Leigh syndrome: an adult presentation of a paediatric disease

A previously healthy 27-year-old man was admitted to the acute neurology ward with events involving his face, throat and upper limb, which video telemetry later confirmed were refractory focal seizures. He also had progressive pyramidal features, dysarthria and ataxia. MR scans of the brain identified progressive bilateral basal ganglia abnormalities, consistent with Leigh syndrome. However, extensive laboratory and genetic panels did not give a unifying diagnosis. A skeletal muscle biopsy showed no histopathological abnormalities on routine stains. Sequencing of the entire mitochondrial genome in skeletal muscle identified a well-characterised pathogenic variant (m.10191T>C in MT-ND3; NC_012920.1) at 85% heteroplasmy in skeletal muscle. We discuss the clinical and molecular diagnosis of an adult presenting with Leigh syndrome, which is more commonly a paediatric presentation of mitochondrial disease, and how early recognition of a mitochondrial cause is important to support patient care.

Texas Hospitals' Perspectives About NICU Performance Measures: A Mixed-Methods Study

BACKGROUND AND OBJECTIVES

This study was conducted to assess Texas hospital leaders' perspectives about neonatal intensive care (NICU) performance measures.

METHODS

We conducted an explanatory mixed-methods study. First, we sent a survey and a copy of the Dartmouth Atlas of Neonatal Intensive Care to clinical and administrative leaders of 150 NICUs in Texas. We asked respondents to review the chapter that reported Texas-specific results and respond to a variety of open and closed-ended questions about the overall usefulness of the report. Second, we conducted semistructured qualitative interviews with a subset of survey respondents to better understand their perspectives.

RESULTS

The survey had a 50% hospital response rate. Respondents generally found the report to be interesting and useful, and 87.7% of all respondents reported being in favor of receiving future reports with their own hospital's data benchmarked against anonymous peers. All of the specific measures in the Atlas were found to be of interest and valuable, with NICU admissions and special care days rating among the most interesting and useful. In the semistructured interviews, respondents expressed that a report with performance data would serve as a mechanism to drive change by identifying opportunities for improvement.

CONCLUSION

Texas hospital NICU leaders are interested in routinely receiving more information about their own NICU's performance anonymously benchmarked against their peers. This would facilitate a greater understanding of a unit's functionality, as well as accelerate clinically appropriate quality improvement initiatives, which together have the potential to deliver better newborn care at lower costs for all Texans.

Use of a Novel Network-Based Linchpin Score to Characterize Accessibility to the Oncology Physician Workforce in the United States

Importance

Physician headcounts provide useful information about the cancer care delivery workforce; however, efforts to track the oncology workforce would benefit from new measures that capture how essential a physician is for meeting the multidisciplinary cancer care needs of the region. Physicians are considered linchpins when fewer of their peers are connected to other physicians of the same specialty as the focal physician. Because they are locally unique for their specialty, these physicians' networks may be particularly vulnerable to their removal from the network (eg, through relocation or retirement).

Objective

To examine a novel network-based physician linchpin score within nationwide cancer patient-sharing networks and explore variation in network vulnerability across hospital referral regions (HRRs).

Design, Setting, and Participants

This cross-sectional study analyzed fee-for-service Medicare claims and included Medicare beneficiaries with an incident diagnosis of breast, colorectal, or lung cancer from 2016 to 2018 and their treating physicians. Data were analyzed from March 2022 to October 2022.

Exposures

Physician characteristics assessed were specialty, rurality, and Census region. HRR variables assessed include sociodemographic and socioeconomic characteristics and use of cancer services.

Main Outcomes and Measures

Oncologist linchpin score, which examined the extent to which a physician's peers were connected to other physicians of the same specialty as the focal physician. Network vulnerability, which distinguished HRRs with more linchpin oncologists than expected based on oncologist density. χ2 and Fisher exact tests were used to examine relationships between oncologist characteristics and linchpin score. Spearman rank correlation coefficient (ρ) was used to measure the strength and direction of relationships between HRR network vulnerability, oncologist density, population sociodemographic and socioeconomic characteristics, and cancer service use.

