[Validation of Quantitative Accuracy and Variability in 177Lu Imaging Using Monte Carlo Simulation]

PURPOSE

To predict side effects and optimize injection doses in the dosimetry of 177Lu imaging, highly accurate quantitative SPECT images are required. Monte Carlo simulations were performed to verify the accuracy and variability of quantitative values for 177Lu imaging under various imaging conditions.

METHOD

SPECT data of NEMA body phantom were assumed to simulate intrahepatic tumors 6 h after administration of 7.4 GBq of 177Lu-Dotatate. SPECT data were acquired using the SIMIND program with different combinations of collimators and energy windows. For variability evaluation, 30 SPECT images with Poisson noise were generated for each acquisition time. The relative error was evaluated for accuracy evaluation, and the coefficient of variation was estimated for variability evaluation.

RESULTS

The accuracy of BG quantification was less than 10% relative error. The accuracy of hot sphere quantification was highest with the combination of MEGP and an energy window of 208 keV±10%. However, the accuracy of hot sphere quantification decreased significantly with decreasing hot sphere diameter. Variability varied with imaging conditions and improved with longer acquisition time.

CONCLUSION

Monte Carlo simulations revealed the accuracy and variability of quantitative values for each SPECT imaging condition for 177Lu imaging.

Impact of a new dedicated sheath device for tissue sampling of biliary stricture on pathological diagnostic yield: Retrospective study

Background and study aims Endoscopic transpapillary biliary forceps biopsy (TBFB) is a common method for obtaining specimens from biliary lesions. Its diagnostic yield is unsatisfactory; to overcome this disadvantage, a dedicated sheath has been developed. This study aimed to evaluate the outcomes of conventional TBFB and TBFB with a novel sheath device. Patients and methods Consecutive patients who underwent TBFB between January 2020 and December 2021 were retrospectively evaluated. The rate of obtaining adequate samples, failed attempts at forceps insertion into the bile duct, and sensitivity were compared between the two groups. Results Ninety-two patients who underwent 115 endoscopic retrograde cholangiopancreatographies (76 in the conventional group vs. 39 in the dedicated sheath group) were included. The rates of obtaining adequate samples, failed attempts of the forceps into the bile duct, and sensitivity were 72.4% vs. 89.7% ( P = 0.03), 28.3% vs. 0% ( P < 0.01), and 66.7% vs. 88.9% ( P = 0.02), respectively. Conclusions TBFB with the novel sheath device contributed to improved sensitivity for diagnosis of biliary stricture without insertion of forceps outside the bile duct.

Relationship between blood culture time to positivity, mortality rate, and severity of bacteremia

OBJECTIVES

We investigated the association between patient severity or mortality and time to positivity in bacteremia caused by various pathogens.

PATIENTS AND METHODS

This single-center retrospective study included patients with positive blood culture results.

RESULTS

Longer time to positivity was associated with 30-day mortality for Staphylococcus aureus (221 cases, time to positivity: 17.4 h in the 30-day mortality group vs. 14.1 h in the survival group). Age, chronic kidney disease, cerebrovascular disease, hypertensive drug use, consciousness disorder, and minimal systolic blood pressure were significant predictors of 30-day mortality. For S. aureus, mortality within 30 days was significantly higher when time to positivity was > 24 h (p = 0.04). The time to positivity of Streptococcus pneumoniae, α, β-hemolytic Streptococcus, Enterococcus sp., Enterobacteriaceae, glucose-nonfermenting Gram-negative rods, Candida sp., and anaerobe was not significantly associated with 30-day mortality.

CONCLUSIONS

Among various pathogens, time to positivity > 24 h was associated with 30-day mortality for S. aureus.

Endoscopic ultrasound-guided hepaticogastrostomy versus hepaticogastrostomy with antegrade stenting in patients with unresectable malignant distal biliary obstruction: a propensity score-matched case-control study

BACKGROUND AND AIMS

Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is a rescue procedure when endoscopic retrograde cholangiopancreatography fails. Peritonitis and recurrent biliary obstruction (RBO) are adverse events (AEs) associated with EUS-HGS. Antegrade stenting across a malignant distal biliary obstruction (MDBO) followed by EUS-HGS (EUS-HGAS) creates two biliary drainage routes, potentially reducing peritonitis and prolonging time to RBO (TRBO). We compared the outcomes of the two techniques.

METHODS

Data of consecutive patients with MDBO who underwent attempted EUS-HGS or EUS-HGAS across five institutions from January 2014 to December 2020 were retrospectively analyzed. A matched cohort of the patients was obtained using one-to-one propensity score matching. The primary outcome was TRBO, and secondary outcomes included AEs except for RBO and overall survival (OS).

RESULTS

Among 360 patients, 283 (176 and 107 in the HGS and HGAS groups, respectively) were eligible. The matched cohorts included 81 patients in each group. AEs developed in 10 (12.3%) and 15 (18.5%) patients (p=0.38) in the HGS and HGAS groups, respectively. RBO occurred in 18 and 2 patients in the HGS and HGAS groups, respectively (p<0.001). TRBO was significantly longer in the HGAS group (median 194 vs. 716 days; hazard ratio [HR]=0.050, 95% confidence interval [CI]=0.0066-0.37, p<0.01). However, there was no significant difference in OS between the groups (median 97 vs. 112 days; HR=0.97, 95% CI=0.66-1.4, p=0.88).

CONCLUSIONS

EUS-HGAS extended TRBO compared with EUS-HGS, while AEs, except for RBO and OS, did not differ. The longer TRBO of EUS-HGAS could benefit patients with longer life expectancy.

Gap junction beta-4 accelerates cell cycle progression and metastasis through MET-AKT activation in pancreatic cancer

Despite continuing advances in the development of effective new therapies, including immunotherapies, the prognosis of pancreatic cancer remains extremely poor. Gap junction proteins have become attractive targets for potential cancer therapy. However, the role of gap junction beta-4 (GJB4) protein remains unexplored in pancreatic cancer. Through bioinformatic analyses we discovered pancreatic cancer tissues showed higher levels of GJB4 transcripts compared to normal pancreatic tissues and this had a negative effect on overall survival in patients that had pancreatic cancer. The high expression of nuclear GJB4 was identified as a negative prognostic factor in such patients. Knockdown of GJB4 in cultured pancreatic cancer cells resulted in G0 /G1 arrest followed by decreased cell proliferation and suppression of metastatic potential. The overexpression of GJB4 accelerated cell proliferation, migration, and invasion in a SUIT-2 cell line, whereas MET inhibitor canceled the acceleration. GJB4 suppression with siRNA significantly inhibited tumor growth in a mouse xenograft model. Mechanistically, suppression of GJB4 inhibited MET-AKT activities. Such data suggest that targeting the GJB4-MET axis could represent a promising new therapeutic strategy for pancreatic cancer.

Clinical characterization of patients with gBRCA1/2 mutation-positive unresectable pancreatic cancer: a multicenter prospective study

BACKGROUND

Accumulating evidence has demonstrated platinum-based chemotherapy followed by maintenance therapy with a poly Adenosine diphosphate (ADP)-ribose polymerase inhibitor (olaparib) show benefits in unresectable pancreatic cancer with a germline (g)BRCA1/2 mutation. Evaluation of the germline BRCA1 and BRCA2 mutation is essential for making decisions on a treatment strategy for patients with unresectable pancreatic cancer. However, the detection rates of germline BRCA1 and BRCA2 mutations and efficacy of maintenance with olaparib remain undetermined, prospectively, in Japan.

