Laparoscopic left hepatectomy in a goat as a training model for laparoscopic anatomic liver resection: results of training courses with a total of 70 goats

BACKGROUND

To create a suitable animal model for the training of laparoscopic anatomic liver resection, we performed left hepatectomy using a goat and found its suitability. We have since started using goats for wet-lab training and have gradually standardized the relevant procedures. Herein, we report our standardized training procedures using a goat and discuss its feasibility as a novel training model.

METHODS

The standardized wet-lab training courses of laparoscopic liver resection conducted on 62 tables with a total of 70 goats were reviewed. The training course began by encircling the hepatoduodenal ligament for the Pringle maneuver, which was repeated during the parenchymal dissection. Following partial liver resection of the left lateral section, left hepatectomy was performed by a standardized procedure for humans in which the liver was split, exposing the entire length of the middle hepatic vein trunk from the dorsal side after extrahepatic transection of the left Glissonean pedicle. If a goat deceased before initiating left hepatectomy, the training was restarted with a new goat. The surgical procedures were performed by surgeons of varying skill levels.

RESULTS

A total of 184 surgeons including 10 surgical residents participated in the training. Partial liver resection was initiated in 62 tables, with 8 (13%) dying during or after the procedure of partial liver resection. Subsequently, left hepatectomy was initiated in 61 and completed in 59 tables (98%), regardless of whether the goat survived or deceased, and was not completed in 2 tables (3%) due to time limitation. In 14 tables (23%), the goats deceased during the procedure, however, the procedure was completed. The causes of death were multifactorial, including massive bleeding, reperfusion injury after the Pringle maneuver, and carbon dioxide gas embolism.

CONCLUSIONS

Left hepatectomy in a goat is useful as a training model for laparoscopic anatomic liver resection.

Evaluation of the Significance of Lymphatic, Microvascular and Perineural Invasion in Patients With Pancreatic Neuroendocrine Neoplasms

BACKGROUND

Some prognostic factors for pancreatic neuroendocrine neoplasms (PanNENs) have been reported; however, the significance of lymphatic, microvascular, and perineural invasion remains unclear. We aimed to clarify the role of these factors in PanNEN recurrence.

PATIENTS AND METHODS

We analyzed 138 patients who underwent curative pancreatectomy and were pathologically diagnosed with PanNEN. We evaluated the association between clinicopathological factors and the recurrence of PanNENs.

RESULTS

The numbers of patients with lymphatic, microvascular, and perineural invasion were 34 (25%), 43 (31%) and 17 (12%), respectively. Twenty-four patients (17%) had recurrences, and the 3, 5, and 10-year recurrence-free survival (RFS) rates were 88%, 84%, and 76%, respectively. The recurrence sites (with duplication) were mainly the liver (twenty-two patients), followed by the lymph nodes (seven patients), and bone (two patients). In multivariate analyses, grade 2-3 and the presence of microvascular invasion were significant risk factors for RFS (hazard ratio=7.5 and 7.9, respectively). When examining outcomes according to these factors, the 5-year RFS rates of patients with risk scores of 0, 1, and 2 were 100%, 91%, and 32%, respectively (p<0.001). Even in patients with grade 1 (n=97) or limited resection (enucleation, splenic-preserving distal pancreatectomy, central pancreatectomy, and duodenum-preserving pancreatic head resection, n=62), the presence of microvascular invasion was a significant risk factor for RFS (hazard ratio=13.4 and 18.0, respectively).

CONCLUSION

The presence of microvascular invasion is an independent risk factor for recurrence in patients with PanNEN.

Evaluation of Early Prognostic Factors in Patients With Pancreatic Ductal Adenocarcinoma Receiving Gemcitabine Together With Nab-paclitaxel

BACKGROUND

Gemcitabine together with nab-paclitaxel (GnP) has been shown to improve outcomes in patients with pancreatic ductal adenocarcinoma (PDAC). However, the predictive markers for treatment effects remain unclear. This study aimed to identify early prognostic factors in patients with PDAC receiving GnP.

PATIENTS AND METHODS

We analyzed 113 patients who received GnP for PDAC and evaluated the relationship between clinical factors and outcomes.

RESULTS

The median survival time (MST) was 1.2 years. In multivariate analysis, baseline carbohydrate antigen 19-9 (CA19-9) ≥747 U/ml [hazard ratio (HR)=1.9], baseline controlling nutrition status (CONUT) score ≥5 (HR=3.7) and changing rate of CA19-9 after two GnP cycles ≥0.69 (HR=3.7) were independent risk factors for poor prognosis. When examining outcomes according to pre-chemotherapeutic measurable factors (baseline CA19-9 and CONUT), the MSTs of patients with pre-chemotherapeutic zero risk factors (pre-low-risk group, n=63) and one or more risk factors (pre-high-risk group, n=50) were 1.7 and 0.65 years (p<0.001), respectively. The MST for those with a changing rate of CA19-9 after two GnP cycles <0.69 and ≥0.69 was significantly different in both groups (2.0 and 1.2 years in the pre-low-risk group, p<0.001; 1.0 and 0.52 years in the pre-high-risk group, p<0.001).

CONCLUSION

These results may be useful for decision-making regarding treatment strategies in patients with PDAC receiving GnP.

Hepatic artery resection without reconstruction in pancreatoduodenectomy

PURPOSE

It has been reported that there are left and right hepatic arterial arcades via the blood vessels around the hilar bile duct; therefore, when the hilar bile duct is preserved, hepatic artery reconstruction may not be necessary. We compared the short-term and long-term outcomes in patients with distal cholangiocarcinoma who underwent pancreatoduodenectomy (PD) with right hepatic artery resection without right hepatic artery reconstruction (RHAR group) with those patients who underwent conventional PD.

METHODS

All data were retrospectively collected from patient records. A 1:4-propensity score-matched case-control study was conducted in patients with distal cholangiocarcinoma who received treatment at Tokyo Women's Medical University from February 1985 to April 2015.

RESULTS

There was no statistical difference in the overall morbidity rate between the two groups. No patient in the RHAR group (10 patients) had liver failure, liver abscess, or cholangitis in the postoperative period; one patient died postoperatively because of a bleeding pseudoaneurysm in the gastroduodenal artery. The PD group (40 patients) had a significantly better median time regarding the recurrence (34 vs. 11 months, p=0.027) and 5-year disease-free survival (35% vs. 10%, p=0.027) rates than the RHAR group, which may be attributed to the presence of a more severe disease in patients in the RHAR group.

CONCLUSION

We concluded that pancreaticoduodenectomy with right hepatic artery resection without reconstruction has a comparable overall morbidity rate with that of a conventional pancreaticoduodenectomy surgery and may be performed as an alternative procedure when tumor invasion of the right hepatic artery is suspected.

Negative prognostic outcomes of percutaneous transhepatic biliary drainage in distal cholangiocarcinoma: a retrospective analysis using propensity score matching

BACKGROUND

The efficacy of different types of preoperative biliary drainage for cholangiocarcinoma has been debated over the past two decades. Controversy concerning the use of percutaneous transhepatic biliary drainage (PTBD) versus endoscopic biliary drainage (EBD) still exists. This study aimed to compare the long-term outcomes between PTBD and EBD in patients with distal cholangiocarcinoma.

METHODS

Data of patients diagnosed with distal cholangiocarcinoma who underwent preoperative PTBD or EBD from January 1999 to December 2017 were analyzed retrospectively. Post-surgical outcomes, including the incidence of post-operative complications, peritoneal metastasis, disease-free survival, and overall survival, were analyzed. Survival analyses were also performed after propensity score matching in the PTBD and EBD groups.

