Northern Yokohama Hospital Research Articles

Intrapartum prophylactic efficacy of ampicillin versus clindamycin in preventing vertical transmission of group B Streptococcus.

To compare the prophylactic efficacy of ampicillin and clindamycin against vertical transmission of group B Streptococcus from mothers to their infants by evaluating the rates of group B Streptococcus colonisation. We retrospectively extracted data for mothers who delivered at Showa University Northern Yokohama Hospital between 1 October 2017 and 31 March 2021 and tested positive for antepartum group B Streptococcus, and their infants. The chi-square test was used to compare the rates of group B Streptococcus colonisation, sepsis, and meningitis. We conducted a multivariate logistic regression analysis, including the time interval between membrane rupture and delivery, chorioamnionitis, and maternal intrapartum fever (≥38.0°C). Two hundred fifty-nine mothers and their infants were eligible. Ampicillin and clindamycin were administered to 150 and 109 mothers, respectively. In the ampicillin and clindamycin groups, 12.0% (18/150) and 37.6% (41/109) infants were group B Streptococcus positive, respectively. The rate of group B Streptococcus colonisation among infants was significantly lower in the ampicillin group (p < 0.001). Multivariate regression analysis showed similar results (p < 0.001). No sepsis or meningitis cases were observed in either group. Prophylactic efficacy of clindamycin against the vertical transmission of group B Streptococcus is lower than that of ampicillin.

Factors Associated With Physical Restraints in a Psychiatric Unit in Japan: a Retrospective Study.

To identify factors associated with the use and duration of physical restraint (PR) in a psychiatric unit in Japan. Medical records of 1308 patients admitted first time to the psychiatric emergency unit of Showa University Northern Yokohama Hospital between 1 January 2014 and 31 December 2021 were retrospectively reviewed. Data collected included patient age, sex, outpatient treatment, living arrangements, disability pension status, diagnosis (based on ICD-10), and psychotropic medication use at admission (chlorpromazine equivalent dose, imipramine equivalent dose, diazepam equivalent dose, and number of mood stabilisers administered). Logistic regression analysis and multiple regression analysis were used to identify factors associated with the use and duration of PR, respectively. Of 1308 patients, 399 (30.5%) were subjected to PR and 909 (69.5%) were not. Among the 399 patients subjected to PR, 54 were excluded from the multiple regression analysis for duration of PR as they remained subject to PR on the day of discharge. The remaining 345 patients were subject to PR for a median of 10 days. PR utilisation was associated with male sex (odds ratio [OR] = 1.420), treatment at our hospital (OR = 0.260), treatment at other hospitals (OR = 0.645), F3 diagnosis (depression) [OR = 0.290], F4-9 diagnosis (OR = 0.309), and imipramine equivalent dose at admission (unit OR = 0.994). The log-transformed duration of PR was independently associated with the age group of 50 to 69 years (β = 0.248), the age group of ≥70 years (β = 0.274), receiving a disability pension (β = 0.153), an F1 diagnosis (β = -0.187), an F4-9 diagnosis (β = -0.182), chlorpromazine equivalent dose at admission (β = 0.0004), and number of mood stabilisers administered at admission (β = -0.270). Identifying factors associated with the use and duration of PR may lead to reduction in the use and duration of PR.

Encouraging outpatients in an acute hospital for the relief of cancer-related pain: a qualitative study

PurposeTo identify the processes of cancer-related pain relief and exacerbation faced by outpatients in an acute care hospital and to examine the support needed for outpatient pain control.MethodsWe conducted semi-structured, in-depth interviews with patients from the outpatient department of Showa University Northern Yokohama Hospital in Kanagawa Prefecture, Japan. Participants were recruited by purposive sampling. From the recorded data, verbatim transcripts were made and used as textual data for analysis by consistent comparative method.ResultsBetween April 2018 and April 2022, interviews were conducted with 30 participants. Analysis of the verbatim transcripts generated 13 categories from 27 concepts. Category relationships were examined, and a conceptual framework was developed. Outpatients went from being in a state of hesitation towards consultation with medical professionals to receiving individual consistent follow-ups by medical professionals in the hospital and community pharmacies, which led to patient teleconsultations when their physical condition changed, leading to an improvement of pain.ConclusionThe process of relief and exacerbation of cancer-related pain experienced by outpatients in the acute care hospital reveals that the provision of consistent follow-up through remote or in-person interviews has an important role to play in pain management, as it helps to build relationships between patients and medical professionals. Alternatively, when outpatients exhibited endurance, their pain worsened, and they fell into a negative cycle of poor pain control.