METHODS & RESULTS

In this prospective analysis, the rate of germline BRCA1 and BRCA2 mutations and efficacy of chemotherapy were analyzed in 136 patients with pancreatic cancer who underwent BRACAnalysis® (85 patients) or FoundationOne® CDx (51 patients) between January 2020 and July 2022. A total of six patients (4.4%) had a germline BRCA1 and BRCA2 mutation. Five patients were treated with modified FOLFIRINOX and one with fluorouracil and oxaliplatin. All patients continued platinum-based chemotherapy for ˃4 months and were subsequently treated with olaparib as a maintenance therapy. The response rate to platinum-based chemotherapy in the germline BRCA1 and BRCA2 mutation-positive group was significantly better than that of the germline BRCA1 and BRCA2 mutation-negative group (66% vs 23%, P = 0.04). All patients harbouring a germline BRCA1 and BRCA2 mutation were able to switch to olaparib. The median progression-free survival using olaparib was 5.7 months (range 3.0-9.2).

CONCLUSIONS

The rate of germline BRCA1 and BRCA2 mutations found in patients with unresectable pancreatic cancer was comparable to those of previous studies.An analysis of germline BRCA1 and BRCA2 mutations has benefits for all patients with unresectable pancreatic cancer with regard to decisions on therapeutic strategies in a clinical practice setting.

Transformation of polar nematic phases in the presence of an electric field

Only a few years have passed since the discovery of polar nematics, and now they are becoming the most actively studied liquid-crystal materials. Despite numerous breakthrough findings made recently, a theoretical systematization is still lacking. In the present paper, we take a step toward systematization. The powerful technique of molecular-statistical physics has been applied to an assembly of polar molecules influenced by electric field. Three polar nematic phases were found to be stable at various conditions: the double-splay ferroelectric nematic N_{F}^{2D} (observed in the lower-temperature range in the absence of or at low electric field), the double-splay antiferroelectric nematic N_{AF} (observed at intermediate temperature in the absence of or at low electric field), and the single-splay ferroelectric nematic N_{F}^{1D} (observed at moderate electric field at any temperature below transition into paraelectric nematic N and in the higher-temperature range (also below N) at low electric field or without it. A paradoxical transition from N_{F}^{1D} to N induced by application of higher electric field has been found and explained. A transformation of the structure of polar nematic phases at the application of electric field has also been investigated by Monte Carlo simulations and experimentally by observation of polarizing optical microscope images. In particular, it has been realized that, at planar anchoring, N_{AF} in the presence of a moderate out-of-plane electric field exhibits twofold splay modulation: antiferroelectric in the plane of the substrate and ferroelectric in the plane normal to the substrate. Several additional subtransitions related to fitting the confined geometry of the cell by the structure of polar phases were detected.

Standardization of preoperative stoma site marking and its utility for preventing stoma leakage: a retrospective study of 519 patients who underwent laparoscopic/robotic rectal cancer surgery

PURPOSE

Stoma site marking is an important preoperative intervention for preventing various stoma-associated complications. In our institution, standardized stoma site marking is routinely performed before rectal cancer surgery with stoma creation, and various stoma-associated factors are recorded in the ostomy-record template. The present study investigated risk factors for stoma leakage.

METHODS

Our stoma site marking is standardized so that it can be performed by non-stoma specialists. To identify risk factors of stoma leakage at 3 months after surgery, various preoperative factors associated with stoma site marking in our ostomy-record template were retrospectively analyzed in 519 patients who underwent rectal cancer surgery with stoma creation from 2015 to 2020.

RESULTS

Stoma leakage was seen in 35 of the 519 patients (6.7%). The distance between the stoma site marking and the umbilicus was less than 60 mm in 27 of the 35 patients (77%) who experienced stoma leakage, so a distance of less than 60 mm was identified as an independent risk factor for stoma leakage. Aside from preoperative factors, stoma leakage was also caused by postoperative skin wrinkles or surgical scars near the stoma site in 8 of 35 patients (23%).

CONCLUSION

Preoperative standardized stoma site marking is necessary to achieve reliable marking that is easy to perform. To reduce the risk of stoma leakage, a distance of 60 mm or more between the stoma site marking and the umbilicus is ideal, and surgeons need to contrive ways to keep surgical scars away from the stoma site.

A Rare Case of Sinonasal Seromucinous Hamartoma Developing from the Nasal Septum

A 45-year-old man presented with a history of chronic left nasal congestion. Nasal endoscopy revealed a pedunculated polypoid mass with glandular epithelium surface on the posterior nasal septum. Computed tomography revealed a 25-mm mass-like growth in the left posterior nasal cavity attached to the nasal septum with a stalk. The patient underwent transnasal endoscopic surgery, and the tumor was removed under a block with safety margin. The final pathological diagnosis was sinonasal seromucinous hamartoma (SH). Sinonasal SH is a rare tumor with only 31 reported cases. Transnasal endoscopic surgery is currently the first-line treatment for sinonasal SH. Differential diagnoses of this lesion include inflammatory polyps, respiratory epithelial adenomatoid hamartoma, and adenocarcinoma. Although SH is a benign tumor, its progression to adenocarcinoma has been reported. Therefore, unilateral posterior nasal tumors must be diagnosed precisely.

Online Adaptive Radiotherapy for Pharyngeal Cancer: Dose-Volume Histogram Analysis between Adapted and Scheduled Plan

PURPOSE/OBJECTIVE(S)

The present study aimed to evaluate whether online adapted plan with artificial intelligence (AI) driven work flow could be used in clinical settings with variable changes of the targets and organs at risk (OARs) for pharyngeal cancer.

MATERIALS/METHODS

Ten patients with pharyngeal cancer who underwent chemoradiotherapy at our institution between January and July 2020 were included for the analysis. All patients had been previously aligned daily with cone-beam computed tomography (CBCT) and treated by O-ring Linac. A simulated treatment was performed on the treatment emulator. Weekly fractions, once in every 4-5 fractions, were simulated in the treatment emulator for each patient using their previous on-treatment CBCTs. The dataset was divided into three groups according to the treatment period (1st-2nd week, 20 CBCTs), middle (3rd-4th week, 20 CBCTs), and late (5th-7th week, 30 CBCTs) period. In the present study, all of reference plan generation in treatment emulator were created on the initial plans of two-step method using 12 equidistant field IMRT. The prescribed dose was 70 Gy in 35 fractions and normalized to the dose of 68.6 Gy (98% dose) to 95% of the planning target volume (PTV). The adaptation process on treatment emulator includes auto-segmentation of daily anatomy, calculation of the dose in scheduled plans using the same monitor units and optimization and calculation of the dose in adapted plan. Dose-volume histogram (DVH) parameters between adapted and scheduled plans in terms of PTV (D98%, D95%, D50% and D2%), spinal cord (Dmax and D1cc), brain stem (Dmax), ipsilateral and contralateral parotid glands (Dmedian and Dmean) were evaluated in each period.

RESULTS

D98% of PTV of adapted plan was significantly higher than that of scheduled plan in early and middle period (p = 0.02 and <0.01, respectively). D95% of PTV of adapted plan was significantly higher than that of scheduled plan in all periods (p<0.01). D2% of PTV of adapted plan was significantly lower than that of scheduled plan in all periods (p = 0.04, 0.04 and 0.02 in each period, respectively). There was not significant difference in D50% of PTV between adapted and scheduled plan in all periods. In terms of OARs, Dmax of spinal cord of adapted plan was significantly lower than that of scheduled plan in all periods (p<0.01). Similarly, D1cc of spinal cord of adapted plan was lower than that of scheduled plan. Dmean of ipsilateral and contralateral parotid glands of adapted plan were lower than those of scheduled plan in the late period (p<0.01 and 0.03, respectively).