RESULTS

The incidence of post-operative complications was similar in both groups. The 5-year estimated cumulative incidences for peritoneal metastasis were 14.7% and 7.2% in the PTBD and EBD groups, respectively (p = 0.192). The 5-year disease-free survival rates were 23.7% and 47.3% in the PTBD and EBD groups, respectively (p = 0.015). In the multi-variate analysis for overall survival, PTBD was an independent poor prognostic factor. The 5-year overall survival rates were 35.9% and 56.3% in the PTBD and EBD groups, respectively (hazard ratio 1.85, confidence interval 1.05-3.26, p = 0.035). The results after propensity score matching indicated a poorer prognosis in the PTBD group, with a 5-year survival rate of 35.9% in the PTBD group vs 56.0% in the EBD group (p = 0.044).

CONCLUSION

PTBD should be considered as a negative prognostic factor in distal cholangiocarcinoma patients.

Evaluation of the significance of adjuvant chemotherapy in patients with stage ⅠA pancreatic ductal adenocarcinoma

BACKGROUND

Although adjuvant chemotherapy is considered a standard treatment for resected pancreatic ductal adenocarcinoma (PDAC), its utility in stage ⅠA patients is unclear. We aimed to investigate the recurrence rate, surgical outcome, prognostic factors, effectiveness of adjuvant chemotherapy, and determination of groups in whom adjuvant chemotherapy is effective in patients with stage ⅠA PDAC.

METHODS

We retrospectively analyzed 73 patients who underwent pancreatectomy and were pathologically diagnosed with stage ⅠA PDAC between 2000 and 2018. We evaluated the relation between clinicopathological factors, recurrence rates, and outcomes such as the recurrence-free and disease-specific survival rates (RFS and DSS, respectively).

RESULTS

The 5-year RFS and DSS rates were 52% and 58%, respectively. In multivariate analysis, a platelet-to-lymphocyte ratio (PLR) ≥ 170, prognostic nutrition index (PNI) < 47.5, and pathological grade 2 or 3 constituted risk factors for a shorter DSS (hazard ratios: 4.7, 4.6, and 4.1, respectively). Patients with 0-1 of these risk factors (low-risk group; n = 47) had significantly higher 5-year DSS rates than those with 2-3 risk factors (high-risk group; n = 26) (80% vs. 23%; P < 0.001). Patients in the low-risk group showed similar 5-year RFS rates regardless of whether they received or not adjuvant chemotherapy (75% vs 70%, respectively; P = 0.49). Contrarily, high-risk patients who underwent adjuvant chemotherapy had higher 5-year RFS rates than those who did not receive adjuvant chemotherapy (32% vs 0%; P = 0.045).

CONCLUSIONS

In stage IA PDAC, adjuvant chemotherapy seems to be effective only in a subgroup of high-risk patients.

Narrowing of the remnant portal vein diameter and decreased portal vein angle are risk factors for portal vein thrombosis after perihilar cholangiocarcinoma surgery

PURPOSE

To evaluate the incidence, risk factors, management options, and outcomes of portal vein thrombosis following major hepatectomy for perihilar cholangiocarcinoma.

METHODS

A total of 177 perihilar cholangiocarcinoma patients who (1) underwent major hepatectomy and (2) underwent investigating the portal vein morphology, which was measured by rotating the reconstructed three-dimensional images after facilitating bone removal using Aquarius iNtuition workstation between 2002 and 2018, were included. Risk factors were evaluated using the Kaplan-Meier method and Cox proportional hazard models.

RESULTS

Six patients developed portal vein thrombosis (3.4%) within a median time of 6.5 (range 0-22) days. Portal vein and hepatic artery resection were performed in 30% and 6% patients, respectively. A significant difference in the probability of the occurrence of portal vein thrombosis (PV) within 30 days was found among patients with portal vein resection, a postoperative portal vein angle < 100°, remnant portal vein diameter < 5.77 mm, main portal vein diameter > 13.4 mm, and blood loss (log-rank test, p = 0.003, p = 0.06, p < 0.0001, p = 0.01, and p = 0.03, respectively). Decreasing the portal vein angle and narrowing of the remnant PV diameter remained significant predictors on multivariate analysis (p = 0.027 and 0.002, respectively). Reoperation with thrombectomy was performed in four patients, and the other two patients were successfully treated with anticoagulants. All six patients subsequently recovered and were discharged between 25 and 70 days postoperatively.

CONCLUSION

Narrowing of the remnant portal vein diameter and a decreased portal vein angle after major hepatectomy for perihilar cholangiocarcinoma are significant independent risk factors for postoperative portal vein thrombosis.

Negative impact of ultra-thin strut on neointimal coverage condition within one year after implantation as compared to thin sturt in biogradable-polymer sirorimus eluting stents

Background

BIOSCIENCE randomized trial which compared biodegradable-polymer sirolimus-eluting stents with ultra-thin (60μm) strut (ultra-thin BP-SES) and durable-polymer everolimus-eluting stents with thin (81μm) strut (thin DP-EES) have reported that definite stent thrombosis within 1 year had more frequently occurred in ultra-thin BP-SES (0.9%) than in thin DP-EES group (0.4%) although it was not statistically significant. It suggests that neointimal coverage after stent implantation within 1 year might be different between ultra-thin BP-SES and thin DP-EES. Recently, two types of biogradable-polymer sirorimus eluting stents, thin (80μm) strut type (thin BP-SES) and ultra-thin (60μm) strut type (ultra-thin BP-SES), can be available in clinical settings.

Purpose

We compared neointimal coverage conditions between ultra-thin BP-SES and thin BP-SES by optical coherence tomography (OCT).

Methods

Consecutive Forty-six patients who underwent 21 ultra-thin BP-SESs or 25 thin BP-SESs implantation were enrolled. We compared incidences of acute coronary syndrome, type B2/C lesion, atherectomy device use, stent size, stent length, maximum inflation pressure, and 8-month follow-up OCT parameters including proportions of uncovered struts (%Uncovered), malapposed struts, (%Mallaposed) and mean neointimal hyperplasia thickness (mean NHT) between the two groups.

Results

%Uncovered and %malapposed were significantly higher and mean NHT was significantly lower in ultra-thin BP-SES than in thin BP-SES (Table). The other parameters were similar between the two groups.

Conclusion

Ultra-thin BP-SES showed worse neointimal coverage as compared to thin BP-SES within 1 year after stent implantation, which may increase stent thrombosis.

Funding Acknowledgement

Type of funding source: None

Real-world clinical impact of external elastic lamina-based stent sizing criteria using optical coherence tomography

Introduction

ILUMIEN III trial has reported that non-inferiority of optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) to intravascular ultrasound-guided PCI for postprocedural minimum stent area. In the trial, external elastic lamina (EEL)-based stent sizing criteria was introduced, however OCT has limitations including incomplete visualization of EEL in severale lesions.

Purpose

The aim of the study is to investigate real-world clinical impact of EEL-based stent sizing criteria.

Methods

The study included consecutive patients who underwent OCT-guided percutaneous coronary intervention (PCI) for de novo lesions in our institution between September 2016 and April 2018. EEL visibility, mean EEL diameter, mean lumen diameter and plaque morphology were assessed at proximal and distal references. The plaque morphology at references was categorized according to its most prevalent component as follows: normal, fibrous plaque, lipid plaque, and calcified plaque. Both references were divided into 3 groups according to visibility of EEL.

Results

Among 205 lesions, 31 lesions had artifacts at references (16 proximal and 17 distal references). EEL visibility was summarized in a table. Out of 174 lesions with both analyzable references, 111 lesions (63.8%) had &gt;180-degree EEL visibility at both references. Proportion of plaque morphology were significantly different among 3 groups at proximal and distal references as shown in a figure.

