Use of endocytoscopy for identification of sessile serrated adenoma/polyps and hyperplastic polyps by quantitative image analysis of the luminal areas.

BACKGROUND AND STUDY AIMS: Recent studies that used magnifying chromoendoscopy and endocytoscopy (EC) to investigate endoscopic features of sessile serrated adenoma/polyps (SSA/Ps) suggested that a dilated crypt opening was an important indicator of SSA/Ps. However, no studies to date have measured the actual extent of dilatation. Hence, we investigated retrospectively the luminal areas using EC to determine a cutoff value for differentiating SSA/Ps from hyperplastic polyps (HPs). PATIENTS AND METHODS: A total of 101 lesions, including 25 SSA/Ps, 66 HPs, and 10 normal mucosal samples, assessed by an integrated-type EC were collected. For each lesion, 1 image that showed the widest lumen was selected and the average area of the contiguous 3 lumens were calculated. The cutoff value differentiating SSAPs from HPs was determined by receiver operating curve (ROC) analysis. RESULTS: The mean luminal areas of SSA/Ps and HPs were 4152 µm 2 and 2117 µm 2 , respectively. ROC analysis found that a luminal area cutoff of 3068 µm 2 had a sensitivity of 80.0 %, a specificity of 77.3 %, an accuracy of 78.0 %, and an area under the ROC curve of 0.865. Furthermore, a cutoff of ≥ 556 µm 2 was found to accurately distinguish between HPs and normal mucosa (sensitivity 98.5 %, specificity 100 %, accuracy 98.7 %, and AUC 0.998). CONCLUSIONS: EC analysis of the luminal area is useful for differentiating between SSAPs and HPs. This approach could be adapted for computer-aided diagnosis of SSA/P.

Electrolyte depletion syndrome (McKittrick-Wheelock syndrome) successfully treated by endoscopic submucosal dissection.

A 66-year-old woman presented to us with malaise, anorexia and rectal mucous discharge, and her laboratory data showed severe hyponatremia, hypokalemia, hypochloremia and renal failure. Computed tomography revealed massive occupation of the rectum by a large tumor. Colonoscopy revealed a mucus-rich villous tumor in the rectum. As there were no other factors that could cause an electrolyte disorder, she was diagnosed with McKittrick-Wheelock syndrome (MWS). The current standard treatment for MWS is partial surgical colectomy. However, surgeries are invasive and postoperative complications sometimes become an issue. After confirming no signs of submucosal invasion of the tumor by magnifying chromoendoscopic examination, endoscopic submucosal dissection (ESD) was indicated. The tumor was completely removed en bloc without adverse events. The histology showed a mucosal adenocarcinoma containing a villous component, 24.5 x 17.0 cm in size. This removal dramatically improved the patient's symptoms and the electrolyte abnormalities without medication. Although several sessions of endoscopic balloon dilation were required to treat postoperative stricture, she has been symptom-free and had no recurrence for 4 years after treatment. We experienced a case of MWS treated by ESD instead of surgery. ESD should be feasible and beneficial for the treatment of MWS.

Efficiency of endocytoscopy in differentiating types of serrated polyps.

BACKGROUND: Accurate endoscopic criteria are needed to differentiate serrated polyps, including hyperplastic polyp (HP), sessile serrated adenoma/polyp (SSA/P), and traditional serrated adenoma (TSA), because some are precursors of colorectal cancers. OBJECTIVE: To determine the endocytoscopic features of each type of serrated polyp, especially the shapes of lumens and nuclei. DESIGN: Retrospective study. SETTING: Single, tertiary-care referral center. PATIENTS: Patients who underwent removal of serrated polyps from May 2005 to December 2012. INTERVENTION: Endocytoscopy was performed. Endocytoscopic images were evaluated by assessing the shapes of the lumens and nuclei of the target lesions. MAIN OUTCOME MEASUREMENTS: The significant endocytoscopic features in differentiating among types of serrated polyps. RESULTS: Of the 58 eligible lesions, 27 were classified as HP, 12 as SSA/P, and 19 as TSA. Most HPs (77.8%) had star-like lumens, and most SSA/Ps (83.3%) had oval lumens. The lumens of TSAs were serrated (31.6%) or villous (68.4%), with both shapes seen only in TSAs. Most HPs (92.6%) and SSA/Ps (75.0%) had small, round nuclei, and all TSAs had fusiform nuclei. Features significantly differentiating TSAs from HPs and SSA/Ps were the presence of fusiform nuclei (P < .001) and villous (P < .001) and serrated (P = .002) lumens. The presence of oval lumens was significantly characteristic of SSA/Ps (P < .001), and the presence of star-like lumens was significantly characteristic of HPs (P < .001). LIMITATIONS: Retrospective design. Single-center study. CONCLUSION: The shape of lumens and nuclei on endocytoscopy can efficiently differentiate among the different types of serrated polyps. ( CLINICAL TRIAL REGISTRATION NUMBER: UMIN Clinical Trials Registry UMIN000007850.).