The Pros and Cons of Artificial Intelligence in Endoscopy.

1Humanitas University, Department of Biomedical Sciences, Pieve Emanuele, Italy 2Humanitas Clinical and Research Center –IRCCS-, Endoscopy Unit, Rozzano, Italy. 3Clinical Effectiveness Research Group, University of Oslo, Oslo, Norway 4Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama, Japan 5University of Kansas School of Medicine and VA Medical Center, Kansas City, United States

Differences in the clinical characteristics of Kawasaki disease between older and younger children (2015-2019): A single-center, retrospective study.

The objective of this study was to investigate the differences in the clinical characteristics of Kawasaki disease between older and younger children. This retrospective study examined 405 children with Kawasaki disease admitted to Showa University Northern Yokohama Hospital between 2015 and2019. Eligible patients were classified into the older (≥3.0years of age, n=169) and younger (<3.0years of age, n=236) groups. Skin rash was found in significantly fewer cases (112 [66.3%] vs 229 [97.0%], P<.001 in the younger group). Cervical lymphadenopathy was more common in older children (153 [90.5%] vs 165 [69.9%], P<.001) and in incomplete Kawasaki disease (3 or 4 findings) (34 [20.1%] vs 25 [10.6%], P=.0078). The diagnosis was more delayed in older children (median: 5.0days vs 4.0days, P=.003) than the younger group. Additionally, fever nonresponsive to a single intravenous immunoglobulin was more common, and the duration of fever was significantly longer in the older group (48 [28.4%] vs 47 [19.9%], P=.0479). Kawasaki disease should be suspected in children aged >3.0years with cervical lymphadenopathy and fever, despite the absence of skin rash. Additionally, incomplete Kawasaki disease, fever unresolved by a single intravenous immunoglobulin infusion, and the tendency to delay treatment initiation are more common in children aged >3.0years.

Thyroid dysfunction with atezolizumab plus bevacizumab after lenvatinib in hepatocellular carcinoma: A case series

Atezolizumab plus bevacizumab is the recommended first-line treatment for unresectable hepatocellular carcinoma, based on guidelines from the Barcelona Clinic Liver Cancer prognosis and treatment strategy. However, atezolizumab plus bevacizumab may be used after administration of lenvatinib. Here, we present four patients who developed thyroid dysfunction after second-line treatment with atezolizumab plus bevacizumab, but not after lenvatinib alone. The patients were treated with lenvatinib and/or atezolizumab plus bevacizumab for unresectable hepatocellular carcinoma at Showa University Northern Yokohama Hospital. Of patients treated with only lenvatinib or atezolizumab plus bevacizumab, 2/18 (11%) and 4/15 (27%) developed thyroid dysfunction, respectively. All four patients treated with atezolizumab plus bevacizumab after lenvatinib developed hypothyroidism after 2-14 doses of atezolizumab plus bevacizumab. Three patients developed Grade 2 symptoms and were treated with levothyroxine sodium. In patients with hepatocellular carcinoma, the incidence of thyroid dysfunction may be higher among patients treated with atezolizumab plus bevacizumab after lenvatinib than those treated with lenvatinib or atezolizumab plus bevacizumab alone.

Obesity is not a risk factor for either mortality or complications after laparoscopic cholecystectomy for cholecystitis

Obesity is a positive predictor of surgical morbidity. There are few reports of laparoscopic cholecystectomy (LC) outcomes in obese patients. This study aimed to clarify this relationship. This retrospective study included patients who underwent LC at Showa University Northern Yokohama Hospital between January 2017 and April 2020. A total of 563 cases were examined and divided into two groups: obese (n = 142) (BMI ≥ 25 kg/m2) and non-obese (n = 241) (BMI < 25 kg/m2). The non-obese group had more female patients (54%), whereas the obese group had more male patients (59.1%). The obese group was younger (56.6 years). Preoperative laboratory data of liver function were within the normal range. The obese group had a significantly higher white blood cell (WBC) count (6420/μL), although this was within normal range. Operative time was significantly longer in the obese group (p = 0.0001). However, blood loss and conversion rate were not significantly different among the groups, neither were surgical outcomes, including postoperative hospital stay and complications. Male sex and previous abdominal surgery were risk factors for conversion, and only advanced age (≥ 79 years) was an independent predictor of postoperative complications as observed in the multivariate analysis. Although the operation time was prolonged in obese patients, operative factors and outcomes were not. Therefore, LC could be safely performed in obese patients with similar efficacy as in non-obese patients.

