A method to assess the quality of additive manufacturing metal powders using the triboelectric charging concept

A new method to assess the quality of additive manufacturing (AM) metal powders using the triboelectric charging concept is demonstrated using CpTi, Ti6Al4V, AlSi10Mg, IN 738, and SS 316L powders. For each powder tested, the surface chemical composition was first analyzed using X-ray photoelectron spectroscopy (XPS) to determine the composition of the passivation layer. Some modifications to the current GranuCharge™ setup, developed by GranuTools™, were then performed by incorporating a flow rate measuring tool to assess how tribocharging is affected as a function of flow rate. Variations in the tribocharging response have been found with the flow rate of CpTi, AlSi10Mg and SS 316L powders. Moreover, results suggest that the tribocharging behavior might not be the same even with powders fabricated with the same passivation process. Finally, the compressed exponential model of Trachenko and Zaccone was used to reproduce the tribocharging behavior of the powders. The models were found to work best when the stretch constant β = 1.5, which is identical to the value found in other systems such as structural glasses, colloidal gels, entangled polymers, and supercooled liquids, which experience jamming when motion of individual particles become restricted, causing their motion to slow down.

Very APBI in 1 or 2 Days: Late Toxicity and Early Oncological Outcomes of the GEC-ESTRO Cohort

PURPOSE/OBJECTIVE(S)

To analyze late toxicity after very accelerated partial breast irradiation (VAPBI) for low-risk breast cancer.

MATERIALS/METHODS

In this retrospective observational international multicenter study (HDH F20220713143949) from 7 European centers, patients with low-risk breast cancer underwent lumpectomy + adjuvant VAPBI based on high-dose rate (HDR) multicatheter interstitial brachytherapy (MIB). VAPBI was performed with 4 (4 × 6.2 Gy/2 d), 3 (3 × 7.45 Gy/2 d) or 1 fraction (1 × 16 Gy or 1 × 18 Gy/1 d). Primary endpoint was late toxicity. Secondary endpoints were oncological outcome based on cumulative incidence of breast cancer local relapse (LR) and distant metastasis disease (DMD) and cause-specific (CSS) and overall (OS) survival. Prognostic factors for late toxicity were analyzed.

RESULTS

From 01/2012 to 06/2022, the GEC-ESTRO VAPBI cohort included 516 pts with an early breast cancer. Median follow-up was 42 months [95% CI = 39 - 44]. Median age was 71 years [40 - 100]. Median tumor size was 12 mm [1 - 46]. Tumor was mainly invasive ductal carcinoma (78%), pN0 (88.5%), with positive hormonal receptors (98.5%) and negative HER2 overexpression (96%). Patients underwent hormonal and chemo-therapy in 93.8% and 2.3% respectively. Catheter placement was performed peri or post-operatively in 50.2% and 49.8% respectively. Median time interval between surgery and VABPI was 10 days [6 - 65]. VAPBI delivered 1, 3 and 4 fractions for 205 pts (39.7%), 167 pts (32.4%) and 144 pts (28%) respectively. Median CTV was 40.7 cc [95% CI = 26.6 - 72], median V100%, V150%, D90% and Dose non-uniformity ratio (DNR) were 90.2% [95% CI = 84.1 - 97.2], 24.2% [95% CI = 18.9 - 31.6], 103.8% [95% CI = 100.1 - 107.4] and 0.28 [95% CI = 0.23 - 0.33] respectively, 211 late toxicity events were observed in 168 pts (32.6%). Fibrosis, dyschromia, pain and telangiectasia were observed in 26.7%, 7.9%, 7.2% and 0.4 respectively. Grade 2 and 3 late toxicities were observed in 7.2 and 0.6% respectively (no G4). Grade ≥2 late toxicity was observed in 8.1%, 16.7% and 3.7% after 1, 3 and 4 fractions, respectively (p = 0.004). CTV > 50 cc (p = 0.007) and V150 > 40% (p = 0.027) were prognostic factors for G≥2 late toxicity. Regarding oncological outcome, 4-year cumulative incidence of LR, RR and DMD were 2% [95% CI = 0 - 3], 1% [95% CI = 0 - 2] and 1% [95% CI = 0 - 2] respectively. CSS and OS were 98% [95% CI = 96 - 100] and 93% [95% CI = 90 - 96] respectively. No significant difference was observed in terms of oncological outcome between the 3-fractionation groups.

CONCLUSION

VAPBI based on 1 or 2 days of HDR MIB represents an attractive de-escalation irradiation approach for low-risk breast cancer. Late toxicity profile appears acceptable while early oncological outcome shows excellent local control. Brachytherapy technique remains a key component of clinical outcome. Longer follow-up is warranted in order to confirm these encouraging preliminary results.

Feasible and effective use of a simulation-based curriculum for post-graduate emergency medicine trainees in India to improve learner self-efficacy, knowledge, and skills

BACKGROUND

Pediatric emergency medicine training is in its infancy in India. Simulation provides an educational avenue to equip trainees with the skills to improve pediatric care. We hypothesized that a simulation-based curriculum can improve Indian post-graduate emergency medicine (EM) trainees' self-efficacy, knowledge, and skills in pediatric care.

