Wataru Sano

NBI and NBI Combined with Magnifying Colonoscopy

Although magnifying chromoendoscopy had been a reliable diagnostic tool, narrow-band imaging (NBI) has been developed in Japan since 1999 and has now replaced the major role of chromoendoscopy because of its convenience and simplicity. In this paper, we principally describe the efficacy of magnifying chromoendoscopy and magnifying colonoscopy with NBI for detection, histological prediction, estimation of the depth of early colorectal cancer, and future prospects. Although some meta-analyses have concluded that NBI is not superior to white light imaging for detection of adenomatous polyps in screening colonoscopy, NBI with magnification colonoscopy is useful for histological prediction, or for estimating the depth of invasion. To standardize these diagnostic strategies, we will focus on the NBI International Colorectal Endoscopic (NICE) classification proposed for use by endoscopists with or without a magnifying endoscope. However, more prospective research is needed to prove that this classification can be applied with satisfactory availability, feasibility, and reliability. In the future, NBI might contribute to the evaluation of real-time histological prediction during colonoscopy, which has substantial benefits for both reducing the risk of polypectomy and saving the cost of histological evaluation by resecting and discarding diminutive adenomatous polyps (resect and discard strategy).

Colorectal cancer screening of the general population in East Asia

In recent years, the incidence of colorectal cancer (CRC) has been increasing, and CRC has been becoming the major cause of cancer deaths in Asian countries. Therefore, an organized screening program to reduce CRC incidence and mortality is currently implemented in each country. In the present review, we summarize the current status and future perspectives of CRC screening of the general population in East Asian and South‐East Asian countries. The fecal occult blood test is widely used for CRC screening in these countries, and its effectiveness in reducing CRC incidence and mortality has been demonstrated; however, the low participation rate in CRC screening programs is a problem to be solved in every country. Improvement in the public awareness of CRC and promotion of CRC screening by physicians will help to raise the participation rate and reduce the number of deaths caused by CRC. Regarding screening colonoscopy, several studies have recently demonstrated its effectiveness in reducing CRC incidence and mortality. However, at present, CRC screening colonoscopy is not adopted as a primary population‐based screening tool because of staffing constraints in relation to large population sizes, increased medical costs, and potential adverse events (e.g. perforation and drug‐induced anaphylaxis). Further study is required to consider colonoscopy as CRC screening that is established in Western countries.

The addition of high magnifying endoscopy improves rates of high confidence optical diagnosis of colorectal polyps

Background and study aims: The real-time optical diagnosis of colorectal polyps with high confidence predictions can achieve high levels of accuracy. Increasing the rates of high confidence optical diagnosis can improve the clinical application of real-time optical diagnosis in routine practice. The primary aim of this prospective study was to evaluate whether high magnifying endoscopy improves the rates of high confidence narrow-band imaging (NBI) – based optical diagnosis for differentiating between neoplastic and non-neoplastic colorectal lesions according to the NBI international colorectal endoscopic (NICE) classification. Patients and methods: Consecutive adult patients undergoing colonoscopy with a high magnifying (maximum, × 80) colonoscope between April and August 2012 were recruited. The optical diagnosis for each polyp was evaluated during colonoscopy in two consecutive stages by the same endoscopist, who first used NBI with non-magnifying endoscopy (NBI-NME), then NBI with magnifying endoscopy (NBI-ME). A level of confidence was assigned to each prediction. Results: The analysis included 124 patients (mean age, 56.4 years; male-to-female ratio, 72:52) with 248 polyps smaller than 10 mm. Of the 248 polyps, 210 were 1 to 5 mm in size and 38 were 6 to 9 mm in size; 77 polyps were hyperplastic, 4 were sessile serrated adenomas/polyps, 160 were low grade adenomas, 5 were high grade adenomas, and 2 were deep submucosal invasive carcinomas. The rate of high confidence optical diagnosis when NBI-ME was used was significantly higher than the rate when NBI-NME was used for diminutive (1 – 5 mm) polyps (92.9 % vs 79.5 %, P < 0.001) and for small (6 – 9 mm) polyps (94.7 % vs 84.2 %, P = 0.048). Conclusion: High magnifying endoscopy significantly improved the rates of high confidence NBI-based optical diagnosis of diminutive and small colorectal polyps. Study registration: UMIN 000007608

Prospective evaluation of the proportion of sessile serrated adenoma/polyps in endoscopically diagnosed colorectal polyps with hyperplastic features