Double staining with crystal violet and methylene blue is appropriate for colonic endocytoscopy: an in vivo prospective pilot study.

BACKGROUND AND AIM: Endocytoscopy (EC) at ultra-high magnification enables in vivo visualization of cellular atypia of gastrointestinal mucosae. Clear images are essential for precise diagnosis by EC. The aim of the present study was to evaluate the optimal staining method for EC in the colon. METHODS: Thirty prospectively enrolled patients were allocated 1:1:1 to three distinct staining methods: 0.05% crystal violet (CV) alone, 1% methylene blue (MB) alone, or CV+MB (CM double). Normal rectal mucosae were stained with each dye and videos of EC images were recorded. Visibility of nuclei and gland formation after staining were evaluated as 'recognizable' or 'not recognizable'. Time for each parameter to become 'recognizable' was measured, and the average times for the three staining regimens were compared. RESULTS: MB alone and CM double staining resulted in 'recognizable' (102 ± 27 vs 89 ± 22 s, P=0.263) nuclei within comparable periods of time, whereas CV alone was unable to identify nuclei. Gland formation became 'recognizable' sooner after CM double staining than after MB alone (61 ± 16 vs 108 ± 24 s, P<0.001). CONCLUSIONS: Double staining with CV and MB, which rapidly provided recognizable images of both nuclei and gland formation, is an appropriate staining regimen for colonic EC.

Endocytoscopy can provide additional diagnostic ability to magnifying chromoendoscopy for colorectal neoplasms.

BACKGROUND AND AIM: Pit pattern (PIT) diagnosis with magnifying chromoendoscopy is effective diagnostic method for predicting a massively invasive submucosal colorectal cancer (SMm) which has possibility of metastasis, whereas endocytoscopy (EC) is recently reported to provide excellent diagnostic ability by enabling in vivo cellular visualization. The aim was to assess the additional diagnostic value of EC to PIT for diagnosing colorectal lesions. METHODS: We conducted a retrospective comparative analysis using a prospectively recorded database in a referral hospital. The subjects were 538 patients who were detected of a colorectal lesion with use of a magnifying colonoscope with EC capability. Each detected lesion was initially diagnosed by PIT findings followed by EC diagnosis by the on-site endoscopist. The diagnostic abilities in predicting neoplastic change and SMm were compared between PIT and PIT plus EC. RESULTS: Overall, 514 lesions from 455 patients were available for analysis. Of them, there were 58 non-neoplastic lesions, 352 adenomas, 15 slightly invasive submucosal cancers, and 89 SMm. The diagnostic abilities of predicting neoplastic change were comparable between PIT and PIT plus EC: sensitivity was 97.8% versus 97.4%, specificity was 91.4% versus 89.7%, and accuracy was 97.1% versus 96.5%. Regarding those of predicting SMm, PIT plus EC showed additional specificity and accuracy to PIT: specificity was 99.1% versus 97.6% (P = 0.041), and accuracy was 96.3% versus 93.8% (P = 0.004). CONCLUSIONS: Though PIT has feasible diagnostic ability for predicting both neoplastic change and SMm, EC provides additional diagnostic value to PIT diagnosis for predicting SMm.

Endoscopic submucosal dissection for early gastric cancer in anastomosis site after distal gastrectomy.