The association between age and adverse events due to biologic disease-modifying antirheumatic drugs in patients with rheumatoid arthritis: A retrospective cohort study.

We examined whether the age of patients with rheumatoid arthritis was associated with adverse events (AEs) caused by biologic disease-modifying antirheumatic drugs (bDMARDs).Patients with rheumatoid arthritis using bDMARDs from Showa University Hospital, Showa University Northern Yokohama Hospital, and Showa University Koto Toyosu Hospital from January 2005 to December 2017 were eligible for this retrospective cohort study. The maximum observation period was determined to be 1 year. Outcomes in patients older and younger than 75 years were compared. The primary outcome was the rate of drug discontinuation because of AEs caused by bDMARDs. Univariate and multivariate analyses were performed using Pearson's chi-squared test and logistic regression analysis, respectively.A total of 416 patients were enrolled; median (interquartile range [IQR]): 60.0 (44.3 - 71.0) years and 84.6% women; patients ≥ 75 years were 67/416 (16.1%). The rates of drug discontinuation because of AEs caused by bDMARDs were 10.5% (7/67) in patients 75 years and older and 10.9% (38/349) in those younger than 75 years (relative risk 0.95, 95% confidential interval 0.45-2.24). In logistic regression analysis adjusted for covariates, the rate of drug discontinuation showed no significant difference between the patients ≥ 75 years and the those < 75 years (adjusted odds ratio 0.70, 95% confidential interval 0.29-1.75, P = .45).The rate of drug discontinuation because of AEs caused by bDMARDs was not significantly different between patients 75 years and older and patients younger than 75 years.

Left-sided location is a risk factor for lymph node metastasis of T1 colorectal cancer: a single-center retrospective study

PurposeAlthough some studies have reported differences in clinicopathological features between left- and right-sided advanced colorectal cancer (CRC), there are few reports regarding early-stage disease. In this study, we aimed to compare the clinicopathological features of left- and right-sided T1 CRC.MethodsSubjects were 1142 cases with T1 CRC undergoing surgical or endoscopic resection between 2001 and 2018 at Showa University Northern Yokohama Hospital. Of these, 776 cases were left-sided (descending colon to rectum) and 366 cases were right-sided (cecum to transverse colon). We compared clinical (patients age, sex, tumor size, morphology, initial treatment) and pathological features (invasion depth, histological grade, lymphatic invasion, vascular invasion, tumor budding) including lymph node metastasis (LNM).ResultsLeft-sided T1 CRC showed significantly higher rates of LNM (left-sided 12.0% vs. right-sided 5.4%, P < 0.05) and lymphatic invasion (left-sided 32.7% vs. right-sided 23.2%, P < 0.05). Especially, the sigmoid colon and rectum showed higher rates of LNM (12.4% and 12.1%, respectively) than other locations. Patients with left-sided T1 CRC were younger than those with right-sided T1 CRC (64.9 years ±11.5 years vs. 68.7 ± 11.6 years, P < 0.05), as well as significantly lower rates of poorly differentiated carcinoma/mucinous carcinoma than right-sided T1 CRC (11.6% vs. 16.1%, P < 0.05).ConclusionLeft-sided T1 CRC, especially in the sigmoid colon and rectum, exhibited higher rates of LNM than right-sided T1 CRC, followed by higher rates of lymphatic invasion. These results suggest that tumor location should be considered in decisions regarding additional surgery after endoscopic resection.Trial registrationThis study was registered with the University Hospital Medical Network Clinical Trials Registry (UMIN 000032733).