Background and study aims: Sessile serrated adenoma/polyps (SSA/Ps) are considered precursors of colorectal cancers with microsatellite instability. However, it is still difficult to differentiate SSA/Ps from hyperplastic polyps endoscopically; therefore, the prevalence of SSA/Ps remains uncertain in clinical practice. This study aimed to clarify the proportion of SSA/Ps in endoscopically diagnosed colorectal polyps with hyperplastic features (E-HPs). Patients and methods: Patients aged ≥ 40 years undergoing colonoscopy for standard clinical indications at our center were prospectively enrolled between June 2013 and May 2014. During colonoscopy, 0.05 % indigo carmine dye was sprayed throughout the colorectum to highlight lesions. All detected lesions were diagnosed by high definition magnifying narrow-band imaging and were resected endoscopically or surgically, apart from rectosigmoid E-HPs ≤ 5 mm. The number of rectosigmoid E-HPs ≤ 5 mm was recorded, and some were resected for use as tissue samples. Results: A total of 343 patients (male: 42.9 %; mean age: 61.5 years) were included. Among 3838 E-HPs (distal: 96.4 %) detected in 294 patients, 792 were resected and analyzed. All of 21 SSA/Ps identified in 17 patients were included in E-HPs, and the overall proportion of SSA/Ps in E-HPs was 2.7 %. However, this proportion increased with the size of E-HPs (≤ 5 mm: 0.7 %; 6 – 9 mm: 29.0 %; ≥ 10 mm: 70 %) and was higher in the proximal colon than in the distal colorectum (10.9 % vs. 0.9 %). In addition, no SSA/P was found in the rectum, and no SSA/P had cytological dysplasia. Conclusions: The overall proportion of SSA/Ps in E-HPs was 2.7 %, although this proportion was higher in the proximal colon and increased with the size of E-HPs. SSA/Ps were common in routine colonoscopy, with a prevalence of at least 5.0 %. Study registration: UMIN000010832.

Polyp Detection, Characterization, and Management Using Narrow-Band Imaging with/without Magnification.

Narrow-band imaging (NBI) is a new imaging technology that was developed in 2006 and has since spread worldwide. Because of its convenience, NBI has been replacing the role of chromoendoscopy. Here we review the efficacy of NBI with/without magnification for detection, characterization, and management of colorectal polyps, and future perspectives for the technology, including education. Recent studies have shown that the next-generation NBI system can detect significantly more colonic polyps than white light imaging, suggesting that NBI may become the modality of choice from the beginning of screening. The capillary pattern revealed by NBI, and the NBI International Colorectal Endoscopic classification are helpful for prediction of histology and for estimating the depth of invasion of colorectal cancer. However, NBI with magnifying colonoscopy is not superior to magnifying chromoendoscopy for estimation of invasion depth. Currently, therefore, chromoendoscopy should also be performed additionally if deep submucosal invasive cancer is suspected. If endoscopists become able to accurately estimate colorectal polyp pathology using NBI, this will allow adenomatous polyps to be resected and discarded; thus, reducing both the risk of polypectomy and costs. In order to achieve this goal, a suitable system for education and training in in vivo diagnostics will be necessary.

Five Cases with Ectopic Esophageal Sebaceous Glands

Abstract: Sebaceous glands in the esophagus are considered to be rare and are of particular interest because of their as yet unknown origin. Six postmortem and 48 antemortem cases with this condition have been reported. We report herein five cases diagnosed by endoscopy and biopsy, with a review of the pertinent literature. The hypotheses that gastroesophageal reflux disease (GERD), alcohol consumption, smoking, and hyperlipidemia play roles in the pathogenesis of ectopic sebaceous glands of the esophagus are not supported by current evidence. Given the gradual increase in reports of adult cases with ectopic esophageal sebaceous glands, we suspect that these lesions may not be as rare as generally assumed.

Superficial anal canal squamous cell carcinoma diagnosed using narrow-band imaging and treated by endoscopic submucosal dissection.

Double-balloon endoscopy (DBE) is a useful method to detect and treat small bowel bleeding. Although DBE allows us to have therapeutic options, the rate of rebleeding is high in Dieulafoy’s lesions even after endoscopic hemostasis. Recently, endoscopic band ligation (EBL) has been applied to the treatment of small bowel bleeding. We report a case of small bowel bleeding from Dieulafoy’s lesions that was successfully treated with EBL using DBE. A 95-year-old womanwith a past medical history of chronic cardiac failure and chronic kidney disease was admitted with episodes of melena for 3 days. Hemoglobin level on admission was 4.3mg/dL. Bleeding source was not found by esophagogastroduodenoscopy and colonoscopy. Although video capsule endoscopy (PillCam SB2; Covidien, Tokyo, Japan) did not reveal active bleeding, the bleeding site was suspected in the jejunum. Antegrade DBE (EN-450P5/20; Fujifilm Co., Tokyo, Japan) was done using pethidine hydrochloride and enabled us to detect Dieulafoy’s lesion in the upper jejunum. Although endoscopic clipping was tried at first, the hemoclip could not be deployed at the targeted lesion located in the opposite direction of the working channel of the enteroscope. Therefore, EBL was selected (Fig. 1). After the lesion was marked with a hemoclip, the enteroscope was removed. The endoscope was reinserted after a band-ligator device (MD-48710 EVL Devices; Sumitomo Bakelite Co. Ltd, Tokyo, Japan) was attached to the tip. The lesion was sucked into the ligator cup, and the O-band was released. The initial hemostasis was successful. Total procedure time was 59min. Complications such as perforation or abscess formation did not occur. There was no rebleeding during the follow-up period of 30days. This is the first report applying EBL toDieulafoy’s lesion in the jejunum using DBE. EBL with DBE may be considered a safe and effective therapy in the treatment of Dieulafoy’s lesion in the jejunum. Authors declare no conflict of interests for this article.

