

Fluorescence imaging with EP-HMRG would be useful for rapid detection of superficial HNSCC without a history of radiotherapy.

Endoscopic Management of Early Adenocarcinoma and Squamous Cell Carcinoma of the Esophagus: Screening, Diagnosis, and Therapy

Because the esophagus is easily accessible with endoscopy, early diagnosis and curative treatment of esophageal cancer is possible. However, diagnosis is often delayed because symptoms are not specific during early stages of tumor development. The onset of dysphagia is associated with advanced disease, which has a survival at 5 years lower than 15%. Population screening by endoscopy is not cost-effective, but a number of alternative imaging and cell analysis technologies are under investigation. The ideal screening test should be inexpensive, well tolerated, and applicable to primary care. Over the past 10 years, significant progress has been made in endoscopic diagnosis and treatment of dysplasia (squamous and Barrett's), and early esophageal cancer using resection and ablation technologies supported by evidence from randomized controlled trials. We review the state-of-the-art technologies for early diagnosis and minimally invasive treatment, which together could reduce the burden of disease.

Fluorescent imaging of superficial head and neck squamous cell carcinoma using a γ-glutamyltranspeptidase-activated targeting agent: a pilot study

Background

Detecting superficial head and neck squamous cell carcinoma (HNSCC) by endoscopy is challenging because of limited morphological hallmarks, and iodine cannot be applied to head and neck lesions due to severe mucosal irritation. γ-glutamyltranspeptidase (GGT), a cell surface enzyme, is overexpressed in several cancers, and it has been reported that γ-glutamyl hydroxymethyl rhodamine green (gGlu-HMRG), a fluorescent targeting agent which can be enzymatically activated and becomes fluorescent after cleavage of a GGT-specific sequence, can be activated within a few minutes after application to animal models. We investigated whether early HNSCC can be detected by applying gGlu-HMRG to clinical samples.

Methods

gGlu-HMRG was applied to four HNSCC cell lines, and fluorescence was observed by fluorescence microscopy and flow cytometry. Immunohistological examination was performed in three recent cases of endoscopic submucosal dissection (ESD) to investigate GGT expression. Fluorescence imaging with gGlu-HMRG in eight clinical samples resected by ESD or surgery was performed, and fluorescence intensity of tumor and normal mucosa regions of interest (ROI) was prospectively measured.

Results

All four gGlu-HMRG-applied cell lines emitted green fluorescence. Immunohistological examination demonstrated that GGT was highly expressed in HNSCC of the recent three ESD cases but barely in the normal mucosa. Fluorescence imaging showed that iodine-voiding lesions became fluorescent within a few minutes after application of gGlu-HMRG in all eight resected tumors. Tumor ROI fluorescence intensity was significantly higher than in the normal mucosa five minutes after gGlu-HMRG application.

Conclusions

Fluorescence imaging with gGlu-HMRG would be useful for early detection of HNSCC.

Detection of superficial esophageal squamous cell neoplasia by chromoendoscopy-guided confocal laser endomicroscopy

AIM: To evaluate the diagnostic potential of Lugol’s chromoendoscopy-guided confocal laser endomicroscopy (CLE) in detecting superficial esophageal squamous cell neoplasia (ESCN).

METHODS: Between December 2008 and September 2010, a total of 52 patients were enrolled at the Chinese PLA General Hospital in Beijing, China. First, Lugol’s chromoendoscopy-guided CLE was performed in these patients and the CLE in vivo histological diagnosis was recorded. Then, chromoendoscopy-guided biopsy was performed in the same patients by another endoscopist who was blinded to the CLE findings. Based on the biopsy and CLE diagnosis, en bloc endoscopic resection was performed. The CLE in vivo diagnosis and the histological diagnosis of biopsy of ESCN were compared, using a histological examination of the endoscopic resection specimens as the standard reference.

RESULTS: A total of 152 chromoendoscopy-guided biopsies were obtained from 56 lesions. In the 56 lesions of 52 patients, a total of 679 CLE images were obtained vs 152 corresponding biopsies. The sensitivity, specificity, negative predictive value and positive predictive value of chromoendoscopy-guided CLE compared with biopsy were 95.7% vs 82% (P < 0.05), 90% vs 70% (P < 0.05), 81.8% vs 46.7% (P < 0.05), and 97.8% vs 92.7% (P > 0.05), respectively. There was a significant improvement in sensitivity, specificity, negative predictive value, and accuracy when comparing chromoendoscopy-guided CLE with biopsy.

CONCLUSION: Lugol’s chromoendoscopy-guided CLE is a real-time, non-invasive endoscopic diagnostic technology; the accuracy of the detection of superficial ESCN is equivalent to or may be superior to biopsy histology.