Results

The study cohort comprised 308 714 patients with breast, colorectal, or lung cancer. The study cohort of 308 714 patients included 161 206 (52.2%) patients with breast cancer, 76 604 (24.8%) patients with colorectal cancer, and 70 904 (23.0%) patients with lung cancer. In our sample, 272 425 patients (88%) were White, and 238 603 patients (77%) lived in metropolitan areas. The cancer patient-sharing network included 7221 medical oncologists and 3573 radiation oncologists. HRRs with more vulnerable networks for medical oncology had a higher percentage of beneficiaries eligible for Medicaid (ρ, 0.19; 95% CI, 0.08 to 0.29). HRRs with more vulnerable networks for radiation oncology had a higher percentage of beneficiaries living in poverty (ρ, 0.17; 95% CI, 0.06 to 0.27), and a higher percentage of beneficiaries eligible for Medicaid (ρ, 0.21; 95% CI, 0.09 to 0.31), and lower rates of cohort patients receiving radiation therapy (ρ, -0.18; 95% CI, -0.28 to -0.06; P = .003). The was no association between network vulnerability for medical oncology and percent of cohort patients receiving chemotherapy (ρ, -0.03; 95% CI, -0.15 to 0.08).

Conclusions and Relevance

This study found that patient-sharing network vulnerability was associated with poverty and lower rates of radiation therapy. Health policy strategies for addressing network vulnerability may improve access to interdisciplinary care and reduce treatment disparities.

Conflicts of interest in electrophysiology and devices presentations

AIMS

Industry collaboration with arrhythmia and devices research is common. However, this results in conflicts of interest (CoI) for researchers that should be disclosed. This study aimed to examine the quality of CoI disclosures in arrhythmia and devices presentations.

METHODS

Recorded presentations from the Arrhythmia & Devices section of the ESC Annual Congress 2016-2020 were assessed. The number of words, conflicts, and time displayed was documented for CoI declarations. Meta-data including sponsorship by an industry partner, presenter sex, and institution were obtained.

RESULTS

Of 1153 presentations assessed, 999 were suitable for inclusion. CoI statements were missing from 7.2% of presentations, and 58% reported ≥1 conflict. Those with conflicts spent less time-per-word on their disclosures (median 150 ms, interquartile range [IQR] 83-273 ms) compared with those without conflicts (median 250 ms, IQR 125-375 ms). One-in-eight presentations were sponsored (12.8%, n = 128). CoI statements were more likely to be missing in sponsored presentations (14.8%, n = 19) compared with non-sponsored presentations (6.1%, n = 53), P = 0.0003. Sponsored presentations contained a greater median number of CoIs (10, IQR 6-18) compared with non-sponsored sessions (1, IQR 0-5), P < 0.0001. Time-per-word spent on COI disclosures was 50% lower in sponsored sessions (125 ms, IQR 75-231 ms) compared with non-sponsored sessions (250 ms, IQR 125-375 ms), P < 0.0001.

CONCLUSION

The majority of those presenting arrhythmia and devices research have CoIs to declare. Declarations were often missing or displayed for short periods of time. Presenters in sponsored sessions, while being more conflicted, had a lower standard of declaration suggesting a higher risk of potential bias which viewers had insufficient opportunity to assess.

Rural-Urban Differences in Breast Cancer Surgical Delays in Medicare Beneficiaries

BACKGROUND

Delays between breast cancer diagnosis and surgery are associated with worsened survival. Delays are more common in urban-residing patients, although factors specific to surgical delays among rural and urban patients are not well understood.

