Addressing the knowledge gap in the genomic landscape and tailored therapeutic approaches to adolescent and young adult cancers

BACKGROUND

Adolescents and young adults (AYAs) represent a small proportion of patients with cancer. The genomic profiles of AYA patients with cancer are not well-studied, and outcomes of genome-matched therapies remain largely unknown.

PATIENTS AND METHODS

We investigated differences between Japanese AYA and older adult (OA) patients in genomic alterations, therapeutic evidence levels, and genome-matched therapy usage by cancer type. We also assessed treatment outcomes.

RESULTS

AYA patients accounted for 8.3% of 876 cases. Microsatellite instability-high and/or tumor mutation burden was less common in AYA patients (1.4% versus 7.7% in OA; P = 0.05). However, BRCA1 alterations were more common in AYA patients with breast cancer (27.3% versus 1.7% in OA; P = 0.01), as were MYC alterations in AYA patients with colorectal cancer (23.5% versus 5.8% in OA; P = 0.02) and sarcoma (31.3% versus 3.4% in OA; P = 0.01). Genome-matched therapy use was similar between groups, with overall survival tending to improve in both. However, in AYA patients, the small number of patients prevented statistical significance. Comprehensive genomic profiling-guided genome-matched therapy yielded encouraging results, with progression-free survival of 9.0 months in AYA versus 3.7 months in OA patients (P = 0.59).

CONCLUSION

Our study suggests that tailored therapeutic approaches can benefit cancer patients regardless of age.

Pericardial effusion in oncological patients: current knowledge and principles of management

BACKGROUND

This article provides an up-to-date overview of pericardial effusion in oncological practice and a guidance on its management. Furthermore, it addresses the question of when malignancy should be suspected in case of newly diagnosed pericardial effusion.

MAIN BODY

Cancer-related pericardial effusion is commonly the result of localization of lung and breast cancer, melanoma, or lymphoma to the pericardium via direct invasion, lymphatic dissemination, or hematogenous spread. Several cancer therapies may also cause pericardial effusion, most often during or shortly after administration. Pericardial effusion following radiation therapy may instead develop after years. Other diseases, such as infections, and, rarely, primary tumors of the pericardium complete the spectrum of the possible etiologies of pericardial effusion in oncological patients. The diagnosis of cancer-related pericardial effusion is usually incidental, but cancer accounts for approximately one third of all cardiac tamponades. Drainage, which is mainly attained by pericardiocentesis, is needed when cancer or cancer treatment-related pericardial effusion leads to hemodynamic impairment. Placement of a pericardial catheter for 2-5 days is advised after pericardial fluid removal. In contrast, even a large pericardial effusion should be conservatively managed when the patient is stable, although the best frequency and timing of monitoring by echocardiography in this context are yet to be established. Pericardial effusion secondary to immune checkpoint inhibitors typically responds to corticosteroid therapy. Pericardiocentesis may also be considered to confirm the presence of neoplastic cells in the pericardial fluid, but the yield of cytological examination is low. In case of newly found pericardial effusion in individuals without active cancer and/or recent cancer treatment, a history of malignancy, unremitting or recurrent course, large effusion or presentation with cardiac tamponade, incomplete response to empirical therapy with nonsteroidal anti-inflammatory, and hemorrhagic fluid at pericardiocentesis suggest a neoplastic etiology.

Accuracy of Cardiac Output Measured by Fourth-Generation Flotrac and Lidcorapid, and Their Characteristics Regarding Systemic Vascular Resistance in Patients Undergoing Cardiac Surgery

OBJECTIVES

The clinical use of less-invasive devices that calculate the cardiac output from arterial pressure waveform is increasing. The authors aimed to evaluate the accuracy and characteristics of the systemic vascular resistance index (SVRI) of the cardiac index measured by 2 less-invasive devices, fourth-generation FloTrac (CI_FT) and LiDCOrapid (CI_LR), compared with the intermittent thermodilution technique, using a pulmonary artery catheter (CI_TD).

DESIGN

This was a prospective observational study.