Lugol chromoendoscopic screening for esophageal dysplasia/early squamous cell carcinoma in patients with esophageal symptoms in low-risk region in China

Detection of esophageal dysplasia/early esophageal squamous cell carcinoma (ESCC) is essential for improving 5-year survival. The aim of this prospective study was to evaluate whether Lugol chromoendoscopy improves the detection of esophageal dysplasia/early ESCC in patients with esophageal symptoms in a low-incidence region in China. Eligible patients were randomly assigned into two groups who received routine endoscopy or Lugol chromoendoscopy. During endoscopy, between one and five biopsies were taken from visible lesions for routine endoscopy, or unstained areas of >0.5 cm in diameter for Lugol chromoendoscopy. In total, 812 patients were enrolled, 395 for routine endoscopy and 417 for Lugol chromoendoscopy. The overall detection rate of esophageal dysplasia/early ESCC was 10.6% (86/812), the detection rates were 7.3% (29/395) and 13.7% (57/417) in routine and chromoendoscopy groups, respectively (χ²=8.58, P=0.003). The detection rates were 8.3% (48/580), 17.2% (17/99) and 16.5% (22/133), respectively, in patients with reflux, dysphagia and globus sensation symptoms. In the chromoendoscopy group, 213 patients had unstained lesions of >0.5 cm, the detection rates of dysplasia/early carcinoma were 5.3% (4/76) in those with lesions of 0.5-1.0 cm, and 37.2% (51/137) in those with lesions >1.0 cm (χ²=21.46, P<0.001). These results indicate that Lugol chromoendoscopy improves the detection rate of esophageal dysplasia/early carcinoma in patients with esophageal symptoms compared with routine endoscopy. We propose that Lugol chromoendoscopy must therefore be considered in addition to routine endoscopy in patients with esophageal symptoms.

Tolerability of magnifying narrow band imaging endoscopy for esophageal cancer screening

AIM: To compare the tolerability of magnifying narrow band imaging endoscopy for esophageal cancer screening with that of lugol chromoendoscopy.

METHODS: We prospectively enrolled and analyzed 51 patients who were at high risk for esophageal cancer. All patients were divided into two groups: a magnifying narrow band imaging group, and a lugol chromoendoscopy group, for comparison of adverse symptoms. Esophageal cancer screening was performed on withdrawal of the endoscope. The primary endpoint was a score on a visual analogue scale for heartburn after the examination. The secondary endpoints were scale scores for retrosternal pain and dyspnea after the examinations, change in vital signs, total procedure time, and esophageal observation time.

RESULTS: The scores for heartburn and retrosternal pain in the magnifying narrow band imaging group were significantly better than those in the lugol chromoendoscopy group (P = 0.004, 0.024, respectively, ANOVA for repeated measures). The increase in heart rate after the procedure was significantly greater in the lugol chromoendoscopy group. There was no significant difference between the two groups with respect to other vital sign. The total procedure time and esophageal observation time in the magnifying narrow band imaging group were significantly shorter than those in the lugol chromoendoscopy group (450 ± 116 vs 565 ± 174, P = 0.004, 44 ± 26 vs 151 ± 72, P < 0.001, respectively).

CONCLUSION: Magnifying narrow band imaging endoscopy reduced the adverse symptoms compared with lugol chromoendoscopy. Narrow band imaging endoscopy is useful and suitable for esophageal cancer screening periodically.

Usefulness of non-magnifying narrow-band imaging in screening of early esophageal squamous cell carcinoma: a prospective comparative study using propensity score matching

OBJECTIVES

The usefulness of non-magnifying endoscopy with narrow-band imaging (NBI; NM-NBI) in the screening of early esophageal squamous cell carcinoma (SCC) and high-grade intraepithelial neoplasia (HGIN) remains unclear. Here, we aimed to compare NM-NBI and chromoendoscopy with iodine staining (CE-Iodine) in terms of the diagnostic performance, and to evaluate the usefulness of NM-NBI in detecting early esophageal SCC.

METHODS

We prospectively enrolled 202 consecutive patients (male/female=180/22; median age, 67 years) with high-risk factors for esophageal SCC. All patients received endoscopic examination with NM-NBI and CE-Iodine to screen for early esophageal SCC or HGIN. We conducted the examinations sequentially, and calculated the accuracy, sensitivity, and specificity through a per-lesion-based analysis. A propensity score matching analysis was performed to reduce the effects of selection bias, and we compared the respective outcomes according to NM-NBI and CE-Iodine after matching.

RESULTS

The accuracy, sensitivity, and specificity of NM-NBI were 77.0, 88.3, and 75.2%, respectively, and those for unstained areas by CE-Iodine were 68.0, 94.2, and 64.0, respectively. The accuracy and specificity of NM-NBI were superior to those of CE-Iodine (P=0.03 and P=0.01, respectively). However, the sensitivity did not significantly differ between NM-NBI and CE-Iodine (P=0.67). The accuracy and specificity of NM-NBI before matching were superior to those of CE-Iodine after matching (P=0.04 and P=0.03).

CONCLUSIONS

NM-NBI was useful and reliable for the diagnosis of esophageal SCC and can be a promising screening strategy for early esophageal SCC.

