Comparison of staging diagnosis by two magnifying endoscopy classification for superficial oesophageal cancer

A training program of a new simplified classification of magnified narrow band imaging for superficial esophageal squamous cell carcinoma

BACKGROUND AND AIM

Optimal staging of the invasion depth of superficial esophageal squamous cell carcinoma is vital before endoscopic treatment. A new simplified magnified narrow-band imaging (M-NBI) classification system based on vascular architecture has recently been developed by the Japan Esophageal Society; however, its validity remains uncertain.

METHODS

A total of 11 experienced and 11 inexperienced endoscopists were invited to join an endoscopic training program, which was composed of pretest, educational section, and post-test. The pretest and post-test sections included a set of endoscopic photos from 40 subjects with superficial esophageal squamous cell carcinoma with various invasion depths. Each subject appeared twice in the test, one with white-light imaging (WLI) only and the other with both WLI and M-NBI. The educational section included lectures and video demonstrations.

RESULTS

The accuracy of WLI alone and combined with M-NBI at baseline were 0.53, 0.57 and 0.43, 0.41 for the experienced and inexperienced endoscopists, respectively, which then improved to 0.57, 0.63 and 0.49, 0.52 after training. Inter-observer agreement (k-value) of WLI alone and combined WLI and M-NBI for the experienced and inexperienced endoscopists also improved from 0.61, 0.61, and 0.61, 0.53 to 0.68, 0.71, and 0.71, 0.59, respectively. Multivariate analysis revealed that the educational course but not experience in endoscopy, NBI, or magnification significantly improved the diagnostic accuracy. M-NBI had a significant additional benefit to WLI, with an improvement in accuracy from 36% to 56% for the cases with m3/sm1 cancers (P < 0.05).

CONCLUSIONS

A well-designed training program can improve the diagnostic accuracy in evaluating cancer invasion depth, with substantial agreement.

Comparative analysis of avascular areas in superficial esophageal squamous cell carcinomas using in vivo and ex vivo magnifying endoscopy

BACKGROUND AND STUDY AIMS

 An avascular area (AVA), one of the microvasculature changes in superficial esophageal cancers, appears when a tumor demonstrates a bulky growth pattern. We aimed to compare endoscopic and histopathological findings by observing formalin-fixed AVA specimens using magnifying endoscopy.

PATIENTS AND METHODS

 A prospective analysis was conducted on 16 patients with superficial esophageal cancer, including AVA, who underwent endoscopic submucosal dissection (ESD). Magnifying endoscopy and blue laser imaging were used to identify AVAs. After the ESD, the AVA width was measured on formalin-fixed specimens using magnifying endoscopy, and AVA thickness and depth were determined after hematoxylin and eosin staining using microscopy.

RESULTS

 Mean AVA widths of M1, M2, and M3/SM-lesions were 0.434, 0.578, and 0.835 mm, respectively (M1 vs. M2, P = 0.16; M2 vs. M3/SM-, P  = 0.07). Mean AVA thicknesses of M1, M2, and M3/SM-lesions were significantly different (0.176, 0.518, and 0.800 mm; M1 vs. M2, P < 0.01; M2 vs. M3/SM-, P  < 0.05). There was a significant correlation between AVA width and thickness.

CONCLUSIONS

 AVA size can be measured accurately on formalin-fixed specimens with magnifying endoscopy. AVA thickness can be useful for determining tumor depth.

Multicenter, prospective trial of white-light imaging alone versus white-light imaging followed by magnifying endoscopy with narrow-band imaging for the real-time imaging and diagnosis of invasion depth in superficial esophageal squamous cell carcinoma

BACKGROUND

Magnifying endoscopy with narrow-band imaging (ME-NBI) has been used to estimate the invasion depth of superficial esophageal squamous cell carcinoma (SESCC), but the real diagnostic power of ME-NBI remains unclear because of few prospective studies.

OBJECTIVES

To evaluate whether ME-NBI adds additional information to white-light imaging (WLI) for the diagnosis of invasion depth of SESCC.

DESIGN

Multicenter, prospective trial using real-time imaging and diagnosis.

SETTING

Seven Japanese institutions.

PATIENTS

Fifty-five patients with SESCC were enrolled from June 2011 to October 2013, and the results for 49 lesions were analyzed.

INTERVENTIONS

Patients underwent primary WLI followed by ME-NBI, and reports of primary WLI (WLI alone) were completed before secondary ME-NBI (WLI followed by ME-NBI). To standardize diagnosis among examiners, this trial was started after achievement of a mean κ value≥.6 among 11 participating endoscopists.

MAIN OUTCOME MEASUREMENTS

Diagnosis of invasion depth by each tool was divided into cancer limited to the epithelium and the lamina propria mucosa and cancer invading beyond the muscularis mucosae (≥T1a-MM) and then collated with the final pathologic diagnosis by an independent pathologist blinded to the clinical data.

RESULTS

The accuracy of invasion depth in WLI alone and WLI followed by ME-NBI was 71.4% and 65.3% (P=.375), respectively. Sensitivity for ≥T1a-MM was 61.1% for both groups (P=1.000), and specificity for ≥T1a-MM was 77.4% for WLI alone and 67.7% for WLI followed by ME-NBI (P=.375).

LIMITATION

Open-label trial.

CONCLUSIONS

ME-NBI showed no additional benefit to WLI for diagnosis of invasion depth of SESCC. (University Hospital Network Clinical Trials Registry number: UMIN000005632.).

Predicting the invasion depth of esophageal squamous cell carcinoma: comparison of endoscopic ultrasonography and magnifying endoscopy

OBJECTIVE

Predicting the invasion depth of superficial esophageal squamous cell carcinoma (SESCC) is important when selecting among therapeutic strategies. The aim of this study was to compare magnifying endoscopy with narrow-band imaging (ME-NBI) with endoscopic ultrasonography (EUS) for predicting the depth of tumor invasion in patients with SESCC.

METHODS

This study enrolled 51 patients with SESCC (52 SESCC lesions) who underwent both ME-NBI and EUS at Pusan National University Hospital during 2010-2013. We reviewed the patients' medical records and compared ME-NBI and EUS findings with histopathological results according to clinicopathological factors.

RESULTS

A total of 46 lesions in 45 patients were included in the final analysis. ME-NBI and EUS had overall accuracies of 76.1% and 84.8%, respectively, in distinguishing mucosal from non-mucosal cancers. There were no differences between ME-NBI and EUS in terms of sensitivities and specificities in distinguishing mucosal from non-mucosal cancers (p = 0.500 and p = 0.688, respectively). When both ME-NBI and EUS suggested a mucosal depth of lesion invasion, the frequency of mucosal cancer in the final histopathology was 94%. However, if either ME-NBI or EUS suggested a non-mucosal depth of invasion, the frequency of mucosal cancer was only 21%.

CONCLUSION

ME-NBI and EUS are accurate predictors of SESCC invasion depth. If both methods suggest a mucosal depth of lesion invasion, the accuracy of the prediction is increased. Therefore, when possible, it would be better to evaluate the invasion depth of SESCC using both ME-NBI and EUS before deciding to perform endoscopic resection.