SETTING

This study was conducted at a single university hospital.

PARTICIPANTS

Twenty-nine adult patients undergoing elective cardiac surgery.

INTERVENTIONS

Elective cardiac surgery was used as an intervention.

MEASUREMENTS AND MAIN RESULTS

Hemodynamic parameters, CI_FT, CI_LR, and CI_TD, were measured after the induction of general anesthesia, at the start of cardiopulmonary bypass, after completion of weaning from cardiopulmonary bypass, 30 minutes after weaning, and at sternal closure (135 measurements in total). The CI_FT and CI_LR had moderate correlations with CI_TD (r = 0.62 and 0.58, respectively). Compared with CI_TD, CI_FT, and CI_LR had a bias of -0.73 and -0.61 L/min/m², limit of agreement of -2.14-to-0.68 L/min/m² and -2.42-to-1.20 L/min/m², and percentage error of 39.9% and 51.2%, respectively. Subgroup analysis for evaluating SVRI characteristics showed that the percentage errors of CI_FT and CI_LR were 33.9% and 54.5% in low SVRI (<1,200 dyne×s/cm⁵/m), 37.6% and 47.9% in moderate SVRI (1,200-1,800 dyne×s/cm⁵/m), 49.3% and 50.6% in high SVRI (>1,800 dyne·s/cm⁵/m²), respectively.

CONCLUSIONS

The accuracy of CI_FT or CI_LR was not clinically acceptable for cardiac surgery. Fourth-generation FloTrac was unreliable in high SVRI. LiDCOrapid was inaccurate across a broad range of SVRI, and minimally affected by SVRI.

Medium Diradical Character, Small Hole and Electron Reorganization Energies and Ambipolar Transistors in Difluorenoheteroles

Four difluorenoheteroles having a central quinoidal core with the heteroring varying as furan, thiophene, its dioxide derivative and pyrrole have shown to be medium character diradicals. Solid-state structures, optical, photophysical, magnetic, and electrochemical properties have been discussed in terms of diradical character, variation of aromatic character and captodative effects (electron affinity). Organic field-effect transistors (OFETs) have been prepared, showing balanced hole and electron mobilities of the order of 10^-3  cm²  V^-1  s^-1 or ambipolar charge transport which is first inferred from their redox amphoterism. Quantum chemical calculations show that the electrical behavior is originated from the medium diradical character which produces similar reorganization energies for hole and electron transports. The vision of a diradical as simultaneously bearing pseudo-hole and pseudo-electron defects might justify the reduced values of reorganization energies for both regimes. Structure-function relationships between diradical and ambipolar electrical behavior are revealed.

Donor-to-donor variability of a human three-dimensional bronchial epithelial model: A case study of cigarette smoke exposure

Three-dimensional (3D) cultured primary cells are used to predict the toxicity of substances towards humans because these 3D cultures closely mimic the physiological architecture of tissues. Nonetheless, it is important to consider primary-cell-specific variability for endpoint selection and appropriate evaluation of toxicity because donor-dependent characteristics may be retained even in in vitro cell cultures. In this report, 3D differentiated bronchial epithelial cells from three donors were used to investigate donor-to-donor variability, with an aqueous extract of cigarette smoke (CS) used as the test substance. Ciliary function, cytokine secretion, and histopathology, which are affected by CS, were examined, and transcriptomic analysis was also performed. The results revealed that interleukin-8 secretion and oxidative stress-related gene expression were consistently altered for all donors; however, their amplitudes varied. Moreover, one of the donors showed unique responses to CS, suggesting that this donor was an outlier. This donor showed intrinsic differences in histology, cytokine secretion, and gene expression profile. Such donors may help evaluate potential toxicological concerns and aid our understanding of disease pathogenesis. Conversely, these donors may confound toxicological assessment and endpoint selection. Fit-for-purpose handling of inter-donor variability is warranted.