Effectiveness of unsedated transnasal endoscopy with white-light, flexible spectral imaging color enhancement, and lugol staining for esophageal cancer screening in high-risk patients

BACKGROUND AND AIMS

Transnasal endoscopy (TNE) has been proposed to screen for esophageal squamous cell cancer (ESCC) in Asia. This study aimed to assess the feasibility and tolerance of Brazilian patients to undergo unsedated TNE for screening, the prevalence of ESCC in this population, and the effectiveness of white-light endoscopy (WLE) and digital chromoendoscopy [flexible spectral imaging color enhancement (FICE)] to diagnose esophageal neoplasia.

PATIENTS AND METHODS

This was a diagnostic test study that enrolled patients with head and neck squamous cell cancer (HNSCC) referred to ESCC screening. Patients' tolerance was rated by a numeric pain intensity scale. Interventions included unsedated TNE with WLE and FICE examination of the esophagus, in a tandem manner with blinded operators, followed by lugol chromoscopy. Performance of WLE and FICE for neoplasia detection was compared with the reference standard (lugol chromoscopy plus histology).

RESULTS

A total of 106 patients were recruited. TNE was feasible in 99.1%, and 92% of the patients rated the discomfort as absent or minimal. Thirteen ESCC were detected (12.3%), with 10 early cancers (77%). The tests showed an excellent performance and there was no difference between WLE (sensitivity 92.3%, specificity 98.9%, accuracy 98.1%, area under curve 0.995) and FICE (sensitivity 100%, specificity 98.9%, accuracy 99%, area under curve 0.956) for esophageal neoplasia detection.

CONCLUSIONS

Unsedated TNE is a feasible, well accepted, and efficient diagnostic tool for the screening of ESCC. The elevated rate of esophageal neoplasia strengthens the recommendations to screen patients with HNSCC. The yields of WLE and FICE were similar for ESCC detection.

Narrow band imaging with magnification can pick up esophageal squamous cell carcinoma more efficiently than lugol chromoendoscopy in patients after chemoradiotherapy

Aim. Little is known about the usefulness of narrow band imaging (NBI) for surveillance of patients after chemoradiotherapy for esophageal neoplasia. Its usefulness in detecting esophageal squamous cell carcinoma (SCC) or high-grade intraepithelial neoplasia (HGIN) in these patients was retrospectively compared to Lugol chromoendoscopy. Patients and Methods. We assessed the diagnostic ability of NBI with magnification based on the biopsy specimens obtained from iodine-unstained lesions. Seventy-two iodine-unstained lesions were biopsied and consecutively enrolled for this study. The lesions were divided into NBI positive and NBI negative. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of NBI with magnification and PPV of Lugol chromoendoscopy was calculated using histological assessment as a gold standard. Results. Forty-six endoscopic examinations using NBI with magnification followed by Lugol chromoendoscopy were performed to 28 patients. The prevalence of SCC and HGIN was 21.4%. Sensitivity, specificity, PPV, NPV, and accuracy of NBI were 100.0%, 98.5%, 85.7%, 100%, and 98.6%, respectively. On the contrary, PPV of Lugol chromoendoscopy were 8.3%. Compared to Lugol chromoendoscopy, NBI with magnification showed equal sensitivity and significantly higher PPV (P < 0.0001). Conclusion. NBI with magnification would be able to pick up esophageal neoplasia more efficiently than Lugol chromoendoscopy in patients after chemoradiotherapy.

Endoscopic resection of co-existing severe dysplasia and a small esophageal leiomyoma

Leiomyoma is the most common benign mesenchymal tumor of the esophagus. A small leiomyoma covered with endoscopically normal mucosa has a characteristic endoscopic ultrasonographic appearance, slow growth rate, and negligible risk of malignant transformation; therefore the histology does not need to be proven. Synchronous tumors such as an epithelial tumor and small subepithelial tumor in the upper gastrointestinal tract are uncommon. We describe a case with a co-existing small leiomyoma and severe dysplasia in the esophagus which were completely resected by endoscopic mucosal resection.

Avanços na abordagem do carcinoma precoce de esôfago

Nos países ocidentais, o carcinoma de células escamosas de esôfago (CCE) geralmente é detectado em estágio avançado, quando as possibilidades de cura são remotas e o prognóstico reservado. Entretanto, nos anos recentes, ocorreu uma série de avanços na abordagem do CCE de esôfago, tais como a identificação dos grupos de risco para o surgimento desta neoplasia; o uso da endoscopia de alta resolução e cromoendoscopia com lugol favorecendo o diagnóstico do CCE em estágios iniciais; e o desenvolvimento de técnicas endoscópicas de ressecção tumoral endoluminal em monobloco denominada dissecção endoscópica de submucosa. Este progresso tem possibilitado a aplicação do tratamento endoscópico minimamente invasivo com potencial curativo em pacientes selecionados com CCE superficial de esôfago. O presente artigo de revisão, elaborado por um grupo multicêntrico internacional, tem como objetivo primário contribuir para o entendimento dos principais avanços recentes ocorridos no manejo do CCE precoce de esôfago. Como objetivo secundário, pretende propiciar uma revisão detalhada e minuciosa da estratégia técnica de DES desenvolvida pelos experts japoneses, de forma a colaborar para a difusão deste conceito e a incorporação destas tecnologias na Medicina Brasileira e Latino-americana.