CONCLUSION

The present study revealed that adapted plan with AI driven work flow could create dosimetrically better plans for pharyngeal cancer compared to scheduled plan. It was suggested that online adaptive radiotherapy could be necessary to maintain PTV coverage while reducing the dose to OARs in all periods for pharyngeal cancer.

Optimization of endoscopic ultrasound-guided tissue sample acquisition for commercially available comprehensive genome profiling

BACKGROUND AND AIM

Optimal tumor samples are crucial for successful analysis using commercially available comprehensive genomic profiling (CACGP). However, samples acquired by endoscopic ultrasound-guided tissue acquisition (EUS-TA) are occasionally insufficient, and no consensus on the optimal number of needle passes required for CACGP exists. This study aimed to explore the optimal number of needle passes required for EUS-TA to procure an ideal sample fulfilling the prerequisite criteria of CACGPs.

METHODS

Patients who underwent EUS-TA for solid masses between November 2019 and July 2021 were retrospectively studied. The correlation between the acquisition rate of an ideal sample and the number of needle passes mounted on a microscope slide was evaluated. Additionally, the factors predicting a successful analysis were investigated in patients scheduled for CACGP using EUS-TA-obtained samples during the same period.

RESULTS

EUS-TAs using 22- and 19-gauge (G) needles were performed in 336 and 57 patients, respectively. There was a positive correlation between the acquisition rate and the number of passes using a 22-G needle (38.9%, 45.0%, 83.7%, and 100% for 1, 2, 3, and 4 passes, respectively), while no correlation was found with a 19-G needle (84.2%, 83.3%, and 85.0% for 1, 2, and 3 passes, respectively). The analysis success rate in patients with scheduled CACGP was significantly higher with ideal samples than with suboptimal samples (94.1% vs 55.0%, P < 0.01).

CONCLUSIONS

The optimal estimated number of needle passes was 4 and 1-2 for 22- and 19-G needles, respectively.

Cardioprotective effect of empagliflozin in acute myocardial infarction: the role of ketone bodies availability

Background

The cardio-renal benefits of SGLT2i have been clearly established by clinical trials. Of interest, despite not having any effect on the incidence of classic atherothrombotic events (MI and strokes), patients receiving SGLT2i treatment had a higher chance of surviving myocardial infarction (MI).

Purpose

We aim to evaluate the cardioprotective potential of empagliflozin on acute myocardial infarction.

We postulate that the benefits of SGLT2-I are mediated via an increase in circulating ketone bodies (KBs) induced by SGLT2i, and its preferential myocardial utilization energetically benefits the heart to better withstand an ischemic event.

Methods

The study was undertaken in our non-diabetic porcine model of ischemia/reperfusion. Animals were allocated to either one-week pre-treatment with empagliflozin or placebo before MI-induction. A third group received IV infusion of KBs at the time of the MI- induction to serve as positive-control. The acute effects of the treatments were studied 24 hours after MI-induction by Cardiac Magnetic Resonance (CMR). Immediately post-CMR, animals were sacrificed and heart samples collected for molecular analysis.

Results

(see Table and Figure): Despite similar initial ischemic injury (area at risk) in all groups, empagliflozin was associated with a significantly higher myocardial salvage (MSI 23.7±9.7 vs 4.5±3.6%, p&lt;0.001) and better preserved cardiac function (LVEF 41.3±3.1 vs 33±5.5%, p&lt;0.009) compared with placebo. The infusion of KBs replicated in part the beneficial profile of the empagliflozin group (MSI 16.7±8.8 and LVEF 39.1±3.6%). Histological analysis showed less cardiomyocyte apoptosis and less oxidative stress

Conclusions

To the best of our knowledge, this is the first study evaluating in vivo the cardioprotective potential of a SGLT2 inhibitor in a well-stablished porcine translational model. Furthermore, effects are evaluated using the gold standard for visualization and quantification of MI, Cardiac Magnetic Resonance (CMR). Three are the main conclusions:

1. One-week treatment with empagliflozin raises circulating KBs levels and confers significant cardio-protection during a myocardial infarction. Acute post-MI benefits (greater myocardial salvage and better preserved cardiac function) are already seen within 24 hours as compared with placebo.

2. Periprocedural IV infusion of KBs induces similar benefits than the SGLT2-I group.

3. These observations strongly support our hypothesis that SGLT2 inhibition is associated with increased circulating KBs and its selective use as preferential myocardial source of energy as a potential mechanism of action involved in the cardio-renal benefits observed with SGLT2i.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Spanish Society of Cardiology. Research Fellowship Grant.

Emergence of paraelectric, improper antiferroelectric, and proper ferroelectric nematic phases in a liquid crystal composed of polar molecules

We have elaborated a theoretical approach for the description of polar nematic phases observed by Nishikawa et al. [Adv. Mater. 29, 1702354 (2017)0935-964810.1002/adma.201702354], their structures, and transitions between them. Specific symmetry contributions to the pair molecular potentials provide the molecular mechanisms responsible for the formation of proper and improper polarity on the macroscopic level. An improper antiferroelectric nematic M2 phase can arise between paraelectric nematic M1 and proper ferroelectric nematic MP in the temperature scale. The local polarization in M2 arises mostly due to the local splay deformation. The director distribution in M2 represents the conjugation of cylindrical waves with opposite splay and polarization signs. The director and polarization are parallel to the cylindrical domain axes in the middle of each cylinder but exhibit considerable (mostly radial) deformation on the periphery of each cylinder. Polarization vectors are mostly stacked antiparallel on the borders between the domains without the director disruption. The domain size decreases with the decreasing temperature, the percentage of the antiferroelectric decouplings increases, and M2 exhibits the first-order phase transition into proper ferroelectric MP. With the increasing temperature the domain size in the M2 phase increases, the domination of particular polar orientation of molecules reduces, and finally, the domain size diverges at particular temperature corresponding to the second-order phase transition from M2 to paraelectric M1. Variations of the polar and nonpolar orientational order parameters are estimated within each phase and between the phases. Our experimental and computer simulation results (also presented in the paper) fully support our theoretical findings.

Biliary obstruction and pancreatitis after duodenal stent placement in the descending duodenum: a retrospective study

BACKGROUND

Metallic stents placed in the descending duodenum can cause compression of the major duodenal papilla, resulting in biliary obstruction and pancreatitis. These are notable early adverse events of duodenal stent placement; however, they have been rarely examined. This study aimed to assess the incidence of and risk factors for biliary obstruction and/or pancreatitis after duodenal stent placement in the descending duodenum.

METHODS

We retrospectively reviewed data of consecutive patients who underwent metallic stent placement in the descending duodenum for malignant gastric outlet obstruction at a tertiary referral cancer center between April 2014 and December 2019. Risk factors for biliary obstruction and/or pancreatitis were analyzed using a logistic regression model.

RESULTS

Sixty-five patients were included. Biliary obstruction and/or pancreatitis occurred in 12 patients (18%): 8 with biliary obstruction, 2 with pancreatitis, and 2 with both biliary obstruction and pancreatitis. Multivariate analysis indicated that female sex (odds ratio: 9.2, 95% confidence interval: 1.4-58.6, P = 0.02), absence of biliary stents (odds ratio: 12.9, 95% confidence interval: 1.8-90.2, P = 0.01), and tumor invasion to the major duodenal papilla (odds ratio: 25.8, 95% confidence interval: 2.0-340.0, P = 0.01) were significant independent risk factors for biliary obstruction and/or pancreatitis.