BACKGROUND: Detection of early gastric cancer (EGC) in the remnant stomach is increasing because of follow-up endoscopic surveillance programs. Endoscopic treatment appears to be desirable for EGC in the remnant stomach because it is less invasive than surgical resection. METHODS: In this retrospective study, to evaluate the feasibility of endoscopic submucosal dissection (ESD) for EGC in an anastomotic site, treatment results of ESD for EGC in an anastomotic site and in remnant stomach not involving an anastomotic site were compared. In total, 11 EGC lesions of anastomotic sites in 11 patients and 22 EGC lesions of remnant stomach not involving an anastomotic site in 21 patients were treated by ESD. RESULTS: All lesions were successfully treated by en bloc resection. There were three patients with perforations in the anastomotic site group. Although resected specimen size and tumor size were larger in the anastomotic site group than in the non-anastomotic site group (P < 0.01), the procedure duration was far longer in the anastomotic site group than in the non-anastomotic site group (P < 0.01). The speed of the procedure was faster in the non-anastomotic site group than in the anastomotic site group (P < 0.05). CONCLUSIONS: Although ESD for EGC in an anastomotic site is a time-consuming procedure and requires advanced techniques compared with ESD for EGC not involving an anastomotic site, a high en bloc resection rate was achieved. ESD by endoscopists with sufficient experience appears to be a feasible treatment for EGC in an anastomotic site.

[Whipple's disease].

A 36-year-old woman presented with fever, diarrhea, and weight loss in April 2011. Upper GI endoscopy and colonoscopy showed a diffuse yellow-white shaggy mucosa in the second part of the duodenum and the ileum end, respectively. These lesions in these 2 locations were biopsied, and both specimens showed distended epithelial villi and massive infiltration of foamy macrophages in the lamina propria. PCR was performed to identify causative bacilli. DNA extracted from the duodenal mucosa showed a specific PCR product, confirming the diagnosis of Whipple's disease. The patient was treated with a 2-week course of ceftriaxone, followed by sulfamethoxazole/trimethoprim. After we started the treatment, the patient developed complications of infective endocarditis and meningitis. The patient was relieved of her symptoms using a combination of gentamicin, penicillin G, ampicillin, meropenem, and vancomycin.

Endoscopic characteristics of colorectal serrated lesions.

BACKGROUND/AIMS: With the recent changes of pathological concepts, colorectal serrated lesions can be now divided into traditional serrated adenoma, typical hyperplastic polyp and sessile serrated polyp. The aim of this study is to clarify the endoscopic differences among these three groups. METHODOLOGY: A total number of 362 serrated lesions larger than 5mm were evaluated. These were detected with ordinary view and observed also with magnifying chromoendoscopic view. The final pathologic diagnosis of the resected specimens was made blinded. RESULTS: There were significant differences between traditional serrated adenoma and sessile serrated polypconcerning location, configuration and color. In chromoendoscopy, most of sessile serrated polyps and typical hyperplastic polyps showed star-like pattern, in contrast with traditional serrated adenomas most of which had fernor pinecone-like pattern. The differential diagnosis between traditional sessile polyp and the other two was possible with high accuracy. On the other hand, endoscopic distinction between sessile serrated polyp and typical hyperplastic polyp was not easy, except that the location and size were significantly different. CONCLUSIONS: We can endoscopically differentiate between traditional serrated adenoma and sessile serrated polyp or typical hyperplastic polyp, but it is difficult to differentiate between the latter two.

Clinical usefulness of pit patterns for detecting colonic lesions requiring surgical treatment.

BACKGROUND: The number of patients suffering from colorectal cancer is increasing. According to Japanese guidelines, lesions with a submucosal invasive depth >1,000 µm should be treated with radical proctocolectomy. We propose and evaluate a new clinical classification for pit patterns that uses endoscopy to assess lesion depth for determination of the appropriate therapeutic approach for early colorectal cancers and adenomas. METHODS: Endoscopic images of colorectal adenomas and early cancer cases with type V(I) pit pattern, resected surgically or endoscopically from April 2002 to April 2007 at Showa University Yokohama Northern Hospital, were utilized for analysis. Each image was retrospectively analyzed for (A) pit narrowness, (B) irregular pit margins, and (C) indistinct stromal staining. Sensitivity, specificity, and predictive value were evaluated as major outcomes, using pathological results as the standard. RESULT: In total, 186 cases were assessed. With all features considered (A, B, and C), the sensitivity, specificity, and positive and negative predictive values were 47.8%, 86.3%, 66.0%, and 74.2%, respectively. When limited to two features (A and B), these values were 75.3%, 81.2%, 70.2%, and 84.8%, respectively. CONCLUSION: Our results suggest that the established criteria can, to a certain degree, distinguish between high and low irregularity in colorectal lesions with V(I) pit pattern indicating submucosal cancer infiltration of more or less than 1,000 µm with the clinical consequence of surgery versus endoscopic mucosal resection/endoscopic mucosal dissection.