Update on endoscopic diagnosis, management and surveillance strategies of esophageal diseases

In the last few decades, upper gastrointestinal endoscopy has become the most complementary test for investigation of esophageal diseases. Its accessibility and safety guarantee wide clinical utilization in patients with suspected benign and malignant diseases of the esophagus. Recent technological advances in endoscopic imaging and tissue analysis obtained from the esophagus have been useful to better understand and manage highly relevant diseases such as gastroesophageal reflux disease, eosinophilic esophagitis and esophageal cancer. Using endoscopy to elucidate esophageal disorders in children has been another field of intensive and challenging research. This editorial highlights the latest advances in the endoscopic management of esophageal diseases, and focuses on Barrett's esophagus, esophageal cancer, eosinophilic esophagitis, as well as esophageal disorders in the pediatric population.

Esophageal squamous cell carcinoma - precursor lesions and early diagnosis

Squamous cell carcinoma of the esophagus (SCCE) carries a poor prognosis due to late diagnosis. Early detection is highly desirable, since surgical and endoscopic resection offers the only possible cure for esophageal cancer. Population screening should be undertaken in high risk areas, and in low or moderate risk areas for people with risk factors (alcoholics, smokers, mate drinkers, history of head and neck cancer, achalasia and lye stricture of the esophagus). Esophageal balloon cytology is an easy and inexpensive sampling technique, but the current methods are insufficient for primary screening due to sampling errors. Conventional endoscopy with biopsy remains the standard procedure for the identification of pre-malignant and early malignant changes in esophageal mucosa and endoscopic detection. It may be enhanced by several techniques such as dye and optic chromoendoscopy, magnifying endoscopy, and optical-based spectroscopic and imaging modalities. Since more than 80% of SCCE deaths occur in developing countries, where expensive techniques such as narrow band imaging (NBI) and autofluorescence imaging are unavailable, the most cost-effective tool for targeting biopsies may be Lugol dye chromoendoscopy, since it is easy, accurate, inexpensive and available worldwide. In ideal conditions, or in developed countries, is it reasonable to think that optimal detection will require a combination of techniques, such as the combination of Lugol’s chromoendoscopy and NBI to identify esophageal areas that require further characterization by a high resolution technique. The efficacy and cost-effectiveness will determine whether these modalities will become part of standard endoscopy practice.

Autofluorescence imaging endoscopy for screening of esophageal squamous mucosal high-grade neoplasia: a phase II study

BACKGROUND AND AIM

Few prospective studies examining the efficacy of autofluorescence imaging (AFI) screening for esophageal cancer have been reported. This study aimed to investigate the diagnostic value of AFI endoscopy for the screening of squamous mucosal high-grade neoplasia of the esophagus, performed by experienced and less-experienced endoscopists.

METHODS

Patients with a history of esophageal neoplasia or head and neck cancer underwent AFI endoscopic screening, followed by chromoendoscopy using iodine staining as the reference standard. The primary outcome was the sensitivity of AFI for detecting new squamous mucosal high-grade neoplasias. The secondary outcome was the positive predictive value (PPV) of AFI.

RESULTS

Of a total 364 patients who underwent endoscopic examination, 43 new mucosal high-grade neoplasias were detected. The sensitivities of AFI in the experienced and less-experienced endoscopist groups were 71% (95% confidence interval [CI]: 55-87%) and 50% (95% CI: 32-68%), respectively. The PPV of AFI in the experienced and the less-experienced endoscopist groups were 25% (95% CI: 16-34%) and 26% (95% CI: 15-37%), respectively. The sensitivity of AFI in lesions ≤ 10 mm (31%, 5/16 lesions) was significantly lower than that in lesions > 10 mm (78%, 21/27 lesions) (P = 0.003).

CONCLUSIONS

The sensitivity of AFI for the detection of new squamous mucosal high-grade neoplasias, and its PPV, were both low. Based on these results, a randomized study to compare AFI with standard techniques is not justified.