METHODS

We used a 100% sample of fee-for-service Medicare claims during 2007-2014 to identify 238,491 women diagnosed with early-stage breast cancer undergoing initial surgery and assessed whether they experienced biopsy-to-surgery intervals > 90 days. We employed multilevel regression to identify associations between delays and patient, regional, and surgeon characteristics, both in combined analyses and stratified by rurality of patient residence.

RESULTS

Delays were more prevalent among urban patients (2.5%) than rural patients (1.9%). Rural patients with medium- or high-volume surgeons had lower odds of delay than patients with low-volume surgeons (odds ratio [OR] = 0.71, 95% confidence interval [CI] = 0.58-0.88; OR = 0.74, 95% CI = 0.61-0.90). Rural patients whose surgeon operated at ≥ 3 hospitals were more likely to experience delays (OR = 1.29, 95% CI = 1.01-1.64, Ref: 1 hospital). Patient driving times ≥ 1 h were associated with delays among urban patients only. Age, black race, Hispanic ethnicity, multimorbidity, and academic/specialty hospital status were associated with delays.

CONCLUSIONS

Sociodemographic, geographic, surgeon, and facility factors have distinct associations with > 90-day delays to initial breast cancer surgery. Interventions to improve timeliness of breast cancer surgery may have disparate impacts on vulnerable populations by rural-urban status.

GPCR-dependent pathways promote nanodomain-specific cAMP signaling in human cardiomyocytes, which is severely remodeled in atrial fibrillation

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Deutsche Forschungsgemeinschaft, German Centre for Cardiovascular Research (DZHK)

Background

Cardiac arrhythmias, such as atrial fibrillation (AF), have been linked to the remodeling of membrane receptors and alterations in cAMP-dependent regulation of calcium handling mechanisms. For instance, decreased L-type calcium channel (LTCC) current density but upregulated ryanodine receptor 2 (RyR2) are major hallmarks of AF. Furthermore, adenosine A2A receptor (A2AR) stimulation increases calcium waves without affecting LTCC and serotonin (5-HT) receptors activation exerts stronger control over myofilaments than over RyR2 function. However, up to date no study has elucidated how the increase on cAMP upon different G-protein-coupled receptors (GPCR) stimulation can lead to different physiological compartmentalized responses. The aim of this study was to investigate the effects of various GPCRs on cAMP levels in different cellular compartments in human atrial myocytes from control patients in sinus rhythm (Ctl), and how these compartmentalized effects are altered in AF. Furthermore, alterations in downstream cAMP level control by phosphodiesterases (PDEs) between patient groups were investigated to further elucidate functional differences.

Methods

Atrial myocytes were isolated from tissues of 66 AF and 80 Ctl patients. Cells were then transduced with adenoviruses (Epac1-camps, pm-Epac1-camps and Epac1-JNC) and cultured for 48 hours to express the Förster-resonance energy transfer (FRET)-based cAMP sensor in the cytosolic, membrane and RyR2 nanodomains, respectively. FRET was then used to measure cAMP in 532 isolated human atrial myocytes. Stimulation with β-adrenergic agonist Isoprenaline (ISO, 100nM) was used and compared with 5-HT (100µM) and A2AR (with CGS, 200nM) stimulation. Additionally, a nonspecific PDE inhibitor (IBMX, 100µM) was applied, as well as PDE3 (Cilostamide, 1µM) and PDE4 (Ro 20-1724, 10µM) specific inhibitors.

Results

A desensitization to β-adrenergic receptor stimulation in AF myocytes was exclusively found in the cytosol, while no difference was seen in neither the RyR2 nor LTCC compartment in AF versus Ctl. Similar effects were observed upon 5-HT stimulation with a significant desensitization in the cytosol, and no difference in the RyR2 compartment. On the contrary, AF myocytes displayed a significantly higher increase in cAMP levels compared to Ctl myocytes in the cytosol upon A2ARs stimulation. Importantly, no effect on cAMP levels was observed in the LTCC compartment after A2ARs or 5-HT stimulation. However, PDE3 inhibition on top of 5-HT stimulation showed a significantly smaller effect on cAMP levels in AF myocytes within the LTCC compartment.