METHODS

We designed a simulation-based curriculum for management of common pediatric emergencies including sepsis, trauma, and respiratory illness and pediatric-specific procedures including vascular access and airway skills. Training included didactics, procedural skill stations, and simulation. Measures included a self-efficacy survey, knowledge test, skills checklist, and follow-up survey. Results were analyzed using the Wilcoxon signed-rank test and paired-samples t test. A 6-month follow-up survey was done to evaluate lasting effects of the intervention.

RESULTS

Seventy residents from four academic hospitals in India participated. Trainees reported feeling significantly more confident, after training, in performing procedures, and managing pediatric emergencies (p < 0.001). After the simulation-based curriculum, trainees demonstrated an increase in medical knowledge of 19% (p < 0.01) and improvement in procedural skills from baseline to mastery of 18%, 20%, 16%, and 19% for intubation, bag-valve mask ventilation, intravenous access, and intraosseous access respectively (p < 0.01). At 6-month follow-up, self-efficacy in procedural skills and management of pediatric emergencies improved from baseline.

CONCLUSIONS

A simulation-based curriculum is an effective and sustainable way to improve Indian post-graduate EM trainees' self-efficacy, knowledge, and skills in pediatric emergency care.

POS0304 EPIDEMIOLOGY AND ECONOMIC BURDEN ASSOCIATED WITH MENTAL HEALTH COMORBIDITIES IN SYSTEMIC LUPUS ERYTHEMATOSUS AND LUPUS NEPHRITIS PATIENTS

Background:

Systemic lupus erythematosus (SLE), a multisystem autoimmune disease, is associated with mental health (MH) disorders. There is scarce information on the epidemiology and economic burden associated with MH comorbidities and the impact on SLE as well as the subpopulation with lupus nephritis (LN).

Objectives:

Examined the incidence and prevalence rate of MH, healthcare resource utilization (HCRU), and costs associated with MH comorbidities in SLE/LN patients.

Methods:

Adult SLE and LN patients with ≥1 inpatient or ≥2 outpatient diagnosis claims for SLE/LN (ICD-9 code: 710.0; and ICD-10 codes M32.10-19, M32.8, M32.9) were identified between 01JAN2013-30JUN2019 from two large US commercial databases. Inclusion required continuous enrollment benefits 12 months pre-/post-index date. Patients were divided into two groups: those with (WMH) vs. those without (NMH). WMH was defined as a MH diagnosis of depression, anxiety, bipolar disorder, or psychosis. Index date for the WMH group was first MH diagnosis claim. For the NMH group, a random index date was assigned between 01JAN2014-30JUN2018. The groups were then matched with a 1:1 ratio based on age, sex, and region within their respective databases. Incidence and prevalence rate of MH in the SLE/LN population were determined. All-cause healthcare costs and HCRU per patients per year (PPPY) were examined with generalized linear models.

Results:

A total of 7,760 SLE and 336 LN patients were identified. The majority of patients were female (SLE=93.5%; LN=95.2%) with a mean age of 55.1 years (SLE) and 44.5 years (LN). The prevalence rate of MH was 35.7% for SLE and 28.8% for LN patients and the incidence rate was 18.5% and 15.3%, respectively. Anxiety and depression were the most common MH comorbidities (Figure 1). WMH inpatient stays averaged an additional 2.6 and 7.2 days longer than NMH for SLE and LN, respectively. In addition, WMH patients averaged 10.4 (SLE) and 18.4 (LN) significantly more outpatient visits PPPY than NMH. Overall healthcare cost PPPY was significantly higher for WMH patient in both SLE ($49,553 vs $26,064), and LN ($112,169 vs $39,529). Inpatient costs were approximately 3 – 5 times greater in the WMH group (Table 1).

Table 1.

Follow-up Healthcare Cost and Utilization for SLE/LN Case and Control Population

SLE with MH Comorbidities N=3,880 (WMH)SLE without MH comorbidities N=3,880 (NMH)P-valueLN with MH Comorbidities N=168 (WMH)LN without MH comorbidities N=168 (NMH)P-valueAll-cause health care utilization PPPYMeanMeanMeanMeanMean # inpatient visits1.360.50<0.00011.860.86<0.0001Mean # outpatient visits32.1121.67<0.000147.8529.45<0.0001Mean # office visits13.499.74<0.000114.9410.29<0.0001Mean # ER visits1.270.66<0.00011.400.630.0005Mean # other outpatient visits25.5517.08<0.000141.4824.19<0.0001Mean # pharmacy Rx33.3320.82<0.000136.9623.81<0.0001Length of inpatient stay (mean, days)3.691.09<0.00019.532.37<0.0001All-cause health care costs PPPYOutpatient costs (ER+ office +other)$19,271$12,847<0.0001$34,956$19,530<0.0001Pharmacy costs$7,222$4,707<0.0001$7,874$4,254<0.0001Inpatient costs$22,605$8,191<0.0001$68,216$14,680<0.0001Total costs$49,553$26,064<0.0001$112,169$39,529<0.0001

PPPY: Per patient per year; ER: Emergency room; LN: Lupus nephritis; SLE: Systemic lupus erythematosus

Conclusion:

This real-world study shows that MH comorbidities have a high incidence and prevalence rate in SLE and LN patients. Health care costs and utilization for SLE and LN patients with MH comorbidities were significantly higher than patients without MH comorbidities. This study highlights not just the high prevalence of MH comorbidity but its large contribution to SLE healthcare costs.

Figure 1.