Conclusions

EEL-based stent sizing criteria was usable for 63.8% of all the lesions. Vessel size and plaque morphology were significantly associated with EEL visibility.

Proportion of plaque morphology

Funding Acknowledgement

Type of funding source: None

Outcome of contact force-guided radiofrequency catheter ablation or second generation cryoballoon ablation for paroxysmal atrial fibrillation: propensity score matched analysis

Background

Little has been reported on the outcome of contact force (CF)-guided radiofrequency catheter ablation (RFCA) and second generation cryoballoon ablation (CBA).

Purpose

The purpose of this study was to compare the outcome of CF-guided RFCA and second generation CBA for paroxysmal atrial fibrillation (PAF).

Methods

We enrolled the consecutive 364 patients with PAF who underwent initial ablation between September 2014 and July 2018 in our hospital. We compared the late recurrence of atrial tachyarrhythmia more than three months after ablation between RFCA group and CBA group. All RFCA procedures were performed using CF-sensing catheter and all CBA procedures were performed using second generation CB.

Results

There were significant differences in background characteristics: chronic kidney disease, serum brain natriuretic peptide level, and left ventricular ejection fraction. After propensity score matched analysis (Table), atrial tachyarrhythmia free survival was significantly higher in CBA group than in RFCA group (Figure).

Conclusions

Second generation CBA showed a significantly lower late recurrence rate compared to CF-guided RFCA.

Kaplan-Meier Curve

Funding Acknowledgement

Type of funding source: None

Not only power and energy but also balloon size is correlated with lesion formation in laser ablation model in vitro study

Background

Power and total energy were known to correlate with lesion formation during laser balloon ablation for atrial fibrillation. However, it is unclear whether balloon size can influence lesion formation. The aim of this study was to evaluate the impact of balloon size on lesion formation during laser balloon procedure in vitro model.

Methods

Laser energy was applied to chicken muscles using first generation laser balloon. Laser ablation was performed with different 2 balloon size (18mm and 32mm) using 2 different power settings (12W/20sec and 8.5W/20sec). Forty lesions were evaluated for each setting. We compared maximum lesion width, maximum lesion depth, depth at maximum width and endocardial lesion width between 18mm and 32mm balloon groups at 12W/20sec and 8.5W/20sec, respectively.

Results

At 8.5W/20sec, inadequate lesion formation to assess lesion size was observed in 1/40 lesion of 18mm balloon group and in 5/40 lesions of 32mm balloon group. Thus, at 8.5W/20sec 18 mm balloon group consisted of 39 lesions and 32 mm balloon group consisted of 35 lesions. At 12W/20sec 18 mm balloon group consisted of 40 lesions and 32 mm balloon group consisted of 40 lesions. At both power settings, maximum lesion depth was larger in 18mm balloon than in 32mm balloon group. At 12W/20sec setting, maximum lesion width and endocardial width were larger in 32mm balloon group than in 18mm balloon group. At 12W/20sec setting, depth at maximum width was smaller in 32mm balloon group than in 18mm balloon group. Lesion morphologies were summarized in a figure.

Conclusion

Balloon size could affect lesion formation during laser balloon ablation in addition to laser power and energy. Laser ablation lesion were wider but shallower in 32mm balloon group compared with in 18mm balloon group.

Funding Acknowledgement

Type of funding source: None

Clinical outcome of non-use of touch-up focal ablation catheters strategy during cryoballoon atrial fibrillation ablation

Background

It has been reported that frequent use of touch-up focal ablation catheters was related to worse outcomes after cryoballoon (CB) atrial fibrillation (AF) ablation. It is unknown whether non-use of touch-up focal ablation catheters strategy affects the outcome of AF ablation. Therefore, this study aimed to assess whether non-use of touch-up focal ablation catheters strategy improve clinical outcome after AF ablation using CB.

Methods

A total of 151 consecutive patients who received CB ablation from February 2017 to August 2019 were enrolled. Non-use of a touch-up focal ablation catheters strategy was started from February 2018. Patients were divided into 2 groups according to the type of strategy. In the non-touch-up group, pulmonary veins were isolated without touch-up focal ablation catheters as much as possible and in conventional group, touch-up focal ablation catheters were used as required. The 1-year atrial tachyarrhythmia free survival without class 1 or 3 antiarrhythmic drugs after a 90-day blanking period was assessed between the 2 groups.

Results

The conventional group consisted of 76 patients and the non-touch-up group consisted of 75 patients. Baseline characteristics were comparable between 2 groups. Touch-up focal ablation catheters were used more in the conventional group (11 patients, 14%) than non-touch-up group (0 patients, 0%) (p&lt;0.001). Pulmonary isolation was achieved in all patients of both groups. Atrial tachyarrhythmia recurrence occurred more frequently in the non-touch-up group (15/75 patients, 20%) than conventional group (7/76 patients, 9%) (p=0.045).

Conclusion

Non-use of a touch-up focal ablation catheters strategy may be related to worse outcome after CB AF ablation.

Funding Acknowledgement

Type of funding source: None

Multicenter study of novel mapping technique to detect non-pulmonary vein triggers excluding the origin from left atrial posterior wall and superior vena cava

Background

It has been reported that elimination of non-pulmonary vein (PV) triggers after PV isolation is a good predictor of atrial tachyarrhythmia free survival. However, precise mapping of triggers outside from superior vena cava (SVC) or left atrial posterior wall (LAPW) are difficult. The aim of this study is to assess the efficacy of self-reference mapping technique to eliminate non-PV triggers originated from outside of primordial pulmonary vein area.

Methods

Total of 431 patients (446 procedures) underwent atrial fibrillation (AF) ablation in a hospital and in a medical center from January 2017 to March 2019. After isolation of PV, non-PV triggers were induced with isoproterenol and/or adenosine triphosphate. Reproducible non-PV triggers were targeted to ablate using following self-reference mapping technique: A trigger conducts centrifugally and the earliest site should be distinguished from other later activated sites. Using a PentaRay multipolar catheter, the operators annotated the earliest site of local activation and a reference tag was placed. The multipolar catheter was then moved to the reference tag and the process repeated. Ultimately, we identified clusters of early circumferential activation and ablated.

Results

A total of 32 non-PV triggers excluding the origin from LAPW and SVC were induced in 23 patients. Nineteen triggers (59%) were located in the right atrium and 13 triggers (41%) in the left atrium (Figure 1). All triggers were eliminated with ablation and AF was non-inducible in all patients at the end of the procedure. During the follow-up (529±270 days), 18 patients (77%) were free from atrial tachyarrhythmias after a 3-month blanking period. Three patients received additional ablation procedures for recurrent atrial arrhythmias. No non-PV triggers ablated during the previous procedure were observed.

Conclusion

A novel self-reference mapping technique is useful for eliminating non-PV triggers in terms of the short- and long-term success.

Figure 1. Distribution of non-PV triggers

Funding Acknowledgement

Type of funding source: None

Examination of Prognostic Factors Affecting Long-Term Survival of Patients with Stage 3/4 Gallbladder Cancer without Distant Metastasis

In advanced gallbladder cancer (GBC) radical resection, if multiple prognostic factors are present, the outcome may be poor; however, the details remain unclear. To investigate the poor prognostic factors affecting long-term surgical outcome, we examined 157 cases of resected stage 3/4 GBC without distant metastasis between 1985 and 2017. Poor prognostic factors for overall survival and treatment outcomes of a number of predictable preoperative poor prognostic factors were evaluated. The surgical mortality was 4.5%. In multivariate analysis, blood loss, poor histology, liver invasion, and ≥4 regional lymph node metastases (LNMs) were independent prognostic factors for poor surgical outcomes; invasion of the left margin or the entire area of the hepatoduodenal ligament and a Clavien–Dindo classification ≥3 were marginal factors. The analysis identified outcomes of patients with factors that could be predicted preoperatively, such as liver invasion ≥5 mm, invasion of the left margin or the entire area of the hepatoduodenal ligament, and ≥4 regional LNMs. Thus, the five-year overall survival was 54% for zero factors, 34% for one factor, and 4% for two factors (p < 0.05). A poor surgical outcome was likely when two or more factors were predicted preoperatively; therefore, new treatment strategies are required for such patients.