Conclusions

Collectively, our data show that cAMP levels are highly compartmentalized in human atrial myocytes and differentially regulated by different GPCRs. Furthermore, PDEs are to a certain extent responsible for the compartmentalized effects of the different GPCRs.

Characterizing node-negative non-small cell lung cancer patients with similarity networks: A CancerLinQ Discovery analysis

e20585

Background: Patients with node-negative non-small cell lung cancer (NSCLC) whose tumors are completely resected account for approximately 17% of all patients with lung cancer, and disease recurrence occurs in approximately 1 in 5 of these patients. The lack of consensus on factors associated with risk of disease recurrence among node-negative NSCLC patients is a significant barrier to applying precision medicine strategies in this patient population. Clustering similar patients based on distances between various features of data is an emerging topic in precision medicine. Patient similarity networks represent a new model for clustering patients based on heterogeneous data, whereby any data type is converted into a similarity network by defining a similarity measure. The objective of this study was to examine the utility of patient similarity networks to identify NSCLC patients at higher risk of adverse outcomes. Methods: We conducted a retrospective, observational study of 6,020 node-negative NSCLC patients with an initial diagnosis in 2011-2014 in the CancerLinQ Discovery database. A patient similarity network was assembled based on comorbidities and network communities of patients with similar comorbidities at diagnosis were identified. Using Cox proportional-hazards modeling, we examined the extent to which patient age, sex, race, ethnicity, and network community predicted 2-year disease recurrence and 2-year mortality. Results: In the adjusted analyses, patients in the network community enriched for renal disease and congestive heart failure had an 83% increased risk of mortality (95% CI = 1.39-2.41). Patients in the network community enriched for pulmonary disease had a 37% increased risk of mortality (95% CI = 1.06-1.74) yet a lower risk of recurrence (HR = 0.5, 95% CI = 0.34-0.75). After adjusting for comorbidity network community, male patients had a 14% increased risk of mortality (95%CI = 1.02-1.28) and a 21% increased risk of recurrence (95% CI = 1.05-1.40) and black patients had a lower mortality risk (HR = 0.71, 95% CI = 0.58-0.86). Conclusions: Future studies applying patient similar networks to integrate additional diverse and high dimensional data types may afford more clarity in assigning risk of adverse outcomes.

Outcomes of patients with severe mitral regurgitation treated with transcatheter mitral valve implantation or medical therapy

Funding Acknowledgements

Type of funding sources: None.

Background

Patients with severe mitral regurgitation (MR) unsuitable for standard therapy (i.e., open-heart surgery and transcatheter edge-to-edge repair [TEER]), often remain on medical therapy (MT) alone. Transcatheter mitral valve implantation (TMVI) may represent an alternative treatment option for these patients.

Purpose

We aimed to investigate differences in anatomical baseline characteristics and echocardiographic outcomes between MR patients unsuitable for standard therapy, that were either treated with TMVI or remained on MT.

Methods

Between 05/2016-02/2021, 121 high-risk patients with severe MR were evaluated for TMVI. Clinical, echocardiographic and functional outcomes between the subgroups of patients treated with TMVI and MT were compared. The primary combined endpoint was all-cause death or heart failure (HF) hospitalization at 1 year. Subgroup analyses were performed to define specific patient subsets favouring either TMVI or MT.