CONCLUSIONS

The incidence of biliary obstruction and/or pancreatitis after duodenal stent placement in the descending duodenum was non-negligible. Female sex, absence of biliary stents, and tumor invasion to the major duodenal papilla were the primary risk factors. Risk stratification can allow endoscopists to better identify patients at significant risk and permit detailed informed consent.

Propensity score matching analysis for adverse events of EUS-guided biliary drainage in advanced elderly patients (PEACE study)

BACKGROUND

Several studies have suggested that elderly patients, as well as younger patients, can be safely treated using endoscopic retrograde cholangiopancreatography (ERCP). However, endoscopic ultrasound-guided biliary drainage (EUS-BD) has not been clinically evaluated for very elderly patients. The present multicenter, retrospective study aimed to determine the safety of EUS-BD for advanced elderly patients.

METHOD

Patients who underwent EUS-BD during this period were retrospectively enrolled, and they were divided into two groups based on age: group A (age  < 75 years) and group B (age ⩾ 75). In this study, capnographic monitoring was used only for elderly patients (age ⩾ 75 years).

RESULTS

A total of 271 patients who underwent EUS-BD were enrolled in this study (group A = 177, group B = 94). The types of adverse events that were associated with EUS-BD was observed in 38 patients, and they did not differ significantly between two groups (p = 0.855). This result was confirmed after propensity score matching (p = 0.510). Adverse events were associated with sedation after propensity score matching; hypoxemia (p = 0.012) and severe hypoxemia (p = 0.003) were significantly higher in group A compared with group B. According to logistic regression analysis, monitoring (non-capnography) was also only risk factor (odds ratio: 0.317, 95% confidence interval: 0.143-0.705; p = 0.005) for sedation-related adverse events.

CONCLUSION

In conclusion, EUS-BD could be safety performed in advanced elderly patients, the same as in younger patients. Also, capnographic monitoring might be helpful in case of sedation by a gastroenterologist in a non-intubated patient. Further prospective, randomized studies are needed to confirm these conclusions.

Macroscopic visible core length can predict the histological sample quantity in endoscopic ultrasound-guided tissue acquisition: Multicenter prospective study

OBJECTIVES

Measurement of the macroscopic visible core (MVC) length during macroscopic on-site quality evaluation (MOSE) may allow estimation of sample adequacy for next-generation sequencing (NGS), and prediction of correct diagnosis in endoscopic ultrasound-guided tissue acquisition (EUS-TA) of pancreatic masses.

METHODS

This multicenter prospective study included consecutive patients who underwent EUS-TA for pancreatic masses using a 22-G Franseen needle. MVC length and pathological samples obtained from two needle passes were analyzed on a per-pass basis. Outcome measures included respective correlations of MVC length with histological sample quantity and diagnostic yields.

RESULTS

The analysis included 204 passes from 102 EUS-TAs. MVC length correlated positively with histological sample quantity (P < 0.01). On the receiver operating characteristic curve for MVC length, the cut-off value and area under the curve for obtaining a candidate sample for NGS were 30 mm and 0.74 (95% confidence interval [CI] 0.65-0.83), respectively. On multivariate analysis, MVC length ≥30 mm was a significant factor affecting suitability for NGS (odds ratio 6.19; 95% CI 2.72-14.10). Histologic diagnostic yield correlated positively with MVC length (P = 0.01); however, there was no positive correlation between MVC length and overall (histology plus cytology) diagnostic yield.

CONCLUSIONS

Measuring MVC length to predict histological sample quantity on MOSE may be of clinical significance during EUS-TA using a 22-G Franseen needle. It may be an effective method, particularly while submitting samples for NGS.

REGISTRATION

University Hospital Medical Information Network Trials Registry (UMIN000036528).

Microsatellite instability is biased in Amsterdam II-defined Lynch-related cancer cases with family history but is rare in other cancers: a summary of 1000 analyses

Background

Microsatellite instability (MSI) is a key marker for predicting the response of immune checkpoint inhibitors (ICIs) and for screening Lynch syndrome (LS).

Aim

This study aimed to see the characteristics of cancers with high level of MSI (MSI-H) in genetic medicine and precision medicine.

Methods

This study analyzed the incidence of MSI-H in 1000 cancers and compared according to several clinical and demographic factors.

Results

The incidence of MSI-H was highest in endometrial cancers (26.7%, 20/75), followed by small intestine (20%, 3/15) and colorectal cancers (CRCs)(13.7%, 64/466); the sum of these three cancers (15.6%) was significantly higher than that of other types (2.5%)(P < 0.0001). MSI-H was associated with LS-related cancers (P < 0.0001), younger age (P = 0.009), and family history, but not with smoking, drinking, or serum hepatitis virus markers. In CRC cases, MSI-H was significantly associated with a family history of LS-related cancer (P < 0.0001), Amsterdam II criteria [odds ratio (OR): 5.96], right side CRCs (OR: 4.89), and multiplicity (OR: 3.31). However, MSI-H was very rare in pancreatic (0.6%, 1/162) and biliary cancers (1.6%, 1/64) and was null in 25 familial pancreatic cancers. MSI-H was more recognized in cancers analyzed for genetic counseling (33.3%) than in those for ICI companion diagnostics (3.1%)(P < 0.0001). Even in CRCs, MSI-H was limited to 3.3% when analyzed for drug use.

Conclusions

MSI-H was predominantly recognized in LS-related cancer cases with specific family histories and younger age. MSI-H was limited to a small proportion in precision medicine especially for non-LS-related cancer cases.

Efficacy of endoscopic samplings during initial biliary drainage for cases of pancreatic head cancer: United diagnostic yields of multiple pathological samplings

BACKGROUND/OBJECTIVES

The diagnostic ability of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has been fully studied; however, the efficacy of other endoscopic samplings (OESs) is less clear. The aim of this study was to examine the diagnostic efficacies of OESs for pancreatic head cancer (PHC).

METHODS

The diagnostic efficacies of endoscopic samplings were retrospectively analyzed in 448 PHC cases and 63 cases of mass-forming pancreatitis (MFP) during initial transpapillary biliary drainage. The OESs included duodenal biopsy (118 PHCs and 50 MFPs), biliary biopsy (218 and 51) with cytology (368 and 53), and pancreatic duct biopsy (23 and 13) with cytology (56 and 43). EUS-FNA was conducted in a different session (149 and 62). Factors associated with OES sensitivity were analyzed. The sensitivity of biliary biopsy was compared between 1.95 mm and 1.8 mm forceps.

RESULTS

Cancer cells were confirmed in 87.9% of the EUS-FNA samplings and in 64.1% (268/418) obtained by combined OESs (average 1.7 OES types per case): 68.6% by duodenal biopsy, 59.6% by biliary biopsy, 32.6% by biliary cytology, 73.9% by pancreatic duct biopsy, and 33.9% by pancreatic duct cytology. No MFP cases revealed cancer by any sampling. OESs did not increase adverse events. Duodenal stenosis, serum bilirubin, tumor size, and pancreatic juice amounts were associated with OES sensitivity. Biliary biopsy had the same sensitivity with different forceps.