Vascular pattern classification of colorectal lesions with narrow band imaging magnifying endoscopy.

Magnifying narrow band imaging (NBI) has enabled to observe the vascular pattern of colorectal lesions. Their broad findings have been divided into six groups according to endoscopical vascular features: normal, faint, network, dense, irregular and sparse. Most hyperplastic polyps show a faint pattern. The vascular patterns of adenomas are mainly network or dense ones. The predominant vascular patterns of cancer were irregular and sparse. Indeed, irregular pattern has found to be characteristic for protruded or flat-elevated cancer, whereas sparse pattern unique for depressed cancer. Through NBI, neoplastic lesions could be differentiated from those non-neoplastic with sensitivity of 83.5%, specificity of 98.7% and accuracy of 98.2%. It was able to distinguish between massively submucosal invasive cancers and slightly submucosal invasive cancers by using the vascular pattern with 91.0% sensitivity and 79.4% specificity. The overall accuracy was 88.3%. NBI system has showed to be a valuable technique for distinguishing neoplastic from non-neoplastic lesions, as well as massively from slightly submucosal invasive cancer. Therefore, vascular pattern analysis might be a promising tool for determining treatment selection, whether endoscopical or surgically.

[Present state and foresight of endoscopic therapy].

The advent of magnifying chromoendoscopy has enabled endoscopists to observe the mucosal structures in great detail for precise diagnosis; the pit patterns, irregular vascular patterns with narrow band imaging(NBI), and intra-epithelial papillary capillary loop (IPCL) pattern. The achievement of high resolution images has also improved accuracy of diagnosis for neoplasm in gastroenterology. Endocytoscopy is developed from magnifying chromoendoscopy, and is now under clinical investigation for use. Many of early gastrointestinal carcinoma has been treated endoscopically, and ESD (endoscopic submucosal dissection) technique, resection of the neoplasm en bloc, has disseminated recent years. The indication for ESD will be broadened in the near future, and the precise diagnosis for the neoplasm is essential, not to loose the interest of patients.

Diagnostic accuracy of pit pattern and vascular pattern analyses in colorectal lesions.

BACKGROUND: The aim of this prospective study is to compare the usefulness of magnifying narrow band imaging (NBI) and magnifying chromoendoscopy in the diagnosis of colorectal lesions. METHODS: The subjects were 1185 patients who underwent a complete colonoscopic examination and endoscopic or surgical treatment, from January 2006 to February 2008. A total of 1473 lesions were evaluated (53 hyperplastic polyps, 1317 adenomas, 103 submucosally invasive cancers). The digital images with NBI or chromoendoscopy were recorded and diagnosed independently from each other by two endoscopists who were blinded to the final pathological diagnosis. RESULTS: We could differentiate between neoplastic and non-neoplastic lesions with sensitivity of 88.9%, specificity of 98.5% and accuracy of 98.2% according to the vascular pattern. By recognizing an irregular or sparse pattern with NBI, massively invasive submucosal cancer could be diagnosed with the sensitivity and specificity of 94.9% and 76.0%. Using chromoendoscopy, we could differentiate between neoplastic and non-neoplastic lesions with sensitivity of 86.8% and specificity of 99.2%. We were able to differentiate between massively invasive cancers and slightly invasive cancers using the pit patterns with sensitivity of 89.7% and specificity of 88.0%. The specificity was superior to that of NBI colonoscopy. CONCLUSION: Both NBI and chromoendoscopy can be useful for distinguishing between neoplastic and non-neoplastic lesions. In the diagnosis of submucosal cancer, pit pattern diagnosis was slightly superior to vascular pattern diagnosis. It is desirable to perform chromoendoscopy in addition to NBI for distinguishing between slightly and massively invasive submucosal cancer lesions and determining the treatment.