Treatment policy for colonic laterally spreading tumors based on each clinicopathologic feature of 4 subtypes: actual status of pseudo-depressed type

Laterally spreading tumors (LSTs) are originally classified into 4 subtypes. Pseudo-depressed nongranular types (LSTs-NG-PD) are gaining attention because of their high malignancy potential. Previous studies discussed the classification of nongranular (LST-NG) and granular types (LST-G); however, the actual condition or indication for endoscopic treatment of LSTs-NG-PD remains unclear. We aimed to compare the submucosal invasion pattern of LSTs-NG-PD with the other 3 subtypes. A total of 22,987 colonic neoplasms including 2822 LSTs were resected endoscopically or surgically at Showa University Northern Yokohama Hospital. In these LSTs, 322 (11.4%) were submucosal invasive carcinomas. We retrospectively evaluated the clinicopathologic features of LSTs divided into 4 subtypes. In 267 LSTs resected en bloc, their submucosal invasion site was further evaluated. The frequency of LSTs in all colonic neoplasms was significantly higher in women (14.9%) than in men (11.0%). Rates of submucosal invasive carcinoma were .8% in the granular homogenous type (LSTs-G-H), 15.2% in the granular nodular mixed type (LSTs-G-M), 8.0% in the nongranular flat elevated type (LSTs-NG-F), and 42.5% in LSTs-NG-PD. Tumor size was associated with submucosal invasion rate in LSTs-NG-F and LSTs-NG-PD (P< .001). The multifocal invasion rate of LSTs-NG-PD (46.9%) was significantly higher than that of LSTs-G-M (7.9%) or LSTs-NG-F (11.8%). In LSTs-NG-PD, the invasion was significantly deeper (≥1000 μm) if observed in 1 site. For LSTs-G-M and LSTs-NG-F that may have invaded the submucosa, en bloc resection could be considered. Considering that LSTs-NG-PD had a higher submucosal invasion rate, more multifocal invasive nature, and deeper invasion tendency, regardless if invasion was only observed in 1 site, than LSTs-NG-F, we should endoscopically distinguish LSTs-NG-PD from LSTs-NG-F and strictly adopt en bloc resection by endoscopic submucosal dissection or surgery for LSTs-NG-PD. (Clinical trial registration number: UMIN 000020261.).

Current Status of Low-dose CT Screening for Lung Cancer in Ningen Dock of Showa University Northern Yokohama Hospital

Current Status of Low-dose CT Screening for Lung Cancer in Ningen Dock of Showa University Northern Yokohama Hospital

Showa University Northern Yokohama Hospital

Showa University Northern Yokohama Hospital

Safety and curability of laparoscopic gastrectomy in elderly patients with gastric cancer.

Elderly patients are often considered as a high-risk population for major abdominal surgery due to reduced functional reserve and increased comorbidities. The aim of this study was to assess the safety and curability of laparoscopic gastrectomy in elderly patients with gastric cancer compared with short- and long-term outcomes in non-elderly patients. We retrospectively investigated 386 patients who underwent laparoscopic gastrectomy for gastric cancer between January 2007 and December 2015at the Digestive Disease Center, Showa University, Northern Yokohama Hospital. We categorized the patients into two groups by age: the elderly patients (≥ 75years old) and the non-elderly patients (< 74years old). Patient characteristics, clinicopathologic and operative findings, and short- and long-term outcomes were investigated and compared between the two groups. The elderly group showed a significantly higher rate of comorbidities (73.1 vs. 49.2%, P < 0.001), and American Society of Anesthesiologists (ASA) scores ≥ 2 (76.3 vs. 43.7%, P < 0.001), and using anticoagulant agents (25.8 vs. 7.9%, P < 0.001) than the non-elderly group. The postoperative morbidity and mortality did not differ between the two groups (19.4 vs. 18.8%; P = 0.880, 2.2 vs. 0%; P = 0.058). In the multivariate analysis, male sex was the only risk factor for postoperative morbidity after laparoscopic gastrectomy. However, age was not found to be a risk factor. The 5-year overall survival ratio was significantly lower in the elderly group than in the non-elderly group (67.7 vs. 85.0%; P < 0.001). However, the 5-year disease-specific survival ratio was similar in the two groups (84.8 vs. 89.1%; P = 0.071). Laparoscopic gastrectomy for gastric cancer could be safely performed in elderly patients with acceptable postoperative morbidity and curability.