Development of squamous neoplasia in esophageal iodine-unstained lesions and the alcohol and aldehyde dehydrogenase genotypes of Japanese alcoholic men

We investigated the development of esophageal neoplasia in biopsy specimens of the distinct iodine-unstained lesions (DIULs) ≥ 5 mm detected in 280 of 2,115 Japanese alcoholic men who underwent screening by esophageal iodine staining. Low-grade intraepithelial neoplasia (LGIN) was diagnosed in 155 of them, high-grade intraepithelial neoplasia (HGIN) in 57, and invasive SCC in 35. The size of the DIULs increased with the degree of neoplasia. Most LGINs were flat and were missed before iodine staining. Some DIULs became a light pink color (PC) about 2 min after staining, and 2.6, 56.1 and 96.0% of the LGIN, HGIN and invasive SCC lesions, respectively, were PC-sign-positive. Multiple DIULs of any size markedly increased the risk of LGIN [adjusted OR (95%CI) = 10.1 (7.12-14.5)], HGIN [27.9 (14.6-53.4)] and invasive SCC [21.6 (10.1-46.4)], and were strongly associated with the presence vs. absence of DIULs ≥ 5 mm [13.3 (9.21-19.1)], inactive heterozygous aldehyde dehydrogenase-2 (ALDH2*1/*2) vs. ALDH2*1/*1 [2.60 (1.79-3.78)], and less-active alcohol dehydrogenase-1B (ADH1B*1/*1) vs. ADH1B*2 allele [2.61 (1.87-3.64)]. The combination of ALDH2*1/*2 and ADH1B*1/*1 synergistically increased the risk of LGIN [4.53 (2.17-9.47)], HGIN [10.4 (4.34-24.7)] and invasive SCC [21.7 (7.96-59.3)]. Esophageal neoplasia developed at earlier ages in those with ALDH2*1/*2. Biopsy-proven HGIN was diagnosed as invasive SCC in 15 (39.5%) of 38 patients after endoscopic mucosectomy or surgery. In conclusion, large size, non-flat appearance, positive PC sign and multiplicity of DIULs and ALDH2*1/*2 and ADH1B*1/*1 were associated with development of esophageal neoplasia in Japanese alcoholics. Biopsy-proven HGIN should be totally resected for both diagnostic and therapeutic purposes.

Evaluation of double vital staining with lugol's iodine and methylene blue in diagnosing superficial esophageal lesions

OBJECTIVE

To evaluate the accuracy of double vital staining with lugol's iodine and methylene blue in the diagnosis of superficial esophageal lesions.

METHODS

Doubtful superficial esophageal lesions identified with conventional endoscope were sprayed with 3% lugol's iodine and 0.5% methylene blue in order and observed in detail after each staining. Depending on the mucosal staining, biopsy specimen was obtained and underwent pathological examination.

RESULTS

Using conventional endoscope, we found 356 lesions in 297 patients, among which 179 were esophageal squamous cell carcinoma and precancerous lesions (CAPs) (including 71 early esophageal squamous cell carcinoma, 23 esophageal high-grade intraepithelial neoplasias, 85 esophageal low-grade intraepithelial neoplasias) and 177 were non-cancer non-precancerous lesions (NCNPs) (i.e. esophagitis and esophageal squamous cell hyperplasia). Most of CAPs were lightly stained or unstained, while NCNPs were hyperstained after lugol's iodine stained. The specificity, sensitivity, positive predictive value, negative predictive value and accuracy of lugol's lightly stained and unstained for identifying CAPs were 34.5%, 100%, 60.7%, 100% and 67.4%, respectively. Most of CAPs were lightly stained or hyperstained, while NCNPs were unstained after double vital staining. The specificity, sensitivity, positive predictive value, negative predictive value and accuracy of double vital staining lightly stained and hyperstained for identifying CAPs were 97.7%, 100%, 97.8%, 100% and 98.9%, respectively. The accuracy of double vital staining for identifying CAPs was higher than that of lugol's iodine stained (p = 0.000).

CONCLUSION

The double staining with lugol's iodine and methylene blue significantly improves the detection and diagnosis of early esophageal squamous cell CAPs.

Prospective evaluation of narrow-band imaging endoscopy for screening of esophageal squamous mucosal high-grade neoplasia in experienced and less experienced endoscopists

Narrow-band imaging (NBI) is a novel, noninvasive optical technique that uses reflected light to visualize the organ surface. However, few prospective studies that examine the efficacy of NBI screening for esophageal cancer have been reported. To compare the diagnostic yield of NBI endoscopy for screening of squamous mucosal high-grade neoplasia of the esophagus between experienced and less experienced endoscopists. Patients with a history of esophageal neoplasia or head and neck cancer received NBI endoscopic screening for esophageal neoplasia followed by chromoendoscopy using iodine staining. Biopsy specimens were taken from iodine-unstained lesions and the histological results of mucosal high-grade neoplasias served as the reference standard. The primary outcome was the sensitivity of NBI for detecting new lesions. The secondary outcome was the positive predictive value of NBI and the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of NBI in a per lesion basis. A total of 350 patients (170 by experienced endoscopists and 180 by less experienced endoscopists) underwent endoscopic examination. A total of 42 new mucosal high-grade neoplastic lesions (25 in the experienced endoscopist group and 17 in the less experienced endoscopist group) were detected. In the per-lesion-based analysis, the sensitivity was significantly higher in the experienced endoscopist group (100%; 25/25) compared with the less experienced endoscopist group (53%; 9/17) (P < 0.001). The positive predictive value of NBI was higher in the experienced endoscopist group than in the less experienced endoscopist group (45%, 25/55 vs. 35%, 9/26), although the difference was not significant (P = 0.50). The sensitivity of NBI in the less experienced endoscopist group was 43% in the former half of patients, and increased to 60% in the latter half of patients. In the per-patient-based analysis, the sensitivity of NBI was significantly higher in the experienced endoscopist group (100%) than in the less experienced endoscopist group (100 vs. 69%, respectively; P = 0.04). The positive predictive values of the experienced endoscopist group and the less experienced endoscopist group were similar, and were 48 and 47%, respectively. In conclusion, compared with the gold standard of chromoendoscopy with iodine staining, the sensitivity of NBI for screening of mucosal high-grade neoplasia was 100% with the experienced endoscopists but was low with the less experienced endoscopists. Electronic chromoendoscopy with NBI is a promising screening tool in these high-risk patients with esophageal mucosal high-grade neoplasia, particularly when performed by endoscopists with experience of using NBI.

