Characteristics of pediatric patients claimed with acute upper respiratory infection during otorhinolaryngology consultations: A descriptive study of a large Japanese medical claims database

This study aimed to clarify other diseases claimed simultaneously with acute upper respiratory infection (URI), antibiotic prescriptions, and examinations associated with infectious diseases in pediatric patients with acute URI insurance claims at otorhinolaryngology outpatient visits. Pediatric patients who visited an otolaryngology department between 2019 and 2021 and were definitively diagnosed with URI were selected using a large Japanese medical claims database. Patient backgrounds, antibiotic use, and examinations were descriptively evaluated. In total, 8010 patients were included in the analysis. The median number (interquartile range) of diseases claimed in the same month as acute URI was 4 (3-6). Only 519 (6.5 %) patients were claimed as acute URI alone. Regardless of the prescription of antibiotics, the most commonly redundantly claimed disease in these patients was allergic rhinitis, followed by acute bronchitis, acute sinusitis, and earwax impaction. The frequently prescribed antibiotics were third-generation cephalosporins, macrolides, and penicillins with extended-spectrum, including amoxicillin which was recommended by the Japanese manual; the proportion of patients with examinations was low (2.9-21.7 %). Among patients with acute URI, diagnoses requiring antibiotics were also claimed; therefore, when evaluating acute URI using the Japanese medical claims database, care must be taken in patient selection. Moreover, the implementation rate of examinations necessary for diagnosis was low, so there is an urgent need to develop an environment where examinations can be conducted in outpatient settings.

Effect of influenza vaccine subsidies for older adults on vaccination coverage and mortality before and during the COVID-19 pandemic: an ecological study in Japan

OBJECTIVE

We aimed to determine how municipal subsidies for seasonal influenza vaccines for the elderly affected vaccination coverage and health outcomes and how responses to vaccine prices changed during the COVID-19 pandemic.

STUDY DESIGN AND METHODS

This ecological study includes 1245 municipalities in Japan between 2019 and 2020. Fixed-effects regression analysis was performed to evaluate the effect of influenza vaccine cost subsidy for people aged 65 years or older on vaccination coverage, all-cause mortality, and influenza-related mortality.

RESULTS

The vaccination rate increased when patients' copayments decreased, and reducing the copayment by 1000 Japanese Yen (JPY) was estimated to increase the vaccination rate by 6.3% (95% confidence interval [CI] 4.5-8.2%) in the adjusted model. When examining the additional effect of a zero price compared to a nearly zero price, we found that a zero price increased the immunization rate by 6.4% (95% CI 1.4-11.5%). The effect of copayment on the increase in vaccination coverage was significantly lower during the pandemic than in the pre-pandemic period. The municipal and prefectural analyses found no association between influenza vaccine copayments and all-cause, influenza, or pneumonia mortality.

CONCLUSION

Cost subsidies and the zero-price effect were shown to increase vaccination coverage but were not associated with relevant mortality measures. Although the impact was attenuated under pandemic conditions, cost subsidy effectively increases the vaccination rate.

Trends in teicoplanin loading dose implementation from 2010 to 2019 and evaluation of safety and efficacy factors: a retrospective cohort study based on a Japanese administrative claims database

BACKGROUND

The loading dose of teicoplanin (TEIC) is recommended for implementation. However, there is significant discrepancy between the dose settings in the package insert and, in the guidelines, and the actual status of loading doses in Japan is unclear. Furthermore, TEIC causes liver injury as side effect. Although the risk of developing liver injury has not been reported to be increased following a loading dose based on the guidelines, there is a lack of reports in large populations. Therefore, we evaluated the trend in the loading dose and factors affecting the efficacy and safety of TEIC administration.

METHODS

A Japanese administrative claims database was used in this study. Trends in loading doses were evaluated in target populations administered TEIC between 2010 and 2019. Patient characteristics were adjusted by propensity score matching based on the guideline group (total dose of 3 days > 1,600 mg) and non-guideline group (≤ 1,600 mg) of the loading dose. Finally, univariable and multivariable conditional logistic regression analysis was performed to evaluate factors affecting 30-day mortality and liver injury.

RESULTS

A total of 10,030 patients were selected based on these criteria. The proportion of loading doses based on the recommended guidelines showed an increase over time, regardless of the implementation of therapeutic drug monitoring (TDM), but especially so in cases where TDM was implemented, the loading doses were administered in accordance with the recommendations of the guidelines. Conditional logistic regression analysis showed a relationship between drug management and guidance fees (odds ratio [OR]: 0.45, 95% confidence interval [CI]: 0.36‒0.55), a reimbursement indicating pharmacist intervention, and a reduction in 30-day mortality. In addition, loading doses based on the recommended guidelines had no influence on liver injury, and other factors were not significantly associated with increased incidence of liver injury.

CONCLUSION

Thus, this study implies the benefits of pharmacological management as indicated by drug management and guidance fee and supports the implementation of loading doses based on the guideline on TEIC administration.

Risk of a second cancer and infection in patients with indolent B-cell lymphoma exposed to first-line bendamustine plus rituximab: A retrospective analysis of an administrative claims database

