Insulin-like Growth Factor II mRNA-binding Protein 3 is a Highly Sensitive Marker for Intravascular Large B-cell Lymphoma: Immunohistochemical Analysis of 152 Pathology Specimens From 88 Patients

Intravascular large B-cell lymphoma (IVLBCL) is a rare type of aggressive extranodal large B-cell lymphoma characterized by the selective growth of lymphoma cells within the lumina of blood vessels, particularly capillaries. IVLBCL lacks mass formation, and its diagnosis can be challenging. We analyzed the utility of insulin-like growth factor II mRNA-binding protein 3 (IMP3) immunohistochemistry for IVLBCL diagnosis in various organs. Double staining with paired box 5 (PAX5) was performed for validation. Overall, 152 pathological specimens (111 positive and 41 negative for IVLBCL) obtained from 88 patients with a diagnosis of IVLBCL were stained for IMP3 and IMP3/PAX5. As negative controls, 40 pathology specimens from 38 patients with no history of IVLBCL or other B-cell lymphomas were stained for IMP3, which comprised 31 benign pathological specimens from 29 patients in whom malignancy was suspected, 7 cases of appendicitis with intravascular and/or intralymphatic lymphoid proliferations, and 2 cases of intravascular natural killer/T-cell lymphoma. All mononuclear cells with cytoplasmic staining were considered positive for IMP3 expression, but expression restricted to germinal center B cells was excluded from evaluation. All 111 IVLBCL pathological specimens were positive for IMP3 and IMP3/PAX5. In addition, 11 of the 41 specimens originally diagnosed as IVLBCL-negative showed IMP3/PAX5 double-positive cells, raising the suspicion of IVLBCL. However, of the 40 negative control samples, IMP3-positive non-germinal center B cells were detected in only 2 samples ( P = 0.0131) and no intravascular IMP3-positive B cells suspicious for IVLBCL were identified. Altogether, IMP3 immunohistochemistry is a highly sensitive marker of IVLBCL and can be a helpful adjunct for IVLBCL diagnosis.

Evaluating Fourier-transform infrared spectroscopy with IR Biotyper as a faster and simpler method for investigating the sources of an outbreak of legionellosis

Fourier-transform infrared (FTIR) spectroscopy using the IR Biotyper and core genome single nucleotide polymorphism (cgSNP) analysis were performed on 12 Legionella isolates associated with an outbreak at a spa house in Kanagawa Prefecture, Japan, and 3 non-outbreak isolates. The discriminative power of FTIR spectroscopy for 48-h incubation conditions of L. pneumophila in this outbreak was lower than cgSNP-based typing but higher than serogroup typing. FTIR spectroscopy could screen outbreak isolates from a group of genetically related isolates and may be useful as an initial typing method in Legionella outbreak investigations.

A Deep Learning-Based Assay for Programmed Death Ligand 1 Immunohistochemistry Scoring in Non-Small Cell Lung Carcinoma: Does it Help Pathologists Score?

Several studies have developed various artificial intelligence (AI) models for immunohistochemical analysis of programmed death ligand 1 (PD-L1) in patients with non-small cell lung carcinoma; however, none have focused on specific ways by which AI-assisted systems could help pathologists determine the tumor proportion score (TPS). In this study, we developed an AI model to calculate the TPS of the PD-L1 22C3 assay and evaluated whether and how this AI-assisted system could help pathologists determine the TPS and analyze how AI-assisted systems could affect pathologists' assessment accuracy. We assessed the 4 methods of the AI-assisted system: (1 and 2) pathologists first assessed and then referred to automated AI scoring results (1, positive tumor cell percentage; 2, positive tumor cell percentage and visualized overlay image) for final confirmation, and (3 and 4) pathologists referred to the automated AI scoring results (3, positive tumor cell percentage; 4, positive tumor cell percentage and visualized overlay image) while determining TPS. Mixed-model analysis was used to calculate the odds ratios (ORs) with 95% CI for AI-assisted TPS methods 1 to 4 compared with pathologists' scoring. For all 584 samples of the tissue microarray, the OR for AI-assisted TPS methods 1 to 4 was 0.94 to 1.07 and not statistically significant. Of them, we found 332 discordant cases, on which the pathologists' judgments were inconsistent; the ORs for AI-assisted TPS methods 1, 2, 3, and 4 were 1.28 (1.06-1.54; P = .012), 1.29 (1.06-1.55; P = .010), 1.28 (1.06-1.54; P = .012), and 1.29 (1.06-1.55; P = .010), respectively, which were statistically significant. For discordant cases, the OR for each AI-assisted TPS method compared with the others was 0.99 to 1.01 and not statistically significant. This study emphasized the usefulness of the AI-assisted system for cases in which pathologists had difficulty determining the PD-L1 TPS.

Clinicopathological features of cytokeratin 5-positive pulmonary adenocarcinoma

Cytokeratin 5 (CK5) is a marker for pulmonary squamous cell carcinoma; however, CK5 is sometimes present in pulmonary adenocarcinoma (ADC), and there is insufficient information regarding the clinicopathological features of CK5-positive ADC. We aimed to explore the clinicopathological characteristics of CK5-positive ADC using immunohistochemistry. We prepared the following two cohorts: a resected cohort containing 220 resected tumours for primarily studying the detailed morphological characteristics, and a tissue microarray (TMA) cohort containing 337 samples for investigating the associations of CK5 expression with other protein expressions, genetic and prognostic findings. CK5-positive ADC was defined to have ≥ 10% tumour cells and presence of CK5-positive tumour cells in the resected and TMA cohorts, respectively. CK5-positive ADCs were identified in 91 (16.3%) patients in the combined cohort. CK5-positive ADCs had male predominance (P = 0.012), smoking history (P = 0.001), higher stage (P < 0.001), histological high-grade components (P < 0.001), vascular invasion (P < 0.001), mucinous differentiation (P < 0.001), spread through airspaces (P < 0.001), EGFR wild-type (P < 0.001), KRAS mutations (P < 0.001), ALK rearrangement (P < 0.001) and ROS1 rearrangement (P = 0.002). In the resected cohort, more than half the CK5-positive ADCs (19 cases, 65.5%) showed mucinous differentiation; the remaining cases harboured high-grade components. In the TMA cohort, CK5-positive ADCs correlated with TTF-1 negativity (P = 0.002) and MUC5B, MUC5AC and HNF4alpha positivity (P < 0.001, 0.048, < 0.001). Further, CK5-positive ADCs had significantly lower disease-free and overall survival rates than CK5-negative ADCs (P < 0.001 for each). Additionally, multivariate analysis revealed that CK5 expression was an independent poor prognostic factor. CK5-positive ADCs showed aggressive clinical behaviour, with high-grade morphology and mucinous differentiation.