Significance of each narrow-band imaging finding in diagnosing squamous mucosal high-grade neoplasia of the esophagus

BACKGROUND AND AIM

Although narrow-band imaging (NBI) is used increasingly in clinical situations, the significance of each NBI finding has not been investigated. The primary endpoint of the present study was to identify the significant NBI findings to diagnose esophageal mucosal high-grade neoplasia.

METHODS

Between August 2007 and January 2009, we detected 59 new superficial esophageal lesions. The video images of NBI were recorded digitally. NBI findings such as brownish dots (dilated intra-epithelial papillary capillary loop [IPCL]), tortuous IPCL, elongated IPCL, caliber change in IPCL, variety in IPCL shapes, demarcation line, brownish epithelium, and protrusion or depression were evaluated using the video images. The association between each NBI finding and diagnosis of mucosal high-grade neoplasia, and intra- and interobserver agreement was evaluated.

RESULTS

In univariate analysis, brownish epithelium, brownish dots, tortuous IPCL, variety in IPCL shapes and demarcation line were associated significantly with diagnosis of mucosal high-grade neoplasia. In multivariate analysis, brownish epithelium and brownish dots were confirmed to be independent factors. Odds ratios were 25.5 (95% confidence interval [CI]: 2.4-268) for brownish epithelium and 19.3 (95% CI: 1.8-207.7) for brownish dots. Intraobserver agreement was substantial for brownish epithelium and brownish dots. Interobserver agreement was moderate in brownish epithelium and brownish dots.

CONCLUSIONS

Brownish epithelium and brownish dots were confirmed to be significant and reproducible NBI findings in the diagnosis of squamous mucosal high-grade neoplasia of the esophagus. Initial assessment of esophageal lesions should be done based on these findings.

Narrow-band imaging provides reliable screening for esophageal malignancy in patients with head and neck cancers

OBJECTIVES

The narrow-band imaging (NBI) system is a novel technology that enhances the visualization of microvasculature and mucosal patterns. The aim of this study was to assess the reliability of the NBI system for esophageal cancer screening in patients with head and neck cancers.

METHODS

A total of 142 patients with head and neck squamous cell carcinoma (SCC) were examined by NBI endoscopy, followed by Lugol chromoendoscopy between April 2006 and June 2008 at the Okayama University Hospital, Okayama, Japan. Detection of SCC and high-grade intraepithelial neoplasia (HGIN) was conducted.

RESULTS

The median age of the patients was 64 years (range: 29-86 years), and approximately three-fourths of all the patients were male. In total, 21 superficial lesions in 16 patients were detected by NBI endoscopy. Of these, 4 lesions were diagnosed histologically as SCC and 11 lesions as HGIN. An additional 22 Lugol-voiding lesions >or=5 mm were detected in 19 patients by Lugol chromoendoscopy. Although 1 of these lesions was diagnosed as HGIN, 21 lesions were diagnosed as low-grade intraepithelial neoplasia or lesions without atypical findings. The sensitivity of NBI endoscopy for detecting esophageal SCC and HGIN was 90.9% (95% confidence interval (CI), 58.7-99.8), specificity was 95.4% (95% CI, 90.3-98.3), and accuracy was 95.1% (95% CI, 90.1-98.0).

CONCLUSIONS

NBI seems to be useful and reliable for screening for esophageal SCC in patients with head and neck cancers.

Chromoendoscopy

Chromoendoscopy involves the use of stains or dyes during endoscopy to improve the visualization and characterization of the gastrointestinal mucosa. Its main clinical application is the detection of dysplasia or early cancer of the gastrointestinal tract in individuals with pre-malignant conditions or hereditary and environmental factors that predispose them to cancer. The utility of chromoendoscopy has been mostly studied in squamous cell carcinoma of the esophagus, Barrett's esophagus, gastric cancer, colorectal polyps, and chronic ulcerative colitis. Although chromoendoscopy has been shown to be feasible and safe, several limitations have prevented its widespread use in endoscopy. Despite this, chromoendoscopy remains a useful adjunct to standard white light endoscopy in the visualization of mucosal lesions, which may potentially improve tissue diagnosis and impact patient care.