Bendamustine has a potent immunosuppressive effect because it causes T-cell lymphopenia, which might lead to a second primary malignancy (SPM) and would increase the risk of infection. Using the Medical Data Vision administrative claims database, we compared the cumulative incidence of SPM, infections within 6 months, and overall survival (OS) among untreated patients with indolent B-cell lymphomas (iBCL) who received rituximab-based chemotherapy between 2009 and 2020. Patients with grade 3b follicular lymphoma or a previous history of malignancy were excluded. Eligible 5234 patients were assigned to three cohorts: rituximab monotherapy (N = 780), RCHOP/RCVP/RTHPCOP (doxorubicin replaced with pirarubicin) (N = 2298), or bendamustine/rituximab (BR) (N = 2156). There were 589 recorded SPMs, of which myelodysplastic syndromes were the most common (1.7%). The cumulative incidence of SPM was significantly higher in patients treated with BR than in those treated with rituximab monotherapy (p < 0.01) or RCHOP/RCVP/RTHPCOP (p < 0.0001): the 5-year cumulative incidence function was 18.1%, 12.5%, and 12.9%, respectively. In the Fine-Gray subdistribution hazards model, BR showed a significantly higher cumulative incidence of SPM than RCHOP/RCVP/RTHPCOP (subhazard ratio, 1.33; 95% confidence interval [CI], 1.10-1.61). Furthermore, in sensitivity analysis, a nested case-control study using an entire cohort showed consistent results: the SPM odds ratios (95% CI) of first-line bendamustine, bendamustine after first-line, and any-line bendamustine were 1.43 (1.14-1.78), 1.26 (0.96-1.64), and 1.33 (1.09-1.62), respectively. Regarding infections, adjusted odds ratios (95% CI) of BR compared to RCHOP/RCVP/RTHPCOP were as follows: cytomegalovirus infection, 13.7 (4.88-38.4); bacterial pneumonia, 0.63 (0.50-0.78); and pneumocystis pneumonia, 0.24 (0.11-0.53). There was no significant difference in OS between RCHOP/RCVP/RTHPCOP and BR in patients with follicular, mantle cell, marginal zone, or lymphoplasmacytic lymphomas. In conclusion, treatment strategies that consider the risk of SPM and infections after chemotherapy are warranted in patients with iBCL.

Fabrication of cell-laden microbeads and microcapsules composed of bacterial polyglucuronic acid

In the past decades, the microencapsulation of mammalian cells into microparticles has been extensively studied for various in vitro and in vivo applications. The aim of this study was to demonstrate the viability of bacterial polyglucuronic acid (PGU), an exopolysaccharide derived from bacteria and composed of glucuronic acid units, as an effective material for cell microencapsulation. Using the method of dropping an aqueous solution of PGU-containing cells into a Ca²⁺-loaded solution, we produced spherical PGU microbeads with >93 % viability in the encapsulated human hepatoma HepG2 cells. Hollow-core microcapsules were formed via polyelectrolyte complex layer formation of PGU and poly-l-lysine, after which Ca²⁺, a cross-linker of PGU, was chelated, and this was accomplished by sequential immersion of microbeads in aqueous solutions of poly-l-lysine and sodium citrate. The encapsulated HepG2 cells proliferated and formed cell aggregates within the microparticles over a 14-day culture, with significantly larger aggregates forming within the microcapsules. Our results provide evidence for the viability of PGU for cell microencapsulation for the first time, thereby contributing to advancements in tissue engineering.

Effectiveness of Noncertified Pharmacist-Led Antimicrobial Stewardship Programs in a Medium-Sized Hospital Without an Infectious Disease Specialist: A Retrospective Pre-Post Study

Background

Few studies have reported the outcomes of antimicrobial stewardship programs (ASPs) implemented without infectious disease (ID) physician or pharmacist specialists. We implemented interventions that included providing antimicrobial optimization recommendations through a pharmacist-led team using prospective audit and feedback. This study evaluated different types of interventions and their impact on the outcomes of ASPs in a medium-sized hospital without ID specialists.

Methods

This retrospective pre-post study included adult inpatients treated with intravenous antimicrobials between April 2016 and March 2020. Outcome (eg, length of hospital stay [LOS], drug cost) and process measures (eg, type of intervention, length of therapy) were compared between 2 time periods: pre-ASP (April 2016-March 2018) and post-ASP (April 2018-March 2020).

Results

We included 5419 and 5634 patients in the pre- and post-ASP periods, respectively. The most common types of interventions were adjusting length of therapy (49.5%), additional laboratory tests (27.1%), antimicrobial change (16.2%), and dosage of antimicrobial (7.1%). After ASP implementation, LOS significantly decreased (14.8 vs 13.8 days, P < .01), along with the length of therapy, empirical use of antipseudomonal and anti-methicillin-resistant Staphylococcus aureus drugs, and number of days to de-escalation. No significant differences were noted in 30-day mortality, 30-day readmission, or de-escalation rates. On average, the antimicrobial cost per hospitalization decreased from US$173.03 to US$120.66.

Conclusions

Pharmacist-led ASP interventions that focus on the length of therapy have the potential to reduce LOS in hospitals without ID specialists. Overall, this study showed that ASPs can be effectively implemented in medium-sized hospitals without ID specialists.

Trends in Implementation of Loading Dose of Voriconazole from 2010 to 2019 and Influencing Factors of Loading Dose Based on a Japanese Administrative Claim Database: A Retrospective Cohort Study

A loading dose of voriconazole (VRCZ) is recommended to increase its blood concentration at an early stage. However, the trends in the implementation of the loading dose in VRCZ in Japan has not yet been clarified. In addition, although pharmacists play many important roles in antimicrobial stewardship, the effect of pharmacist intervention on the implementation of a loading dose of VRCZ has not yet been reported. Therefore, this study aimed to clarify the implementation of loading dose of VRCZ and the influencing factors of loading dose. This study used an administrative claims database that included patients who received injectable VRCZ between 2010 and 2019. The implementation of loading doses in the VRCZ was evaluated annually. Multivariate logistic regression analysis was performed to identify the factors influencing loading dose. Overall, 2197 patients were included. The implementation rate of the loading dose remained below 65% throughout the study period. Among medical fees that can be calculated through pharmacist intervention, only the infection prevention and control premium significantly increased the implementation of loading dose of VRCZ (odds ratio: 1.587, 95% confidence interval: 1.053-2.392). In conclusion, antifungal stewardship may have been promoted at medical institutions that established infection prevention and control. In the future, pharmacists will need to intervene more actively from the beginning of VRCZ administration.

