Morphometry for microvessels in early gastric cancer by narrow band imaging-equipped magnifying endoscopy

Utility of linked color imaging for endoscopic diagnosis of early gastric cancer

BACKGROUND

Linked color imaging (LCI) is a method of endoscopic imaging that emphasizes slight differences in red mucosal color.

AIM

To evaluate LCI in diagnostic endoscopy of early gastric cancer and to compare LCI and pathological findings.

METHODS

Endoscopic images were obtained for 39 patients (43 lesions) with early gastric cancer. Three endoscopists evaluated lesion recognition with white light imaging (WLI) and LCI. Color values in Commission Internationale de l'Eclairage (CIE) 1976 L*a*b* color space were used to calculate the color difference (ΔE) between cancer lesions and non-cancer areas. After endoscopic submucosal dissection, blood vessel density in the surface layer of the gastric epithelium was evaluated pathologically. The identical region of interest was selected for analyses of endoscopic images (WLI and LCI) and pathological analyses.

RESULTS

LCI was superior for lesion recognition (P < 0.0001), and ΔE between cancer and non-cancer areas was significantly greater with LCI than WLI (29.4 vs 18.6, P < 0.0001). Blood vessel density was significantly higher in cancer lesions (5.96% vs 4.15%, P = 0.0004). An a* cut-off of ≥ 24 in CIE 1976 L*a*b* color space identified a cancer lesion using LCI with sensitivity of 76.7%, specificity of 93.0%, and accuracy of 84.9%.

CONCLUSION

LCI is more effective for recognition of early gastric cancer compared to WLI as a result of improved visualization of changes in redness. Surface blood vessel density was significantly higher in cancer lesions, and this result is consistent with LCI image analysis.

Histological verification of the usefulness of magnifying endoscopy with narrow-band imaging for horizontal margin diagnosis of differentiated-type early gastric cancers

BACKGROUND

Although magnifying endoscopy with narrow-band imaging (ME-NBI) can help identify the horizontal margin (HM) of early gastric cancer (EGC), little is known about the factors that can clarify the HM by using ME-NBI. We aimed to characterize the pathological features of lesions in which the HM was identified using ME-NBI.

METHODS

The HMs of 639 differentiated-type EGCs treated with endoscopic submucosal dissection or surgery were analyzed using conventional endoscopy and ME-NBI. The number and width of the intervening parts (IP) and the number, width, and depth of the subepithelial capillaries (SEC) in cancerous and noncancerous areas were measured.

RESULTS

In 13 lesions (2.0%), more than 90% of the HM was not recognized with conventional endoscopy, but 11 of these lesions were detectable with ME-NBI (NBI group). The HMs of the other 626 lesions were mostly recognized using conventional endoscopy (WLI/CE group). In the NBI group, the IP width, standard deviation (SD), and number of IPs did not significantly differ between the cancerous and noncancerous areas. However, the SEC number was significantly larger and the depth was shallower in cancerous areas. In the WLI/CE group, the IP width and SD were significantly larger, but the IP number was significantly smaller in cancerous areas. The SEC depth was significantly shallower in cancerous areas.

CONCLUSIONS

Differences of IP width, SD, and IP number may be factors for identifying HMs with conventional endoscopy. Because NBI can better visualize vessel structures, the increased SEC number and shallow SECs may clarify the HM.

Findings of the margin around lesions by magnifying endoscopy with narrow-band imaging in early gastric carcinoma and intestinal metaplasia

OBJECTIVE

Many endoscopists have reported their own classifications of early gastric carcinoma (EGC) using magnifying narrow-band imaging (M-NBI). However, few reports on classifying the margin around lesions by M-NBI have been published. The aim of this study was to advocate the usefulness of the demarcation area classification for the diagnosis of EGC.

METHODS

Altogether 197 lesions that could be investigated by M-NBI were included in this study, consisting of 115 EGC and 82 intestinal metaplasias (IM). We hypothesized that the changes in white zone (fusion and erasure signs) and blood vessel (extend and draw sign) were the indications of EGC and we retrospectively investigated this hypothesis.

RESULTS

For the investigation of the white zone in the demarcation area, both fusion (P < 0.0001) and erasure signs (P < 0.0001) were observed more often in EGC than in IM, with an accuracy of 80.7%. For the investigation of blood vessel in the demarcation area, both the extend (P < 0.001) and the draw sign (P < 0.0001) were observed more often in EGC than in IM, with an accuracy of 59.9%.

CONCLUSION

Estimations of the white zone and blood vessels in the demarcation area are useful for the diagnosis of EGC.

Magnifying endoscopy simple diagnostic algorithm for early gastric cancer (MESDA-G)

Gastric cancer is the third leading cause of cancer death worldwide. Early detection and accurate diagnosis of mucosal cancer is desirable in order to achieve decreased mortality; cause-specific survival of patients with early gastric cancer is reported to exceed 95%. Endoscopy is the functional modality to detect early cancer; however, the procedure is not definitive when using conventional white-light imaging. In contrast, magnifying narrow-band imaging (M-NBI), a novel endoscopic technology, is a powerful tool for characterizing gastric mucosal lesions because it can visualize the microvascular architecture and microsurface structure. To date, many reports on the diagnosis of early gastric cancer by M-NBI, including multicenter prospective randomized studies conducted in Japan, have been published in peer-reviewed international journals. Based on these published data, we devised a proposal for a diagnostic strategy for gastric mucosal cancer using M-NBI to simplify the process of diagnosis and improve accuracy. Herein, we recommend a diagnostic algorithm for early gastric cancer using magnifying endoscopy.