Incidence and Prevalence Rate of Mental Health Comorbidities in the SLE and LN Populations LN: Lupus nephritis; SLE: Systemic lupus erythematosus

Disclosure of Interests:

Michelle A Petri Consultant of: Yes, Grant/research support from: Yes, Dominik Naessens Shareholder of: Yes (Johnson and Johnson), Employee of: Employee of Janssen Pharmaceuticals., Adesuwa Ogbomo: None declared, Anna Ratiu: None declared, Cynthia Gutierrez: None declared, Chetan Karyekar Shareholder of: Own Stock Options as part of being a company employee., Employee of: Current employee of Janssen Pharmaceuticals

Enabling Photoactivated Cross-Linking Mass Spectrometric Analysis of Protein Complexes by Novel MS-Cleavable Cross-Linkers

Cross-linking mass spectrometry (XL-MS) is a powerful tool for studying protein-protein interactions and elucidating architectures of protein complexes. While residue-specific XL-MS studies have been very successful, accessibility of interaction regions nontargetable by specific chemistries remain difficult. Photochemistry has shown great potential in capturing those regions because of nonspecific reactivity, but low yields and high complexities of photocross-linked products have hindered their identification, limiting current studies predominantly to single proteins. Here, we describe the development of three novel MS-cleavable heterobifunctional cross-linkers, namely SDASO (Succinimidyl diazirine sulfoxide), to enable fast and accurate identification of photocross-linked peptides by MSⁿ. The MSⁿ-based workflow allowed SDASO XL-MS analysis of the yeast 26S proteasome, demonstrating the feasibility of photocross-linking of large protein complexes for the first time. Comparative analyses have revealed that SDASO cross-linking is robust and captures interactions complementary to residue-specific reagents, providing the foundation for future applications of photocross-linking in complex XL-MS studies.

High parathormone levels are associated with adverse cardiovascular events in coronary patients with high fibroblast growth factor-23

Background

Disturbances of the components of the mineral metabolism (MM) (vitamin D, phosphate, parathormone [PTH], fibroblast growth factor-23 [FGF23] and klotho) have been linked to cardiovascular disease. However, the available data are controversial, probably because most studies deal with individual rather than with the whole MM components.

Purpose

To the study the relationship between MM components and cardiovascular events, after controlling for other well-known markers (N-Terminal pro-brain natriuretic peptide [NT-proBNP], high-sensitivity troponin I [hs-TnI], and high-sensitivity c-reactive protein [hs-CRP]), and relevant clinical variables in stable coronary artery disease (CAD) patients.

Methods

We analyzed the aforementioned markers in 964 CAD patients and followed them subsequently. The primary outcome (PO) was the composite of ischemic events (acute coronary syndrome, stroke or transient ischemic attack), heart failure and death. Secondary outcomes were any ischemic event and the composite of heart failure and death.

Results

Median follow-up was 5.39 years (2.81 - 6.92). Age was 60 (52–72) years and 76.2% patients were male. Median glomerular filtration rate was 80.4 (65.3–93.1) ml/min/1.73 m2. 185 patients developed the PO.

At the univariate analysis PTH, FGF23, NT-proBNP and hs-TnI were directly associated with the PO, while calcidiol and Klotho were inversely related, and phosphate did not reach statistical significance. However, only PTH (HR 1.058 [CI 1.021–1.097]; p=0.002) and NT-proBNP (HR 1.020 [CI 1.012–1.028]; p&lt;0.001) were independent predictors of the PO at multivariate Cox regression analysis. Both PTH and NT-proBNP were also independent predictors of HF or death (HR 1.066 [1.016 - 1.119]; p=0.009 and HR 1.024 [1.014 - 1.034]; p&lt;0.001 respectively), while only PTH predicted ischemic events (HR 1.052 [1.010–1.096]; p=0.016).

After dividing patients in two subgroups according to whether they had FGF23 plasma levels above the median (85.5 RU/ml) or not, PTH remained as a predictor of the PO only in the subgroup with FGF23 &gt;85.5 RU/ml (p&lt;0.001), but not in patients with FGF23 ≤85.5 RU/ml (p=0.551). There was a significant interaction between FGF23 and PTH plasma levels (p=0.002).

Conclusion

PTH predicts cardiovascular events in CAD patients with elevated FGF23 levels even after taking into account all the other components of MM and controlling for NT-ProBNP, hs-CPR and TnI. There is an interaction between PTH and FGF23 levels, and they should be assessed together when exploring their potential predictive power.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Fondo de Investigaciones Sanitarias

OP0035 EXAMINATION OF INTERSTITIAL LUNG DISEASE IN PATIENTS WITH RHEUMATOID ARTHRITIS – PREVALENCE, TIME TO ONSET, AND CLINICAL CHARACTERISTICS

Background:

Interstitial lung disease (ILD) is a known extraarticular manifestation of rheumatoid arthritis (RA). Previous studies have shown variability in the prevalence of RA-ILD, as well as clinical characteristics and risk factors of RA-ILD.

Objectives:

To evaluate the prevalence and time to onset of ILD and compare the clinical characteristics between RA patients (pts) with or without ILD using a large US electronic medical record (EMR)-based dataset.

Methods:

Pts with an initial RA diagnosis (ICD-9-CM code: 714.0; ICD-10-CM codes: M05 & M06) during the study period (01JAN2009-20SEP2019) were included from the Discus Analytics JointMan database. The initial RA diagnosis date was defined as the index date. Pts with ILD were identified by ICD diagnosis codes or by provider indication in the JointMan record. Pts who developed ILD before RA were excluded from this analysis. The prevalence and time to onset of ILD were reported. Pt demographics, comorbidities, RA characteristics and disease activity scores were compared for 6 months prior to or on the index date (baseline period) for selected adult RA pts with available information.