Phenol-Grafted Alginate Sulfate Hydrogel as an Injectable FGF-2 Carrier

In the field of tissue engineering, fibroblast growth factor-2 (FGF-2) effectively regenerates damaged tissue and restores its biological function. However, FGF-2 readily diffuses and degrades under physiological conditions. Therefore, methods for the sustained and localized delivery of FGF-2 are needed. Drug delivery systems using hydrogels as carriers have attracted significant interest. Injectable hydrogels with an affinity for FGF-2 are candidates for FGF-2 delivery systems. In this study, we fabricated a hydrogel from phenol-grafted alginate sulfate (AlgS-Ph) and investigated its application to the delivery of FGF-2. The hydrogel was prepared under mild conditions via horseradish peroxidase (HRP)-mediated cross-linking. Surface plasmon resonance (SPR) measurements show that the AlgS-Ph hydrogel has an affinity for FGF-2 in accordance with its degree of sulfation. Conditions for the preparation of the AlgS-Ph hydrogel, including HRP and H₂O₂ concentrations, are optimized so that the hydrogel can be used as an injectable drug carrier. The hydrogel shows no cytotoxicity when using 10T1/2 cells as a model cell line. The angiogenesis assay shows that FGF-2 released from the AlgS-Ph hydrogel promotes the formation of blood vessels. These results indicate that the AlgS-Ph hydrogel is a suitable candidate for the FGF-2 carrier.

Cardiopulmonary arrest and in-hospital outcomes in young patients with acute myocardial infarction: insights from the Japanese nationwide registry

Background

Cardiopulmonary arrest (CPA) is the most serious presentation of acute myocardial infarction (AMI). However, the frequency and prognostic impact of CPA in young patients with AMI have been still unclear.

Objectives

This study aimed to characterize AMI in young patients who underwent primary percutaneous coronary intervention using large-scale nationwide all-comer registry data in Japan (J-PCI registry).

Methods

Data on risk factor profiles, clinical features, post-procedural complications, and in-hospital outcomes were reviewed within the J-PCI registry between 2014 and 2018.

Results

Among 213,297 patients with AMI, 23,985 (11.2%) were young (age, 20–49 years). Compared with the older group (age, 50–79 years; n=189,312), the young group included a higher number of men, smokers, patients with dyslipidemia, and patients with single-vessel disease, and a lower number of patients with hypertension and diabetes. Despite favorable clinical profiles, younger age was associated with a higher rate of presentation with CPA (Figure 1). Further, concomitant CPA was strongly associated with in-hospital mortality in the young group (Table 1).

Conclusions

Young patients with AMI presented a higher risk of CPA than older patients, which was strongly associated with in-hospital mortality.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): JSPS KAKENHI

Development of phenol-grafted polyglucuronic acid and its application to extrusion-based bioprinting inks

In this present work, we developed a phenol grafted polyglucuronic acid (PGU) and investigated the usefulness in tissue engineering field by using this derivative as a bioink component allowing gelation in extrusion-based 3D bioprinting. The PGU derivative was obtained by conjugating with tyramine, and the aqueous solution of the derivative was curable through a horseradish peroxidase (HRP)-catalyzed reaction. From 2.0 w/v% solution of the derivative containing 5 U/mL HRP, hydrogel constructs were successfully obtained with a good shape fidelity to blueprints. Mouse fibroblasts and human hepatoma cells enclosed in the printed constructs showed about 95% viability the day after printing and survived for 11 days of study without a remarkable decrease in viability. These results demonstrate the great potential of the PGU derivative in tissue engineering field especially as an ink component of extrusion-based 3D bioprinting.

A laboratory study of hydraulic fracturing at the brittle-ductile transition

Developing high-enthalpy geothermal systems requires a sufficiently permeable formation to extract energy through fluid circulation. Injection experiments above water’s critical point have shown that fluid flow can generate a network of highly conductive tensile cracks. However, what remains unclear is the role played by fluid and solid rheology on the formation of a dense crack network. The decrease of fluid viscosity with temperature and the thermally activated visco-plasticity in rock are expected to change the deformation mechanisms and could prevent the formation of fractures. To isolate the solid rheological effects from the fluid ones and the associated poromechanics, we devise a hydro-fracture experimental program in a non-porous material, polymethyl methacrylate (PMMA). In the brittle regime, we observe rotating cracks and complex fracture patterns if a non-uniform stress distribution is introduced in the samples. We observe an increase of ductility with temperature, hampering the propagation of hydraulic fractures close to the glass transition temperature of PMMA, which acts as a limit for brittle fracture propagation. Above the glass transition temperature, acoustic emission energy drops of several orders of magnitude. Our findings provide a helpful guidance for future studies of hydro-fracturing of supercritical geothermal systems.

Trends of the Use of Anti-methicillin-Resistant Staphylococcus aureus Agents in Japan Based on Sales Data from 2006 to 2015

Patterns of the use of anti-methicillin-resistant Staphylococcus aureus (MRSA) agents in Japan might be influenced by the launch of new anti-MRSA agents, the publication of relevant guidelines, and the increase in the number of generic medicines. However, as anti-MRSA agents are included in multiple anatomical therapeutic chemical classifications, such as glycopeptides and aminoglycosides, the trends of the use of individual anti-MRSA agents remain unclear. Here, we aimed to clarify the trends of anti-MRSA agent use in Japan from 2006 to 2015 based on sales data. Total anti-MRSA agent use was found to have significantly increased from 2006 to 2015 (P_{for trend} = 0.027, r = 0.00022). Individual trends for vancomycin (VCM), daptomycin, and linezolid (LZD) use showed significant increases, while those for arbekacin (ABK) and teicoplanin (TEIC) showed decreases. In addition, oral LZD use significantly increased, while there was no significant change in intravenous LZD use. The ratio of oral LZD use to total LZD use increased from 25.5% in 2006 to 39.9% in 2015. Meanwhile, TEIC and ABK use decreased, while VCM use increased, following the launch of generic medicines. These results might reflect the status of guideline compliance, the launch of new anti-MRSA agents, and the decline in the sales promotion of the original medicines. It is extremely important to investigate trends for the use of not only different antibiotic groups but also individual antibiotics to develop and implement antimicrobial resistance countermeasures.