Hepatocellular carcinoma with ring calcification mimicking hydatid disease: a case report

Background

Ring calcification in hepatocellular carcinoma is extremely rare. Untreated hepatocellular carcinoma occasionally includes calcified lesions. Here, we report a case of ring-calcified hepatocellular carcinoma.

Case presentation

A 60-year-old man with a hepatic tumor was referred to Tokyo Women’s Medical University Hospital. He had a history of chronic hepatitis C. Computed tomography showed a liver tumor 20 mm in diameter in segment 6 of the Couinaud classification, with ring calcification. Based on this uncommon imaging presentation and the patient’s past exposure to the definitive hosts of Echinococcus multilocularis, he was preoperatively diagnosed with echinococcosis. Partial hepatectomy was performed as a radical treatment for echinococcosis. A final diagnosis of hepatocellular carcinoma was confirmed based on pathological findings. The patient was discharged uneventfully.

Conclusion

The presentation of an extremely rare hepatocellular carcinoma with ring calcification may be disguised as hydatid disease.

Prognostic Factors for Surgically Resected Intraductal Papillary Neoplasm of the Bile Duct: A Retrospective Cohort Study

BACKGROUND

To date, postoperative prognostic factors for intraductal papillary neoplasm of the bile duct (IPNB) have not been well-established. This study aimed to examine the histopathologic features and postoperative prognosis of the two IPNB subclassifications, as well as factors affecting prognosis, based on the authors' experience at a single institution.

METHODS

The study enrolled 83 patients who underwent surgical resection for pathologically diagnosed IPNB at the authors' institution. The clinicopathologic features and postoperative outcomes for these patients were examined. The study also investigated postoperative prognostic factors for IPNB using uni- and multivariate analyses.

RESULTS

More than half of the tumors (64%) diagnosed as IPNB were early-stage cancer (UICC Tis or T1). However, none were diagnosed as benign. The multivariate analysis showed that lymph node metastasis (hazard ratio [HR], 5.78; p = 0.002) and bile duct margin status with carcinoma in situ (D-CIS; HR, 5.10; p = 0.002) were independent prognostic factors, whereas MUC6 expression showed only a marginal influence on prediction of prognosis (HR, 0.32; p = 0.07). The tumor recurrence rate and the proportion of locoregional recurrence were significantly greater among the patients with D-CIS than among those with negative bile duct margins, including those patients with low-grade dysplasia. The patients with D-CIS showed a significantly poorer prognosis than those with negative bile duct margins (5-year survival, 38% versus 87%; p = 0.0002).

CONCLUSIONS

Evaluation of resected IPNBs showed cancer in all cases. Avoiding positive biliary stumps during surgery, including resection of carcinoma in situ, would improve the prognosis for patients with IPNB.

Comparison of patients with invasive intraductal papillary mucinous carcinoma and invasive ductal carcinoma of the pancreas: a pathological type- and stage-matched analysis

Objective: We compared the pathological features and stage-matched outcomes of patients with invasive intraductal papillary mucinous carcinoma (IPMC) and invasive ductal carcinoma (IDC) of the pancreas to identify the reasons for these diseases' differing prognoses.Methods: We analyzed 114 and 560 patients who underwent curative pancreatectomy for invasive IPMC and IDC, respectively, and analyzed their clinicopathological factors.Results: The disease-specific survival (DSS) of patients with invasive IPMC was significantly superior to that of patients with IDC exhibiting all pathological types at all stages. The DSS of patients with invasive IPMC exhibiting tubular adenocarcinoma was significantly superior to that of their counterparts with IDC only among those with stage IIB (p = .045). When comparing patients with stage IIB tubular adenocarcinoma-type invasive IPMC to their counterparts with IDC, the tumor size (2.6 cm vs. 3.3 cm, p = .010), serum level of carbohydrate antigen 19-9 (253 vs. 474 U/mL, p = .035), number of metastatic lymph nodes (3.1 vs. 4.5, p = .033), vascular invasion rate (14% vs. 41%, p = .0019) and local invasion rate (79% vs. 95%, p = .0045) were lower in the former group. Moreover, the frequency of pathological tubular adenocarcinoma grade 1 was higher in patients with invasive IPMC than in those with IDC (38% vs. 12%, p = .0004) as was the R0 resection rate (90% vs. 65%, p = .0027).Conclusions: In pathological type- and stage-matched analyses, invasive IPMC was associated with a better prognosis than IDC only in patients with stage IIB, as factors governing tumor aggressiveness were milder in the former group than in the latter.

P2691Excimer laser coronary angioplasty can achieve favorable clinical outocomes for in-stent restenosis lesion with neoatherosclerosis

Background

Recent reports revealed that residual area stenosis (% AS) ≤30% after lesion preparation is a suitable predictor for target lesion revascularization (TLR) after drug-coated balloon (DCB) treatment for in-stent restenosis (ISR). Excimer laser coronary angioplasty (ELCA) can obtain larger lumen area and may be more useful for lesion preparation than plain old ballooning (POBA). On the other hands, it has been reported that in-stent neoatherosclerosis (NA) is major cause of restenosis. It is unclear the correlation between NA of ISR and the effect of ELCA. Thus, we compared the influence of NA which was evaluated by optical coherence tomography (OCT) on % AS for ISR treatment between ELCA and DCB (ELCA) group and POBA and DCB (non-ELCA) group and their clinical outcome.

Methods

We enrolled 58 consecutive ISR lesions which were treated by OCT guidance between July 2014 and July 2018 in our hospital. The lesions were divided into NA and non-NA lesions according to OCT findings. In each lesion, we compared post procedural % AS and % AS change which was calculated by the difference between pre and post procedural % AS between ELCA and non-ELCA groups. In addition, we compared 8-month major advance cardiac events (MACE) defined by composite of binary restenosis and target lesion revascularization (TLR) between ELCA and non-ELCA group in NA lesions.

Results

There were 19 NA (33.3%) and 39 non-NA lesions. In NA lesions, ELCA group can obtain significantly lower % AS (p=0.02) and significantly larger % AS change (p<0.01) than non-ELCA group, but in non-NA lesions, % AS and %AS change were similar between ELCA and non-ELCA groups (table). In 8-month clinical outcome, non-ELCA group experienced MACE twice as much as ELCA group did. (31% vs 17%)

Results of %AS NA lesions (n=19) P value non-NA lesions (n=39) P value ELCA group (n=6) non-ELCA group (n=13) ELCA group (n=17) non-ELCA group (n=22) Post %AS (%) 2±21 26±25 0.02 7±29 23±19 0.07 %AS change (%) 71±15 38±19 <0.01 56±29 44±17 0.11

Conclusion

Although neoatherosclerosis is correlated with refractory restenosis, ELCA can improve residual area stenosis in neoatherosclerosis lesions and can achieve better clinical outcomes for in-stent neoatherosclerosis.

P3385Difference of vascular healing after percutaneous coronary intervention between 4 kinds of new generation drug-eluting stents: an optical coherence tomography analysis

Background

New generation drug eluting stents (DES) have improved target vessel failure as compared with early generation DES and bare metal stent. Contemporary several new generation DES are different each other regarding strut thickness and drug and polymer type. A little is known about which stent induces a more favorable vascular healing at follow up.