POS0670 EVALUATION OF UPADACITINIB IN RHEUMATOID ARTHRITIS PATIENTS WITH INADEQUATE RESPONSE TO FIRST-GENERATION JANUS KINASE INHIBITORS

Background

Janus kinase inhibitors (JAKi) are effective in the treatment of patients with difficult-to-treat rheumatoid arthritis (D2T RA), regardless of previous use of biological disease-modifying antirheumatic drugs (bDMARDs), and receive equal billing with biological therapies in the latest version of the EULAR recommendations for treatment of RA1. However, as with bDMARDs, cases of discontinuation due to intolerance or inadequate response have been observed in patients treated with the so-called first-generation JAKi, leading to the development of a new generation of JAKi that aims to maximize efficacy and improve safety by enhancing kinase selectivity. The results of randomized controlled trials and meta-analyses suggest that the efficacy and safety of Upadacitinib (UPA) treatment are favorable. Although there have been no head-to-head trials between JAKi, a matched-adjusted indirect comparative study has shown a difference in efficacy between JAKi2, suggesting that the new generation of JAKi may be effective in rheumatoid arthritis patients with intolerance or inadequate response to first-generation JAKi. It is already apparent that a clear need exists for a JAK-IR trial to give guidance in those difficult patients who are JAKi non-responders3.

Objectives

To evaluate real world efficacy of a second-generation JAK1-selective JAKi UPA in single-center cohort of RA patients who had discontinued first-generation JAKi.

Methods

Patients with RA who had discontinued tofacitinib and/or baricitinib due to inadequate response or intolerance, regardless of whether they had used bDMARDs or not, were eligible for the study if they had received UPA by October 2021 and had been followed up for at least 12 weeks. Endpoints were Kaplan-Meier survival rate with inadequate response or intolerance as reasons for discontinuation, various disease activity assessments (DAS28-ESR, SDAI, CDAI, etc.), and patient reported outcomes (visual analogue scales (VASs) such as pain and stiffness, HAQ-DI, FACIT-Fatigue Scale, etc.) at 12 weeks. In addition, the reasons for discontinuation were investigated.

Results

Fifty-one patients were included in the study, all of whom had D2T RA and had used at least one bDMARD as well as JAKi. The mean (median) age was 72.7 (77) years, disease duration 18.0 (17) years, number of bDMARDs used 3.34 (3), number of JAKi used 1.3(1), 5 patients with methotrexate, 6 patients with prednisolone, and DAS28-ESR 3.83 (3.9). At 12 weeks, the overall survival rate was 94% (94.6% in 37 cases used as 2nd JAKi and 92.9% in 14 cases used as 3rd JAKi). For reference, there was no significant difference from the 100% of the 15 cases used as the 1st JAKi (P=0.49). DAS28-ESR <3.2 and <2.6 were achieved in 60.8% and 29.4%, VASs for pain and stiffness decreased by a mean of 12.9 mm (9 mm) and 12.1 mm (7 mm), respectively, and FACIT-Fatigue scale improved by a mean of 3.0 (1). The reasons for discontinuation in the three patients were inadequate efficacy in two and leg cramps due to venous thromboembolism in one.

Conclusion

UPA is more selective for JAK1 than first generation JAKi, and is expected to reduce adverse reactions caused by inhibition of JAK family members other than JAK1. The present study suggests that UPA is effective and well tolerated, regardless of the number and type of first-generation JAKi used in the past, albeit for a short period of time. Limitations include the small number of cases and the short time frame for discussing adverse reactions.

References

[1]Smolen JS, Landewé BM, Bijlsma WJ et al., EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2019 update. Ann Rheum Dis 2020;79:685–699.

[2]Christopher JE, Ruta S, Vishvas G et al. A Matching-Adjusted Indirect Comparison of Upadacitinib Versus Tofacitinib in Adults with Moderate-to-Severe Rheumatoid Arthritis. Rheumatol Ther 2021; 8:167–181.