Novel imaging modalities in the detection of oesophageal neoplasia

The prognosis of oesophageal neoplasia is dependent on the stage of the disease at the time of detection. Early lesions have an excellent prognosis in contrast to more advanced stages that usually have a dismal prognosis. Therefore, the early detection of these lesions is of the utmost importance. In recent years, several new techniques have been introduced to improve the endoscopic detection of early lesions. The most important improvement, in general, has been the introduction of high-resolution/high-definition endoscopy into daily clinical practice. The value of superimposing techniques such as chromoendoscopy, narrow band imaging and computed virtual chromoendoscopy onto high-resolution/high-definition endoscopy will have to be proven in randomised cross-over trials comparing these techniques with standard techniques. Important future adjuncts to white-light endoscopy serving as 'red-flag' techniques for the detection of early neoplasia may be broad field functional imaging techniques such as video autofluorescence endoscopy. In addition, real-time histopathology during endoscopy has become possible with endocytoscopy and confocal endomicroscopy. The clinical value of these techniques needs to be ascertained in the coming years.

Initial endoscopic description of esophageal squamous cell carcinomas

INTRODUCTION

The aim of this study was to evaluate initial endoscopic practices at diagnosis of esophageal squamous cell carcinoma in comparison with current recommendations. We wanted to develop a standard model for the endoscopy report which could be used in routine practice.

PATIENTS AND METHODS

From January 2000 to December 2002, 122 patients were hospitalized for esophageal squamous cell carcinoma. The initial endoscopic reports were reviewed retrospectively and compared with a model report established on the basis of current recommendations.

RESULTS

One hundred and nineteen reports were re-examined. The principal reason for performing the endoscopic examination was dysphagia in 73.9% of patients. Tumor measurements (height, upper and lower extremities) were recorded in 51.2%, 79% and 41% of reports, respectively. 14.4% of the analyzed reports concerned endoscopic procedures which were performed after a first endoscopic examination because the initial report provided an imprecise tumor description. Tissue samples taken during the initial endoscopy allowed a pathological diagnosis in 94.2% of patients. Lugol staining was performed in 2.5% of procedures.

CONCLUSION

Insufficiently rigorous reporting compromises the reliability of initial upper digestive endoscopic procedures. Application of a standardized model for routine practice would favor more complete reports, starting with the first procedure.

Endoscopic detection of early upper GI cancers

The detection of early-stage neoplastic lesions in the upper GI tract is associated with improved survival and the potential for complete endoscopic resection that is minimally invasive and less morbid than surgery. Despite technological advances in standard white-light endoscopy, the ability of the endoscopist to reliably detect dysplastic and early cancerous changes in the upper GI tract remains limited. In conditions such as Barrett's oesophagus, practice guidelines recommend periodic endoscopic surveillance with multiple biopsies, a methodology that is hindered by random sampling error, inconsistent histopathological interpretation, and delay in diagnosis. Early detection may be enhanced by several promising diagnostic modalities such as chromoendoscopy, magnification endoscopy, and optical spectroscopic/imaging techniques, as these modalities offer the potential to identify in real-time lesions that are inconspicuous under conventional endoscopy. The combination of novel diagnostic techniques and local endoscopic therapies will provide the endoscopist with much needed tools that can considerably enhance the detection and management of early stage lesions in the upper GI tract.

Cribado del carcinoma escamoso de esófago en población de riesgo

Together with adenocarcinoma, epidermoid esophageal carcinoma is the most clinically important neoplasm of the esophagus. Because of the low incidence of epidermoid esophageal carcinoma in the general population, strategies for its early diagnosis are not a priority compared with other neoplasms. However, because survival is low when the disease is diagnosed in symptomatic patients (less than 20% at 5 years), methods for its early diagnosis should be investigated. The use of cytology or Lugol chromoendoscopy in countries with a high incidence of epidermoid carcinoma or in individuals at increased risk (mainly alcoholics and smokers) has allowed early diagnosis and potentially curative treatment, substantially increasing life expectancy in this group of patients. These results should stimulate the evaluation and eventual implementation of programs to achieve early diagnosis and therefore greater survival in patients with epidermoid esophageal carcinoma in Western countries.

p53 immunoexpression: an aid to conventional methods in the screening of precursor lesions of squamous esophageal cancer in patients at high-risk?

INTRODUCTION

Squamous cell carcinoma of the esophagus (SCCE) is diagnosed late and carries a poor prognosis. Lugol chromoendoscopy (LC) has being shown a useful tool in the management of patients at high risk for SCCE. Biomarkers such as p53 protein expression may be present in the esophageal mucosa long before esophageal symptoms or lesions appear and may aid in early diagnosis. This study was carried out to investigate the p53 immunoexpression in esophageal mucosa of smokers and alcohol consumers and study its relationship with different degrees of histological findings and the role of LC to detect areas that express p53.