Results

At baseline, there were no differences between the TMVI group (n = 38) and the MT group (n = 44) regarding age (all TMVI vs. MT: 77.0 years [IQR 72.9, 80.1] vs. 79.0 [IQR 76.0, 81.7], p = 0.13), gender (42.1% female vs. 56.8% female, p = 0.27) and estimated surgical risk (EuroSCORE II 4.4% [IQR 2.8, 13.6] vs. 6.4 [IQR 3.4, 10.1], p = 0.72). Patients undergoing TMVI were more frequently treated for secondary MR (68.4%), while primary MR was the most prevalent MR etiology in patients remaining on medical therapy (50.0%). Left ventricular (LV) end-diastolic diameters (LVEDD) were larger and LV ejection fraction (LVEF) was lower in the TMVI group (LVEDD 58.0mm [IQR 51.4, 65.0], LVEF 37.0% [IQR 31.4, 51.2]) compared to the MT group (LVEDD 52.0mm [IQR 46.2, 58.8], LVEF 54.5% [IQR 40.8, 60.0]) (p = 0.02 for LVEDD, p &lt; 0.001 for LVEF). MR was effectively reduced to ≤ mild MR in all patients undergoing TMVI. In the MT group, MR remained severe in 90% of patients after 1 year. The primary composite endpoint occurred numerically more often in the MT group (72.2%) compared to the TMVI group (51.6%, p = 0.061). Regarding the primary endpoint, the subgroups of patients with LVEF 30-49% (HR 0.28 [95%-CI 0.11-0.67], p = 0.004), effective regurgitant orifice area (EROA) &lt;0.4 cm2 (HR 0.30 [95%-CI 0.13-0.71], p = 0.006), tricuspid annular plane systolic excursion (TAPSE) ≥17mm (HR 0.27 [95%-CI 0.11-0.67], p = 0.005) and New York Heart Association functional class III (HR 0.38 [95%-CI 0.18-0.81], p = 0.012) were more likely to benefit from TMVI compared to MT.

Conclusions

In patients with severe MR unsuitable for standard therapy, TMVI represents a reasonable therapeutic alternative yielding effective elimination of MR. While most patients eligible for TMVI suffer from secondary MR, the majority of patients remaining on MT has primary MR. The primary endpoint occurred numerically, yet not statistically, more often in patients on MT. Baseline echocardiography was able to identify subgroups of patients with beneficial outcome after TMVI.

Cytopenias After CD19 Chimeric Antigen Receptor T-Cells (CAR-T) Therapy for Diffuse Large B-Cell Lymphomas or Transformed Follicular Lymphoma: A Single Institution Experience

INTRODUCTION

Patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL) have poor outcomes. Treatment with CD19 chimeric antigen receptor (CAR-T) cells, tisagenlecleucel and axicabtagene ciloleucel, has been associated with improved outcomes. Cytopenias were observed in clinical trials with both products; however, little is known regarding the patterns and outcomes of these cytopenias.

SUBJECTS AND METHODS

We reviewed DLBCL patients (n=32) receiving either product between January and September 2018 at our institution.

RESULTS

Median duration of leukopenia, neutropenia, lymphopenia, anemia, and thrombocytopenia was 49, 9, 117.5, 125, and 95.5 days after CAR-T infusion, respectively. Filgrastim was used in 63% of patients, and 50% of patients received red cell or platelet transfusions. With the exception of neutropenia, increase in the duration of cytopenia of any lineage was associated with improvement in progression-free survival, and in overall survival in case of anemia. There was no association between the duration of cytopenias with either cytokine release syndrome or neurotoxicity.

DISCUSSION

Our data suggest a correlation between cytopenias and survival outcomes after CD19 CAR-T therapy. If validated, cytopenia may be proven useful as a biomarker of response and survival after CAR-T therapy.

Diagnostic value and prognostic impact of various invasively derived hemodynamic parameters in patients with severe aortic stenosis undergoing TAVI

Background

Ejection time (ET) and Acceleration time (AT) have been described as echocardiographic markers for aortic stenosis (AS).1 Moreover, in a recent study time between invasively measured left ventricular and aortic systolic pressure peaks (T-LVAo) was associated with anatomic AS severity.2 However, the diagnostic value of these parameters has not been validated in a larger patient cohort and their prognostic impact in AS patients undergoing transcatheter aortic valve implantation (TAVI) remains unknown.