[3]Peter Nash, Clinical use of Jak 1 inhibitors for rheumatoid arthritis. Rheumatology, Volume 60, Issue Supplement_2, May 2021, Pages ii31–ii38

Disclosure of Interests

None declared

Superomedial pedicle skin-reducing mastectomy in ptotic and large-sized breasts with two-stage reconstruction through transaxillary video-assisted technique: An effective surgical and anesthetic approach

Introduction

Skin-reducing mastectomy has been applied to several surgical techniques in which subcutaneous mastectomy is associated with various types of skin reduction, with preservation of a lower dermal flap to reinforce the inferior lateral seat of an implant. The aim of the study is to present a case series of patients with pendulous/ptotic and/or large-sized breasts treated for breast cancer at the Breast Surgery Unit of Istituto Nazionale Tumori IRCCS Fondazione "G. Pascale", Naples, Italy, with the superomedial pedicle skin-reducing mastectomy technique, two-stage reconstruction, and transaxillary video-assisted technique, when a postoperative radiotherapy was indicated. We verified its effectiveness by discussing its results, especially in patients who are candidates for postmastectomy radiotherapy.

Materials and methods

A single-center retrospective study was performed between January 2020 and March 2021 on a prospectively filled database of conservative mastectomies. Of the 64 patients who underwent nipple/skin-sparing mastectomies in the mentioned period, 17 (mean age 46 years, range 30-62 years) were treated with superomedial pedicle skin-reducing mastectomy, with two-stage breast reconstruction through transaxillary video-assisted replacement expander with definitive prosthesis and contralateral symmetrization, selected for postmastectomy radiotherapy.

Results

We had only three minor complications. No flap necrosis, no infections, no breast seromas, and no reconstructive failures were observed. During follow-up of the patients treated with video-assisted reconstruction, there were no cases of infection, hematoma, implant rupture, or suture dehiscence in the reconstructed breast.

Discussion

Skin-reducing mastectomy with superomedial pedicle is a safe and reliable procedure to treat breast cancer in selected patients, i.e., those with pendulous/ptotic and or large-sized breasts. Particularly, in patients who undergo postmastectomy radiotherapy, the two-stage reconstruction with video-assisted transaxillary endoscopic approach can find its main indication, using incisions positioned far from the mammary region, offering numerous advantages.

A randomized, controlled trial of once-weekly teriparatide injection versus alendronate in patients at high risk of osteoporotic fracture: primary results of the Japanese Osteoporosis Intervention Trial-05

In this randomized, controlled trial, treatment with once-weekly subcutaneous injection of teriparatide for 72 weeks was found to be associated with a significant reduction in the incidence of morphometric vertebral fractures compared with alendronate in women with primary osteoporosis who were at high risk of fracture.

INTRODUCTION

To determine whether the anti-fracture efficacy of teriparatide is superior to that of alendronate, a prospective, randomized, open-label, blinded-endpoint trial was performed.

METHODS

Japanese women aged at least 75 years were eligible for the study if they had primary osteoporosis and were at high risk of fracture. Patients were randomly assigned in a 1:1 ratio to receive sequential therapy (once-weekly subcutaneous injection of teriparatide 56.5 μg for 72 weeks followed by alendronate for 48 weeks) or monotherapy with alendronate for 120 weeks. The primary endpoint was the incidence of morphometric vertebral fractures at 72 weeks (at the end of teriparatide treatment).

RESULTS

Between October 2014 and December 2017, 1011 patients (505 in the teriparatide group and 506 in the alendronate group) were enrolled. Of these, 778 patients (351 and 427, respectively) were included in the primary analysis. The incidence of morphometric vertebral fractures was significantly lower in the teriparatide group (56 per 419.9 person-years, annual incidence rate 0.1334) than in the alendronate group (96 per 553.6 person-years, annual incidence rate 0.1734), with a rate ratio of 0.78 (95% confidence interval 0.61 to 0.99, P = 0.04). In both groups, adverse events were most frequently reported in the following system organ classes: infections and infestations, gastrointestinal disorders, and musculoskeletal and connective tissue disorders.

CONCLUSION

Once-weekly subcutaneous injection of teriparatide significantly reduced the incidence of morphometric vertebral fractures compared with alendronate in women with primary osteoporosis who were at high risk of fracture.