Diagnosis of colorectal lesions with the magnifying narrow-band imaging system.

BACKGROUND: Narrow-band imaging (NBI) emphasizes the surface microvasculature of the GI tract and may help in detecting small neoplasms. OBJECTIVE: The aim of this study was to clarify the value of the NBI system in tissue characterization and differential diagnosis. DESIGN: A prospective study. SETTING: Digestive Disease Center of Showa University Northern Yokohama Hospital. PATIENTS: The subjects were 495 patients who, from January 2006 to June 2007, underwent a complete colonoscopic examination. A total of 617 lesions were evaluated in the 495 patients (33 hyperplastic polyps, 532 adenomas, 52 submucosally invasive [T1] cancers). RESULTS: Most hyperplastic polyps showed a faint pattern. The vascular patterns of adenomas were mainly the network pattern or the dense pattern. The major vascular patterns of cancers were the irregular pattern and the sparse pattern. The irregular pattern was characteristic for protruded or flat-elevated cancers, whereas the sparse pattern was unique for depressed cancers. When we assumed that the faint pattern was diagnostic for hyperplastic polyps, we could differentiate between neoplastic and non-neoplastic lesions with a sensitivity of 90.9% and a specificity of 97.1%. Likewise, irregular and sparse patterns were assumed to be indices of massively invasive submucosal cancer, the sensitivity was 100%, the specificity was 95.8%, and the accuracy rate was 96.1%. LIMITATIONS: This study was performed at a single center. CONCLUSIONS: The NBI system was valuable for distinguishing between neoplastic and non-neoplastic lesions, as well as between cancers and adenomas. Vascular pattern analysis can also be a promising tool for determining treatment selection, either endoscopy or surgery.

Role of metallothionein in Helicobacter pylori-positive gastric mucosa with or without early gastric cancer and the effect on its expression after eradication therapy.

BACKGROUND AND AIM: Metallothionein (MT) has a proven relationship with various kinds of cancer and reduces tissue damage. Helicobacter pylori (H. pylori) infection is associated with the alteration of gastric epithelial cell cycle events, a condition implicated in the initiation and development of gastric cancer. This study investigates the role of MT in H. pylori-induced gastritis with or without early gastric cancer (ECG) and evaluates the effect on MT expression after eradication therapy. METHODS: Gastric biopsy samples were immunohistochemically examined for MT expression in 36 H. pylori-negative patients without ECG and 98 positive patients with or without ECG. Real time polymerase chain reaction was performed in 14 antral biopsy samples with or without H. pylori. The severity of gastritis was also evaluated according to the updated Sydney System. In 31 successfully eradicated patients, the above assessment was repeated for two consecutive years. RESULTS: MT expression was higher in H. pylori-negative patients than in positive patients (P < 0.01). Moreover, in the corpus it was higher in H. pylori-positive patients without ECG compared to those with ECG (P < 0.05). The MT labeling index had a negative correlation with the severity of gastritis (P < 0.01). A positive correlation was shown between the MT labeling index and apoptosis: proliferation ratio (r = 0.41, P < 0.01). The MT labeling index in H. pylori-positive patients was gradually recovered after eradication (P < 0.05). CONCLUSION: The decrease of MT expression cannot prevent tissue damage in H. pylori-positive gastric mucosa and leads to more severe gastritis. This phenomenon may be attributed to gastric carcinogenesis. H. pylori eradication increases MT expression and may reduce the risk of ECG.

Relationship of BRAF mutation, morphology, and apoptosis in early colorectal cancer.