The dependence of acetylcholine on dynamic changes in the membrane potential and an action potential during spike timing-dependent plasticity induction in the hippocampus

The hippocampus is an important area for memory encoding and retrieval and is the location of spike timing-dependent plasticity (STDP), a basic phenomenon of learning and memory. STDP is facilitated if acetylcholine (ACh) is released from cholinergic neurons during attentional processes. However, it is unclear how ACh influences postsynaptic changes during STDP induction and determines the STDP magnitude. To address these issues, we obtained patch clamp recordings from CA1 pyramidal neurons to evaluate the postsynaptic changes during stimuli injection in Schaffer collaterals by quantifying baseline amplitudes (i.e., the lowest values elicited by paired pulses comprising STDP stimuli) and action potentials. The results showed that baseline amplitudes were elevated if eserine was applied in the presence of picrotoxin. In addition, muscarinic ACh receptors (mAChRs) contributed more to the baseline amplitude elevation than nicotinic AChRs (nAChRs). Moreover, the magnitude of the STDP depended on the magnitude of the baseline amplitude. However, in the absence of picrotoxin, baseline amplitudes were balanced, regardless of the ACh concentration, resulting in a similar magnitude of the STDP, except under the nAChR alone-activated condition, which showed a larger STDP and lower baseline amplitude induction. This was due to broadened widths of action potentials. These results suggest that activation of mAChRs and nAChRs, which are effective for baseline amplitudes and action potentials, respectively, plays an important role in postsynaptic changes during memory consolidation.

Visualizing Molecular-Scale Adsorption Structures of Anti-freezing Surfactants on Sapphire (0001) Surfaces at Different Concentrations by 3D Scanning Force Microscopy

Anti-freezing surfactants form an adsorption layer at the solid-water interface to inhibit the nucleation and growth of ice. However, this mechanism has not been elucidated at the molecular scale because of the difficulties in visualizing such adsorption structures. In this study, we overcome this limitation by directly visualizing the three-dimensional (3D) adsorption structures of anti-freezing surfactants, hexadecyltrimethylammonium bromide (C₁₆TABs), on sapphire (0001) surfaces through 3D scanning force microscopy. We present molecularly resolved two-dimensional/3D images of the adsorption structures in solutions of 1, 10, and 100 ppm. At 1 ppm, the molecules form a monolayer with a flat-lying configuration. At 10 ppm, the molecular orientation is closer to the upright configuration, with a relatively large tilt angle. At 100 ppm, the molecules form a bilayer with almost upright configurations, providing excellent screening of the sapphire surface from water. Owing to the steric and electrostatic repulsion between adjacent molecular head groups, the surface of the bilayer exhibits relatively large fluctuations, inhibiting the formation of stable ice-like structures. The understanding of molecular-level mechanisms provides important guidelines for improving the design of anti-freezing surfactants for practical applications such as car coolants.

P-138 Transcriptomic signatures in trophectoderm and inner cell mass of human blastocysts with expected pregnancy rates

Study question

Is it possible to identify the molecular factors that contribute to the implantation potential of blastocysts?

Summary answer

Genes correlated with expected pregnancy rate in trophectoderm (TE) and inner cell mass (ICM) respectively were identified, and aneuploidy alone couldn’t predict the pregnancy expectation.

What is known already

The selection of suitable embryos for transfer is critical for achieving successful pregnancy outcomes in assisted reproductive technology (ART). Although pre-implantation genetic testing for aneuploidy (PGT-A) as well as morphological and chronological evaluation of embryos, have been conducted in clinical practice, they do not fully guarantee successful pregnancy. Recently, transcriptional events in early human embryonic development have been analyzed using RNA-sequencing (RNA-seq) and researchers are attempting to apply this information to ART.

Study design, size, duration

To determine the correlation between blastocyst evaluation and pregnancy rate, we retrospectively analyzed 1,890 cases underwent frozen-thawed blastocyst transfer from March 2018 to December 2020. A total of 13 blastocysts that were cryopreserved for clinical use between February 2011 and September 2018, then scheduled for disposal and with consented for research, were subjected to RNA-seq without distinguishing between conventional in vitro fertilization (c-IVF) and intracytoplasmic sperm injection (ICSI).

Participants/materials, setting, methods

Blastocysts were donated by infertile couples undergoing c-IVF or ICSI cycles at the Yamashita Shonan Yume Clinic with informed consent under ethical approval. TE and ICM cells were collected from blastocysts by using a micromanipulator and then subjected to RNA-seq. Gene expression analysis and digital karyotyping using RNA-seq were performed simultaneously for TE and ICM cells, respectively. One-way analysis of variance, chi-square test and Tukey's multiple comparison test were used for this study.

Main results and the role of chance

Blastocysts were classified into three groups to correlate with pregnancy rates based on the diameter of the blastocyst and the time to reach this size: those taking less than 130 h to reach a diameter of &gt; 170 μm (Group 1, n = 676), those taking more than 140 h to reach a diameter of &lt; 180 μm (Group 2, n = 158), and the rest (Group 3, n = 1,056). The pregnancy rates of Groups 1, 2 and 3 were 59.0%, 16.5%, and 34.2%, respectively (p &lt; 0.01). Assessing the differences in overall transcripts correlated between Group 1 (n = 5), Group 2 (n = 4), and Group 3 (n = 4), 26 and 67 differentially expressed genes (DEGs) were identified in ICM and TE cells, respectively. Importantly, downregulated genes in TE of blastocysts with lower expectation of pregnancy included tight junction-related genes, such as CXADR, CLDN10, and ATP1B1, which were implicated in peri-implantation development. Digital karyotyping revealed karyotypic abnormalities and mosaicism in all groups with no common abnormalities observed, suggesting that aneuploidy alone cannot predict the pregnancy expectation.