Purpose

We aimed to assess the diagnostic value and prognostic impact of ET, AT, and T-LVAo as assessed by invasive measurements in patients undergoing TAVI for severe AS.

Methods

This retrospective single-centre analysis studied 1478 patients undergoing TAVI from 2014 to 2019 for severe AS. All patients received echocardiographic, multislice computed tomography (MSCT) and invasive hemodynamic evaluation with simultaneous pressure measurements in left ventricle and aorta prior to TAVI. Anatomic AS severity was assessed according to MSCT-derived aortic valve calcification density (AVCd) defined as calcium volume per annulus area. All hemodynamic parameters were calculated offline using a dedicated software.

Results

Median patients' age was 81.2 (76.8–84.7) years and 807 (54.6%) were women. Predicted operative risk for mortality was 3.8 (2.6–5.7)% according to STS Score. Medians of invasively derived parameters were 70.0 ms (46.0–98.0) for T-LVAo, 308.0 ms (276.0–336.0) for ET, 180.0 ms (146.0–206.0) for AT. In spline analysis correlation of T-LVAo (Spearman: r=0.35; p&lt;0.001) and ET (Spearman: r=0.18; p&lt;0.001) with AVCd was significant but weak. AT showed negligible correlation with ACVd (Spearman: r=−0.05; p=0.089). The optimal cutoff for death (CD) according to C-statistic was 274 ms for ET and 158 ms for AT. Patients with ET or AT ≥ CD showed lower short and mid-term mortality rates compared to patients with ET or AT &lt; CD (ET ≥ vs. &lt; CD: mortality at 1-year: 14.5 vs. 31.9%, 3-years: 28.3 vs. 53.5%, all p&lt;0.001; AT ≥ vs &lt; CD: mortality at 1-year: 15.5 vs. 25.9%, p&lt;0.001, 3-years: 34.0 vs. 41.0%, p=0.0032). Moreover, multivariate analysis for mortality identified ET (HR 0.58 [95% CI 0.43–0.77; p&lt;0.001]) and AT (HR 0.65 [95% CI 0.49–0.86; p=0.0027]) to be associated with beneficial outcome after TAVI, independent from clinical risk factors and echocardiography-derived parameters like LVEF, mean gradient or stroke volume index. In contrast, T-LVAo showed no prognostic impact according to uni- or multivariate analyses.

Conclusion

T-LVAo provides the highest diagnostic value among the investigational hemodynamic parameters, however correlation with AVCd was weak. ET and AT are strong independent outcome predictors beyond clinical risk factors and standard echocardiographic parameters in AS patients following TAVI. Accordingly, use of ET and AT might improve risk assessment in patients scheduled for TAVI.

Funding Acknowledgement

Type of funding sources: None.

Does industry funding differ between men and women in electrophysiology and devices research?

Funding Acknowledgements

Type of funding sources: None.

Background

A significant gender bias has been identified in cardiology. Industry funding may be important developing electrophysiology (EP) and devices research. Such funding leads to potential conflicts of interest (COI) which must be disclosed on research presentations. There is limited evidence whether the gender bias in cardiology extends to industry funding of research.

Purpose

To assess whether COI disclosures in EP and devices presentations at the ESC Annual Congress differ between men and women.

Methods

Recorded presentations from the Arrhythmia & Devices section of ESC Annual Congresses 2016-2020 were assessed. Presentations were excluded if the original presentation contained no slides, it was a panel discussion, it was a non-scientific presentation, or part of the presentation was missing. Presentations with multiple speakers were also excluded. Chi-squared and Mann-Whitney U tests were used to assess differences between groups for dichotomous and continuous data respectively.