Expression of matrix metalloproteinase-7 correlates with the invasion of T1 colorectal carcinoma.

T1 colorectal carcinomas (CRCs) are an initial site of metastatic spread. Various risk factors for lymph node metastasis have been investigated in T1 CRCs. However, the major step in the entire process of metastasis remains unclear. In terms of carcinoma invasion and metastasis, matrix metalloproteinases (MMPs) have recently gained increasing attention. Notably, MMP-7 is frequently overexpressed in CRCs, but its implication has not been determined in T1 CRCs yet. The present study aimed to clarify the associations between the pathological risk factors of T1 CRCs and MMP-7. In the current study, 211 lesions of T1 CRC that were resected endoscopically or surgically at Showa University Northern Yokohama Hospital (Yokohama, Japan) between April 2008 and December 2009 were retrospectively analyzed. MMP-7 was immunostained and evaluated by its frequency of expression. Pathological factors of T1 CRCs were analyzed in association with MMP-7 expression. Furthermore, the ultrastructural alterations of carcinoma invasion were examined using low vacuum-scanning electron microscopy (LV-SEM). MMP-7 expression was associated with venous invasion (P=0.005), and LV-SEM revealed the disappearance of the normal structure of collagen and elastic fibers of veins invaded by tumor cells expressing MMP-7. At the invasive front, MMP-7 has a vital role in carcinoma invasion, correlating with venous invasion of T1 CRCs.

Effects of preoperative cinacalcet hydrochloride treatment on the operative course of parathyroidectomy and pathological changes in resected parathyroid glands

BackgroundSecondary hyperparathyroidism (SHPT) is associated with higher cardiovascular risk and mortality in patients undergoing dialysis. Cinacalcet hydrochloride (CH), which has been clinically available in Japan since 2008, could effectively reduce parathyroid hormone (PTH) levels even in patients with severe SHPT. However, parathyroidectomy (PTx) is performed in patients with severe SHPT refractory to CH. This study investigated the effects of preoperative CH treatment on the operative course and pathological findings of resected parathyroid glands (PTGs) in patients undergoing PTx.MethodsWe retrospectively analyzed 194 PTx cases for SHPT in long-term hemodialysis patients at Showa University Northern Yokohama Hospital from April 2002 to March 2014.ResultsA total of 45 patients were administered CH before PTx (CH group), and 149 patients never received CH (non-CH group). No significant difference was seen in intact PTH levels, the number of resected PTGs, or operative time between the two groups. However, the total volume of all PTGs and the volume of the largest PTG were significantly lower in the CH than in the non-CH group. Patients with PTG adhesion to surrounding tissues were significantly more prevalent in the CH than in the non-CH group. In addition, cystic changes or hemorrhagic necrosis in the resected PTGs was observed more frequently in the CH group than in the non-CH group.ConclusionsThe results of the present study suggest that preoperative CH treatment might introduce pathological changes in resected PTGs in PTx for severe SHPT, but it does not affect the operative time.

Retrospective analysis of large bowel obstruction or perforation caused by oral preparation for colonoscopy.

Background and study aims Patients undergoing bowel preparation for colonoscopy are at risk of potentially severe adverse events such as large-bowel obstruction (LBO) and perforation. These patients usually need emergency surgery and the consequences may be fatal. Little is known about the risk factors for LBO and perforation in these circumstances. We sought to establish the natural history of LBO and perforation caused by oral preparation for colonoscopy. Patients and methods We retrospectively analyzed data from 20 patients with LBO or perforation associated with oral preparation for colonoscopy. All patients were treated at the Showa University Northern Yokohama Hospital (SUNYH) between April 2001 and December 2015. Drugs used for bowel preparation, age, sex, indication for colonoscopy, pathogenesis and treatment were recorded. Results Eighteen of the patients had LBO and 2 had perforation. Fourteen events occurred at SUNYH, which accounted for 0.016 % of patients who underwent bowel preparation during this period. Seventeen patients were symptomatic when the decision to undertake colonoscopy was made (including 7 who complained of constipation and 4 who complained of abdominal pain; 3e were asymptomatic). Nineteen patients ultimately required surgery, 13 within 3 days of presentation. Eleven patients ultimately required colostomy. There was no perioperative mortality in our cases. Conclusion Large bowel obstruction and perforation are rare events associated with oral preparation for colonoscopy, but frequently require surgery. Exacerbation of constipation might be a risk factor for LBO or perforation. Potentially catastrophic situations can be avoided by early detection and treatment.