CONCLUSION

EUS-FNA was the most diagnostic protocol; however, OESs can be safely applied during the initial biliary drainage to reduce the demand for EUS-FNA while providing good diagnostic yields.

[A case of intraductal tubulopapillary adenocarcinoma with bone metastases]

A woman in her 70s with main pancreatic duct dilatation was referred to our hospital. Various imaging examinations showed an extensive mass within the lumen of the main pancreatic duct in the head and body of the pancreas. The microscopic examination of a biopsy specimen revealed an adenocarcinoma. She was diagnosed with intraductal tubulopapillary adenocarcinoma of the pancreas;a pylorus-preserving total pancreatectomy was subsequently performed. However, 30 days after surgery, the patient presented with neck pain and left upper arm numbness. Results of magnetic resonance imaging and bone scintigraphy revealed a cervical spinal tumor that was subsequently biopsied. The patient was diagnosed with intraductal tubulopapillary adenocarcinoma with bone metastasis.

AB0065 HGF/C-MET SIGNALING PROMOTE ANGIOGENESIS THROUGH CXCL16 IN RHEUMATOID ARTHRITIS

Background:

Hepatocyte growth factor (HGF) binds to the receptor tyrosine kinase c-Met and is a multifunctional cytokine that promotes processes such as cell proliferation, survival, differentiation, migration and angiogenesis [1]. We previously reported that HGF is produced by inflammation in the RA synovium, and activates monocyte migration to the synovium and promotes bone destruction through its own chemotactic effect and enhanced chemokine production in the synovium [2].

Objectives:

Therefore, we next aimed to determine the role of HGF in RA angiogenesis.

Methods:

The expression of HGF / c-Met in the serum and synovial tissues (STs) of RA patients and controls and human umbilical vein endothelial cells (HUVECs) was evaluated by ELISA and immunostaining. The effect of HGF/c-Met signaling on the promotion of CXCL16 production from HUVECs and RA fibroblast-like synoviocytes (FLSs) was determined by ELISA. To examine the role of HGF in angiogenesis, we performed in vitro Matrigel assays using HUVECs treated with HGF.

Results:

HGF in serum in treatment-naive RA patients was significantly higher than that in controls and HGF in serum in treatment-resistant RA showed a significant positive correlation with CXCL16. c-Met were expressed on vascular endothelial cells of RA STs and HUVECs. Stimulation of HUVECs with HGF dose-dependently increased CXCL16 production. c-Met signal inhibition by SU11274 suppressed TNF-α stimulation-enhanced CXCL16 production by RA FLSs in a dose-dependent manner. Furthermore, HGF induced HUVEC tube formation by 1.8-fold.

Conclusion:

HGF is produced by inflammation in the RA synovium, and activates angiogenesis through its own potent angiogenic effect and enhanced production of CXCL16 in the synovium. These results indicate that a strategy targeting c-Met signalling may be important for resolving treatment-resistant RA.

References:

[1]Nakamura T, Nishizawa T, Hagiya M, et al. Molecular cloning and expression of human hepatocyte growth factor. Nature. 1989 Nov 23;342(6248):440-3.

[2]Hosonuma M, Sakai N, Furuya H, et al. Inhibition of hepatocyte growth factor/c-Met signalling abrogates joint destruction by suppressing monocyte migration in rheumatoid arthritis. Rheumatology (Oxford). 2021 Jan 5;60(1):408-419.

Disclosure of Interests:

None declared

POS0429 INTERLEUKIN-4 ACTIVATES EOSINOPHILS AND CCR3-POSITIVE T HELPER CELLS MIGRATION TO FASCIA AND PROMOTES FIBROSIS IN EOSINOPHILIC FASCIITIS

Background:

Eosinophilic fasciitis (EF) is a rare disease that causes inflammation and fibrosis mainly in the fascia of the extremities with eosinophilia. It has been reported that the hypertrophied fascia in EF shows inflammatory cell infiltration by the lymphocytes and eosinophils and increased expression of fibrosis-related cytokines genes in fibroblast [1]. However, its pathophysiology in the fascia remains unresolved.

Objectives:

Therefore, we focused on fascial fibroblasts and aimed to determine the role of interleukin-4 (IL-4) in eosinophil and helper T cell infiltration and fibrosis in fascial fibroblast in EF.

Methods:

Fascial fibroblasts were obtained from fascia biopsy of a patient with EF, and were stimulated with pre- and post-treatment serum of a patient with EF and healthy control, followed by microarray to analyze gene expression. Fascial fibroblasts were stimulated with IL-4 10 ng/mL, and gene expression of IL-4 receptor and CCR3 ligands, CCL7 and CCL11 were measured by qPCR. Transforming growth factor (TGF) -β and periostin in the pre- and post-treatment serum of a patient with EF and conditioned medium of fascial fibroblasts stimulated with IL-4 were measured by ELISA. To examine the role of IL-4 in proliferation, we performed in proliferation assays using fascial fibroblasts treated with IL-4. CCR3-positive T cells in the fascial tissue of EF, dermatomyositis, and polymyositis patients were evaluated by immunostaining.

Results:

By microarray analysis, CCL7 and CCL11 expression of fascial fibroblasts stimulated with pre-treatment EF serum was higher than that in post-treatment EF serum and control serum. CCL7 and CCL11 mRNA in IL-4 stimulated facial fibroblasts were increased by 5.1-fold and 7.3-fold, respectively. TGF-β and periostin in IL-4 stimulated facial fibroblast conditioned medium were also increased. In addition, TGF-β and periostin in EF serum were gradually decreased by treatment for 4 and 10 weeks, compared to before treatment. Finally, fascial fibroblast proliferation was significantly increased by stimulation with IL-4. Furthermore, infiltration of CCR3-positive T cells was specific to the fascial tissue of EF.

Conclusion:

In EF, IL-4 enhances the production of CCR3 ligands, TGF-β, and periostin from fascial fibroblasts. As a result, it promotes the migration of eosinophils and CCR3-positive T helper cells to the fascia and fibrosis. These results suggest that inhibition of IL-4 pathway could be a novel strategy for eosinophilic fasciitis.

References:

[1]Igarashi A, Nashiro K, Kikuchi K, et al. Connective tissue growth factor gene expression in tissue sections from localized scleroderma, keloid, and other fibrotic skin disorders. J Invest Dermatol. 1996 Apr;106(4):729-33.

Disclosure of Interests:

None declared

Comparison of five-phase computed tomography images of type 1 autoimmune pancreatitis and pancreatic cancer: Emphasis on cases with atypical images

BACKGROUND/OBJECTIVES

International consensus diagnostic criteria (ICDC) include characteristic images of autoimmune pancreatitis (AIP); however, reports on atypical cases are increasing. The aims of this study were to compare CT findings between AIP and pancreatic cancer (PC), and to analyze type 1 AIPs showing atypical images.

METHODS

Five-phase CT images were compared between 80 type 1-AIP lesions and 80 size- and location-matched PCs in the case-control study. Atypical AIPs were diagnosed based on the four ICDC items.

RESULTS

ICDC items were recognized in most AIP lesions; pancreatic enlargement (87.7%), narrowing of the main pancreatic duct (98.8%), delayed enhancement (100%), and no marked upstream-duct dilation (97.5%). CT values of AIPs increased rapidly until the pancreatic phase and decreased afterward, while those of PCs gradually increased until the delayed phase (P < 0.0001). Atypical images were recognized in 14.8% of AIPs, commonly without pancreatic enlargement (18.5 mm) and sometimes mimicking intraductal neoplasms. The CT values and their ratios were different between atypical AIPs and size-matched PCs most significantly in the pancreatic phase, but similar in the delayed phase.