Results:

Among 8,963 identified RA pts, 337 (3.8%) were diagnosed with ILD on or after RA diagnosis. The median time to ILD onset post-RA was 2.3 years, and 47% had ILD within 2 years after RA diagnosis. RA-ILD pts were significantly older than those without ILD (65.8 years vs. 59.1 years; p<0.001; Table 1). At baseline, a higher percentage of RA-ILD pts had history of chronic obstructive pulmonary disease, positive rheumatoid factor, rheumatoid nodules, erosive joint disease, positive anti-cyclic citrullinated peptide antibody, and joint swelling compared to RA-only pts (Table 2). The mean ESR and RA disease activity scores were also significantly higher for RA-ILD pts.

Table 1.

Patient Demographics

Patient demographicsRA-ONLY COhort(N = 5,612)RA-ild coHORT(N = 205)P-valueAge, Mean ± SD, years59.1 ± 14.265.8 ± 11.8<.001Male, N (%)1,375 (24.5%)72 (35.1%)0.001Race, N (%) White4,014 (71.5%)165 (80.5%)0.005 African American365 (6.5%)9 (4.4%)0.226 Other/Missing1,233 (22.0%)31 (15.1%)0.020Table 2.

Baseline Clinical Characteristics

Clinical CharacteristicsRA-ONLY COhort(N = 3,846)RA-ild coHORT(N = 115)P-valueHistory of Chronic Obstructive Pulmonary Disease, N (%)102 (2.7%)8 (7.0%)0.006Hypertension, N (%)900 (23.4%)23 (20.0%)0.395Serious Infection, N (%)38 (1.0%)3 (2.6%)0.091Rheumatoid Factor Positive, N (%)1,388 (36.1%)69 (60.0%)<.001Joint Stiffness, N (%)1,092 (28.4%)39 (33.9%)0.197Rheumatoid Nodules, N (%)153 (4.0%)17 (14.8%)<.001Erosive Joint Disease, N (%)459 (11.9%)23 (20.0%)0.009Anti-CCP Antibody Positive, N (%)858 (22.3%)45 (39.1%)<.001Joint Swelling*, N (%)2,861 (58.0%)123 (68.0%)0.008Joint Tenderness*, N (%)3,728 (75.6%)138 (76.2%)0.851ESR**, Mean ± SD, mm/hr22.0 ± 22.630.1 ± 25.5<.001CRP**, Mean ± SD, mg/L22.5 ± 13.060.6 ± 25.00.086CDAI, Mean ± SD16.4 ± 12.318.9 ± 15.70.044DAS28-CRP, Mean ± SD2.6 ± 1.23.1 ± 1.4<.001DAS28-ESR, Mean ± SD3.3 ± 1.43.9 ± 1.5<.001SDAI, Mean ± SD20.2 ± 29.328.6 ± 40.20.048

* A total of 4,929 non-ILD and 181 ILD patients had joint swelling and tenderness data.

** Variables were calculated among patients who had available information.

Conclusion:

This large real-world RA population provides insight into the burden of ILD in RA pts. Pts with ILD had a higher proportion of comorbidities and RA-related conditions and higher RA activity. Further analysis is warranted to assess the risk factors of ILD and its prognosis.

Disclosure of Interests:

Joe Zhuo Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Qisu Zhang Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Keith Knapp Consultant of: In the last year, I was a paid consultant to Bristol Myers-Squibb Company., Employee of: I am a paid employee of Discus Analytics., Yuexi Wang Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Cynthia Gutierrez Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Ding He Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Lin Xie Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Sonie Lama Shareholder of: I own shares of Bristol-Myers Squibb Company., Employee of: I am a paid employee of Bristol-Myers Squibb Company., Gary Craig Consultant of: I have served as a consultant to Bristol-Myers Squibb Company., Employee of: I am a paid employee of Arthritis Northwest and VP of Discus Analytics., Speakers bureau: I am a member of the speakers bureau for Bristol-Myers Squibb Company.

SAT0616-HPR IMPLICATED FACTORS IN THERAPEUTIC ADHERENCE OF PATIENTS WITH RHEUMATOID ARTHRITIS: THE PATIENT´S PERSPECTIVE

Background:

Therapeutic adherence has become a topic of growing interest for medical research. Studies have reported non-adherence rates of 20-50% in rheumatoid arthritis (RA) patients (1). Poor adherence has a negative impact on disease outcomes and implies an economic burden for the health system (2). Identifying the potential risk factors for non-adherence is essential to develop intervention strategies to solve this problem

Objectives:

To establish the contribution of illness and medication beliefs to therapeutic adherence in RA. To explore the association of treatment adherence with other patient and disease factors.

Methods:

RA patients ≥ 18 years old from a military hospital diagnosed with RA based on ACR /EULAR 2010 criteria were included in a cross-sectional study. Compliance Questionnaire Rheumatology (CQR) was used to assess treatment adherence. Unsatisfactory compliance was defined as taking correct dosing < 80%. Illness and medication beliefs were evaluated using the “Brief Illness Perception Questionnaire “(IPQ-b) and the “Beliefs about medicine questionnaire” (BMQ). Demographic data and clinical characteristics were collected by standardized clinical interview and revision of medical records.