The clinical diagnostic value of target biopsy using narrow-band imaging endoscopy and accurate laryngeal carcinoma pathologic specimen acquisition

OBJECTIVE

To estimate the clinical significance of target biopsy for clinical diagnosis and determine accurate laryngeal lesion pathologic specimen acquisition via narrow-band imaging (NBI) endoscopy.

METHODS

A total of 138 samples from patients with laryngeal lesions (carcinoma, 118; hyperplasia, 3; mild dysplasia, 2; moderate dysplasia, 5; severe dysplasia, 5; vocal cord polyp, 1; and inflammatory lesion, 4) were collected from the Department of Otolaryngology Head and Neck Surgery of Tianjin Union Medical Center from 1 January 2013 to 1 February 2015. All patients were divided into the regular biopsy and NBI target biopsy groups; the imaging data were recorded and patient samples were biopsied. Pathologic diagnoses were used to evaluate the accuracies of regular and target biopsy.

RESULTS

Based on the pathologic diagnosis, NBI target pathology yielded an accurate laryngeal lesion pathologic specimen acquisition rate of 95.6% (65/68), significantly higher than that yielded by regular biopsy (75.7%, 53/70; χ² = 10.99, P = 0.001). In the NBI target pathology group, the correct accurate pathologic specimen acquisition rates at laryngeal cancer diagnostic stages 0 (Tis), I and II were 100%, 100% and 85.71%, respectively, which were higher than the corresponding rates in the regular biopsy group (0%, χ² = 10.000, P = 0.002; 25%, χ² = 5.625, P = 0.018; and 38.46%, χ² = 6.454, P = 0.011, respectively).

CONCLUSIONS

In cases of laryngeal carcinoma, NBI endoscopy plays an important role in clinical diagnosis and accurate pathologic specimen acquisition and could be a regular clinical method for laryngeal lesion detection.

Systematic review of the diagnosis of gastric premalignant conditions and neoplasia with high-resolution endoscopic technologies

AIM. The aim of the article is to systematically review the current evidence on the diagnostic use of narrow band imaging (NBI), flexible spectral imaging color enhancement (FICE) and endoscopic image enhancement technology i-scan endoscopies for gastric precancerous and cancerous lesions. MATERIALS AND METHODS. Original manuscripts were searched in PubMed until October 2012. Pertinent data were collected and pooled diagnostic accuracy measures were estimated when possible. RESULTs. In total, 38 studies were evaluated. Thirty-one studies were included for NBI and 7 studies for FICE assessment in this systematic review. No article was found meeting inclusion criteria for i-scan endoscopy. The most defined and evaluated outcomes were cancer-related (n = 26). Quality Assessment of Diagnostic Accuracy Studies score varied from 9 to 12 (out of 14). Only few studies assessed the interobserver reliability. On a patient level analysis, NBI's pooled sensitivity, specificity and diagnostic odds ratio were 0.67 (95% CI: 0.61-0.73), 0.81 (95% CI: 0.76-0.85) and 22.71 (95% CI: 12.53-41.1), respectively for diagnosing normal mucosa; 0.86 (95% CI: 0.82-0.90), 0.77 (95% CI: 0.73-0.80) and 17.01 (95% CI: 1.4-207.2) for intestinal metaplasia and 0.90 (95% CI: 0.84-0.94), 0.83 (95% CI: 0.80-0.86) and 47.61 (95% CI: 4.61-491.34) for dysplasia. Owing to the insufficient data and different definitions, we could not aggregate the results for FICE. CONCLUSION. Gastric pattern descriptions have been proposed for NBI and FICE studies by gathering all descriptions in one single description. The classification systems varied between studies, a single description of gastric mucosal features with HR--scopes or at least per technology--will have to be agreed on.

Usefulness of the DL in ME with NBI for determining the expanded area of early-stage differentiated gastric carcinoma

AIM: To investigate whether magnifying endoscopy with narrow band imaging (ME-NBI) is useful for evaluating the area of superficial, depressed- or flat-type differentiated adenocarcinoma of the stomach.

METHODS: This procedure was performed in Saitama Medical University International Medical Center, Japanese Red Cross Kumamoto Hospital and Kitakyushu Municipal Medical Center. The subjects were 31 patients in whom biopsy findings, from superficial, depressed- or flat-type gastric lesion, suggested differentiated adenocarcinoma in the above 3 hospitals between January and December 2009. Biopsy was performed on the lesion and non-lesion sides of a boundary (imaginary boundary) visualized on ME-NBI. The results were pathologically investigated. We evaluated the accuracy of estimating a demarcation line (DL) on ME-NBI in comparison with biopsy findings as a gold standard.

RESULTS: The DL that could be recognized at 2 points on the orifice and anal sides of each lesion during ME-NBI was consistent with the pathological findings in 22 patients with 0-IIc lesions, 7 with 0-IIb lesions, and 2 with 0-IIb + IIc lesions, showing an accuracy of 100%.

CONCLUSION: The results suggest the usefulness of ME-NBI for evaluating the area of superficial, depressed- and flat-type differentiated adenocarcinoma of the stomach.