A case report of undifferentiated carcinoma with osteoclast-like giant cells of the pancreas and literature review

Osteoclast-like giant cell tumors rarely arise in the pancreas. Here we report the case of a 78-year-old woman who was diagnosed with a well-defined 3 cm multilocular mass in the pancreatic body by the use of ultrasonography, computed tomography and magnetic resonance imaging. The rim and the septa of the tumor were well enhanced. The distal pancreas was removed with the spleen and the peripancreatic lymph nodes. Macroscopically, the mass was composed predominantly of a multilocular cystic tumor filled with hemorrhagic necrosis, and partly composed of solid components. A histopathological study showed a proliferation of multinucleated osteoclast-like giant cells and spindle cells. Although the predominant tumor cells were strongly positive for vimentin and CD68 and negative for epithelial markers, there were some sparsely scattered cytokeratin-positive neoplastic glands. Seventeen months after surgery, the patient is still alive and has had no recurrence. Below we review 32 cases of osteoclast-like giant cell tumor of the pancreas that have been reported in English literature since 2000.

Postherpetic pseudohernia: delayed onset of paresis of abdominal muscles due to herpes zoster causing an ipsilateral abdominal bulge

Postherpetic pseudohernia causes an abdominal bulge as well as an abdominal wall herniation. This disease is one of the neurological complications of herpes zoster and essentially consists of paresis of ipsilateral abdominal muscles. Postherpetic pseudohernia may be mistaken for abdominal wall herniation because it is not well known. We describe two cases presenting an abdominal bulge. The ipsilateral abdominal bulge appeared after recovery from abdominal zoster. Abdominal CT showed no evidence of a herniation or mass. We diagnosed a postherpetic pseudohernia. One of the patients recovered spontaneously 4 months after the onset, and the other partially recovered after 2 months. This disease can be expected to disappear spontaneously, unlike abdominal herniation requiring surgery. It has been reported that 79.3% of patients eventually recovered spontaneously. For surgeons and general practitioners, it is beneficial to keep this disease in mind when examining a patient presenting an abdominal bulge.

Prospective real-time evaluation of diagnostic performance using endocytoscopy in differentiating neoplasia from non-neoplasia for colorectal diminutive polyps (≤ 5 mm)

AIM To clarify the diagnostic performance of endocytoscopy for differentiation between neoplastic and non-neoplastic colorectal diminutive polyps. METHODS Patients who underwent endocytoscopy between October and December 2016 at Sano Hospital were prospectively recruited. When diminutive polyps (≤ 5 mm) were detected, the lesions were evaluated by endocytoscopy after being stained with 0.05% crystal violet and 1% methylene blue. The diminutive polyps were classified into five categories (EC 1a, 1b, 2, 3a, and 3b). Endoscopists were asked to take a biopsy from any lesion diagnosed as EC1b (indicator of hyperplastic polyp) or EC2 (indicator of adenoma). We have assessed the diagnostic performance of endocytoscopy for EC2 and EC1b lesions by comparison with the histopathology of the biopsy specimen. RESULTS A total of 39 patients with 63 diminutive polyps were analyzed. All polyps were evaluated by endocytoscopy. The mean polyp size was 3.3 ± 0.9 mm. Among the 63 diminutive polyps, 60 were flat and 3 were pedunculated. The mean time required for EC observation, including the time for staining with crystal violet and methylene blue, was 3.0 ± 1.9 min. Histopathologic evaluation showed that 13 polyps were hyperplastic and 50 were adenomas. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of EC2 for adenoma compared with EC1b for hyperplastic polyp were 98.0%, 92.3%, 96.8%, 98.0% and 92.3%, respectively. There were only two cases of disagreement between the endoscopic diagnosis made by endocytoscopy and the corresponding histopathological diagnosis. CONCLUSION Endocytoscopy showed a high diagnostic performance for differentiating between neoplastic and non-neoplastic colorectal diminutive polyps, and therefore has the potential to be used for “real-time histopathology”.