CONCLUSIONS

Ordinary type 1 AIPs can be diagnosed with the ICDC, but atypical AIPs represented a small fraction. "Delayed enhancement" is characteristic to ordinary AIPs, however, "pancreatic-phase enhancement" is more diagnostic for atypical AIPs.

Type 1 Autoimmune Pancreatitis Extending along the Main Pancreatic Duct: IgG4-related Pancreatic Periductitis

We herein report a unique form of autoimmune pancreatitis (AIP) spreading along the main pancreatic duct (MPD). A 70-year-old man was referred for a small lesion at the pancreatic neck, accompanying an adjacent cyst and dilated upstream MPD. Four years earlier, health checkup images had shown a pancreatic cyst but no mass lesion. Endoscopic ultrasonography showed a contrast-enhanced, tumorous lesion, mainly occupying the MPD. With a preoperative diagnosis of ductal neoplasms mainly spreading in the MPD, Whipple's resection was performed. The resected specimens showed MPD periductitis with IgG4-related pathology, indicating type 1 AIP. Clinicians should practice caution concerning the various AIP forms.

A case of hypervascular tumors in the liver and pancreas: synchronous hepatocellular carcinoma and pancreatic metastasis from renal cell carcinoma 36 years after nephrectomy

It is sometimes difficult to distinguish between multiple cancers and metastases using only diagnostic imaging, particularly when multiple hypervascular tumors are found in multiple organs. We present a case in which the preoperative histological evaluation was essential to determine the management of a hypervascular pancreatic tumor and liver tumor.

The effects of wheel-running using the upper limbs following immobilization after inducing arthritis in the knees of rats

This study investigated the effects of wheel-running using the upper limbs following immobilization after inducing arthritis in the knees of rats. Forty male Wistar rats (aged 8 weeks) divided into four groups randomly: arthritis (AR), immobilization after arthritis (Im), wheel-running exercise with the upper limbs following immobilization after arthritis induction (Im+Ex) and sham arthritis induction (Con). The knee joints of the Im and Im+Ex groups were immobilized with a cast for 4 weeks. In the Im+Ex group, wheel-running exercise was administered for 60 min/day (5 times/week). The swelling and the pressure pain threshold (PPT) of the knee joint were evaluated for observing the condition of inflammatory symptoms in affected area, and the paw withdraw response (PWR) was evaluated for observing the condition of secondary hyperalgesia in distant area. Especially, in order to evaluate histological inflammation in the knee joint, the number of macrophage (CD68-positive cells) in the synovium was examined. The expression of calcitonin gene-related peptide (CGRP) in the spinal dorsal horn (L2-3 and L4-5) was examined to evaluate central sensitization. The Im+Ex group showed a significantly better recovery than the Im group in the swelling, PPTs, and PWRs. Additionally, CGRP expression of the spinal dorsal horn (L2-3 and L4-5) in the Im+Ex group was significantly decreased compared with the Im group. According to the results, upper limb exercise can decrease pain in the affected area, reduce hyperalgesia in distant areas, and suppress the central sensitization in the spinal dorsal horn by triggering exercise-induced hypoalgesia (EIH).

Long-term outcomes and recurrence-free interval after the treatment of keloids with a standardized protocol

BACKGROUND

Recurrence rates of keloids have generally been reported at one time point. However, the longer the duration after treatment, the greater the likelihood that such lesions will recur. In this study, we analysed the time to recurrence during long-term follow-up.

MATERIAL AND METHODS

We retrospectively reviewed recurrence-free interval in 52 patients with keloid (age 8-79 years) who had been treated between June 2006 and January 2011 using a standardised protocol developed by our group.

RESULTS

Mean duration of follow-up was 37.5 (range, 7-120) months in patients with keloid. Kaplan-Meier survival curves revealed a statistically significant difference in recurrence-free interval between ear keloids and keloids excluding ear keloids. Recurrence rate for keloids was high in the first 2 years after treatment.

CONCLUSIONS

Kaplan-Meier analysis was useful for understanding the tendency of recurrence of keloids after treatment using a standardised protocol.

Short-term risk stratification using CADILLAC risk score in patients with ST elevation myocardial infarction

Background

The recent reperfusion therapy for ST-elevation myocardial infarction (STEMI) has made the length of hospital stay shorter without adverse events. CADILLAC risk score is reportedly one of the risk scores predicting the long-term prognosis in STEMI patients.

Purpose

To invenstigate the usefulness of CADILLAC risk score for predicting short-term outcomes in STEMI patients.

Methods

Consecutive patients admitted to our university hospital and our medical center with STEMI (excluding shock, arrest case) who underwent primary PCI between January 2012 and April 2018 (n=387) were enrolled in this study. The patients were classified into 3 groups according to the CADILLAC risk score: low risk (n=176), intermediate risk (n=87), and high risk (n=124). Data on adverse events within 30 days after hospitalization, including in-hospital death, sustained ventricular arrhythmia, recurrent myocardial infarction, heart failure requiring intravenous treatment, stroke, or clinical hemorrhage, were collected.

Results

In the low risk group, adverse events within 30 days were significantly less observed, compared to the intermediate and high risk groups (n=13, 7.4% vs. n=13, 14.9% vs. n=58, 46.8%, p&lt;0.001). In particular, all adverse events occurred within 3 days in the low risk group, although adverse events, such as heart failure (n=4), recurrent myocardial infarction (n=1), stroke (n=1), and gastrointestinal bleeding (n=1), were substantially observed after day 4 of hospitalization in the intermediate and high risk groups.

Conclusions

In STEMI patients with low CADILLAC risk score, better short-term prognosis was observed compared to the intermediate and high risk groups, and all adverse events occurred within 3 days of hospitalization, suggesting that discharge at day 4 might be safe in this study population. CADILLAC risk score may help stratify patient risk for short-term prognosis and adjust management of STEMI patients.

Initial event occurrence timing

Funding Acknowledgement

Type of funding source: None

Rare case of acinar cell carcinoma with multiple lesions in the pancreas

We present the first case of pancreatic acinar cell carcinoma (PACC) with multiple lesions. A 55‐year‐old man with a pancretic tail mass on abdominal computed tomography (CT) was admitted to our hospital. Endoscopic ultrasound (EUS) showed a hypoechoic mass, and EUS‐guided fine‐needle aspiration (EUS‐FNA) revealed the mass to be PACC. The patient underwent distal pancreatectomy, and two masses were identified in the pancreatic tail and body. Histologically, both masses had tumor cells similar to acinar cells and were positive for BCL‐10. The patient was thus diagnosed with synchronous PACC. Ten months after the surgery, abdominal CT revealed a mass in the remnant pancreas. EUS showed a hypoechoic mass, and EUS‐FNA determined it to be PACC. The patient underwent total remnant pancreatectomy. The histological imaging results were similar to those of the first resection. Finally, the patient was diagnosed with synchronous and metachronous PACC. The possibility of multiple occurrences in the pancreas should be considered with PACC.

Efficacy of combination therapy with dexmedetomidine for benzodiazepines-induced disinhibition during endoscopic retrograde cholangiopancreatography

BACKGROUND

Benzodiazepines (BZDs) and analgesics are widely used for conscious sedation during endoscopic ultrasound (EUS) or endoscopic retrograde cholangiopancreatography (ERCP). However, endoscopic procedures are sometimes discontinued because of BZD-induced disinhibitory reactions such as excessive movement. We evaluated the usefulness of dexmedetomidine (DEX) for BZD-induced disinhibition in ERCP.