TRIAL REGISTRATION

jRCTs031180235 and UMIN000015573, March 12, 2019.

AB0252 EFFICACY OF A SECOND JANUS KINASE INHIBITOR THAT WAS SWITCHED FOR DIFFICULT-TO-TREAT RA IN CLINICAL PRACTICE

Background:

In clinical practice, when refractory rheumatoid arthritis (RA) is present, of which the definition implies previous use of at least two biologic disease-modifying antirheumatic drugs (bDMARDs) (generally tumour necrosis factor inhibitors (TNFis)), the next treatment choice often made is a bDMARD of another class (non-TNFis) [1]. However, patients who are inadequately responding to bDMARDs need new treatment options because subsequent bDMARDs treatment reduces their response [2]. Janus Kinase inhibitors (JAKis) are the first targeted synthetic DMARDs (tsDMARD) licensed for the treatment of RA with comparable efficacy to bDMARDs. Unlike the single cytokine targeting approach of bDMARDs, JAKis are specifically designed to inhibit intracellular signalling molecules common to the receptors of multiple inflammatory cytokines implicated in RA pathogenesis. The choice of therapeutic agents for refractory RA is increasing, and its efficacy is expected. On the other hand, it is also true that some patients discontinued JAKis at a rate that cannot be overlooked because of insufficient efficacy. Difficult-to-treat (D2T) RA is defined as refractory to two or more b/ts DMARDs with different mechanisms of action, with active and progressive disease, as published by Eular(3)

Objectives:

To evaluate real world efficacy of approved JAKis switching in patients with D2T RA who were unable to control their disease activity due to insufficient efficacy despite the sequential use of multiple bDMARDs and JAKis, focusing on the drug retention rate.

Methods:

In our hospital, RA was diagnosed according to the 1987 or 2010 classification criteria, and when two or more bDMARDs (including both TNFis and non-TNFis) were inadequately effective, it was defined as D2T RA. We retrospectively investigated patients who switched to JAKis for D2T RA. The drug retention rate was investigated by the Kaplan-Meier method, and the difference was tested by the Logrank test.

Results:

The 1-year retention rate of JAKis for D2T RA was 50.8% in TOF 38 cases [28 women, age average 70.2 years, disease duration average 12.4 years, past bDMARDs use average 3.5 drugs, MTX combination 9 cases, DAS28 ESR average 4.11] and 66.3% in BAR 35 cases [26 cases, 73.0 years old, 14.8 years, 4.17 agents, 9 cases, 3.68], and there was no significant difference (P = 0.30). Among them, there were 17 cases [11 cases, 70.6 years old, 13.5 years, 4.18 drugs, 2 cases, 3.65] of switching between JAKis, all of which were switching from TOF to BAR. The 1-year retention rate was 45.8% [reason for discontinuation: insufficient effect in 3 cases, adverse events in 6 cases], which was not significantly different but tended to be lower than 72.7% [reason for discontinuation: insufficient effect in 1 case, adverse event in 2 cases, patient’s convenience in 1 case] in 16 patients [13 cases, 76.3 years old, 17.1 years, 3.19 drugs, 7 cases, 3.69] who received BAR as the first JAKi for D2T RA patients (P = 0.089).

Conclusion:

Although the number of cases is small in the retrospective survey, it is suggested that the retention rate of BAR switched to D2T RA may be slightly lower in patients with a history of TOF discontinuation due to insufficient efficacy than in JAKi naive patients. It is expected that the number of new JAKi usage cases will increase in the future, and it is necessary to consider switching between other JAKis in addition to switching from BAR to TOF.

References:

[1]Smolen JS, Landewe R, Bijlsma J et al. EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2016 update. Ann Rheum Dis 2017;76:960_77.

[2]Rendas-Baum R, Wallenstein GV, Koncz T et al. Evaluating the efficacy of sequential biologic therapies for rheumatoid arthritis patients with an inadequate response to tumor necrosis factor-α inhibitors. Arthritis Res Ther 2011;13:R25.