Limitations, reasons for caution

Although 93 genes potentially related to implantation have been identified, it is still unclear how these genes are involved in implantation. In vitro implantation models using human embryos and artificial embryos currently under development are expected to contribute to the elucidation of the functions of these genes.

Wider implications of the findings

Our results provide reliable candidates for genes that could allow for non-invasive selection of high-quality blastocysts for ART and add to the knowledge base of transcriptional events in human peri-implantation development.

Trial registration number

not applicable

P-198 An analysis of the size of micro pronucleus in 2.1 pronuclear zygotes by using time-lapse images

Study question

Is it possible to determine the difference between 2.1 pronuclear (2.1PN) zygotes and tripronuclear (3PN) zygotes from time-lapse images?

Summary answer

A pronucleus of less than 15 μm in diameter can be considered the micro pronucleus (micro PN), and it is possible to classify 2.1PN zygotes.

What is known already

2.1PN zygotes are defined as zygotes with two pronuclei and one smaller pronucleus. Capalbo et al.  (2017) reported that most of the 2.1PN-derived blastocysts were diploid by preimplantation genetic testing for aneuploidy (PGT-A), including single-nucleotide polymorphisms (SNPs) analysis. Thus, the treatment with 2.1 PN zygotes should be performed with chromosome testing. In Japan, where PGT-A is not available in principle, 2.1PN zygotes are rarely used in the embryo transfer. On the other hand, the size of the micro pronucleus in 2.1PN zygotes has not been clearly defined, and it is difficult to determine differences between 2.1PN and 3PN zygotes.

Study design, size, duration

The study was performed retrospectively on 2463 cycles of in vitro fertilization (IVF) conducted at our clinic between August 2020 and December 2021. A total of 3073 embryos underwent conventional-IVF (c-IVF) or intracytoplasmic sperm injection (ICSI) and were cultured in the time-lapse incubator, of which 221 zygotes with three pronuclei were used in the study.

Participants/materials, setting, methods

The diameter of the three PNs at one hour before syngamy from time-lapse images; 2.1 PN and 3PN zygotes were classified in the report by Capalbo et al. (2017). The age of the patients and the method of insemination between the groups were compared, and the diameter of the micro PN was analysed. Moreover, logistic regression analysis was performed to investigate the predictor of 2.1PN zygotes from the morphological characteristics of oocytes at ICSI.

Main results and the role of chance

The mean age of each patient was 42.9 years for 2.1PN zygotes and 39.8 years for 3PN zygotes, significantly higher for 2.1PN zygotes (P =0.003). On the other hand, when comparing the stage of oocyte maturation at the time of oocyte retrieval, there was no significant difference (P =0.749). According to the insemination method, the incidence of 2.1PN zygotes was significantly higher in ICSI (including rescue-ICSI) compared to c-IVF: 32.9% [95%CI: 22.5-44.6%] vs 2.4% [95%CI: 0.1-12.9%] (P &lt;0.001). In terms of ICSI-derived zygotes, the mean age was also significantly higher for 2.1PN zygotes compared to 3PN zygotes: 43.3 years vs. 40.9 years (P =0.03). The diameter of micro PNs calculated using the receiver operating characteristics (ROC) curve from the measurements of the diameter was less than 15 μm (AUC [95%CI]: AUC=0.988 [0.975-1.00]). Logistic regression analysis using age, position of the oocyte spindle at ICSI, cytoplasmic viscosity, and condition of the cell membrane as explanatory variables revealed a significant difference only in age (P =0.0154, odds ratio [95%CI]: 1.18 [1.03-1.35]) and no statistically significant oocyte morphological characteristics.

Limitations, reasons for caution

In this study, we have not investigated whether 2.1 PN zygotes become blastocysts. It will be necessary to further examine the criteria for 2.1PN along with chromosome testing to investigate the use of 2.1PN-derived blastocysts.

Wider implications of the findings

A pronucleus of less than 15 μm in diameter can be considered a micro PN. Compared to 3PN zygotes, 2.1PN zygotes were more frequently observed in older patients and in ICSI-derived zygotes. However, it is difficult to predict the incidence of 2.1PN zygotes from the oocytes’ morphological characteristics at ICSI.

Trial registration number

not applicable

Peritumoral radiomics features on preoperative thin-slice CT images can predict the spread through air spaces of lung adenocarcinoma

The spread through air spaces (STAS) is recognized as a negative prognostic factor in patients with early-stage lung adenocarcinoma. The present study aimed to develop a machine learning model for the prediction of STAS using peritumoral radiomics features extracted from preoperative CT imaging. A total of 339 patients who underwent lobectomy or limited resection for lung adenocarcinoma were included. The patients were randomly divided (3:2) into training and test cohorts. Two prediction models were created using the training cohort: a conventional model based on the tumor consolidation/tumor (C/T) ratio and a machine learning model based on peritumoral radiomics features. The areas under the curve for the two models in the testing cohort were 0.70 and 0.76, respectively (P = 0.045). The cumulative incidence of recurrence (CIR) was significantly higher in the STAS high-risk group when using the radiomics model than that in the low-risk group (44% vs. 4% at 5 years; P = 0.002) in patients who underwent limited resection in the testing cohort. In contrast, the 5-year CIR was not significantly different among patients who underwent lobectomy (17% vs. 11%; P = 0.469). In conclusion, the machine learning model for STAS prediction based on peritumoral radiomics features performed better than the C/T ratio model.

Mill Processability, Rheology and Structure Differences of Polyacrylate Elastomers

Two commercial polyacrylate elastomers, one having epoxide (EP) crosslinking sites and the other ethylidene norbornene (ENB) were selected. It was demonstrated that the former was more difficult to mill-process than the latter. The viscoelastic properties measured at very small strain in shear oscillation indicated that the ENB polymer was more branched than the EP polymer. The gel determination by filteration confirmed this. The tensile stress-strain measurements were conducted at four different deformation rates. These data were treated according to the strain-time correspondence principle to see if this principle applies to the data of these samples. The data of EP polymer did not form a master curve, thus, the above principle is not applicable; at the larger deformation the strain-hardening tendencies were observed. This indicates that the EP polymer has a rather extensive long branching, a type of which usually results from a chain transfer reaction.

