Diagnosis of early gastric cancer using narrow band imaging and acetic acid.

AIM: To determine whether the endoscopic findings of depressed-type early gastric cancers (EGCs) could precisely predict the histological type. METHODS: Ninety depressed-type EGCs in 72 patients were macroscopically and histologically identified. We evaluated the microvascular (MV) and mucosal surface (MS) patterns of depressed-type EGCs using magnifying endoscopy (ME) with narrow-band imaging (NBI) (NBI-ME) and ME enhanced by 1.5% acetic acid, respectively. First, depressed-type EGCs were classified according to MV pattern by NBI-ME. Subsequently, EGCs unclassified by MV pattern were classified according to MS pattern by enhanced ME (EME) images obtained from the same angle. RESULTS: We classified the depressed-type EGCs into the following 2 MV patterns using NBI-ME: a fine-network pattern that indicated differentiated adenocarcinoma (25/25, 100%) and a corkscrew pattern that likely indicated undifferentiated adenocarcinoma (18/23, 78.3%). However, 42 of the 90 (46.7%) lesions could not be classified into MV patterns by NBI-ME. These unclassified lesions were then evaluated for MS patterns using EME, which classified 33 (81.0%) lesions as MS patterns, diagnosed as differentiated adenocarcinoma. As a result, 76 of the 90 (84.4%) lesions were matched with histological diagnoses using a combination of NBI-ME and EME. CONCLUSION: A combination of NBI-ME and EME was useful in predicting the histological type of depressed-type EGC.

Clinical characteristics and management of gastric tube cancer with endoscopic submucosal dissection.

AIM: To identify the characteristics of gastric tube cancer (GTC) and the complications associated with endoscopic submucosal dissection (ESD) for GTC. METHODS: Between 2007 and 2012, 11 individuals with early gastric cancer in the reconstructed gastric tube after esophagectomy who underwent ESD in this hospital were studied. The characteristics of GTC were identified, and the complications of ESD for GTC were analyzed at three phases: preoperative, intraoperative, and postoperative. RESULTS: A total of 11 consecutive patients with 11 GTCs were selected for this study. All cases underwent en bloc resections by ESD. The median procedure time was 142 min. The average GTC diameter was 26.1 mm, and the average size of the resected lesions was 45.5 mm. The histopathological diagnosis in all cases was a differentiated adenocarcinoma. In the preoperative phase, anastomotic strictures (5/11, 45%) and food residues (4/11, 36.4%) in the gastric tube were the main complications. In the intraoperative phase, bleeding was observed in 5 cases (45%). The postoperative complications observed were delayed bleeding in 2 cases (18.2%) and stenosis in one case (9.1%). The case with stenosis was successfully treated using endoscopic balloon dilatation. CONCLUSION: Minor complications were frequently observed. However, all GTCs underwent en bloc resection with ESD without any serious complications. ESD is considered a useful treatment for GTC.

Usefulness of magnifying endoscopy with narrow-band imaging for diagnosis of depressed gastric lesions.

The usefulness of magnifying endoscopy with narrow-band imaging (ME-NBI) for the diagnosis of early gastric cancer is well known, however, there are no evaluation criteria. The aim of this study was to devise and evaluate a novel diagnostic algorithm for ME-NBI in depressed early gastric cancer. Between August, 2007 and May, 2011, 90 patients with a total of 110 depressed gastric lesions were enrolled in the study. A diagnostic algorithm was devised based on ME-NBI microvascular findings: microvascular irregularity and abnormal microvascular patterns (fine network, corkscrew and unclassified patterns). The diagnostic efficiency of the algorithm for gastric cancer and histological grade was assessed by measuring its mean sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy. Furthermore, inter- and intra-observer variation were measured. In the differential diagnosis of gastric cancer from non-cancerous lesions, the mean sensitivity, specificity, PPV, NPV, and accuracy of the diagnostic algorithm were 86.7, 48.0, 94.4, 26.7, and 83.2%, respectively. Furthermore, in the differential diagnosis of undifferentiated adenocarcinoma from differentiated adenocarcinoma, the mean sensitivity, specificity, PPV, NPV, and accuracy of the diagnostic algorithm were 61.6, 86.3, 69.0, 84.8, and 79.1%, respectively. For the ME-NBI final diagnosis using this algorithm, the mean κ values for inter- and intra-observer agreement were 0.50 and 0.77, respectively. In conclusion, the diagnostic algorithm based on ME-NBI microvascular findings was convenient and had high diagnostic accuracy, reliability and reproducibility in the differential diagnosis of depressed gastric lesions.