METHODS

Between February 2018 and August 2019, 22 patients who underwent EUS or ERCP were enrolled. All patients showed BZD-induced excessive movement at the first examination (BZD group) and received DEX at the second examination (DEX group). The initial DEX dose was 6 μg/kg/h for a 10-min loading, followed by 0.4 μg/kg/h during the procedure. BZDs and analgesics were administered before scope insertion. An additional sedative was administered to achieve a Ramsay sedation scale (RSS) of 4-5. Sedative effect, procedure completion rate, and changes in circulatory and respiratory dynamics were evaluated.

RESULTS

Mean RSS scores were significantly higher (p < 0.001) in the DEX (5.1 ± 0.5) compared with the BZD (4.0 ± 0.5) group. The movement score (p < 0.001) and number of additional sedatives required (p < 0.01) were lower in the DEX group. The procedure completion rate was significantly higher in the DEX (95.5%) compared with the BZD group (63.6%; p < 0.05). Significant differences in the frequency of hypotension (p = 1.00), bradycardia (p = 0.22), and respiratory depression (p = 0.68) were not noted between groups.

CONCLUSIONS

The addition of DEX to BZD therapy yielded better sedative efficacy, lower excessive movement, a reduction in BZDs used, and a higher procedure complete rate. DEX may be used as an alternative method for BZD-induced inhibition during ERCP.

Serum immunoglobulin G antibody titer to Fusobacterium nucleatum is associated with unfavorable outcome after stroke

Stroke can be a cause of death, while in non-fatal cases it is a common cause of various disabilities resulting from associated brain damage. However, whether a specific periodontal pathogen is associated with increased risk of unfavorable outcome after stroke remains unknown. We examined risk factors for unfavorable outcome following stroke occurrence, including serum antibody titers to periodontal pathogens. The enrolled cohort included 534 patients who had experienced an acute stroke, who were divided into favorable (n = 337) and unfavorable (n = 197) outcome groups according to modified ranking scale (mRS) score determined at 3 months after onset (favorable = score 0 or 1; unfavorable = score 2-6). The associations of risk factors with unfavorable outcome, including serum titers of IgG antibodies to 16 periodontal pathogens, were examined. Logistic regression analysis showed that the initial National Institutes of Health stroke scale score [odds ratio (OR) = 1·24, 95% confidence interval (CI) = 1·18-1·31, P < 0·001] and C-reactive protein (OR = 1·29, 95% CI = 1·10-1·51, P = 0·002) were independently associated with unfavorable outcome after stroke. Following adjustment with those, detection of the antibody for Fusobacterium nucleatum ATCC 10953 in serum remained an independent predictor of unfavorable outcome (OR = 3·12, 95% CI = 1·55-6·29, P = 0·002). Determination of the antibody titer to F. nucleatum ATCC 10953 in serum may be useful as a predictor of unfavorable outcome after stroke.

Pancreatic cancer with leptomeningeal carcinomatosis: case report and literature review

Leptomeningeal carcinomatosis (LMC) associated with pancreatic cancer is an extremely rare complication. Symptoms vary depending on the site of invasion and include intracranial pressure, and cranial and spinal dysfunction making early diagnosis difficult. We describe a rare case of leptomeningeal metastasis from pancreatic cancer. A 59-year-old man was diagnosed with unresectable pancreatic cancer and subsequently received systemic chemotherapy. Initial chemotherapy was effective. After 12 months the patient's serum carbohydrate antigen (CA)19-9 level had become elevated, and he presented with neck and back pain, and shoulder stiffness. Tumor enlargement was not detected by computed tomography (CT) and positron emission tomography-CT. Contrast CT of the brain revealed evidence of leptomeningeal enhancement. Cerebrospinal fluid cytology showed atypical, but not malignant cells; the CA19-9 level was further elevated. The patient was finally diagnosed with LMC and, being in poor general condition, received palliative care. During the treatment of pancreatic cancer, the potential existence of LMC should be contemplated when a serum tumor marker becomes rapidly elevated despite the control of primary or metastatic sites.

BH3 profiling discriminates the anti‑apoptotic status of 5‑fluorouracil‑resistant colon cancer cells

5-Fluorouracil (5-FU) is a cytotoxic anticancer drug commonly used for patients with advanced colon cancer. This drug effectively reduces the size of tumors to a certain degree; however, cancer cells can gradually acquire resistance, resulting in disease progression. To identify the mechanism of 5-FU resistance, we established three 5-FU-resistant colon cancer cell lines and analyzed both apoptosis-related protein expression levels and BH3 profiling. These 5-FU-resistant colon cancer cell lines acquired apoptotic resistance to 5-FU. Although apoptosis-related protein expression levels were altered in each 5-FU-resistant colon cancer cell line variably, BH3 profiling indicated BCLXL dependence in 5-FU-resistant HT-29 cells only. Functional BCLXL inhibition in 5-FU-resistant HT-29 cells not only sensitized the cells to apoptosis but also overcame 5-FU resistance. The apoptotic BIM protein was preferentially sequestered, thereby resulting in acquired dependence on BCLXL for survival. Additionally, in vivo models showed that BCLXL inhibition controlled tumor progression. These results indicate that BH3 profiling facilitates the identification of the functional role of anti-apoptotic proteins during drug resistance and has clinical implications for colon cancer in targeting specific proteins such as BCLXL.

P599Native T1 mapping is useful for detection of myocardial fibrosis in cases with ischemic and non-ischemic myocardial diseases

Background

Evaluation of myocardial fibrosis (MF) as late gadolinium enhancement (LGE) on MRI is useful for differential diagnosis of various myocardial diseases and prediction of future adverse cardiac events in some specific myocardial diseases. Gadolinium contrast is contraindicated for cases with severe renal dysfunction, therefore non contrast MRI is necessary for detection of MF in cases with both myocardial disease and severe renal dysfunction.

Purpose

We aimed to evaluate diagnostic accuracy of native T1 mapping for detection of MF compared with LGE in cases with various myocardial diseases, including ischemic and non-ischemic myocardial diseases.

Methods

We selected consecutive 40 patients who were suspected of having various myocardial diseases and underwent cardiac MRI, using 1.5T MRI (Ingenia, Philips) in 10 cases (25%) or 3T MRI (Ingenia, Philips) in 30 cases (75%), including native T1 mapping (without contrast) and LGE using contrast media from Jan 2018 to Feb 2019 in our institution. We evaluated diagnostic accuracy for detection of MF in left ventricular myocardium (LVM) of native T1 mapping image compared with LGE as the gold standard, in a patient-based and segment-based analysis. In T1 mapping images, segmental high T1 lesions were defined as MF. In a segment-based analysis, MF was evaluated using 17 LVM segments model in American Heart Association.

Results

MF was detected in 139 LVM segments in 25 (63%) cases. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of native T1 mapping for detection of MF were 90%, 89%, 95%, 80% and 90% in a patient-based analysis, and 63%, 96%, 84%, 89% and 88% in a segment-based analysis (left figure). Native T1-values of LVM with MF were significantly higher than LVM without LGE (1351±79 vs 1093±124 in 1.5T and 1562±131 vs 1291±43 in 3T) (p<0.05 and p<0.01). Interobserver agreement of native T1 mapping and LGE were not significantly different (0.88 and 0.89, P=0.70). Overall diagnostic accuracy of native T1 mapping for detection of MF in a patient-based analysis, was not significantly different in between the cases with ischemic (n=18) and non-ischemic (n=22) myocardial disease (90% and 83.3%, P=0.10).