Trends in Antipseudomonal Agent Use Based on the 2006 to 2015 Sales Data in Japan

Pseudomonas aeruginosa resistance is a major issue worldwide. Drug resistance is related to inappropriate antibiotic use. Because antipseudomonal agents have a wide spectrum, they must be used appropriately. The purpose of this study was to clarify the trends in antipseudomonal agent use in Japan based on sales data from 2006 to 2015. The total antipseudomonal agent use was increased significantly (r = 0.10, P_{for trend} = 0.00040). The proportion of fluoroquinolones use was the highest throughout the year, accounting for 88.6-91.4%. The use of piperacillin/tazobactam significantly increased. The increased use of these drugs may be due to the launch of higher doses and additional indications. On the other hand, for antipseudomonal agents, parenteral carbapenems use was 2.7-3.7%, but it has remained unchanged over the years. In Japan, permit and notification systems have been introduced to prevent the inappropriate use of parenteral carbapenems in medical institutions. It was speculated that these efforts suppressed the inappropriate use of parenteral carbapenems. This study clarified the trend of antipseudomonal agent use in Japan from 2006 to 2015. It is important to continue monitoring antipseudomonal agents use to conduct appropriate antimicrobial resistance measures.

Trends of Antifungal Use Based on Sales Data in Japan from 2006 to 2015

The detailed epidemiology of invasive mycoses and superficial mycoses has not been clarified in Japan. In addition, treatment options have increased because of novel antifungals and/or guidelines for fungal infection. In the present study, we aimed to clarify the trends of antifungal use in Japan from 2006 to 2015 based on sales data to serve as an alternative indicator of fungal infection trends. We found that the total antifungal use decreased over time (r = -0.057, P_{for trend} < 0.0001). Oral and parenteral use significantly decreased by 44.1% (r = -0.056, P_{for trend} < 0.0001) and 27.1% (r = -0.0012, P_{for trend} = 0.00061), respectively. The trend of antifungal use for superficial mycoses significantly decreased by 49.8% (r = -0.061, P_{for trend} < 0.0001). However, the trend of antifungal use for invasive mycoses was significantly increased by 19.9% (r = 0.0032, P_{for trend} = 0.00045). In Japan, the increase in the number of immunocompromised patients might be associated with the increase in the frequency of antifungal use for invasive mycoses. This is the first study to clarify the trends of antifungal use in Japan. Further research is needed to establish a continuous surveillance system to compare fungal infections between Japan and the world.

Observation of Coulomb-Assisted Nuclear Bound State of Ξ^{-}-^{14}N System

In an emulsion-counter hybrid experiment performed at J-PARC, a Ξ^{-} absorption event was observed which decayed into twin single-Λ hypernuclei. Kinematic calculations enabled a unique identification of the reaction process as Ξ^{-}+^{14}N→_{Λ}^{10}Be+_{Λ}^{5}He. For the binding energy of the Ξ^{-} hyperon in the Ξ^{-}-^{14}N system a value of 1.27±0.21  MeV was deduced. The energy level of Ξ^{-} is likely a nuclear 1p state which indicates a weak ΞN-ΛΛ coupling.

The Trend for Antibiotic Use for Clostridioides (Clostridium) difficile Infection in Japan

In Japan, there is no national surveillance study of Clostridioides (Clostridium) difficile infection (CDI), and details about the epidemiology and treatment status of CDI are unknown. Additionally, clinical practice guidelines (CPGs) for CDI are published by four different institutions. All CPGs recommend that the antimicrobials, vancomycin (VCM) and metronidazole (MNZ), should be selected according to disease severity. However, the trends for VCM and MNZ use in Japan remain unclear. Therefore, this study was aimed at clarifying the secular trends for VCM and MNZ use based on sales data from 2006 to 2015 and discussing its impact on CDI status and drug costs. This is the first study to clarify the antibiotic use trends for CDI treatment. We found that the total use increased over time (r = 0.0013, P_{for trend} < 0.0001). While VCM use significantly decreased (r = -0.0003, P_{for trend} = 0.0002), MNZ use increased (r = 0.0017, P_{for trend} < 0.0001). These results show that although treatment for CDI was in line with CPGs, CDI incidence might be on an increasing trend. Additionally, despite the increased total use, the total drug costs decreased by 55% ($ 25 million) from 2006 to 2015. It was also surmised that CDI treatment in compliance with CPGs would lead to a reduction in drug costs. Hence, to understand the epidemiology of CDI, it is important to continuously investigate the use of drugs used for CDI therapy.

Efficacy of guselkumab in a subpopulation with pustulotic arthro-osteitis through week 52: an exploratory analysis of a phase 3, randomized, double-blind, placebo-controlled study in Japanese patients with palmoplantar pustulosis

Background

Previous studies of guselkumab have demonstrated clinical benefits in patients with plaque‐type psoriasis, generalized pustular psoriasis, erythrodermic psoriasis and palmoplantar pustulosis (PPP).

Objective

The aim of this exploratory analysis of a double‐blind, multicenter, placebo‐controlled, phase 3 study in Japanese patients with PPP was to evaluate the efficacy of guselkumab in the subset of patients with pustulotic arthro‐osteitis (PAO).