Results:

144 patients were included the study, 106 (73.6%) women, with a mean age of 62 years (SD 12) and median disease duration of 5 years (interquartile range 25-75: 2-11). 113 (78.4%) patients showed good treatment adherence. No differences were observed regarding demographics and clinical characteristics. Strong beliefs about drugs potential damage was associated with poor compliance (13±5 vs. 11±3, p= 0.013), meanwhile increased belief in medication necessity was associated with good compliance (21±3 vs. 20±3, p= 0.015). From the illness perception measures, adherent patients had increased feeling of treatment control (8.8± 1.5 vs 7.7± 2.1,p= 0.008) and greater emotional response (6.2±3.1 vs 4.8±3.4,p= 0.042). In a multivariate analysis was found that for each unit of increase in the score of BMQ´s damage domain, adherence was reduced by 20% (CI 95% 0.7-0.9, p= 0.001); for each unit of increase in the treatment control item of the IPQ-b, adherence increased 1.42 times (CI 95% 1.1-1.8,p= 0.006); and for each unit of increase in the emotional response item of the IPQ-b, adherence increased 1.2 times (CI 95% 1.08-1.46,p= 0.002).

Conclusion:

Illness and medication beliefs could influence compliance to treatment in patients with RA.

References:

[1]van den Bemt BJ, van den Hoogen FH, Benraad B, et al. Adherence rates and association with nonadherence in patients with rheumatoid arthritis using disease modifyin antirheumatic drugs. J Rheumatol. 2009;36(10):2164–70.

[2]Martikainen JA, Kautiainen H, Rantalaiho V, et al.. Longterm Work Productivity Costs Due to Absenteeism and Permanent Work Disability in Patients with Early Rheumatoid Arthritis : A Nationwide Register Study of 7831 Patients. J Rheumatol. 2016;43(12):2101–5.

Disclosure of Interests:

María Ahijón: None declared, Patricia Carreira Grant/research support from: Actelion, Roche, MSD, Consultant of: GlaxoSmithKline, VivaCell Biotechnology, Emerald Health Pharmaceuticals, Boehringer Ingelheim, Roche, Speakers bureau: Actelion, GlaxoSmithKline, Roche, Carmen De La Cruz: None declared, Raúl Veiga: None declared, Carlos Gutierrez: None declared

First Community-Wide, Comparative Cross-Linking Mass Spectrometry Study

The number of publications in the field of chemical cross-linking combined with mass spectrometry (XL-MS) to derive constraints for protein three-dimensional structure modeling and to probe protein-protein interactions has increased during the last years. As the technique is now becoming routine for in vitro and in vivo applications in proteomics and structural biology there is a pressing need to define protocols as well as data analysis and reporting formats. Such consensus formats should become accepted in the field and be shown to lead to reproducible results. This first, community-based harmonization study on XL-MS is based on the results of 32 groups participating worldwide. The aim of this paper is to summarize the status quo of XL-MS and to compare and evaluate existing cross-linking strategies. Our study therefore builds the framework for establishing best practice guidelines to conduct cross-linking experiments, perform data analysis, and define reporting formats with the ultimate goal of assisting scientists to generate accurate and reproducible XL-MS results.

A combinatorial biomarker predicts pathologic complete response to neoadjuvant lapatinib and trastuzumab without chemotherapy in patients with HER2+ breast cancer

BACKGROUND

HER2-positive (+) breast cancers, defined by HER2 overexpression and/or amplification, are often addicted to HER2 to maintain their malignant phenotype. Yet, some HER2+ tumors do not benefit from anti-HER2 therapy. We hypothesize that HER2 amplification levels and PI3K pathway activation are key determinants of response to HER2-targeted treatments without chemotherapy.

PATIENTS AND METHODS

Baseline HER2+ tumors from patients treated with neoadjuvant lapatinib plus trastuzumab [with endocrine therapy for estrogen receptor (ER)+ tumors] in TBCRC006 (NCT00548184) were evaluated in a central laboratory for HER2 amplification by fluorescence in situ hybridization (FISH) (n = 56). HER2 copy number (CN) and FISH ratios, and PI3K pathway status, defined by PIK3CA mutations or PTEN levels by immunohistochemistry were available for 41 tumors. Results were correlated with pathologic complete response (pCR; no residual invasive tumor in breast).

RESULTS

Thirteen of the 56 patients (23%) achieved pCR. None of the 11 patients with HER2 ratio <4 and/or CN <10 achieved pCR, whereas 13/45 patients (29%) with HER2 ratio ≥4 and/or CN ≥10 attained pCR (P = 0.0513). Of the 18 patients with tumors expressing high PTEN or wild-type (WT) PIK3CA (intact PI3K pathway), 7 (39%) achieved pCR, compared with 1/23 (4%) with PI3K pathway alterations (P = 0.0133). Seven of the 16 patients (44%) with HER2 ratio ≥4 and intact PI3K pathway achieved pCR, whereas only 1/25 (4%) patients not meeting these criteria achieved pCR (P = 0.0031).

CONCLUSIONS

Our findings suggest that there is a clinical subtype in breast cancer with high HER2 amplification and intact PI3K pathway that is especially sensitive to HER2-targeted therapies without chemotherapy. A combination of HER2 FISH ratio and PI3K pathway status warrants validation to identify patients who may be treated with HER2-targeted therapy without chemotherapy.