Quantitative analysis of colorectal mucosal lesions by autofluorescence endoscopy: discrimination of carcinomas from other lesions.

A newly developed autofluorescence (AF) imaging technique was applied during colonoscopy in a clinical setting. This pilot study was conducted to evaluate the clinical feasibility of applying AF endoscopy for distinguishing colorectal lesions. A total of 54 colorectal mucosal lesions obtained from 43 patients who underwent both white-light and AF endoscopy and were treated by endoscopy or surgery were assessed. Of the lesions, 11 were hyperplastic polyps, 30 were adenomas and 13 were carcinomas. To quantify the AF intensity, a color-contrast index (CCI) was determined and evaluated in relation to the histology, size and shape of each lesion. CCI was significantly associated with the histology and size of the lesions, but not their shape. CCI increased as the malignant potential increased (in the order of hyperplastic polyps→adenomas→carcinomas), irrespective of the lesion size (r=0.797, p<0.0001 for size>8 mm; r=0.622, p=0.0045 for size>8 mm but >15 mm; r=0.644, p=0.0071 for size>15 mm). In each size group, CCI tended to be higher for carcinomas than for adenomas, and also higher for adenomas than for hyperplastic polyps. CCI allowed discrimination of adenomas/carcinomas from hyperplastic polyps with 95.3% sensitivity and 63.6% specificity (cut-off value, 14.5), and of colorectal carcinomas from adenomas with 84.6% sensitivity and 80.0% specificity (cut-off value, 28.0). These results suggest that the quantitative analysis of AF intensity using CCI is helpful to discriminate among different types of colorectal mucosal lesions, including carcinomas.

Endoscopic discrimination of sessile serrated adenomas from other serrated lesions.

Sessile serrated adenoma (SSA) is a proposed precursor of colorectal carcinogenesis. This study aimed to analyze the potential of endoscopy to discriminate SSA from other serrated lesions, specifically traditional serrated adenoma (TSA) and hyperplastic polyp (HP). Of 145 serrated lesions, 111 sessile serrated lesions including 32 TSAs, 25 SSAs and 54 HPs were analyzed for size, color, location and morphologic features using conventional endoscopy and magnifying chromoendoscopy. SSA was preferentially located in the right colon, whereas TSA and HP were located in the left colon. The sizes of SSA and TSA were larger than those of HP. The lesion color was indistinguishable among TSA, SSA and HP. Macroscopically, a pinecone-like or two-tier raised appearance were found more frequently in TSA than in SAA and HP. Under magnified chromoendoscopic observation, the stellar III(L) pit pattern and fern-like appearance were observed more frequently in TSA than in SAA and HP. In conclusion, endoscopic discrimination between SSA and other sessile serrated lesions based on morphological features was difficult. However, size and location of the lesions facilitated diagnosis.

Microvascular invasion in patients with hepatocellular carcinoma and its predictable clinicopathological factors.

BACKGROUND: Macroscopic vascular invasion is known to be a poor prognostic factor in hepatocellular carcinoma (HCC). The aim of this study was to determine the outcomes and predictive factors after hepatic resection for HCC with microvascular invasion (MVI). METHODS: One hundred ten patients who underwent curative resection for HCC without macroscopic vascular invasion were included in this retrospective study. The risk factors of these patients for recurrence-free and disease-specific survival were investigated, and the clinicopathological factors predicting the presence of MVI were also determined. RESULTS: Of the 110 resected specimens, 49 (45%) had evidence of MVI. By univariate analysis, MVI was found to be statistically significantly associated with greater tumor size, gross classification, histological grade, and intrahepatic micrometastasis. Gross classification proved to be the only independent predictive factor for MVI by multiple logistic regression analysis. By multivariate analysis, cirrhosis and MVI were identified as independent risk factors for recurrence-free survival. The 5-year recurrence-free survival rates for patients with and without MVI were 20.8% and 52.6%, respectively. By multivariate analysis, the number of tumors, presence of MVI, and intrahepatic micrometastasis were identified as independent predictors of disease-specific survival. The 5-year disease-specific survival rates for patients with and without MVI were 59.3% and 92.0%, respectively. CONCLUSIONS: The presence of MVI was the most important risk factor affecting recurrence and survival in HCC patients after curative resection. Furthermore, this study showed that gross classification of HCC can be very helpful in predicting the presence of MVI.