The data of the ENB polymer, on the other hand, form a master-curve; that is, the strain-time correspondence principle is applicable, in spite of the presence of the large amount of gel. This means that the gel in the ENB polymer is microgel. The micro-gel in this case is polymer-latex particle, crosslinked during emulsion polymerization with a difunctional comonomer.

Thus, in this work polymer rheology was effectively used to find a major difference in the polymer chain structure. In this way it was shown that the results of polymerization may be related to mill processability.

High programmed death ligand 1 expression in carcinomatous components predicts a poor prognosis in pulmonary pleomorphic carcinoma

PURPOSE

This study reviewed the clinicopathological characteristics and programmed death ligand 1 (PD-L1) expression of 46 patients with pulmonary pleomorphic carcinoma to better understand its clinical behavior and factors affecting the survival.

METHODS

Data of patients with pulmonary pleomorphic carcinomas resected in our institution were retrospectively reviewed. The tumors were classified as carcinomatous or sarcomatous according to the tissue components. Pathological characteristics were evaluated on hematoxylin and eosin-stained sections. The percentages of tumor cells with membrane staining for PD-L1 in carcinomatous and sarcomatous components were determined.

RESULTS

We reviewed data of 46 patients (41 males, 5 females; median age 70.5 years old, range 36-83 years old). Most patients with pulmonary pleomorphic carcinoma expressed PD-L1 (80.4%), and the proportion of PD-L1 expression in tumor cells was significantly higher in sarcomatous components than in carcinomatous components. In univariable analyses, high p-stage (III), necrosis on pathological findings, and high PD-L1 expression in carcinomatous components (≥ 50%) were poor prognostic factors for the overall survival. In multivariable analyses, high PD-L1 expression in carcinomatous components was significantly associated with a poor prognosis after surgery.

CONCLUSIONS

High PD-L1 expression in carcinomatous components was significantly associated with a poor prognosis after surgery.

Clinical, radiological, and pathological features of idiopathic and secondary interstitial pneumonia cases with pleuroparenchymal fibroelastosis undergoing lung transplantation

AIMS

Idiopathic pleuroparenchymal fibroelastosis (PPFE) is a rare type of idiopathic interstitial pneumonia, and pathological PPFE is also observed in secondary interstitial pneumonia. This study aimed to evaluate the pathological findings associated with radiological PPFE-like lesions and the clinical and morphological features of patients with pathological PPFE.

METHODS AND RESULTS

We retrospectively reviewed the pathology of the explanted lungs from 59 lung transplant recipients with radiological PPFE-like lesions. Pathological PPFE lesions were identified in 14 patients with idiopathic cases and 12 patients with secondary cases. Pathological PPFE was associated with previous pneumothorax, a volume loss in the upper lobes and a flattened chest. Patients with idiopathic and secondary cases with pathological PPFE had similar clinical, radiological, and pathological findings, while fibroblastic foci were more common in patients with idiopathic cases, and patients with secondary cases more frequently showed alveolar septal thickening with elastosis or fibrosis. Post-transplantation survival did not differ between patients with idiopathic and secondary cases with pathological PPFE (log-rank; P=0.57) and was similar between patients with idiopathic cases with pathological PPFE and patients with idiopathic pulmonary fibrosis (IPF) (log-rank; P = 0.62).

CONCLUSIONS

Not all patients with interstitial pneumonia with radiological PPFE-like lesions have pathological PPFE. Characteristic clinical features can suggest the presence of pathological PPFE, and idiopathic and secondary cases with pathological PPFE are similar except for fibroblastic foci in idiopathic cases and alveolar septal thickening with elastosis or fibrosis in secondary cases. Patients with pathological PPFE have a similar prognosis to those with IPF after transplantation.

The importance of central airway dilatation in patients with bronchiolitis obliterans

Background

Bronchiolitis obliterans (BO) is a clinical syndrome characterised by progressive small airway obstruction, causing significant morbidity and mortality. Central airway dilatation is one of its radiological characteristics, but little is known about the clinical and pathological associations between airway dilatation and BO.

Methods

This retrospective study consecutively included patients who underwent lung transplantation due to BO at Kyoto University Hospital from 2009 to 2019. Demographic and histopathological findings of the resected lungs were compared between patients with and without airway dilatation measured by chest computed tomography (CT) at registration for lung transplantation.

Results

Of a total of 38 included patients (median age, 30 years), 34 (89%) had a history of hematopoietic stem-cell transplantation, and 22 (58%) had airway dilatation based on CT. Patients with airway dilatation had a higher frequency of Pseudomonas aeruginosa isolation with greater residual volume than those without airway dilatation. Quantitative CT analysis revealed an increase in lung volume to predictive total lung capacity and a percentage of low attenuation volume <−950 HU at inspiration in association with the extent of airway dilatation. Airway dilatation on CT was associated with an increased number of bronchioles with concentric narrowing of the lumen and thickening of the subepithelium of the walls on histology.

Conclusions

In patients with BO, airway dilatation may reflect increased residual volume or air trapping and pathological extent of obstructive bronchioles, accompanied by a risk of Pseudomonas aeruginosa isolation. More attention should be paid to the development of airway dilatation in the management of BO.

In patients with bronchiolitis obliterans (BO), airway dilatation may reflect air trapping and the pathological extent of obstructive bronchioles. More attention should be paid to airway dilatation in the management of BO.https://bit.ly/3w7cRV6

P–248 Statistical estimation for incidence of blastocyst trophectoderm vesicles (TVs) and efficacy of assisted hatching (AH)

Study question

The aim of this study is to analyse the association between blastocyst diameter and TVs development, and to examine the efficacy of AH.

Summary answer

Blastocysts with a diameter of more than 170 μm leads to high incidence of TVs and AH applied from the incidence should be effective.