Purpose

In this study, we compared the vascular healing at 8-month follow up by optical coherence tomography (OCT) between 4 different kinds of new generation DES.

Methods

We enrolled 112 consecutive patients (121 lesions) who underwent PCI using 4 kinds of new generation DES including biodegradable-polymer everolimus-eluting stents (BP-EES), biodegradable-polymer sirolimus-eluting stents (BP-SES), durable-polymer everolimus-eluting stents (DP-EES) and durable-polymer zotarolimus-eluting stents (DP-ZES) and who underwent 8-month follow up angiogram and OCT between July 2016 and April 2018. We compared the OCT parameters including percentage of covered struts, uncovered struts, well-apposed and uncovered struts, malapposed strut and mean neointimal hyperplasia (NIH) thickness between them.

Results

BP-EES consisted of 29 lesions, BP-SES consisted of 25 lesions, DP-EES consisted of 38 lesions and DP-ZES consisted of 29 lesions. A total of 734 frames with 5163 struts in BP-EES, 481 frames with 4214 struts in BP-SES, 783 frames with 6119 struts in DP-EES and 583 frames with 4708 struts in DP-ZES were analyzed. As shown in a table, mean NIH thickness was significantly higher in BP-EES and BP-SES. Thus, we compared the OCT parameters between durable-polymer (DP) group including DP-ZES and DP-EES and biodegradable-polymer (BP) group including BP-EES and BP-SES. The percentage of uncovered struts was significantly lower and mean NIH thickness was significantly higher in BP group than DP group.

Results of OCT parameters BP-EES (n=29) BP-SES (n=25) DP-EES (n=38) DP-ZES (n=29) P value BP group (n=54) DP group (n=67) P value Covered struts (%) 89.5±13.6 92.4±8.6 85.5±17.5 85.0±17.7 0.29 90.9±11.6 85.3±17.4 0.08 Uncovered struts (%) 8.8±10.8 7.1±8.7 14.5±17.5 15.0±17.7 0.14 8.0±9.9 14.7±17.4 0.03 Well-apposed and uncovered struts (%) 7.9±9.9 5.9±7.7 11.7±13.1 12.3±14.0 0.15 7.0±8.9 11.9±13.4 0.04 Malapposed struts (%) 0.8±1.6 1.3±2.2 2.7±5.8 2.7±4.7 0.33 1.0±1.9 2.7±5.3 0.07 Mean NIH thickness (μm) 102±57 121±48 78±28 88±33 <0.01 111±53 82±31 <0.01

Conclusion

The present OCT study demonstrated that delayed neointimal healing characterized by the presence of uncovered struts and lower mean NIH thickness was less common in BP group than DP gruop. Biodegradable-polymer may be more favorable than durable-polymer from the point of view of vascular healing.

103Maximum calcium thickness is a useful predictor for under expansion after post dilatation in calcified lesions: optical coherence tomographic study

Background

Several reports have revealed that stent under expansion is associated with target lesion failure and calcified lesions usually induced inadequate stent expansion. Contemporary debulking devices such as rotational/orbital atherectomy can modify severe calcified lesions before stenting. However, it is uclear which calcium parameter is most useful predictor for stent expansion in the calcified lesions. Thus, we investigated useful calcium parameters correlating with stent expansion in the calcified lesions.

Methods

We enrolled 43 consecutive calcified lesions (43 patients) who underwent optical coherence tomography (OCT) guided percutaneous coronary intervention (PCI) between September 2016 and January 2019. We evaluated the lesions treated with post dilatation by non-compliant balloon due to stent under expansion after stenting. Exclusion criteria included acute coronary syndrome, in-stent restenosis and lesions without any calcium or treated with rotational atherectomy. If there were several calcium lesions in one patient, we selected maximum calcium angle lesion. Stent expansion defined as post-PCI lumen area divided by the values predicted by the manufactures compliance charts. We compared mean reference area, pre lesion area stenosis, calcium parameters including calcium arc, maximum thickness, area and longitudinal length in pre-PCI OCT evaluations with post-PCI stent expansion at that site.

Results

Maximum calcium thickness showed significant correlation with stent expansion, while the others did not show a significant correlation with stent expansion (table). The optimal thresholds of maximum calcium thickness for the prediction of acceptable stent expansion defined by 80% of the values predicted by the manufactures compliance charts was 870mm (area under curve (AUC): 0.65) (figure).

Results of OCT parameters Univariate analysis P value Mean reference area 0.41 Pre % area stenosis 0.16 Calcium parameters   Calcium arc 0.37   Calcium maximum thickness 0.04   Calcium area 0.20   Calcium longitudinal length 0.43

Conclusion

A maximum calcium thickness<870mm is a useful predictor for acceptable stent expansion after post dilatation in calcified lesions.

P3393Comparison of intermediate-term vascular response to new-generation biodegradable polymer and durable polymer-based drug-eluting stents: optical coherence tomographic study

Background

Over the last decade, drug-eluting stents (DES) have undergone substantial modifications with thinner struts and more biocompatible durable polymer (DP) or biodegradable polymer (BP). In DP-based DES, after drug elusion has been completed, DP remnants may trigger of local inflammatory vascular reactions and promote delayed healing, leading to accelerated neoatherosclerosis (NA). Thus, BPs have been developed to reduce the above-mentioned risks. Recently, poor strut coverage and in-stent NA are increasingly recognized the cause of late stent failure, but it is unclear whether BPs can reduce the incidence of NA and the poor stent coverage as compared to DPs.

Objectives

The purpose of this study was to compare the incidence of NA and the stent coverage using optical coherence tomography (OCT) between the DPs and the BPs.

Methods

Between July 2016 and April 2018, 127 consecutive patients with new-generation DES who underwent 8-month follow up OCT imaging were enrolled. Patients were divided into the two groups: DP group who had the new-generation durable polymer everolimus-eluting and zotarolimus-eluting stents and BP group who had the new-generation biodegradable polymer sirolimus-eluting and everolimus-eluting stents. We compared patient characteristics including hypertension, dyslipidemia and diabetes mellitus and 8-month follow up OCT findings including NA, uncovered struts and malapposed struts between the two groups.

Results

The DP group comprised 64 patients (50.4%. The incidence of NA, uncovered struts and malapposed struts were similar between the two groups (DPs vs BPs, 1.56% vs 7.94%, P=0.11; 7.80% vs 5.88%, P=0.16 and 2.76% vs 2.01%, P=0.43, respectively) (table). The other parameters were also similar between the two groups.

Table 1 DP group (n=64) BP group (n=63) P value Hypertension 44 (68.8%) 50 (79.4%) 0.2251 Dyslipidemia 39 (60.9%) 37 (58.7%) 0.8573 Diabetes mellitus 25 (39.1%) 30 (47.6%) 0.3731 8 month OCT follow up findings   Neoatherosclerosis 1 (1.6%) 5 (7.9%) 0.1147   Uncovered struts 7.8% (2.8–20.4) 5.9% (0.7–16.7) 0.1616   Malapposed struts 0.2% (0–2.8) 0% (0–2.8) 0.4392

Conclusions

The new-generation DP based-DES may have similar effects on vascular response compared to the new-generation BP-based DES during 8-month follow-up period.

P2689Irregular protrusion area is associated with incidence of cardiac events after implantation of new generation drug-eluting stents - optical coherence tomography study

Background

Several studies using optical coherence tomography (OCT) have shown that the prevalence of irregular protrusion was associated with the incidence of adverse cardiac events. However, the correlation between cardiac events and protrusion area is not well investigated.