Methods

Patients were randomized to receive guselkumab 100 or 200 mg at weeks 0, 4, 12 and every 8 weeks, or placebo with cross‐over to guselkumab 100 or 200 mg at week 16 (placebo group). Efficacy endpoints were changes from baseline in magnetic resonance imaging (MRI) score, EuroQOL‐5 dimensions (EQ‐5D) index score, EQ‐5D pain/discomfort dimension score and C‐reactive protein (CRP, mg/L) level in all PAO patients through week 52. Data from both guselkumab groups were combined and presented as results for a single overall guselkumab group.

Results

Among 159 patients with PPP, 66 with PAO were randomized across treatment groups. For patients with MRI data for all regions assessed, the proportion of patients in the guselkumab group with PAO characterized as severe decreased from 23.8% (10/42) at baseline to 5.4% (2/42) at week 52. The mean (SD) change from baseline at week 52 in EQ‐5D index score was 0.20 (0.17) among PPP patients with PAO and 0.15 (0.17) among those without PAO in the guselkumab group. Among all PAO patients, the proportions with an EQ‐5D pain/discomfort dimension score of no or slight pain/discomfort in the guselkumab group increased from baseline to week 52 [33.3% (7/21) vs. 87.5% (35/40)]. The mean (SD) CRP levels decreased in all PAO patients in the guselkumab group at week 52 compared to baseline [−1.71 (8.16) mg/L].

Conclusion

Guselkumab treatment showed beneficial outcomes for PAO signs and symptoms in Japanese patients with PPP.

Abstract P4-08-16: Validation of the AJCC eighth edition prognostic stage compared with the anatomic stage for breast cancer with a Japanese single-institutional cohort

Background: The American Joint Committee for Cancer (AJCC) 8th edition cancer staging system for breast cancer incorporated biologic factors in addition to the 7th edition anatomic stage. We analyzed how the new AJCC 8th edition prognostic stage refined its stratification compared with the anatomic stage.

Methods: We reviewed the data of 4,134 patients with stage I to III breast cancer who underwent surgery at Tokyo Metropolitan Komagome Hospital between 2000 and 2016. The anatomic stage and prognostic stage were re-staged according to the AJCC 8th edition staging manual. Patients who received neoadjuvant chemotherapy or had bilateral breast cancer and those with unknown clinicopathologic factors were excluded. The 21-gene Oncotype DX breast recurrence score was not used for staging in this study.

Results: A total of 2,469 patients with a median follow-up of 4.7 years (range 0.1-15.5 years) were identified. According to the anatomic stage, there were 1,259 patients of stage IA, 132 of IB, 591 of IIA, 206 of IIB, 130 of IIIA, 14 of IIIB and 73 of IIIC. According to the prognostic stage, there were 1,610 patients of stage IA, 331 of IB, 236 of IIA, 73 of IIB, 85 of IIIA, 43 of IIIB and 27 of IIIC. Sixty-four patients (2.6%) could not be assigned using the new staging system for the presence of micrometastases in lymph nodes with tumors larger than 2 cm. The 5-year disease-free survival (DFS) rates according to the anatomic stage were 97.4% for stage IA, 97.1% for IB, 95.8% for IIA, 86.5% for IIB, 77.9% for IIIA, 49.2% for IIIB and 54.9% for IIIC. According to the prognostic stage, the 5-year DFS rates were 97.9% for stage IA, 92.9% for IB, 91.2% for IIA, 79.8% for IIB, 67.4% for IIIA, 53.3% for IIIB and 38.7% for IIIC. Compared with the AJCC anatomic stage, the prognostic stage was increased in 148 patients (6.2%) and decreased in 808 patients (32.8%). For those in whom the stage changed, the change was by one stage up or down in 463 (19.3%), by 2 stages up or down in 401 (16.7%) and by 3 stages up or down in 92 (3.8%). Of the 1,842 patients with hormone receptor (HR)-positive and human epidermal growth factor 2 (HER2)-negative (HR+/HER2-) disease, 40.5% (745/1842) of cases were downstaged, and 0.7% (1/1842) were upstaged.

Discussion: The AJCC 8th edition prognostic staging system provided more refined stratification than the anatomic stage. In the Japanese cohort, the proportion of the downstaging rate was higher than the upstaging rate, and the prognostic evaluation of HR+ patients in particular was improved.

Citation Format: Miyamoto H, Saita C, Onishi M, Goto R, Iwamoto N, Honda Y, Aruga T. Validation of the AJCC eighth edition prognostic stage compared with the anatomic stage for breast cancer with a Japanese single-institutional cohort [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-08-16.

Estimating the Net Utility Gains Among Donors and Recipients of Adult Living Donor Kidney Transplant

OBJECTIVES

Living donor kidney transplant relieves the disease burden of patients with end-stage renal disease but may shorten donor life expectancy; however, their quality of life (QOL) is preserved. Nevertheless, the magnitude of the net gain of this procedure is unknown. We evaluated the QOL of both donors and recipients concurrently and calculated the net utility gain.

METHODS

We recruited 210 subjects who visited the kidney transplantation clinic of a university hospital. Subjects were asked to complete the 5-level EQ-5D-based questionnaire, and patient characteristics were extracted from their medical records. We performed multivariate tobit models analysis to evaluate the QOL change caused by transplant surgery and subsequently ran computational simulations to determine the net utility gains of donors and recipients. We also performed sensitivity analyses.

RESULTS

After excluding 16 answers with missing data, we analyzed 203 answers in total. After the transplant surgery, recipients gained 0.07 in utility value while donors lost 0.04. In the net utility analysis, we found that the quality-adjusted life years gained ranged from 7.2 to 7.8 in the most favorable case observed in the combination of middle-aged recipients and elderly donors. Assuming no utility discount, the most favorable combination was that with older donors and younger recipients.

CONCLUSIONS

These findings indicated that the QOL improvement in recipients was larger than the loss among donors. When calculating the net utilities, a combination of middle-aged recipients and elderly donors yielded the largest net utility, but this was likely derived from assumption in the discount of QOL.