What is known already

TVs are protrusion of trophectoderm cells often observed in expanding blastocyst stages. TVs can be observed in expanding blastocysts regardless of Intracytoplasmic sperm injection (ICSI) and Conventional-IVF (C-IVF), when the internal pressure of blastocysts increase. The rate of TVs incidence in blastocysts inseminated by ICSI is higher than that by C-IVF, due to penetration of the needle into the zona pellucida. Moreover, it has been reported that TVs may inhibit blastocyst hatching. However, the developmental timing of TVs is still unclear, and there is no study that has analysed the association between blastocyst diameter and the incidence of TVs.

Study design, size, duration

1) Diameters and TVs incidence of blastocysts by ICSI and C-IVF were measured, and the cut-off value and the area under the curve (AUC) of the receiver operating characteristic (ROC) curve were calculated to estimate the timing of TV incidence. 2) We analysed the clinical pregnancy rates of blastocysts with TVs treated by AH compared to those of blastocysts by C-IVF not subjected to AH.

Participants/materials, setting, methods

This study included 821 transferred frozen blastocysts ranging from March 2018 to November 2019. The embryos were cultured in a dry incubator after insemination by ICSI or C-IVF. Blastocyst freezing conditions were set at day5 to day7 with a diameter of more than 150 μm in inner diameter of zona pellucida, and this was measured before freezing. The ROC curve was performed using EZR statistical analysis software.

Main results and the role of chance

1) The incidence of TVs in blastocysts by ICSI and C-IVF was 27.5% (117/424) and 14.6% (58/397) respectively. The rate of the incidence of TVs in blastocysts inseminated by ICSI and C-IVF; 8.6% (12/140) and 0.95% (1/105) in 150–159 μm, 12.7% (14/110) and 8.2% (6/73) in 160–169 μm, 40.6% (28/69) and 10.5% (6/57) in 170–179 μm, 55.6% (30/54) and 25.5% (13/51) in 180–189 μm, 66.7% (20/30) and 35.7% (10/28) in 190–199 μm, and 68.4% (13/19) and 26.8% (22/82) in the diameter of more than 200 μm. The cut-off value of the ROC curve was respectively 170 μm (sensitivity 78.6% and specificity 73.0%) and 176 μm (sensitivity 84.5% and specificity 59.6%) in the diameter; the AUC was 0.8 [95%CI:0.752–0.848] and 0.74 [95%CI:0.687–0.793] respectively. 2) The clinical pregnancy rate of TVs blastocyst vs C-IVF blastocyst was 52.7% (88/167) vs 57.8% (37/64) respectively. There is no significant difference between the two clinical pregnancy rates (P = 0.556).

Limitations, reasons for caution

The findings of this study have to be seen in light of some limitations. Since this study aimed to analyse the incidence of TVs based on blastocyst size, we did not take into account the grade according to the Gardner classification and the number of trophectoderm cells.

Wider implications of the findings: Blastocysts inseminated by ICSI and C-IVF were highly likely to have TVs above 170 μm and 176 μm respectively. The clinical pregnancy rates of the blastocyst with TV treated by AH was similar to those of the C-IVF blastocyst.

Trial registration number

Not applicable

Validation Study of the International Association for the Study of Lung Cancer Histologic Grading System of Invasive Lung Adenocarcinoma

INTRODUCTION

A histologic grading system for invasive lung adenocarcinoma (ADC) has been proposed by the International Association for the Study of Lung Cancer (IASLC) Pathology Committee in June 2020. This study evaluated the prognostic value of the IASLC histologic grading system (the IASLC system) in a large Japanese cohort.

METHODS

We performed comprehensive histologic subtyping using the semiquantitative estimation of five major patterns and complex glandular patterns in patients with a completely resected lung ADC and determined the histologic grade using the IASLC system. Concordance index and receiver-operating characteristic curves were used to evaluate the clinical utility of the IASLC system for recurrence and death; the comparison was performed with the architectural-pattern system (the Arch system) and the grading system on the basis of the two most predominant patterns (the Sica's system).

RESULTS

Of 1002 patients with invasive ADC, 235 had recurrent disease and 166 died of lung cancer. The concordance index and area under the curve of the IASLC system were 0.777 and 0.807 for recurrence and 0.767 and 0.776 for death, respectively. These were similar to those of the Arch system (0.763 and 0.796 for recurrence, 0.743 and 0.755 for death) and the Sica's system (0.786 and 0.814 for recurrence, 0.762 and 0.773 for death).

CONCLUSIONS

We reported that the IASLC system for invasive lung ADC has prognostic significance by evaluating a large Japanese cohort. We believe that the IASLC grading system will provide physicians with better information for postsurgery treatment.

Prognostic significance of cribriform adenocarcinoma of the lung: validation analysis of 1,057 Japanese patients with resected lung adenocarcinoma and a review of the literature

Background

Cribriform-predominant adenocarcinoma of the lung (Cribri-ADC) is a recently described tumor growth pattern. However, its prognostic impact has not been clearly determined. We analyzed the data of a series of 1,057 Japanese patients with resected lung adenocarcinoma to identify the clinical significance of Cribri-ADC.

Methods

Cribriform pattern (Cribri-p) is defined as invasive back-to-back fused tumor glands with poorly formed glandular spaces or invasive tumor nests comprising tumors cells that produced glandular lumina. We investigated the correlations of Cribri-p and Cribri-ADC with clinicopathological factors as well as disease-free survival (DFS) and overall survival (OS).

Results

Cribri-p was present in 217 patients (20.5%) and Cribri-ADC was determined in 25 patients (2.4%). Cribri-p was associated with larger tumor size, pleural invasion, vascular invasion, lymphatic invasion, and spreading through air spaces (STAS) (all, P<0.0001). Cribri-ADC was associated with younger age (P=0.019), vascular invasion (P=0.0025), STAS (P<0.0001), and ALK rearrangement (P=0.012). The DFS curve of patients with Cribri-ADC was identical to that of patients with solid adenocarcinoma; however, the OS curve was located between that of patients with papillary and acinar adenocarcinoma. Of the 10 patients who had tumor recurrences, eight had EGFR mutations or ALK rearrangement, six of whom achieved relatively long survival (median, 64.6, range, 37.4–113 months) following treatment with tyrosine kinase inhibitors (TKIs). In multivariate analysis, Cribri-ADC was not an independent prognostic factor of either recurrence or death.

Conclusions

Cribri-ADC is associated with a higher risk of recurrence; however, most patients can be successfully treated with TKIs.