BACKGROUND AND AIMS: Many investigators have reported flat and depressed lesions as a new type of precursor of colorectal cancer. In our previous study, we determined that mutations in the BRAF gene may contribute to colorectal carcinogenesis by inhibiting apoptosis. However, the relationship among BRAF mutations, morphology and apoptosis in early colorectal cancer has not been clear. Therefore, gene alternation, morphology, and apoptosis in early colorectal cancer were investigated. MATERIALS AND METHODS: Forty-five flat and depressed early colorectal cancer samples and 43 polypoid early colorectal cancer samples were analyzed. Mutations in the BRAF gene and the K-ras gene were examined by direct sequence analysis, and proliferative activity and induction of apoptosis were evaluated using immunohistochemical examination. RESULTS FINDINGS: BRAF mutations were found in 5 (11.1%) of 45 flat and depressed early colorectal cancer samples. No BRAF alteration was found in polypoid early colorectal cancer samples. Mutations in the K-ras gene were detected in 13 (30.2%) of 43 polypoid early colorectal cancer samples. The rate of submucosal invasion of the samples with BRAF mutations was significantly higher than that of the samples with K-ras mutations (p<0.05). INTERPRETATION/CONCLUSIONS: BRAF and K-ras mutations were independent factors that influenced morphology in early colorectal cancer. In this study, the relationship between BRAF mutation and apoptosis is not so clear, but BRAF mutations and inhibition in apoptosis may play an important role in the developmental process of flat and depressed early colorectal cancer.

BRAF mutation associated with dysregulation of apoptosis in human colorectal neoplasms.

To understand the role of BRAF dysfunction in the carcinogenesis and progression/development of colorectal tumors, the authors investigated genetic alterations in the BRAF gene in human colorectal neoplasms as well as the effects of an RAS inhibitor in BRAF-mutant cells. Seven colon cancer cell lines and 116 colorectal tumors (34 adenomas and 82 adenocarcinomas) were analyzed. Genetic alterations in the BRAF and K-ras genes were examined using polymerase chain reaction-single strand conformation polymorphism and direct sequencing analyses. The growth-inhibitory and apoptosis-inducing effects of the FTI-277 RAS inhibitor in colon cancer cell lines were analyzed as well. An immunohistochemical study was also performed to investigate the correlations between the clinicopathologic parameters involved in the Ki-67 labeling index and the number of apoptotic bodies in tumor cells. FTI-277 did not suppress the proliferation of BRAF-mutant cells (WiDr and TCO), but remarkably inhibited the growth of K-ras mutant cells (LoVo). Interestingly, LoVo cells underwent apoptosis by FTI-277 in a dose-dependent manner, whereas WiDr cells were resistant to this agent. In tumor samples, BRAF mutations were found in 1 (3.0%) of 33 adenomas and 6 (7.2%) of 83 adenocarcinomas. No tumor exhibited mutations in both the BRAF and K-ras genes. Neither BRAF nor K-ras mutations correlated with the Ki-67 labeling index immunohistochemically. However, the number of apoptotic bodies was significantly decreased in the BRAF-mutant tumors. Mutation in the BRAF gene may contribute to colorectal carcinogenesis by upregulating the antiapoptotic role of the RAS/RAF/MEK/ERK pathway.

BRAF/K-ras mutation, microsatellite instability, and promoter hypermethylation of hMLH1/MGMT in human gastric carcinomas.

BACKGROUND: The BRAF and K-ras genes are the most frequently mutated oncogenes in various human malignancies. We examined BRAF and K-ras mutations in human gastric cancer, and investigated their relationship with microsatellite instability (MSI) and the hypermethylation of promoter regions in hMLH1 and O6-methylguanine DNA methyltransferase (MGMT). METHODS: Sixteen gastric cancer cell lines and 62 gastric cancer tissue samples were screened for BRAF and K-ras mutations by direct sequencing. We also performed a microsatellite assay and investigated methylation status in the promoter regions of hMLH1 and MGMT. RESULTS: mutation was not found in any of the cancer cell lines examined. One (1.6%) cancer tissue sample showed a point mutation in the BRAF gene (GTG --> GAG; V599E). K-ras mutation (GGT --> GAT, G12D) was detected in five (31%) gastric cancer cell lines and in 1 (1.6%) gastric cancer tissue sample. In the gastric cancer tissue samples examined, MSI was detected in 23 (37%) samples. Hypermethylated promoter regions in hMLH1 and MGMT, respectively, were detected in 6 (10%) and 13 (21%) gastric cancer tissue samples. Microsatellite stable (MSS) tumors showed frequent lymphatic invasion (P = 0.050). CONCLUSION: Although BRAF mutation has been reported in a variety of other human cancers, it is a rare event in the carcinogenesis and progression/development of gastric cancer.