In vivo assembly and trafficking of olfactory Ionotropic Receptors

Background

Ionotropic receptors (IRs) are a large, divergent subfamily of ionotropic glutamate receptors (iGluRs) that are expressed in diverse peripheral sensory neurons and function in olfaction, taste, hygrosensation and thermosensation. Analogous to the cell biological properties of their synaptic iGluR ancestors, IRs are thought to form heteromeric complexes that localise to the ciliated dendrites of sensory neurons. IR complexes are composed of selectively expressed ‘tuning’ receptors and one of two broadly expressed co-receptors (IR8a or IR25a). While the extracellular ligand-binding domain (LBD) of tuning IRs is likely to define the stimulus specificity of the complex, the role of this domain in co-receptors is unclear.

Results

We identify a sequence in the co-receptor LBD, the ‘co-receptor extra loop’ (CREL), which is conserved across IR8a and IR25a orthologues but not present in either tuning IRs or iGluRs. The CREL contains a single predicted N-glycosylation site, which we show bears a sugar modification in recombinantly expressed IR8a. Using the Drosophila olfactory system as an in vivo model, we find that a transgenically encoded IR8a mutant in which the CREL cannot be N-glycosylated is impaired in localisation to cilia in some, though not all, populations of sensory neurons expressing different tuning IRs. This defect can be complemented by the presence of endogenous wild-type IR8a, indicating that IR complexes contain at least two IR8a subunits and that this post-translational modification is dispensable for protein folding or complex assembly. Analysis of the subcellular distribution of the mutant protein suggests that its absence from sensory cilia is due to a failure in exit from the endoplasmic reticulum. Protein modelling and in vivo analysis of tuning IR and co-receptor subunit interactions by a fluorescent protein fragment complementation assay reveal that the CREL N-glycosylation site is likely to be located on the external face of a heterotetrameric IR complex.

Conclusions

Our data reveal an important role for the IR co-receptor LBD in control of intracellular transport, provide novel insights into the stoichiometry and assembly of IR complexes and uncover an unexpected heterogeneity in the trafficking regulation of this sensory receptor family.

Electronic supplementary material

The online version of this article (10.1186/s12915-019-0651-7) contains supplementary material, which is available to authorized users.

Abstract P2-07-06: Cumulative copy number imbalances after neoadjuvant chemotherapy residual breast tumor is an independent predictor of relapse

Background: Identifying breast cancer patients after neoadjuvant chemotherapy (NAC) at greatest risk of recurrence would enhance selection of patients who may benefit from novel adjuvant treatments.

Patients. 243 stage I-III breast cancer patients who underwent NAC with ≥10% residual tumor cellularity were identified from the MD Anderson Cancer Center and Ben Taub General Hospital, Harris County hospital. Tumor DNA was isolated for DNA copy number using OncoScan CNV FFPE, Affymetrix. Median follow-up was 67.8 months. Continuous residual cancer burden (RCB) scores with CNI data were available for 152 cases. To test if CNIs covering large regions were associated with recurrence after adjusting for prognostic variables and study site, data were summed to a chromosome-arm level. Eleven chromosome arms with false discovery rate &lt;0.05 for breast cancer recurrence were identified. A stepwise multivariable model including age at diagnosis, tumor subtype, histologic grade, pre- and post-treatment stage, study site, and the 11 chromosomal arms were used to fit a parsimonious multivariate model for recurrence. Minimizing the Akaike Information Criterion yielded a final model with post-stage and a 5-arm CNI (5A-CNI) indicator including 2q, 3q, 4q, 10p, and 18p. Tumors were classified on 5A-CNI as 0 [no CNI], 1 [1- 2] and 2 [&gt; 2].

Results. The study population included 76 non-Hispanic White, 89 Hispanic, and 68 African American patients with a mean age of 49.1 years. 105 patients were classified as 5A-CNI-0, 97 as 5A-CNI-1 and 41 as 5A-CNI-2. A higher 5A-CNI score was associated with tumor grade, ER-negative tumors (p&lt;0.002) and tumor subtype (p=0.014). For 5A-CNI scores of 0, 1 and 2, recurrence rates of 14%, 34% and 58.5% were observed, respectively. In the final multivariable model adjusted for post-stage, RCB and study site, when compared to 5A-CNI-0, the hazard of recurrence was elevated for 5A-CNI-1 (HR= 2.27 [95% CI, 1.01-5.1]) and 5A-CNI-2 tumors (HR=7.43 [95% CI, 2.85-19.39]). Further, while the sample size is limiting, of 10 patients who were RCB3 and 5A-CNI-2, 9 relapsed (90%) during follow-up compared to only 6 of 43 (14%) of RCB3 patients with 5A-CNI-0 (p&lt;10-6). For patients with RCB1 or 2, relapse did not differ by 5A-CNI score. Neither race nor ethnicity were found to be independently associated with recurrence or tumor subtype. However, African American, followed by Hispanic patients, were more likely than non-Hispanic White patients to be classified as 5A-CNI-2 (p=0.013).