Method

One hundred twenty-nine consecutive patients with 138 clesions with 2nd and 3rd generation drug-eluting stents (DES) which had pre-stenting and post-stenting OCT imaging between April 2016 and April 2018 were evaluated. We compared baseline characteristics, procedure findings and OCT findings including minimum stent area, protrusion type and maximum protrusion area between target lesion revascularization (TLR) group and non-TLR group.

Results

TLR occurred in 12 (9.3%) in 129 patients. The baseline characteristics and procedure findings were similar between TLR group and non-TLR group. Univariate analysis revealed that maximum irregular protrusion area was significantly larger (0.51 [0.00–0.63] vs 0.00 [0.00–0.27], p=0.036) in TLR group than non-TLR group. Receiver operating characteristic curve analysis revealed that the suitable cutoff value of maximum irregular protrusion area were 0.43mm2 for TLR. In multivariate analysis using the parameters with p value<0.10 determined by univariate analysis, maximum irregular protrusion (≥0.43mm2) and minimum stent area (MSA) were independently correlated with TLR (table).

Odd's ratio (95% CI) P value Major irregular protrusion (≥0.43mm2) 17.3 (3.63–82.6) <0.001 MSA 2.13 (1.15–3.93) 0.002

Conclusion

Major irregular protrusion (>0.43mm2) in post-stenting OCT findings may be a powerful predictor of TLR in the patients with new generation DES.

P1736A novel calcium parameter, calcium ratio, can predict minimum lumen area in calcified lesions: optical coherence tomographic study

Background

Several reports have revealed that minimum lumen area (MLA) is associated with target lesion failure even with newer-generation drug-eluting stents, and calcified lesions usually induced inadequate lumen area because of stent under expansion. Contemporary debulking devices such as rotational/orbital atherectomy can modify severe calcified lesions before stenting. However, there are no optimal criteria to indicate necessity for calcium modification to obtain adequate acute gain. Therefore, we investigated useful calcium parameters correlating with MLA in the calcified lesions after stenting.

Methods

We enrolled 71 consecutive calcified lesions (71 patients) who underwent optical coherence tomography (OCT) guided percutaneous coronary intervention (PCI) between September 2016 and January 2019. Exclusion criteria included acute coronary syndrome, in-stent restenosis and lesions without any calcium or treated with rotational atherectomy. If there were several calcium lesions in one patient, we selected maximum calcium angle lesion. We compared mean reference area, pre lumen area and various calcium parameters including calcium arc, maximum thickness, depth, area, longitudinal length and calcium ratio that was maximum calcium thickness divided by nearest reference diameter in disease-free segments as much as possible in pre-PCI OCT evaluation with post-PCI lumen area at that site by simple and multiple regression analysis.

Results

Calcium ratio was an independent predictor for post-PCI lumen area in addition to mean reference area, while the others were not associated with post-PCI lumen area (table).

Results of OCT parameters Univariate analysis Multivariate analysis P value P value β Mean reference area <0.01 <0.01 0.69 Pre lumen area <0.01 0.08 0.15 Cacium arc <0.01 0.58 −0.06 Calcium maximum thickness 0.62 Calcium ratio <0.01 0.01 −0.21 Calcium area 0.02 0.64 0.05 Calcium longitudinal length 0.60 Calcium depth 0.09

Conclusion

The novel calcium measurement, calcium ratio, may be a useful predictor for post-PCI lumen area for calcified lesions.

Abstract P4-02-05: Apocrine morphology and LAR molecular subtype predict prognosis of TNBC patients with residual disease after neoadjuvant chemotherapy

Background: TNBC molecular subtype classification updated by Lehmann et al. includes 4 subtypes: basal-like 1 and 2 (BL1), (BL2), mesenchymal (M), and luminal androgen receptor (LAR), and as a modifier of these subtypes, an Immunomodulatory (IM) gene expression signature. However, molecular subtypes have not been linked to morphological features of TNBC. Apocrine carcinoma has been proposed as a TNBC category that expresses androgen receptor. LAR-subtype TNBC has a poor response to neoadjuvant systemic therapy (NST). We hypothesized that defining the apocrine-featured TNBC by morphology and molecular subtype predict the prognosis of patients with residual disease after NST. Methods: We created the Pan-Pacific TNBC Consortium dataset, which contains paired samples of matched pre and post-NST TNBC tumors from 4 institutions. All patients received NST and didn't have a pathological complete response (pCR). Three pathologists examined hematoxylin and eosin-stained slides of 86 pre-NST samples and determined (1) the presence of apocrine differentiation, (2) the level of tumor-infiltrating lymphocytes (TILs), (3) the histological grade (HG), and (4) the rate of necrosis. These morphological features were compared among the subtypes. For a sample to be considered apocrine positive, apocrine differentiation had to be identified by 2 or more pathologists. Fisher's exact test was used to test the association of subtypes and morphological features. The log-rank test was used to compare disease-free survival (DFS). Results: Twelve of 24 (50%) apocrine-positive tumor samples were LAR subtype, and12 of 17 (70%) LAR-subtype tumor samples exhibited apocrine differentiation. The other subtypes showed following: BL1, 11/44 (25%); BL2, 0/7 (0%); M, 1/10 (10%); unclassified, 0/8 (0%). The median follow-up time was 22 months. In all populations, 2-year DFS rates were higher in patients with apocrine-positive tumors than in those whose tumors did not exhibit apocrine differentiation (P = .027; 2-year DFS, 85% vs 54%). The LAR subtype was also associated with lower HG, although LAR tumors had a similar prognosis to the other subtypes. In the combined analysis of subtypes and apocrine differentiation, patients with apocrine-positive LAR tumors had a higher 2-year DFS rate than did those with apocrine-negative LAR tumors (P = .044; 2-year DFS, 88% vs. 30%). However, patients with apocrine-positive BL1 tumors had no better DFS than did those with apocrine-negative BL1 tumors (P = .133). TIL levels and the presence of the IM signature were positively associated (P = .01), and apocrine differentiation positivity tended to be negatively associated with TIL level (P = .06). Neither TIL level nor IM signature was associated with survival. Conclusion: Apocrine differentiation was associated with the LAR subtype of TNBC and better prognosis in patients who did not have a pCR. The LAR subtype alone did not predict DFS; however, LAR tumors with apocrine differentiation had a better prognosis than did LAR tumors without apocrine differentiation. Using a combination of morphologic and genomic testing may be helpful in determining the prognosis of patients with apocrine-positive TNBC tumors who have residual disease after NST.

Citation Format: Masuda H, Miura S, Harano K, Wang Y, Hirota Y, Matsunaga Y, Lim B, Lucci A, Parinyanitikul N, Lee HJ, Gong G, Rao A, Seitz RS, Morris SW, Hout DR, Nakamura S, Tripathy D, Harada O, Krishnamurthy S, Ueno NT. Apocrine morphology and LAR molecular subtype predict prognosis of TNBC patients with residual disease after neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-02-05.

A long-term recurrence-free survival of a patient with the mixed adeno-neuroendocrine bile duct carcinoma: A case report and review of the literature

INTRODUCTION

Neuroendocrine tumors arising primarily in the bile duct are rare. And among these tumors, mixed adeno-neuroendocrine carcinoma (MANEC) is quite uncommon. We report a patient with MANEC who achieved long-term recurrence-free survival. And our case report includes analysis previous case reports.