Abstract P3-01-09: Re-evaluating the “10% rule” for sentinel lymph node biopsy with radioactive method in breast cancer; a single institutional retrospective study

Background:

When multiple radioactive sentinel lymph nodes (SLNs) are present during sentinel lymph node biopsy (SLNB), excision of those SLNs with &gt;10% radioactive count per minute (high-CPM) of the most radioactive node (“10% rule”) has been proposed. Although this “10% rule” may avoid excessive removal of SLNs,the risk of false negative and remnant positive SLNs in the patients who have SLNs with &lt;10% CPM (low-CPM) remain unclear. The purpose of this analysis is to determine the clinical validity of this “10% rule” for early breast cancer patients.

Method:

We reviewed the records of successful SLNBs using the radioisotope (RI) method performed between January 2001 and December 2016 in our institution. The radioactive count from each excised SLN was measured. Non-radioactive lymph nodes were excluded from this analysis. All SLNs were pathologically assessed by 2mm serial section with hematoxylin and eosin staining.

Results:

In the 3,043 patients with successful SLNB,the median number of radioactive SLNs removed was 2 (mean, 1.8; range, 1-10) and 599 patients (19.7%) had SLNs with low-CPM. The total number of radioactive SLNs was 5,472, and 875 (16.0%) out of 5,472 SLNs were low-CPM. Sixty-one (7.0%) out of these 875 SLNs with low CPM in 56 patients (1.8%) had metastatic disease by pathological assessment. The number of metastatic SLN with low-CPM was one in 51 patients and two in 5 patients. Nineteen patients (0.6%) had no metastatic lesion in SLNs with high-CPM.

Discussion and Conclusions:

If SLNB was performed by RI method alone with “10% rule”, false negative rate increased by 0.6% and underestimation increased up to 1.8%. Furthermore, 19.7% of the patients have the benefit of avoiding excessive removal of SLNs.Considering the risk and benefit, “10% rule” is a high validitymethod to capture metastatic SLNs even in the setting that ALND will not be performed.

Citation Format: Miyamoto H, Aruga T, Onishi M, Goto R, Iwamoto N, Idera N, Horiguchi K, Honda Y. Re-evaluating the “10% rule” for sentinel lymph node biopsy with radioactive method in breast cancer; a single institutional retrospective study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-01-09.

Abstract P3-05-17: The numbers of Foxp3 positive cells in simultaneous bilateral breast cancer

Background

Evasion of the immune system is one of the hallmarks of malignant tumors, and recently blocking of such evasion has been used in clinical practice for the treatment of some types of cancers. Recruitment of regulatory T cells (Tregs), which express the specific marker Foxp3, is an established mechanism of escaping from the immune system. In breast cancer, it has been reported that the number of Tregs differs widely among breast cancer subtypes, and that patients who have many Tregs around the tumor tend to have a poor prognosis. However, the factors that are important for the recruitment of Tregs are not well known. Thus, factors that depend on the host (e.g., age or comorbidity), on the tumor (e.g., subtype, grade, or stage), or on measurement error might be the cause of the observed differences in the number of Tregs. In this study, we investigated the numbers of Tregs in simultaneous bilateral breast cancer patients in order to determine the factors that influence the recruitment of Tregs, while excluding differences in individuals as much as possible.

Material and methods

Patients who had breast cancer in both breasts and who underwent simultaneous surgery between January 2005 and September 2015 at two institutions were enrolled in this study. Patients who underwent primary systemic therapy who were diagnosed with ductal carcinoma in situ, or who were stage IV were excluded. The average numbers of Foxp3-positive (Foxp3+cells) were determined from scores of five high-power fields (HPFs). The association between the difference in Foxp3+ cell number between each breast in a single individual and clinicopathological features was examined.

Results

Seventy patients were included in this study. Their ages ranged from 39-85 (median 54) years old. Ninety five percent of the tumors were invasive ductal carcinoma non-special type. Eighty eight (62.9%), 43 (30.7%), and 9 (6.4%) of the tumors were T1, T2, and ≥T3, respectively, and 102 (72.9%) of the tumors were node-negative. Regarding nuclear grade (NG), 104 (74.3%), 21 (22.1%), and 7 (5%) of the tumors were NG1, 2, and 3, respectively. As for subtype, 124 (88.6%), 9 (6.4%), and 7 (5%) were ER-positive and HER2-negative(ER+/HER2-), ER-positive or negative and HER2-negative(ER±/HER2+), and ER-negative and HER2-negative(ER-/HER2-), respectively. The numbers of Foxp3+ cells ranged from 0 to 39.8 (median 3.3)/HPF, and difference in Foxp3+ cell number between each breast in a single individual ranged from 0 to 34 (median 3.9)/HPF.

Differences in tumor size and node status in individuals did not impact on the number of Foxp3+ cells. However, the number of Foxp3+ cells in tumors that were NG3 (P=0.00098) or ER±/HER2+ or ER-/HER2- type (P=0.00586) were statistically significantly increased compared with tumors that were NG1/2 or ER+/HER2- type in the same host.

Furthermore, the difference of Foxp3+ cells between each tumor in a single individual were quite small regarding tumor size and node status in 53 patients who had similar NG and subtype tumors in both breasts.

Conclusions

The number of Foxp3+ cells showed no relationship with tumor size, or lymph node status in simultaneous bilateral breast cancer patients. High NG, ER±/HER2+ or ER-/HER2- type of the tumor were involved with enhancement of the recruitment of Tregs.

Citation Format: Goto R, Hirota Y, Aruga T, Horiguchi S, Tazawa S, Nakamura S, Takimoto M. The numbers of Foxp3 positive cells in simultaneous bilateral breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-05-17.