[3]Nagy G, et al. EULAR definition of difficult-to-treat rheumatoid arthritis. Ann Rheum Dis 2021;80:31–35. doi:10.1136/annrheumdis-2020-217344.

Disclosure of Interests:

None declared

POS0088 EFFICACY OF JANUS KINASE INHIBITORS FOR DIFFICULT-TO-TREAT RA IN CLINICAL PRACTICE

Background:

In 20-30% of rheumatoid arthritis (RA) patients, the first biologic disease-modifying antirheumatic drugs (bDMARDs) (generally tumour necrosis factor inhibitors (TNFis)) is ineffective, and among the patients who do respond to therapy, 20% is faced with secondary ineffectiveness within the first 2 years of treatment [1]. In practice, when refractory RA is present, of which the definition implies previous use of at least two bDMARDs (generally TNFis), the next treatment choice often made is a bDMARD of another class (non-TNFis) [2]. On the other hand, patients who are inadequately responding to bDMARDs need new treatment options because subsequent bDMARD treatment reduces their response [3]. Janus Kinase inhibitors (JAKis) are the first targeted synthetic DMARDs (tsDMARD) licensed for the treatment of RA with comparable efficacy to bDMARDs. Unlike the single cytokine targeting approach of bDMARDs, JAKis are specifically designed to inhibit intracellular signalling molecules common to the receptors of multiple inflammatory cytokines implicated in RA pathogenesis.

Objectives:

Difficult-to-treat (D2T) RA is defined as refractory to two or more b/ts DMARDs with different mechanisms of action, with active and progressive disease, as published by Eular(4). We evaluated real world efficacy of approved JAKis and factors that may help to continue them in patients with D2T RA.

Methods:

Patients who had inadequate response to two or more bDMARDs (including both TNFis and non-TNFis) at our hospital by December 2019 were defined as D2T RA, and patients who switched to JAKis were retrospectively investigated. The drug retention rate was determined by Kaplan-Meier method, and the difference was tested by Logrank test. Multiple regression analysis was used as the statistical method to predict continuation of JAKis for more than 1 year, with patient background (age, gender, during the disease, number of bDMARDs used, with or without methotrexate and/or glucocorticoids, disease activity score assessing 28 joints using erythrocyte sedimentation rate’ presence of rheumatoid factor/anti-CCP antibody, matrix metalloproteinase 3 value, Health Assessment Questionnaire disability index) at the time of initiation as an explanatory variable.

Results:

A total of 915 bDMARDs had been administered to 394 RA patients. The retention rate of bDMARDs and the number of bDMARDs used were 89.3% and 1.48 bDMARDs at 1 year, 67.7% and 2.27 bDMARDs at 5 years, and 52.0% and 3.15 bDMARDs at 10 years, respectively. The retention rate of JAKis at 1 year was 60.2% in 65 patients with tofacitinib (TOF) and 67.2% in 70 patients with baricitinib (BAR) (P=0.38). Among them, the drug retention rate in D2T RA patients was 50.8% in 38 TOF patients and 66.3% in 35 BAR patients with no significant difference (P=0.30). There were no patient background factors that significantly predicted continuation at 1 year for any JAKis.

Conclusion:

Despite the limited number of patients and the retrospective nature of the study, TOF and BAR were shown to be effective options for D2T RA, regardless of patient background such as disease activity or number of bDMARDs used. Other JAKis and switches between JAKis need to be investigated in the future.

References:

[1]Schaeverbeke T, Truchetet ME, Kostine M et al. Immunogenicity of biologic agents in rheumatoid arthritis patients: lessons for clinical practice. Rheumatology 2016;55:210_20.

[2]Smolen JS, Landewe R, Bijlsma J et al. EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2016 update. Ann Rheum Dis 2017;76:960_77.

[3]Rendas-Baum R, Wallenstein GV, Koncz T et al. Evaluating the efficacy of sequential biologic therapies for rheumatoid arthritis patients with an inadequate response to tumor necrosis factor-α inhibitors. Arthritis Res Ther 2011;13:R25.