PRESENTATION OF CASE

A 66-year-old man underwent investigation for persistent anorexia and fatigue. Laboratory tests showed that the values of hepatobiliary enzymes were increased. On CT, a 10mm×8mm hypervascular tumor was observed in the distal bile duct and the proximal bile duct was markedly dilated. Endoscopic retrograde cholangiography (ERC) also showed a stenosis with a long diameter of 10mm. Examination of a biopsy specimen obtained from the narrow site of the bile duct at the time of ERC revealed tubular adenocarcinoma. Therefore, pylorus-preserving pancreaticoduodenectomy was performed under a preoperative diagnosis of distal bile duct carcinoma. Postoperative pathologic examination revealed alveolar structures and a mixture of moderately differentiated adenocarcinoma with synaptophysin-positive and chromogranin-A-positive neuroendocrine carcinoma. Therefore, the final diagnosis was MANEC, pT3, pN1, M0, pStage II B (TNM classification of the UICC). Curative resection was achieved and there has been no recurrence after 30 months.

DISCUSSION

In the previous reports, only five patients (14.7%) survived for 24 months or longer. Median survival was longer (14 months) in the curative resection group and shorter (6 months) in the non-curative resection group.

CONCLUSION

Curative resection is essential to achieve long-term survival in patients with bile duct MANEC, even if these patients have lymph node metastasis.

Efecto de las condiciones de procesamiento, contenido de grasa y grado de frescura de la materia prima en la calidad de filetes de bagre ahumados / Effect of processing conditions, lipids content and freshness on acceptability of smoked catfish

This work has evaluated the effect of processing conditions on the acceptance of smoked catfish (P. fasciatum). The processing variables studied were thickness (1.9 and 3.6 cm), salting time (30, 60 and 90 min) and smoking time (4, 5 and 6 h at varying temperatures). The influence of the species (P. pirinampu and P. fasciatum) and the freshness of the fillets were also studied. Smoked fillets of 1.9 cm thickness had moisture contents significantly (p < 0.05) lower and the salt concentration was significantly greater than in the salted smoked fillets of 3.6 cm thickness. The thinner fillets received the greatest scores for texture and appearance. Concerning salting time, fillets salted for 30 min received the greatest score for overall acceptance. The greatest dehydration rate ocurred during the first 3 h of smoking at temperatures between 30 and 50°C. Color and texture of products with 5 h and 6 h of smoking were better than those with only 4 h. Lipids content greatly affected sensorial acceptance of smoked products; fillets from P. pirinampu, a fatty fish, received the lowest score for all the sensory attributes evaluated. The loss of freshness of raw fish affected negatively the odor, appearance and overall acceptance of the products.

Acotiamide Hydrochloride, a Therapeutic Agent for Functional Dyspepsia, Enhances Acetylcholine-induced Contraction via Inhibition of Acetylcholinesterase Activity in Circular Muscle Strips of Guinea Pig Stomach

Acotiamide is a first-in-class prokinetic drug approved in Japan for the treatment of functional dyspepsia. Given that acotiamide enhances gastric motility in conscious dogs and rats, we assessed the in vitro effects of this drug on the contraction of guinea pig stomach strips and on acetylcholinesterase (AChE) activity in stomach homogenate following fundus removal. We also investigated the serotonin 5-HT4 receptor agonist mosapride, dopamine D2 receptor and AChE inhibitor itopride, and representative AChE inhibitor neostigmine. Acotiamide (0.3 and 1 μM) and itopride (1 and 3 μM) significantly enhanced the contraction of gastric body strips induced by electrical field stimulation (EFS), but mosapride (1 and 10 μM) did not. Acotiamide and itopride significantly enhanced the contraction of gastric body and antrum strips induced by acetylcholine (ACh), but not that induced by carbachol (CCh). Neostigmine also significantly enhanced the contraction of gastric body strips induced by ACh, but not that by CCh. In contrast, mosapride failed to enhance contractions induced by either ACh or CCh in gastric antrum strips. Acotiamide exerted mixed inhibition of AChE, and the percentage inhibition of acotiamide (100 μM) against AChE activity was markedly reduced after the reaction mixture was dialyzed. In contrast, itopride exerted noncompetitive inhibition on AChE activity. These results indicate that acotiamide enhances ACh-dependent contraction in gastric strips of guinea pigs via the inhibition of AChE activity, and that it exerts mixed and reversible inhibition of AChE derived from guinea pig stomach.

Survey of volume CT dose index in Japan in 2014

OBJECTIVE

The aims of this study are to propose a new set of Japanese diagnostic reference levels (DRLs) for 2014 and to study the impact of tube voltage and the type of reconstruction algorithm on patient doses. The volume CT dose index (CTDI(vol)) for adult and paediatric patients is assessed and compared with the results of a 2011 national survey and data from other countries.

METHODS

Scanning procedures for the head (non-helical and helical), chest and upper abdomen were examined for adults and 5-year-old children. A questionnaire concerning the following items was sent to 3000 facilities: tube voltage, use of reconstruction algorithms and displayed CTDI(vol).

RESULTS

The mean CTDI(vol) values for paediatric examinations using voltages ranging from 80 to 100 kV were significantly lower than those for paediatric examinations using 120 kV. For adult examinations, the use of iterative reconstruction algorithms significantly reduced the mean CTDI(vol) values compared with the use of filtered back projection. Paediatric chest and abdominal scans showed slightly higher mean CTDI(vol) values in 2014 than in 2011. The proposed DRLs for adult head and abdominal scans were higher than those reported in other countries.

CONCLUSION

The results imply that further optimization of CT examination protocols is required for adult head and abdominal scans as well as paediatric chest and abdominal scans.

ADVANCES IN KNOWLEDGE

Low-tube-voltage CT may be useful for reducing radiation doses in paediatric patients. The mean CTDI(vol) values for paediatric scans showed little difference that could be attributed to the choice of reconstruction algorithm.

[A case of liver metastasis from sigmoid colon cancer treated effectively by second-line chemotherapy]

A case of successful chemotherapy for a metachronous liver metastasis following resection for sigmoid colon cancer is presented. A 51-year-old man underwent sigmoidectomy, ileocecal resection, and descending colon colostomy for sigmoid colon cancer with ileum invasion. Six courses of FOLFOX4 were performed as adjuvant chemotherapy. One year after sigmoidectomy, a liver metastasis was detected on computed tomography (CT) examination. Chemotherapy with FOLFOX+bevacizumab was restarted. Three courses were administered, but hepatic dysfunction occurred after the second and third courses, and FOLFOX was discontinued. Subsequent chemotherapy was reinitiated with FOLFIRI+bevacizumab. After 9 courses, the carcinoembryonic antigen level was normalized and appeared to be decreased by imaging studies. Upon the patient's request, only oral S-1 was administered. After 2 courses, CT revealed that the diameter of the tumor had increased by 2 cm. Therefore, right lobectomy of the liver, colostomy closure, and anastomosis were performed. During these procedures, a nodule was found in the omentum and was removed. Rapid intra-operative diagnosis revealed peritoneal dissemination. The pathological diagnosis was liver metastasis of sigmoid colon cancer, with necrosis and fibrosis seen in approximately one-half of specimens. The surgical margins were negative. Neither metastatic cancer nor dissemination were found in the resected greater omentum.

Acotiamide, a new orally active acetylcholinesterase inhibitor, stimulates gastrointestinal motor activity in conscious dogs

BACKGROUND Acotiamide hydrochloride (acotiamide), a novel selective acetylcholinesterase (AChE) inhibitor, has proven significantly effective in treating functional dyspepsia (FD) in clinical trials, particularly in alleviating meal-related symptoms. In the present study, we examined the gastrointestinal prokinetic effects of acotiamide administered orally or intraduodenally in conscious dogs and investigated in vivo and ex vivo anti-AChE activity of acotiamide to clarify its mechanism of prokinetic action.

METHODS

Gastrointestinal motility was measured in conscious dogs with chronically implanted force transducers.