De novo sequencing of highly modified therapeutic oligonucleotides by hydrophobic tag sequencing coupled with LC-MS

Correct sequences are prerequisite for quality control of therapeutic oligonucleotides. However, there is no definitive method available for determining sequences of highly modified therapeutic RNAs, and thereby, most of the oligonucleotides have been used clinically without direct sequence determination. In this study, we developed a novel sequencing method called 'hydrophobic tag sequencing'. Highly modified oligonucleotides are sequenced by partially digesting oligonucleotides conjugated with a 5'-hydrophobic tag, followed by liquid chromatography-mass spectrometry analysis. 5'-Hydrophobic tag-printed fragments (5'-tag degradates) can be separated in order of their molecular masses from tag-free oligonucleotides by reversed-phase liquid chromatography. As models for the sequencing, the anti-VEGF aptamer (Macugen) and the highly modified 38-mer RNA sequences were analyzed under blind conditions. Most nucleotides were identified from the molecular weight of hydrophobic 5'-tag degradates calculated from monoisotopic mass in simple full mass data. When monoisotopic mass could not be assigned, the nucleotide was estimated using the molecular weight of the most abundant mass. The sequences of Macugen and 38-mer RNA perfectly matched the theoretical sequences. The hydrophobic tag sequencing worked well to obtain simple full mass data, resulting in accurate and clear sequencing. The present study provides for the first time a de novo sequencing technology for highly modified RNAs and contributes to quality control of therapeutic oligonucleotides. Copyright © 2016 John Wiley & Sons, Ltd.

Stainless-Steel Ball-Milling Method for Hydro-/Deutero-genation using H2O/D2O as a Hydrogen/Deuterium Source

A one-pot continuous-flow method for hydrogen (deuterium) generation and subsequent hydrogenation (deuterogenation) was developed using a stainless-steel (SUS304)-mediated ball-milling approach. SUS304, especially zero-valent Cr and Ni as constituents of the SUS304, and mechanochemical processing played crucial roles in the development of the reactions.

Gold-Catalyzed Benzylic Azidation of Phthalans and Isochromans and Subsequent FeCl3-Catalyzed Nucleophilic Substitutions

The benzylic positions of the phthalan and isochroman derivatives (1) as benzene-fused cyclic ethers effectively underwent gold-catalyzed direct azidation using trimethylsilylazide (TMSN3) to give the corresponding 1-azidated products (2) possessing the N,O-acetal partial structure. The azido group of the N,O-acetal behaved as a leaving group in the presence of catalytic iron(III) chloride, and 1-aryl or allyl phthalan and isochroman derivatives were obtained by nucleophilic arylation or allylation, respectively. Meanwhile, a double nucleophilic substitution toward the 1-azidated products (2) occurred at the 1-position using indole derivatives as a nucleophile accompanied by elimination of the azido group and subsequent ring opening of the cyclic ether nucleus produced the bisindolylarylmethane derivatives.

Parallel chemical switches underlying pollinator isolation in Asian Mitella

Floral scents are among the key signals used by pollinators to navigate to specific flowers. Thus, evolutionary changes in scents should have strong impacts on plant diversification, although scent-mediated plant speciation through pollinator shifts has rarely been demonstrated, despite being likely. To examine whether and how scent-mediated plant speciation may have occurred, we investigated the Asimitellaria plant lineage using multidisciplinary approaches including pollinator observations, chemical analyses of the floral scents, electroantennographic analyses and behavioural bioassays with the pollinators. We also performed phylogenetically independent contrast analyses of the pollinator/floral scent associations. First, we confirmed that the pairs of the sympatric, cross-fertile Asimitellaria species in three study sites consistently attract different pollinators, namely long-tongued and short-tongued fungus gnats. We also found that a stereoisomeric set of floral volatiles, the lilac aldehydes, could be responsible for the pollinator specificity. This is because the compounds consistently elicited responses in the antennae of the long-tongued fungus gnats and had contrasting effects on the two pollinators, that is triggering the nectaring behaviour of long-tongued fungus gnats while repelling short-tongued fungus gnats in a laboratory experiment. Moreover, we discovered that volatile composition repeatedly switched in Asimitellaria between species adapted to long-tongued and short-tongued fungus gnats. Collectively, our results support the idea that recurrent scent-mediated speciation has taken place in the Asimitellaria–fungus gnat system.

Abstract P2-10-04: The clinicopathological features of androgen receptor expression in primary HER2-positive breast carcinomas

Background: Human epidermal growth factor receptor 2 (HER2)-positive breast carcinomas are aggressive subtypes associated with a variable response to systemic therapies. HER2-positive breast carcinomas are not homogeneous, and it has been reported that androgen receptor (AR) signaling is an important determinant of cell growth and relation with HER3 expression. The aim of this study was to investigate the clinicopathological significance of AR expression in primary HER2-positive breast carcinomas.

Patients and Methods: 102 primary HER2-positive breast tumor samples were obtained from patients operated on at the Cancer and Infectious Disease Center, Tokyo Metropolitan Komagome Hospital from 2001 to 2010. 92 tumors were IHC (HercepTest) score 3, whereas 10 were IHC score 2 and FISH- positive. We evaluated AR using immunohistochemistry. Tumors with equal or more than 10% nuclear-stained cells were determined to be positive for AR and the relationship between AR and clinicopathological parameters was analyzed.

The expression of HER3 was evaluated by immunohistochemistry using the following scoring system: 0 (no staining), 1 (less than 20% of cells stained or weak staining), 2 (more than or equal to 20% of cells stained, or strong staining) and the relation with AR expression was examined.

The differences among variables were calculated by chi-square test.

Results: The median age of all patients was 56 years old (from 31 to 84). AR-positive carcinomas corresponded to 37(36.2%) of 102 HER2-positive breast carcinomas. The median age of AR-positive patients was 54 years old while that of AR-negative patients was 57 years old. There was no significant difference between the two groups.