Table 1.Significant difference in distribution of 5 arm CNI classifier by Race/Ethnicity in Study Sample (p =0.013).5A-CNI012Non-Hispanic Whiten=44; 57.9%n=25; 32.9%n=7; 9.2%Hispanicn=32; 36%n=42; 47.2%n=15; 16.9%African Americann=28; 41.2%n=23; 33.8%n=17; 25%

Conclusion. The 5A-CNI score in post NAC tumor identifies a patient population with very poor prognosis independent of current clinical prognostic factors including RCB. Validation of these findings may lead to a post NAC genomic test that identifies patients who would benefit from additional treatment Further investigation of the nature of the association between the 5A-CNI score and race/ethnicity, which appears independent of tumor subtype, is warranted.

Citation Format: Thompson PA, Brewster A, Tsavachidis S, Armstrong G, Do K-A, Ha M-J, Gutierrez C, Symmans F, Bondy M. Cumulative copy number imbalances after neoadjuvant chemotherapy residual breast tumor is an independent predictor of relapse [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 P2-07-06.

Abstract P4-15-05: Biomarkers of response to neoadjuvant endocrine therapy with anastrozole (Ana) alone or in combination with fulvestrant (Ful) in ER-positive (ER+) HER2-negative (HER2-) breast cancer (PACT01 trial)

Background: In recent years, several clinical trials showed that fulvestrant (Ful), alone or in combination with an aromatase inhibitor (AI), is more effective than an AI alone. PACT01 is a randomized neoadjuvant trial of Anastrazole (Ana) alone or in combination with Ful in ER+/HER2- breast cancer.

Methods: Patients with newly diagnosed ER+/HER2- breast cancers, 2 cm or larger in size, were randomized to 16 weeks of Ana (1 mg orally every day) alone or in combination with Ful (500mg IM days 1, 15, 29, and every 28 days thereafter) for 16 weeks. Patients then proceeded to surgery. Tumor tissue was collected at baseline, day 28 (D28), and at the time of surgery. Primary endpoint was the reduction of Ki67 in tumor tissue between baseline and D28. Baseline and D28 samples were stained for ER, PR, HER2, and Ki67. ER and PR were scored for intensity and percentage (H-score), HER2 was scored for intensity of membrane staining; and Ki67 was scored as percentage. Data were summarized descriptively. Changes in biomarkers from baseline to D28 were calculated and compared by Wilcoxon signed rank test.

Results: PACT01 trial enrolled 72 patients. Three of them did not start treatment. Baseline samples were collected from the remaining 69 patients, and D28 samples from 60 patients (5 refused, 2 withdrew, 1 lost to follow up, 1 unknown). Samples from 18 patients had no tumor (5 at baseline, 9 at D28, 4 at both). Of the 42 patients with paired samples, 20 received Ana and 22 received Ana+Ful. All cases except one were centrally confirmed to be ER+, and all were HER2-. Table 1 summarizes median expression of Ki67, ER, and PR. Both treatment regimens led to a significant reduction in Ki67 between baseline and D28. However, Ana+Ful did not reduce Ki67 more effectively than Ana alone. Ki67 was reduced to &lt;10% in 60% of the Ana arm and 68% of the Ana+Ful, which was not statistically significant.PR was similarly reduced in both treatment arms. ER was significantly reduced at D28 in the Ana+Ful arm (p=0.0004) but not in the Ana alone arm. Safety profile of both treatment arms was consistent with package insert and published studies.

Median expression of Ki67, ER and PR in Anastrazole and Anastrazole + Fulvestrant Arms at Baseline and Day 28ARMTimepointNKi67 (%)ER H-scorePR H-scoreAnaBaseline2024.8182.5100.3 Day 28205.6*170.025.0Ana + FluBaseline2225.6198.120.5 Day 28225.1*117.50.0* p=0.0004. Other comparisons were not stastistically significant

Conclusions:In this small neoadjuvant trial, the addition of Ful to Ana did not increase Ki67 suppression at D28. This may be due to untreated primary tumors being exquisitely sensitive to Ana and that fulvestrant may not add to it. It is also possible that the effect of Ful may be noted later in the course of treatment. Further biomarker data on tissue collected at the end of treatment will be presented at the meeting.

Citation Format: Dhamne S, Nagi C, Wang T, Pavlick AC, Reusser B, Schiff R, Julie N, Niravath P, Silberfein EJ, Sedgwick EL, Sepulveda KA, Gutierrez C, Hilsenbeck SG, Chang JC, Osborne CK, Rimawi MF. Biomarkers of response to neoadjuvant endocrine therapy with anastrozole (Ana) alone or in combination with fulvestrant (Ful) in ER-positive (ER+) HER2-negative (HER2-) breast cancer (PACT01 trial) [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 P4-15-05.

Development and content validation of measures assessing adherence barriers and behaviors for use in clinical care

BACKGROUND

Providers are often unaware of poor adherence to prescribed medications for their patients with chronic diseases.

OBJECTIVE

To develop brief, computer-administered patient-reported measures in English and Spanish assessing adherence behaviors and barriers. Design, Participants, and Main Measures: Item pools were constructed from existing measures of medication adherence behaviors and barriers, which informed development of a patient concept elicitation interview guide to identify medication adherence behavior and barrier-related concepts. Two hundred six patients either living with HIV (PLWH) or without were interviewed. Interviews were coded, concepts matched to item pool content, and new items were developed for novel concepts. A provider/investigator team highlighted clinically relevant items. Cognitive interviews were conducted with patients on final candidate items (n = 37). The instruments were administered to 2081 PLWH.