KEY RESULTS

Oral administration of acotiamide stimulated postprandial gastroduodenal and colonic motor activities. Measurement of gastrointestinal motility showed that acotiamide, like itopride and mosapride, enhanced gastric antral motility. Further, acotiamide markedly improved clonidine (an α(2) -adrenoceptor agonist)-induced hypomotility in a dog model of gastric motor dysfunction. The postprandial gastric antral motility enhanced by acotiamide was completely abolished on treatment with the muscarinic receptor antagonist atropine. Results of an in vivo experiment on anti-AChE activity showed clearly increased acetylcholine-induced gastric motility on intraduodenal administration of acotiamide, just as observed with the AChE inhibitor neostigmine. Further, in ex vivo experiment, intraduodenal administration of acotiamide significantly inhibited AChE activity in canine gastric antrum.

CONCLUSIONS & INFERENCES

Our findings revealed that acotiamide administered through the alimentary tract exerts gastroprokinetic action via cholinergic pathways by inhibiting AChE activity. These results may also confirm the mechanism of action in clinical efficacy of acotiamide on FD.

Effects of 8-residue β sheet breaker peptides on aged Aβ40-induced memory impairment and Aβ40 expression in rat brain and serum following intraamygdaloid injection

Amyloidβ-protein (Aβ) assembly into toxic fibrillar structures is seminal in development of senile plaques, the pathological hallmark of Alzheimer's disease. Blocking this process could have a therapeutic value. β-sheet breaker peptides (βSBP) decrease Aβ fibrillogenesis and neurotoxicity by preventing or dissolving misfolded Aβ aggregates. The present study investigated the effects of βSBPs on Aβ40-related neuropathology, memory impairment in 8-armed radial maze and expression of Aβ40 in brain and serum. Aβ40 was injected into amygdaloid nucleus followed 8 days later by octapeptideβSBPs 15-22, 16-23 and 17-24. Aβ40 was detected not only in amygdala, but also in serum. Aβ40 induced cellular changes in amygdala and additionally in hippocampus. Aβ40 decreased correct choices, whereas increased errors (both number of arms revisited and total number of revisits) and latency of completing the maze test. The βSBPs decreased Aβ40-induced pathological changes, memory impairment and Aβ40 expression in serum. The βSBP15-22 distinctively decreased the total errors on day 14. The present results show that octapeptide βSBPs corrected Aβ40-induced memory impairment, and support investigation of βSBPs as a promising treatment of diseases characterized by neurodegeneration and memory impairment such as Alzheimer's disease.

Generation of dendritic cells and macrophages from human induced pluripotent stem cells aiming at cell therapy

This report describes generation of dendritic cells (DCs) and macrophages from human induced pluripotent stem (iPS) cells. iPS cell-derived DC (iPS-DC) exhibited the morphology of typical DC and function of T-cell stimulation and antigen presentation. iPS-DC loaded with cytomegalovirus (CMV) peptide induced vigorous expansion of CMV-specific autologous CD8+ T cells. Macrophages (iPS-MP) with activity of zymosan phagocytosis and C5a-induced chemotaxis were also generated from iPS cells. Genetically modified iPS-MPs were generated by the introduction of expression vectors into undifferentiated iPS cells, isolation of transfectant iPS cell clone and subsequent differentiation. By this procedure, we generated iPS-MP expressing a membrane-bound form of single chain antibody (scFv) specific to amyloid β (Aβ), the causal protein of Alzheimer's disease. The scFv-transfectant iPS-MP exhibited efficient Aβ-specific phagocytosis activity. iPS-MP expressing CD20-specific scFv engulfed and killed BALL-1 B-cell leukemia cells. Anti-BALL-1 effect of iPS-MP in vivo was demonstrated in a xeno-transplantation model using severe combined immunodeficient mice. In addition, we established a xeno-free culture protocol to generate iPS-DC and iPS-MP. Collectively, we demonstrated the possibility of application of iPS-DC and macrophages to cell therapy.

Plasmin induces degradation and dysfunction of laminin 332 (laminin 5) and impaired assembly of basement membrane at the dermal-epidermal junction

BACKGROUND

The epidermal basement membrane (BM), located at the dermal-epidermal junction (DEJ), plays important roles not only in adhesion between epidermis and dermis, but also in controlling skin functions. In sun-exposed skin, the BM becomes disrupted and multilayered. In order to explore the impairment of BM assembly, we have used a skin-equivalent (SE) as a model of BM damage and previously clarified the involvement of matrix metalloproteinases (MMPs) in impairment of BM assembly.

OBJECTIVES

In this work, we examined the role of urokinase-type plasminogen activator (uPA) and plasmin in impairment of BM assembly at the DEJ by using the SE, as ultraviolet irradiation to the skin increases uPA as well as MMPs.

METHODS

SEs were used as a model of formation and damage of BM. Human uPA was detected by enzyme-linked immunosorbent assay and zymography, and gelatinases such as MMP-2 and MMP-9 were detected by zymography. Human plasminogen was added at 0.06 micromol L(-1) (about 3% of plasma level) to increase plasmin to a pathological level. N-terminal peptide sequence analysis of plasmin-treated laminin 332 was carried out to identify alpha3, beta3 and gamma2 chains of laminin 332 and their cleavage sites of each chain. Plasmin-treated laminin 332 was analysed in keratinocyte adhesion activity and binding to type VII collagen.

RESULTS

Human uPA was detected in addition to MMP-2 and MMP-9, in conditioned medium of SE. Although the BM was well organized in the presence of an MMP inhibitor alone, the activated plasmin disorganized the BM even in the presence of the inhibitor. The impairment of BM assembly made the epidermis thinner as compared with that of a control cultured in the presence of MMP inhibitor, indicating that the BM affects the polarity and differentiation of the epidermis. The addition of aprotinin, a serine proteinase inhibitor, and tranexamic acid, a uPA-plasmin inhibitor, inhibited the plasmin-induced impairment of BM assembly and facilitated BM reorganization, thereby improving the epidermal structure. N-terminal peptide sequence analysis of plasmin-treated laminin 332 revealed the removal of a 5- or 10-kDa fragment, including the cell adhesion region, from the G3 domain of the alpha3 chain, and the LN domain, which binds to the noncollagenous 1 domain in type VII collagen, from the beta3 chain. Plasmin-treated laminin 332 showed lower keratinocyte adhesion activity and reduced binding to type VII collagen.

CONCLUSIONS

These results suggest that uPA and plasmin are involved in the impairment of BM assembly and epidermal differentiation, and that these effects arise at least partly through direct degradation of laminin 332.

Specific reactivity of mild/severe Alzheimer's disease patient's sera to antibody against Abeta1-40 epitope 17-21

OBJECTIVES

To detect the reactivity pattern of sera from patients with mild and severe Alzheimer's disease (AD) to specific antibodies targeting different epitopes in the primary structure of amyloid-beta (Abeta).

MATERIALS AND METHODS

Sera from patients diagnosed with mild or severe AD were used. The reactivity of sera to monoclonal antibodies recognizing 1-7, 5-10, 9-14 and 17-21 epitopes of Abeta1-40 at 36-42 degrees C was determined by an enzyme-linked immunosorbent assay. Proteinase K digestion of Abeta1-40 was investigated by dot blotting at 36 and 40 degrees C.

RESULTS

Sera of patients with AD displayed reactivity only with monoclonal antibody recognizing the epitope 17-21 (4G8). The reactivity of sera from patients with severe AD was less than that of sera from patients with mild AD at temperatures 36-41 degrees C, with no difference at 42 degrees C. Patients with severe AD displayed lesser digestion with proteinase K.

CONCLUSIONS

Sera derived from patients with AD could react with monoclonal antibodies directed to 17-21 sequences of Abeta1-40 in a temperature-dependent manner. The severity of AD is associated with greater Abeta1-40 aggregation and resistance to proteinase K. The present results may be of value in staging and following up of patients with AD.