Comparative clinicopathological characteristics of colon and rectal T1 carcinoma.

Lymph node metastasis significantly influences the management of patients with colorectal carcinoma. It has been observed that the biology of colorectal carcinoma differs by location. The aim of the current study was to retrospectively compare the clinicopathological characteristics of patients with colon and rectal T1 carcinomas, particularly their rates of lymph node metastasis. Of the 19,864 patients who underwent endoscopic or surgical resection of colorectal neoplasms at Showa University Northern Yokohama Hospital, 557 had T1 surgically resected carcinomas, including 457 patients with colon T1 carcinomas and 100 patients with rectal T1 carcinomas. Analysed clinicopathological features included patient age, gender, tumor size, morphology, tumor budding, invasion depth, vascular invasion, histological grade, lymphatic invasion and lymph node metastasis. Rectal T1 carcinomas were significantly larger than colon T1 carcinomas (mean ± standard deviation: 23.7±13.1 mm vs. 19.9±11.0 mm, P<0.01) and were accompanied by significantly higher rates of vascular invasion (48.0% vs. 30.2%, P<0.01). Significant differences were not observed among any other clinicopathological factors. In conclusion, tumor location itself was not a risk factor for lymph node metastasis in colorectal T1 carcinomas, even though on average, rectal T1 carcinomas were larger and accompanied by a significantly higher rate of vascular invasion than colon T1 carcinomas.

Su1702 Diagnostic Characteristics of Depressed Type Colorectal Neoplasms Examined With Magnifying Chromo-Endoscopy and Endocytoscopy

Su1702 Diagnostic Characteristics of Depressed Type Colorectal Neoplasms Examined With Magnifying Chromo-Endoscopy and Endocytoscopy Shin-Ei Kudo*, Kazuki Kato, Katsuro Ichimasa, Hideyuki Miyachi, Yuta Kouyama, Shingo Matsudaira, Hiromasa Oikawa, Tomokazu Hisayuki, Yui J. Kimura, Yuichi Mori, Masashi Misawa, Toyoki Kudo, Kenta Kodama, Kunihiko Wakamura, Takemasa Hayashi, Atsushi Katagiri, Eiji Hidaka, Fumio Ishida Showa University Northern Yokohama Hospital, Yokohama, Japan Introduction & Aim: Colorectal carcinomas are generally recognized to develop from sessile-type “polyps”. This “adenoma-carcinoma sequence” theory has been in the mainstream of development of colorectal cancers. But recently the existence of many depressed-type cancers has been revealed, which are considered to emerge directly from normal epithelium, not through the adenomatous stage. This theory is called “de novo” pathway. Now, it is possible to estimate the histology of colorectal lesions using magnifying chromo-endoscopy (pit pattern classification) and endocytoscopy (EC) which can observe not only the structural atypia but also the cellular atypia in living colorectal lesions. The aim is to clarify the diagnostic characteristics of depressed-type colorectal neoplasms, demonstrating the validity of pit pattern diagnosis and EC classification. Methods: A total of 22903 colorectal neoplasms excluding advanced carcinomas were resected endoscopically or surgically in our unit from April 2001 to June 2014. Of these, 14522 lesions were low-grade dysplasia, 4956 were high-grade dysplasia and 968 were submucosally invasive (T1) carcinomas. According to morphological/development classification, they were divided into 3 types: depressed, flat and sessile type. We investigated the rate of T1 carcinomas and the characteristics of depressed-type neoplasms concerning pit pattern and EC classification. Results: The rate of T1 carcinomas in depressed-type lesions reached to 63.7 %, meanwhile that in flat-type and sessile-type lesions was 4.1 % and 3.1 %, respectively. Within less than 5mm in diameter, that was 10.2 %, 0 % and 0.06 %, respectively. Most (88.3 % and 91.2 %) of the flat-type and sessile-type lesions showed type IIIL or IV pit pattern corresponding to adenomas, whereas 94.5 % of the depressed-type lesions were characterized by type IIIs, VI or VN pit pattern corresponding to carcinomas. As for endocytoscopy, most of the flatand sessile-type lesions showed EC2 corresponding to adenomas. In contrast, the depressed-type lesions were observed as EC3a (23.5 %) and EC3b (74.1 %) corresponding to invasive carcinomas. Conclusion: This study revealed the diagnostic characteristics of depressed-type lesions. They show typically type IIIs, VI or VN pit patterns in magnifying endoscopy and type EC3a or EC3b in endocytoscopy. These lesions tend to invade the submucosal layer even when they are small. Therefore, more careful endoscopic diagnosis of ‘whether the lesion is depressed type or not’ would be important.