AR-positive carcinomas were not associated with ER and progesterone receptor (PgR) co-expression and nuclear grade. The stage distribution of AR-positive patients was: stage I(n = 23), stage IIA(n = 11), stage IIB (n = 3), and averaged 18.5mm in tumor size, while AR-negative patients distributed as stage I(n = 16), stage IIA(n = 27), stage IIB (n = 15), stage IIIA(n = 5), stage IIIB(n = 2), and averaged 23.7mm in size. AR-positive carcinomas were associated with larger pathological tumor size and more advanced clinical stages, though lymph node involvement did not differ between the two groups.

The HER3 expression score distribution was: scrore 0 (n = 14), score 1 (n = 54), score 2 (n = 34). The expression of HER3 was not associated with clinicopathological parameters. Furthermore, there was no significant relation between AR expression and HER3 expression.

Median follow-up interval was 63 months. 20 patients (19.6%) suffered recurrence. Four patients suffered recurrence in the AR-positive group while there were 16 patients in the AR-negative group. AR-positive patients had significant better prognosis in recurrence than AR-negative patients.

Conclusion: Among HER2-positive breast carcinomas, AR-positive carcinomas have the tendency to be smaller in tumor size and of early clinical stage compared with those that are AR-negative. The expression of AR might be a better prognostic factor in HER2-positive breast carcinomas.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-10-04.

Abstract P6-11-11: Characteristics of long-term survivors after brain metastases in breast cancer patients

Background: Brain metastases (BM) occur in 10%-15% patients of breast cancer patients. It is associated with poor prognosis, requiring great effort to manage local and systemic treatment for BM. The purpose of this study was to analyze the clinico-pathological characteristics of long-term survivors with BM in breast cancer patients.

Method: 63 patients with breast cancer BM diagnosed from 2002 to 2010 at the Tokyo Metropolitan Komagome hospital were included. Long–term survival group (Long) was defined as to be consisted of the patients with survival duration more than 36 months after diagnosed with BM and the patients with less than 36 month was into Short-term survival group (Short) in this study. The clinico-pathological characteristics were compared between these two groups. Survival rate and prognostic factors of BM were analyzed by the Kaplan–Meier method and employed by Log–Rank test. Multivariate analysis was performed by the Cox proportional hazard model.

Results: Median age of the 63 patients was 53 years (range, 35–78). Median survival time after BM was 12 months (range, 1–168), with about 90 percent of cause of death related to BM (e.g. failure of PS due to BM). As for ER and HER2 status, the number of ER+/HER2- (Luminal:Lum), ER+or-/HER2+ (HER2-enrich:Her2-E), ER-/HER2- (Basal:Bas) were 18, 27, 18, respectively. Among those 63 patients, 11 survived 36 months or more after BM. However, there was no difference in the rate of ER status between Long (55%) and Short (38%), there were significantly high rate of Her2-E case in Long (73%) as compared with Short (29%). Median survival duration after diagnosed with BM of Lum, Her2-E and Bas were 11, 37, 3 months, respectively. Prognosis of Bas was significantly poor (Bas vs. Her2-E p&lt;0.001), and although Her2-E was not significant as compared with ER (p = 0.188), survival time after BM of Her2-E was the tendency to be long. In univariate analysis, Karnofsky performance status (KPS≥70 or &lt;70), HER2 status, disease free interval (from initial diagnosis to first recurrence, DFI≥2years or &lt;2years) had significant impact on survival time after BM. (p = 0.0458, 0.0398, 0.0385, respectively). Meningitis status was a borderline. (p = 0.052) In multivariate analysis, KPS, HER2 status and DFI were significant prognostic factors. (KPS: RR 2.08, 95% CI 1.08-4.07; HER2: RR 2.911, 95% CI 1.396- 6.484; DFI: RR 1.933, 95% CI 0.83-4.102)

Conclusions: Although, it was believed that the prognosis after BM was poor, Her2-E BM had a comparatively good prognosis. An existing report supports extension of the survival time after BM by HER2–targeted treatment in BM cases with Her2 positive breast cancer. This newest study reviles the median survival after BM as 37 months in Her2-E BM group, but that of Bas group was only 3 months and this is not improved at all compared with historically reported survival duration (2.4-4.9months). Our reports suggested that the innovation of Her2–targeted treatment leads this surprising improvement of life extension in HER2 positive BM patients but innovation of cytotoxic agents could not contribute toward improvement of clinical outcome in triple negative BM patients. So the necessity of examining the medical treatment of breast cancer BM according to subtype from now on is also considered.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-11-11.

Delayed anti-CD3 therapy results in depletion of alloreactive T cells and the dominance of Foxp3+ CD4+ graft infiltrating cells

The engineered Fc-nonbinding (crystallizable fragment-nonbinding) CD3 antibody has lower mitogenicity and a precise therapeutic window for disease remission in patients with type 1 diabetes. Before anti-CD3 can be considered for use in transplantation, the most effective timing of treatment relative to transplantation needs to be elucidated. In this study anti-CD3F(ab')2 fragments or saline were administered intravenously for 5 consecutive days (early: d1-3 or delayed: d3-7) to mice transplanted with a cardiac allograft (H2(b)-to-H2(k); d0). Survival of allografts was prolonged in mice treated with the early protocol (MST = 48 days), but most were rejected by d100. In contrast, in mice treated with the delayed protocol allografts continued to survive long term. The delayed protocol significantly inhibited donor alloreactivity at d30 as compared to the early protocol. A marked increase in Foxp3(+) T cells (50.3 ± 1.6%) infiltrating the allografts in mice treated with the delayed protocol was observed (p < 0.0001 vs. early (24.9 ± 2.1%)) at d10; a finding that was maintained in the accepted cardiac allografts at d100. We conclude that the timing of treatment with anti-CD3 therapy is critical for inducing long-term graft survival. Delaying administration effectively inhibits the alloreactivity and promotes the dominance of intragraft Foxp3(+) T cells allowing long-term graft acceptance.