KEY RESULTS

Behavioral themes from concept elicitation interviews included routines incorporating time of day, placement, visual cues, and intentionality to miss or skip doses. Barrier themes included health-related (e.g. depressed mood, feeling ill), attitudes/beliefs (e.g., need for medication), access (e.g., cost/insurance problems), and circumstantial barriers (e.g., lack of privacy, disruption of daily routine). The final instruments included 6 behavior items, and 1 barrier item with up to 23 response options. PLWH endorsed a mean (SD) of 3.5 (1.1) behaviors. The 201 PLWH who missed ≥2 doses in the previous week endorsed a mean (SD) of 3.1 (2.5) barriers. The intraclass correlation coefficient (ICC) for the numbers of behaviors endorsed in 61 PLWH after 4-16 days was 0.54 and for the number of barriers for the 20 PLWH with ≥2 missed doses the ICC was 0.89, representing fair and excellent test-retest reliability.

CONCLUSION

Measures of medication adherence behaviors and barriers were developed for use with patients living with chronic diseases focusing on clinical relevance, brevity, and content validity for use in clinical care.

[Epidemiology of Q fever in Spain (2018)]

Q fever is an anthropozoonosis whose causative agent is Coxiella burnetii, which has an important impact from the human and animal health point of view. In this review, a brief historical reference of the infection by C. burnetii and Q fever has been made initially. In a second section the basic epidemiological aspects of this infection are described (reservoirs/ sources of infection, form of transmission and epidemiological forms). Subsequently, the data of the infection by C. burnetii in Spain will be are indicated, particularly the clinical series, the seroepidemiological studies in humans, the affectation of different types of mammals and the participation of the ticks in the biological cycle. In addition, basic data on C. burnetii infection/ disease in other regions of the world will be are also included. Finally, and taking into account the previous data will indicate the main epidemiological characteristics of Q fever at present.

Abstract P2-03-01: Analytical validation of a standardized scoring protocol for Ki67 assessed on breast excision whole sections: An international multicenter collaboration

Aims: (i) Determine whether between-observer reproducibility for Ki67 when assessed on whole sections according to a standardized scoring protocol is adequate for clinical application. (ii) Compare between-observer reproducibility of Ki67 scores assessed on hot-spots to scores using a global method that averages across a tissue section.

Background: The nuclear proliferation biomarker Ki67 has multiple potential roles in breast cancer, including aiding decisions based on prognosis, but unacceptable levels of between-laboratory variability have been observed. The International Ki67 in Breast Cancer Working Group has undertaken a systematic program to determine whether Ki67 measurement can be analytically validated and standardized across labs. In phase 1, variability in visual interpretation was identified as an important source of variability. Phases 2 and 3a showed that adherence to defined scoring methods substantially improved reproducibility in scoring tissue microarrays and core-cut biopsies. We now assess whether acceptable reproducibility can be achieved on whole sections.

Methods: Adjacent sections from 30 primary ER+ breast cancers were centrally stained for Ki67 to assemble 4 sets of 30 stained tumor sections, circulated around 23 labs in 12 countries. Ki67 was scored by 2 methods by all labs: (a) global: 4 fields of 100 tumor cells each were selected to reflect observed heterogeneity in nuclear staining (b) hot-spot: the field with highest Ki67 percentage of tumor cells with nuclear staining was selected and up to 500 cells scored. Ki67 scores were log2-transformed for statistical analyses and back-transformed for presentation. The primary objective was to assess whether either method could achieve an intraclass correlation coefficient (ICC) significantly greater than 0.8, considered substantial to almost-perfect reproducibility. Secondary objectives were to assess which method had highest observed ICC and to assess whether observers identified the same “hot-spots”.

Results: ICC for the global method was 0.87 (95%CI: 0.799-0.93), marginally meeting the prespecified success criterion. The ICC for the hot-spot method was 0.83 (95%CI: 0.74-0.90) and had a CI extending below the success criterion. Across the 23 labs, geometric mean value of the 30 scores ranged from 8.5 to 19.6 for the global method and from 12.8 to 30.3 for the hot-spot method. The overall mean (95% CI) of these values was 12.9 (11.9-14.0) and 20.9 (19.1-22.8), respectively. Visually, between-laboratory agreement in location of selected hot-spot varies between cases. The median times for scoring were 9 and 6 minutes for global and hot-spot methods respectively.

Conclusions: The global method marginally met the prespecified criterion of success; it should now be evaluated for clinical validity in appropriate cohorts of cases. The hot-spot method was observed to have slightly less reproducibility between labs. The time taken for scoring by either method is practical using counting software we are making publicly available. Establishment of external quality assessment schemes is likely to improve the reproducibility between labs further.

(Supported by a grant from the Breast Cancer Research Foundation)

Citation Format: Nielsen TO, Leung SCY, Zabaglo LA, Arun I, Badve SS, Bane AL, Bartlet JMS, Borgquist S, Chang MC, Dodson A, Ehinger A, Fineberg S, Focke CM, Gao D, Gown AM, Gutierrez C, Hugh JC, Kos Z, Lænkholm A-V, Mastropasqua MG, Moriya T, Nofech-Mozes S, Osborne CK, Penault-Llorca FM, Piper T, Sakatani T, Salgado R, Starczynski J, Sugie T, van der Vegt B, Viale G, Hayes DF, McShane LM, Dowsett M. Analytical validation of a standardized scoring protocol for Ki67 assessed on breast excision whole sections: An international multicenter collaboration [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 P2-03-01.