[4]Nagy G, et al. EULAR definition of difficult-to-treat rheumatoid arthritis. Ann Rheum Dis 2021;80:31–35. doi:10.1136/annrheumdis-2020-217344.

Disclosure of Interests:

None declared

Occurrence and clinical course of peri-stent contrast staining: comparison between second-generation drug-eluting stents and third generation drug-eluting stents

Background

Peri-stent contrast staining (PSS) has been reported to be associated with very late stent thrombosis.

The aims of this study was to compare the occurrence rate of PSS between second generation drug-eluting stents (2nd DES) and third generation drug-eluting stents (3rd DES), and to identify clinical characteristics associated with PSS.

Methods and results

This study comprised 1899 patients with 2493 de novo lesions treated with 2nd or 3rd DES from October 2015 to September 2018. Follow-up angiography was available for 1883 lesions (75.5%). There were 725 patients with 968 lesions treated with 2nd DES, and 716 patients with 915 lesions treated with 3rd DES. The occurrence of PSS, types of PSS, and VLST related to PSS were compared between 2nd and 3rd DES implantation. Mean follow-up period was 30±12 months. The occurrence rate of PSS and segmental type of PSS were similar between two groups (2nd DES vs. 3rd DES, 1.5% vs. 1.7%, p=0.73, 47% vs. 50%, p=0.85, and respectively). The VLST related to PSS occurred in only one case in 3rd DES group. (0% vs. 6.3%, p=0.33).

Conclusion

The occurrence rate of PSS and clinical course were similar between 2nd and 3rd DES.

Funding Acknowledgement

Type of funding source: None

Open-shell singlet diradicaloid difluoreno[4,3-b:3′,4′-d]furan and its radical cation and dianion

We report difluoreno[4,3-b:3′,4′-d]furan derivative as a stable open-shell singlet diradicaloid.

P5022Dual-energy CT was effective to evaluate of microvasculopathy in chronic thromboembolic pulmonary hypertension

Background

The existence of microvasculopathy in patients with chronic thromboembolic pulmonary hypertension (CTEPH) had been suggested. However, the impact of microvasculopathy for pathophysiology had been unknown. Recently dual-energy CT (DECT) can produce a sensitive iodine distribution map as blood perfusion in lung fields to quantify lung perfusion, also can suggest the existence of microvasculopathy according to poor subpleural perfusion which was published previously.

Methods

We retrospectively reviewed poor subpleural perfusion (defined as subpleural spaces either not or minimally perfused in all segments) and hemodynamics of 83 treatment-naïve CTEPH patients who underwent DECT from February 2014 to Jan 2019. Patients were divided according to poor subpleural perfusion: a microvasculopathy group (n=44) or a non-microvasculopathy group (n=39).

We assessed cardiopulmonary exercise test, right heart catheterization and DECT parameters as quantitative evaluation of pulmonary blood volume (PBV). PBV was calculated as the average of entire lung iodine density.

Results

PBV value in non-microvasculopathy group showed significant inverse correlation with pulmonary vascular resistance (PVR) (y = 14236 x-1.028 r=−0.530, p<0.01).

PBV, SvO2, and %DLCO/VA were significantly lower (22.0 vs. 26.4, p<0.01, 61.3 vs. 66.0, p<0.01, and 59.2 vs 75.9 p<0.01), and systolic pulmonary arterial pressure, PVR, VE/VCO2 slope, BNP were higher (69.3 vs 60.6 p=0.04, 834 vs 586 p<0.01, 45.5 vs. 37.8, p=0.02, and 440 vs 122 p=0.04) in microvasculopathy group, while the other parameters were similar between the two groups.

Multivariate analysis revealed that %DLCO/VA was the only predictor of microvasculopathy (OR,0.895 [95% CI, 0.835 - 0.960]; P<0.01).

Conclusion

Pulmonary blood flow of patients in non-micorvasculopathy group showed inverse correlation with PVR. DECT was effective to assess the microvasculopathy in CTEPH. In our experience, less than 60% of non-operable CTEPH patients have microvasculopathy.