Conclusion

Native T1 mapping (without contrast) is useful for detection of MF in various myocardial diseases and high diagnostic accuracy is expected especially in a patient-based analysis.

P6182Combination of a new iterative reconstruction technique with low tube voltage and high tube current has important role of detection of late enhancement on 320 slice CT

Background

New iterative reconstruction tecniques, including Adaptive Iterative Dose Reduction 3D (AIDR 3D) and Forward Projected Model-based Iterative Reconstruction SoluTion (FIRST), have been recently available on new generation 320 slice CT, and they can provide high-quality CT images.

Purpose

The aim of this study was to evaluate the diagnostic performance of detection of abnormal late enhancement (LE) in left ventricular (LV) myocardium (LVM) using 320-slice CT with new iterative reconstruction techiniques, AIDR 3D (Figure A) and FIRST (Figure B).

Methods

A total of 100 patients who were suspected of having various myocardial diseases and underwent late phase acquisition both on cardiac CT and CMR within 3 months were analyzed. The first 50 consecutive patients (Group 1) underwent 320-slice CT with AIDR 3D, 120 Kv tube voltage, 519±71 mA tube current. The next 50 consecutive patients (Group 2) underwent 320-slice CT with FIRST, 80 or 100Kv tube voltage, 803±20 mA tube current. We compared diagnostic accuracy of CT for detection of LE in LVM against that of CMR (the gold standard) in between the 2 groups.

Results

On patient-by-patient analysis, sensitivity, specificity, positive (PPV) and negative predictive values (NPV), and overall accuracy for detection of LE on CT vs CMR were 87, 95, 96, 82, and 90% in Group 1, and 97, 83, 91, 88, and 90% in Group 2. There were no significant difference of diagnostic accuracy on patient-by-patient analysis in between the 2 groups (Figure C). However, on a segment-by-segment analysis (using 17 American Heart Association LV segment model), these values for detection of LE on CT vs CMR were 60, 95, 73, 91, and 88% in Group 1, and 85, 95, 86, 95, and 93% in Group 2. Sensitivity, PPV, NPV and overall accuracy were significantly higher in Group 2 than in Group 1 (all P<0.01) (Figure D).

Conclusions

Diagnostic accuracy of detection of LE in LVM on CT combining low tube voltage and high tube current acquisition on a new generation 320-slice CT with FIRST was superior to 320-slice CT with AIDR 3D.

Acknowledgement/Funding

TSUCHIYA MEMORIAL MEDICAL FOUNDATION

P6578Development of the novel program to diagnose atrial fibrillation using automated blood pressure monitor

Background

Atrial fibrillation (AF) is often asymptomatic and contributes to an increased risk of strokes. The development of proper screening device of AF is unmet medical needs worldwide. Recently, we had reported that multiple measurements using Omron automated blood pressure (BP) monitor with irregular heartbeat detection showed high sensitivity and specificity for AF detection in general cardiac patients, however, this method had limitations in discriminating between AF and other arrhythmias.

Purpose

The aim of this study is to develop a novel program that can accurately diagnose AF by discriminating it from other arrhythmias using the pressure pulse waveform data outputted from Omron automated BP monitor.

Methods

In our previous clinical research, BP measurements were performed 3 times each for 303 general cardiac patients (mean age: 72.2 years, 69.8% male) with recording the real-time single lead ECG, and a total of 909 pressure pulse waveforms were obtained. Among them, 840 pressure pulse waveforms from 280 patients (include 40 AF patients) used for further analysis. We developed a program to analyze and visualize uniquely the characteristics of AF waveform through the autocorrelation-based waveform processing system produced by Melody International Ltd, Kagawa, Japan. All visualized results were judged and classified into Sinus, Non-AF and AF by two individuals blinded to the results. For each patient who obtained 3 results, a two by two contingency table was created and sensitivity, specificity, and accuracy for diagnosing AF were calculated.

Results

Among 840 pressure pulse waveforms, only 21 (2 Sinus and 19 Non-AF) out of 720 Sinus and Non-AF waveforms were judged as AF, and 7 out of 120 AF waveforms were judged as Non-AF. None of AF waveforms was absolutely misjudged as Sinus. In analysis for each patient, when one or more AF judgements were found in 3 waveforms, the diagnosis of AF has sensitivity and specificity of 100% and 95.8%, respectively. When two or more AF judgements were found in 3 waveforms, the diagnosis of AF has sensitivity and specificity of 100% and 97.9%, respectively. In this rule, the diagnostic accuracy of AF reached up to 98.8%, and no sinus patients were misjudged as AF.

Conclusion

The novel program, which applied autocorrelation methods uniquely to analysis of the pressure pulse waveforms recorded by automated BP monitor, showed high sensitivity and high specificity for AF diagnosis in general cardiac patients. This program is expected to be useful for early diagnosis for asymptomatic AF patients.

Acknowledgement/Funding

The present research is supported by a grant through the SCOPE from the Ministry of Internal Affairs and Communications, Japan.

Honeycomb blocks composed of carbonate apatite, β-tricalcium phosphate, and hydroxyapatite for bone regeneration: effects of composition on biological responses

Synthetic scaffolds exhibiting bone repair ability equal to that of autogenous bone are required in the fields of orthopedics and dentistry. A suitable synthetic bone graft substitute should induce osteogenic differentiation of mesenchymal stem cells, osteogenesis, and angiogenesis. In this study, three types of honeycomb blocks (HCBs), composed of hydroxyapatite (HAp), β-tricalcium phosphate (TCP), and carbonate apatite (CO3Ap), were fabricated, and the effects of HCB composition on bone formation and maturation were investigated. The HC structure was selected to promote cell penetration and tissue ingrowth. HAp and β-TCP HCBs were fabricated by extrusion molding followed by sintering. The CO3Ap HCBs were fabricated by extrusion molding followed by sintering and dissolution-precipitation reactions. These HCBs had similar macroporous structures: all harbored uniformly distributed macropores (∼160 ​μm) that were regularly arrayed and penetrated the blocks unidirectionally. Moreover, the volumes of macropores were nearly equal (∼0.15 ​cm3/g). The compressive strengths of CO3Ap, HAp, and β-TCP HCBs were 22.8 ​± ​3.5, 34.2 ​± ​3.3, and 24.4 ​± ​2.4 ​MPa, respectively. Owing to the honeycomb-type macroporous structure, the compressive strengths of these HCBs were higher than those of commercial scaffolds with intricate three-dimensional or unidirectional macroporous structure. Notably, bone maturation was markedly faster in CO3Ap HCB grafting than in β-TCP and HAp HCB grafting, and the mature bone area percentages for CO3Ap HCBs at postsurgery weeks 4 and 12 were 14.3- and 4.3-fold higher and 7.5- and 1.4-fold higher than those for HAp and β-TCP HCBs, respectively. The differences in bone maturation and formation were probably caused by the disparity in concentrations of calcium ions surrounding the HCBs, which were dictated by the inherent material resorption behavior and mechanism; generally, CO3Ap is resorbed only by osteoclastic resorption, HAp is not resorbed, and β-TCP is rapidly dissolved even in the absence of osteoclasts. Besides the composition, the microporous structure of HC struts, inevitably generated during the formation of HCBs of various compositions, may contribute to the differences in bone maturation and formation.