Ciliated muconodular papillary tumor with a growing cavity shadow that mimicked colorectal metastasis to the lung: a case report

Background

Ciliated muconodular papillary tumor (CMPT) is a rare papillary nodule tumor with benign and malignant characteristics that occurs in the peripheral lung.

Case presentation

A 70-year-old woman who underwent right hemicolectomy for colorectal cancer (CRC; pT3N0M0, p-stage II) 2 years prior, presented with a sub-centimeter growing cavity shadow on chest computed tomography (CT), which was suspected to be a CRC metastasis. Because positron emission tomography CT suggested there was no other site suspicious of recurrence, thoracoscopic resection with preoperative pleural dye marking was planned to remove the small lesion, which seemed to be hardly palpable on CT. Immediately after pleural dye marking adjacent to the lesion using cone beam CT in the hybrid operating room, thoracoscopic wedge resection was performed and the tumor was finally diagnosed as CMPT, characterized by the papillary growth of mucus-producing cells in the alveoli.

Conclusion

We resected the non-palpable small lung lesions following preoperative marking using cone-beam CT in the hybrid operating room. This case highlights a rare cavitary CT image of a CMPT mimicking a metastatic lung tumor from colorectal cancer.

Association Between Pretransplant Serum Carcinoembryonic Antigen Levels and Immunohistochemical Staining of Explanted Native Lungs in Patients Who Underwent Lung Transplantation

Some patients show high serum carcinoembryonic antigen (CEA) levels in the evaluation of candidate patients for lung transplantation, which might be a challenge because high serum CEA potentially implies an existence of malignancy. For further understanding of the true meaning of high serum CEA levels in lung transplantation, we retrospectively investigated the relationship between serum CEA and clinical data. We also performed immunohistochemical analysis of explanted native lungs and evaluated its relationship with serum CEA levels. Retrospective chart review was performed in consecutive patients who underwent lung transplantation with measurement of serum CEA before and after transplantation at our institution between August 2008 and June 2017. Histopathological analysis was also performed in the same cohort of patients. Survival outcomes and pathohistological findings were compared between the high serum CEA and the normal CEA group, adjusting for potential confounding factors. One hundred and fifteen patients were eligible for analysis. High serum CEA levels before lung transplantation in most cases were decreased after the transplantation (35/39, 90%, P < 0.001). Preoperative serum CEA levels were not associated with postoperative survival. The percentage of CEA-positive alveolar cells was significantly higher in the high serum CEA group (P < 0.0001). After adjusting for potential confounding factors, there was a significant difference between the high serum CEA group and normal serum CEA group (CEA-positive alveolar cells; P = 0.002). High serum CEA levels before lung transplantation might derive from native lungs in the recipients and that they were not associated with overall survival after lung transplantation.

Large nest micropapillary pattern of lung adenocarcinoma has poorer prognosis than typical floret pattern: analysis of 1,062 resected tumors

Background

A micropapillary pattern (MP-p) is related to poor prognosis in patients with lung adenocarcinoma (L-ADC). In 2015, the WHO defined the MP-p as "papillary tufts forming florets that lack fibrovascular cores and may appear detached from alveolar walls"; however, the sizes of tumor clusters in air space were not mentioned in this classification.

Methods

We evaluated the MP-p dividing the cluster sizes in the air space by reviewing 1,062 cases of resected L-ADCs. We classified MP-p into two types according to cluster size as follows: typical floret MP-p, tumors with small-to-medium-sized clusters (1-20 tumor cells); and large nest MP-p, tumors with large-sized clusters (>20 tumor cells, large nest). We then recorded the frequency of each type and investigated the association between the MP-p type and clinicopathological factors.

Results

Twenty-nine percent of L-ADCs (n=308) were MP-p-positive. Typical floret MP-p and large nest MP-p were observed in 244 tumors (22.9%) and 64 tumors (6.0%), respectively. Only 7 additional micropapillary ADCs were detected when we reclassified ADCs in addition to large nest MP-p. Tumors with large nest MP-p showed the highest frequency of node metastasis and worse prognosis compared to those with typical floret MP-p and absent (P<0.001). In multivariate analysis, patients with L-ADC with typical floret MP-p and large nest MP-p showed a higher recurrence rate [hazard ratio (HR): 1.762 (type 1 vs. absent), HR: 2.450 (type 2 vs. absent)].

Conclusions

Large nest MP-p should be included in the original MP-p and recorded separately.

Survival outcomes of resection for pulmonary malignancies including non-small cell lung cancer and pulmonary metastasis after esophagectomy for esophageal carcinoma

OBJECTIVES

This study investigated survival outcomes of resection for pulmonary malignancies after esophagectomy for esophageal carcinoma, comparing non-small cell lung cancer and pulmonary metastases.

METHODS

We retrospectively reviewed consecutive patients who underwent resection for pulmonary malignancies after esophagectomy for esophageal carcinoma between 2009 and 2018. The overall survival and relapse-free survival rate were assessed using Kaplan-Meier analysis.

RESULTS

Eleven patients had non-small cell lung cancer and eight patients had pulmonary metastases from esophageal carcinoma. The 5-year overall survival rate was 92.9% in all patients with a median follow-up period of 50.4 (range: 9.1-130.2) months. While the 5-year overall survival rate was 100.0% in patients with non-small cell lung cancer, it was 85.7% in patients with pulmonary metastases from esophageal carcinoma. The 5-year relapse-free survival rate was 85.7% in patients with non-small cell lung cancer.

CONCLUSIONS

Our data suggest that resection for pulmonary malignancies after esophagectomy for esophageal carcinoma is associated with favorable survival outcomes and should be considered in selected patients.

Paratracheal Middle Mediastinal Thymic Carcinomas

We describe case studies of two patients who underwent resection of paratracheal middle mediastinal thymic carcinomas. In both patients, complete resection of these masses via right thoracotomy was performed using three-dimensional computed tomography. Final pathologic diagnoses were thymic squamous cell carcinoma and thymic atypical carcinoid tumor. Challenges and debates in preoperative, intraoperative, and postoperative management are discussed in this article.