Sa1591 The Diagnostic Ability of Micro Vascular Pattern Observed by Endocytoscopy

Sa1591 The Diagnostic Ability of Micro Vascular Pattern Observed by Endocytoscopy

Su1703 High Definition Colonoscopy With I-SCAN and Digital Chromoendoscopy in the Pit Pattern Analysis: a Single Center Experience

Su1702 Diagnostic Characteristics of Depressed Type Colorectal Neoplasms Examined With Magnifying Chromo-Endoscopy and Endocytoscopy Shin-Ei Kudo*, Kazuki Kato, Katsuro Ichimasa, Hideyuki Miyachi, Yuta Kouyama, Shingo Matsudaira, Hiromasa Oikawa, Tomokazu Hisayuki, Yui J. Kimura, Yuichi Mori, Masashi Misawa, Toyoki Kudo, Kenta Kodama, Kunihiko Wakamura, Takemasa Hayashi, Atsushi Katagiri, Eiji Hidaka, Fumio Ishida Showa University Northern Yokohama Hospital, Yokohama, Japan Introduction & Aim: Colorectal carcinomas are generally recognized to develop from sessile-type “polyps”. This “adenoma-carcinoma sequence” theory has been in the mainstream of development of colorectal cancers. But recently the existence of many depressed-type cancers has been revealed, which are considered to emerge directly from normal epithelium, not through the adenomatous stage. This theory is called “de novo” pathway. Now, it is possible to estimate the histology of colorectal lesions using magnifying chromo-endoscopy (pit pattern classification) and endocytoscopy (EC) which can observe not only the structural atypia but also the cellular atypia in living colorectal lesions. The aim is to clarify the diagnostic characteristics of depressed-type colorectal neoplasms, demonstrating the validity of pit pattern diagnosis and EC classification. Methods: A total of 22903 colorectal neoplasms excluding advanced carcinomas were resected endoscopically or surgically in our unit from April 2001 to June 2014. Of these, 14522 lesions were low-grade dysplasia, 4956 were high-grade dysplasia and 968 were submucosally invasive (T1) carcinomas. According to morphological/development classification, they were divided into 3 types: depressed, flat and sessile type. We investigated the rate of T1 carcinomas and the characteristics of depressed-type neoplasms concerning pit pattern and EC classification. Results: The rate of T1 carcinomas in depressed-type lesions reached to 63.7 %, meanwhile that in flat-type and sessile-type lesions was 4.1 % and 3.1 %, respectively. Within less than 5mm in diameter, that was 10.2 %, 0 % and 0.06 %, respectively. Most (88.3 % and 91.2 %) of the flat-type and sessile-type lesions showed type IIIL or IV pit pattern corresponding to adenomas, whereas 94.5 % of the depressed-type lesions were characterized by type IIIs, VI or VN pit pattern corresponding to carcinomas. As for endocytoscopy, most of the flatand sessile-type lesions showed EC2 corresponding to adenomas. In contrast, the depressed-type lesions were observed as EC3a (23.5 %) and EC3b (74.1 %) corresponding to invasive carcinomas. Conclusion: This study revealed the diagnostic characteristics of depressed-type lesions. They show typically type IIIs, VI or VN pit patterns in magnifying endoscopy and type EC3a or EC3b in endocytoscopy. These lesions tend to invade the submucosal layer even when they are small. Therefore, more careful endoscopic diagnosis of ‘whether the lesion is depressed type or not’ would be important.