METHODS

Group 1: One hundred and eighty-two asymptomatic subjects at high risk for SCCE (consumption of more than 80 g of ethanol and 10 cigarettes/day for at least 10 years). Group 2: Twenty healthy volunteers who neither smoked nor consumed alcohol. Both groups underwent upper GI endoscopy plus LC, with biopsies of the esophageal mucosa. Expression of p53 protein was compared to histological findings.

RESULTS

Group 1: There was 25/182 (14%) Lugol's unstained areas. p53 protein was expressed in a stepwise fashion according to the severity of the histological findings: normal mucosa (12/103 or 12%), mild esophagitis (6/43 or 14%), moderate esophagitis (4/18 or 22%), severe esophagitis (1/3 or 33%), low-grade dysplasia (4/11 or 36%), high-grade dysplasia (2/2 or 100%) and squamous cell carcinoma (2/2 or 100%) (p=0.001). Nine in 25 (36%) patients with Lugol's unstained areas and 22/157 (14%) with normal appearing Lugol's stained mucosa expressed p53. Group 2: There was no Lugol unstained areas. The histological analysis and immunohistochemistry for p53 were normal with the exception of two patients that presented mild esophagitis and expressed p53. Unstained areas were 3.5 times (95% CI: 1.2-9.6) more likely to express p53 then stained ones. Alcoholics/smokers were 1.9 (95% CI: 0.4-8) times more likely to express p53 than non-alcoholics/non smokers.

CONCLUSIONS

In this study, we find an association between histological alterations, p53 expression and Lugol's unstained areas. It may point to a higher risk for SCCE. Smokers and alcohol drinkers with normal mucosa or chronic esophagitis that express p53 protein may represent an unrecognized sub-group of individuals that may benefit from surveillance or intervention.

Chromoendoscopy and magnification endoscopy for diagnosing esophageal cancer and dysplasia

Based on preliminary reports, the use of chromoendoscopy and magnification endoscopy appears to be a valuable adjunct to standard endoscopy for the detection and classification of metaplastic and dysplastic lesions of the esophagus. Ideally, the use of this technique would enable the endoscopist to rule in or out the presence of intestinal metaplasia and dysplastic/cancerous epithelium by obtaining only a minimal number of targeted biopsy specimens--or potentially taking no biopsies at all, which could transform upper endoscopy into a much more effective screening and surveillance tool. There are several problems with the use of chromoendoscopy and magnification endoscopy in the esophagus. This technique is operator-dependent (ie, dependent on the skill and experience of the endoscopist). Studies reporting the accuracy of chromoendoscopy remain mixed, especially for Barrett's esophagus and dysplasia, which is likely explained by differences in techniques and materials used in the investigations. Staining within the esophagus is often patchy and uneven. Poor spraying technique can exaggerate irregular uptake by the mucosa. There is a high false-positive rate when staining gastric-type epithelium or in the setting of inflammation. Areas of dysplasia or cancer might take up stain in an irregular manner or might not stain at all. Magnification only allows the endoscopist to observe small areas of mucosa at a time, increasing the overall difficulty of the procedure and procedure length. Currently, the greatest body of literature exists concerning the use of Lugol's solution for the diagnosis of squamous cell dysplasia/carcinoma of the esophagus and methylene blue for diagnosing Barrett's esophagus. If used consistently by practicing physicians, the accuracy of biopsies could be improved. If endoscopic ablative therapy for high-grade dysplasia and early carcinoma (eg, photodynamic therapy and endoscopic mucosal resection) becomes accepted, sensitive methods of detecting residual metaplastic or dysplastic epithelium after ablation will be needed to help guide additional endoscopic therapy. Chromoendoscopy and magnification endoscopy could prove helpful in this setting. Further research in this field needs to be performed. As a first step, a uniform classification system for staining and magnification patterns should be devised. Future studies could then be performed using consistent terminologies. More controlled investigations with larger numbers of patients must be performed before tissue staining and magnification endoscopy become a part of day-to-day endoscopic practice. Lugol's chromoendoscopy is a simple technique for the detection of synchronous squamous dysplasia and cancer, but a substantial amount of work remains to be performed for the validation of chromoendoscopy for the detection of Barrett's esophagus and dysplasia. The ultimate aim of chromoendoscopy and magnification endoscopy in the esophagus is to show improved outcomes (ie, early detection of cancer and improved survival). These goals have not yet been realized and will require welldesigned studies in the future.

High-resolution chromoendoscopy in the esophagus

The major role for chromoendoscopy in the esophagus is the identification of premalignant or early cancerous lesions. In combination with high-resolution or magnification endoscopes, chromoendoscopy can potentially increase the diagnostic yield of clinically relevant lesions. Preliminary data have indicated a good correlation of findings using this technique to histopathologic readings. The ultimate goal of chromoendoscopy in combination with high resolution/magnification endoscopy is the determination of histology without obtaining tissue samples. In this article we review the different stains, the technical aspects, and current data in esophageal chromoendoscopy. We summarize possible clinical applications of these techniques and future directions of their use in esophageal diseases.