P40 expression in small cell lung cancer: The presence of p40-positive cells does not always indicate squamous differentiation

Background

Small cell lung cancer (SCLC) is normally diagnosed with hematoxylin and eosin stains, although some cases require immunohistochemistry (IHC). P40 is highly sensitive and specific for squamous cell carcinoma and is thus considered the best marker for this cancer. However, the status of p40 expression in SCLC is not well known. The aim of this study was to analyze p40 expression in resected SCLC using IHC.

Methods

Forty‐four surgically resected SCLC cases were enrolled. Clinical data were obtained from the patients’ medical records. Pathologists blinded to the patients’ clinical data reviewed the SCLC slides. IHC was performed on a representative slide of each case.

Results

Although p40 was not diffusely expressed in any of the SCLC cases, p40‐positive cells were observed in the tumors in 15 cases (34.1%). Ten of these exhibited p40 in < 1% of tumor cells. In the remaining five cases, 1–5% of tumor cells expressed p40, and in three of these, the cells expressing p40 also expressed TTF‐1 and neuroendocrine markers. There was no statistically significant relationship between p40 positivity and any other clinicopathological characteristics.

Conclusions

Some resected SCLCs express p40 focally. This result suggests that the presence of positive p40 cells does not exclude a diagnosis of SCLC. Thus, small biopsy or cytology specimens with p40‐positive cells must be diagnosed carefully.

Development of novel force-limiting grasping forceps with a simple mechanism

OBJECTIVES

In endoscopic surgery, fragile tissues may be damaged by the application of excessive force. Thus, we developed novel endoscopic forceps with a simple force-limiting mechanism.

METHODS

The novel forceps were constructed with a leaf spring, and the spring thickness determines grasping pressure. We established an evaluation system (maximum score is 11 points) for lung tissue damage leading to complications. We tested the conventional forceps (186.8 kPa) and 3 novel spring forceps with the following thicknesses: 1.3 mm (53.0 kPa), 2.2 mm (187.7 kPa) and 2.8 mm (369.2 kPa). After grasping, peripheral canine lung tissues were microscopically examined for acute- and late-phase damages.

RESULTS

In the acute phase (20 sites), the novel forceps caused capillary congestion and haemorrhage in the subpleural tissue, whereas the conventional forceps caused deep tissue and pleural damages. In the late phase (30 sites), both forceps caused fibroblast formation and interstitial thickening, which progressed to the deeper tissues as grasping pressure increased. In the acute phase, the median scores were 2.0 and 6.0 for the novel and conventional forceps, respectively (P = 0.003). In the late phase, the median scores were 2.0, 2.5 and 5.0 for 1.3-, 2.2- and 2.8-mm thick forceps, respectively, and 5.0 for the conventional forceps (P < 0.001). In both phases, the novel forceps with grasping pressure set below 187.7 kPa (2.2 mm) caused significantly less lung tissue damage than the conventional forceps.

CONCLUSIONS

The novel endoscopic forceps are able to regulate the tissue-grasping pressure and induce less damage in lung tissues than conventional forceps.

A multichannel gated neutron detector with reduced afterpulse for low-yield neutron measurements in intense hard X-ray backgrounds

A design of multichannel gated photomultiplier tube (PMT) is presented for the 960-channel neutron time-of-flight detector at the Institute of Laser Engineering of Osaka University. This is important for the fusion science and the nuclear photonics where intense hard X-rays are generated from the interaction of ultra-short laser pulse of petawatt power density with matter. The hard X-rays often overload PMTs and cause signal-induced background noises called afterpulses, making the detection of subsequent neutrons impossible. For this reason, the PMTs are coupled with an electrical time-gating (ETG) system to avoid overloading. The ETG system disables the PMT by modulating the dynode potential during the primary X-ray flash. An after-pulsing suppression technique is demonstrated by applying a reverse bias voltage between the photocathode and the first dynode. The presented multichannel scheme provides a gate response time of 80 ns, a signal cutoff ratio of 2.5 × 10², and requires reasonably low power consumption.

Prevalence of Salmonella enterica Subspecies enterica in Red-Eared Sliders Trachemys scripta elegans Retailed in Pet Shops in Japan

We investigated the prevalence of Salmonella in 227 small red-eared sliders (Trachemys scripta elegans) from 2006 to 2008. A total of 130 turtles (57.3%) tested positive for S. enterica subsp. enterica. Twenty-two serotypes including S. Montevideo, S. Newport, S. Pomona, S. Braenderup, S. Sandiego, and S. Litchfield were identified. Salmonella strains with closely related pulsed field gel electrophoresis (PFGE) patterns were isolated from several shops located in different areas from 2006 to 2008. Antimicrobial resistance was detected among strains of S. Montevideo, S. Newport, S. Braenderup, S. Sandiego, and S. Litchfield. The relatedness of antimicrobial resistance and PFGE profiles was not observed. The PFGE patterns of S. Poona strains isolated in 2006 and 2008 and the causative strains of turtle-associated salmonellosis in 2006 were identical. These results revealed a high prevalence of Salmonella enterica subsp. enterica in red-eared sliders retailed in Japan. In addition, genetically closely-related strains of turtle-associated Salmonella were repeatedly introduced into Japan over the study period and were distributed widely in Japan. These Salmonella strains present a risk of a widely disseminated outbreak of turtle-associated salmonellosis.

GATA6-positive lung adenocarcinomas are associated with invasive mucinous adenocarcinoma morphology, hepatocyte nuclear factor 4α expression, and KRAS mutations

AIMS

GATA6 is known to play a role in lung development. However, its role in the carcinogenesis of lung cancer is not well studied. The aim of this study was to analyse GATA6 expression in lung adenocarcinomas (LAs) by immunohistochemistry (IHC) in order to define its association with clinicopathological characteristics.

METHODS AND RESULTS

IHC analysis of GATA6 was performed with tissue microarray slides containing 348 LAs. The association between GATA6 expression and clinicopathological parameters was evaluated. GATA6 expression in epithelial tumours other than lung cancer was also evaluated. GATA6 expression was found in 47 LAs (13.5%). This occurred more frequently in younger patients (P = 0.005), and was associated with the absence of lymph node metastasis (P =0.024), well-differentiated to moderately differentiated tumours (P < 0.001), the absence of lymphatic invasion (P = 0.020), and the absence of vascular invasion (P = 0.011). GATA6 expression was associated with mucin production (P < 0.001), the invasive mucinous adenocarcinoma subtype (P < 0.001), KRAS mutations (P = 0.026), expression of MUC2 (P < 0.001), CDX2 (P = 0.049), and MUC5AC (P < 0.001), and absence of expression of TTF-1 (P = 0.002). GATA6 expression was also associated with hepatocyte nuclear factor 4α (HNF4α) expression (P < 0.001). GATA6 expression tended to indicate better prognoses, whereas patients with HNF4α expression had significantly worse prognoses (P = 0.033). Of 270 tumours other than lung cancer, 110 expressed GATA6.

CONCLUSIONS

These findings suggest that GATA6 might interact with HNF4α and contribute to the development of mucinous-type LAs.

Full-layer mucosal histology in achalasia: Histological epithelial wave is characteristic in "pinstripe pattern"-positive achalasia

BACKGROUND

Previously, the mucosal histology in achalasia has only been investigated using superficial biopsy or surgically resected esophageal specimens in end-stage cases. We investigated the histology of the full-layer mucosa in early and advanced achalasia.

METHODS

Endoscopy was performed for the pinstripe pattern (PSP) (an early achalasia indicator) and dilation and thickening of the mucosa (advanced achalasia indicators). A mucosal entry site for peroral endoscopic myotomy was created using cap-fitted endoscopic mucosal resection to access the full-layer mucosa and the submucosa.

KEY RESULTS

Mucosal histology was compared between 32 patients with achalasia and 15 controls. Histological esophagitis with findings of inflammatory cell infiltration and dilated intercellular spaces was observed more in patients with achalasia than in controls (87.5% vs 13.3%, P<.001; 84.4% vs 46.7%, P=.049). Muscularis mucosae (MM) atrophy and epithelial wave were only observed in achalasia (40.6% vs 0%, P=.005; 28.1% vs 0%, P=.043). Fibrosis was more common in achalasia, but without statistical significance (31.3% vs 20.0%, P=.503). In achalasia with endoscopic dilation and thickening of the mucosa, MM atrophy was observed histologically, and in cases involving endoscopic PSP, the histological epithelial wave was observed.

CONCLUSIONS & INFERENCES

Histological findings of esophagitis were observed endoscopically even in early achalasia. Pinstripe pattern corresponds to the epithelial wave observed histologically in achalasia, whereas endoscopic findings in advanced achalasia correspond to MM atrophy. Appropriate management is necessary during early achalasia to prevent progression to advanced achalasia with more severe histological changes.

Changes in esophageal motility after endoscopic submucosal dissection for superficial esophageal cancer: a high-resolution manometry study

The effect of endoscopic submucosal dissection (ESD) on esophageal motility remains unknown. Therefore, the aim of this study is to elucidate changes in esophageal motility after ESD along with the cause of dysphagia using high-resolution manometry (HRM). This is a before-and-after trial of the effect of ESD on the esophageal motility. Twenty patients who underwent ESD for superficial esophageal carcinoma were enrolled in this study. Patients filled out a questionnaire about dysphagia and underwent HRM before and after ESD. Results before and after ESD were compared. Data were obtained from 19 patients. The number of patients who complained of dysphagia before and after ESD was 1/19 (5.3%) and 6/19 (31.6%), respectively (P = 0.131). Scores from the five-point Likert scale before and after ESD were 0.1 ± 0.5 and 1.0 ± 1.6, respectively (P = 0.043). The distal contractile integral (DCI) before and after ESD and the number of failed, weak, or fragmented contractions were not significantly different. However, in five patients with circumferential ESD, DCI was remarkably decreased and the frequency of fail, weak, or fragmented contractions increased. Univariate regression analysis showed a relatively strong inverse correlation of ΔDCI with the circumferential mucosal defect ratio {P < 0.01, standardized regression coefficient (r) = -0.65}, the number of stricture preventions (P < 0.01, r = -0.601), and the number of stricture resolutions (P < 0.01, r = -0.77). This HRM study showed that impairment of esophageal motility could be caused by ESD. The impairment of esophageal motility was conspicuous, especially in patients with circumferential ESD and subsequent procedures such as endoscopic triamcinolone injection and endoscopic balloon dilatation. Impaired esophageal motility after ESD might explain dysphagia.

Evaluating the effectiveness of RNA in-situ hybridization for detecting lung adenocarcinoma with anaplastic lymphoma kinase rearrangement

AIMS

An easy and rapid assay for detecting mRNA in formalin-fixed paraffin-embedded samples [RNA in-situ hybridization (ISH)] has been reported recently. The aim of this study was to investigate the diagnostic accuracy of RNA ISH in detecting lung adenocarcinoma (LA) with anaplastic lymphoma kinase (ALK) gene rearrangement.

METHODS AND RESULTS

We tested ALK RNA ISH on 11 resected LAs for which ALK fusion was confirmed by immunohistochemistry (IHC) and/or fluorescence in-situ hybridization (FISH). ALK mRNA expression was detected by RNA ISH in all 11 ALK-positive LAs, with a mean positive cell proportion of 68.4% (median, 75.3%; range, 3-98.8%), by counting 100 tumour cells at 10 different loci; RNA ISH did not detect ALK mRNA expression in the normal surrounding lung cells. Next, we explored the concordance between ALK RNA ISH and IHC/FISH tests by using tissue microarrays (TMAs) containing 294 LAs. In the TMA slides, we found five ALK-positive cases with IHC and/or FISH. The mean proportion of ALK RNA ISH-positive cells in these five cases was 75.6% (median, 82%; range, 40-94%), whereas the proportion of ALK RNA ISH-positive cells in the remaining 289 cases was 0.3% (median 0%; range, 0-15%). When the cutoff value was set at 15%, ALK RNA ISH-positive and ALK RNA ISH-negative cases were distinguishable with 100% sensitivity and specificity relative to the IHC/FISH tests.

CONCLUSIONS

Our findings show that RNA ISH is useful for detecting ALK rearrangement with high sensitivity and specificity relative to conventional IHC/FISH tests. Thus, RNA ISH, which is an easy and rapid assay, could be an alternative method to IHC and FISH.