Results

Of 1,153 presentations assessed, 999 were suitable for inclusion. Women made up 22% (n = 221) of presenters. There was no difference in whether COI declaration slides were missing between women (5.9%, n = 13) and men (7.6%, n = 56), p = 0.38. In those with COI disclosure slides (n = 927), women declared significantly lower median number of COIs (0, IQR 0-3) compared with men (2, IQR 0-8), p &lt; 0.0001. In contrast, women spent a greater time-per-word on their COI disclosure slides (250ms, IQR 125-375ms) compared with men (200ms, IQR 118-333ms), p &lt; 0.0001.

Conclusions

Women made up a minority of presenters in EP/devices talks at the ESC annual congress. Women were less likely to have COIs which may suggest that they are less likely to receive industry funding. Despite this, women spent a greater amount of time-per-word on their COI slides. The lower number of declared COIs in women highlights another potential area of gender bias in cardiology that needs further investigation so that it can be addressed.

Surgeon and medical oncologist peer network effects on the uptake of the 21-gene breast cancer recurrence score assay

BACKGROUND

Drivers behind the adoption of gene expression profiling in breast cancer oncology have been shown to include exposure to physician colleagues' use of a given genomic test. We examined adoption of the Oncotype DX 21-gene breast cancer recurrence score assay (ODX) in the United States after its incorporation into clinical guidelines. The influence of patient-sharing ties and co-location with prior adopters and the role of these potential exposures across medical specialties on peers' adoption of the test were examined.

METHODS

We conducted a retrospective cohort study of women with incident breast cancer using a 100% sample of fee-for-service Medicare enrollee claims over 2008-2011. Peer networks connecting medical oncologists and surgeons treating these patients were constructed using patient-sharing and geographic co-location. The impact of peer connections on the adoption of ODX by physicians and testing of patients was modeled with multivariable hierarchical regression.

RESULTS

Altogether, 156,229 women identified with incident breast cancer met criteria for cohort inclusion. A total of 7689 ODX prescribing physicians were identified. Co-location with medical oncologists who adopted the test in the early period (2008-2009) was associated with a 1.38-fold increase in the odds of a medical oncologist adopting ODX in 2010-2011 (95% CI = 1.04-1.83), as was co-location with early-adopting surgeons (odds ratio [OR] = 1.25, 95% CI = 1.00-1.58). Patients whose primary medical oncologist was linked to an early-adopting surgeon through co-location (OR = 1.17, 95% CI = 1.04-1.32) or both patient-sharing and co-location (OR = 1.17, 95% CI = 1.03-1.34) were more likely to receive ODX.

CONCLUSIONS

Exposure to surgeon early adopters through peer networks and co-location was predictive of ODX uptake by medical oncologists and testing of patients. Interventions focused on the role of surgeons in molecular testing may improve the implementation of best practices in breast cancer care.

Prevalence and prognostic impact of left ventricular outflow tract calcification in patients with severe aortic stenosis undergoing transfemoral TAVI using second-generation devices

Introduction

Left ventricular outflow tract (LVOT) calcification is known to be associated with adverse outcomes after TAVI in patients receiving first-generation transcatheter heart valves (THV). Second-generation THV have been shown to improve outcomes of TAVI patients. Thus, aim of this study is to assess the prevalence of LVOT calcification as well as its impact on procedural and clinical outcomes in patients with severe aortic stenosis undergoing transfemoral TAVI with second-generation THV in a real-world patient cohort.

Methods

In this retrospective single-center analysis patients receiving transfemoral TAVI with second-generation THV for the treatment of aortic stenosis (AS) between 05/2012 and 06/2018 and with adequate CT data were included (n=836). Amount of LVOT calcification was measured quantitatively from contrast-enhanced multislice CT using a dedicated software. Baseline characteristics and outcomes were compared according to presence of significant LVOT calcification (none/≤10 mm3 vs. &gt;10 mm3). Procedural and clinical outcome were assessed in accordance with VARC-2 criteria. All-cause mortality was assessed by Kaplan-Meier method, median follow-up was 1.4 years.

Results

Significant LVOT calcification was present in 37.0% of patients. Patients with LVOT calcification were older (all results as follows without (w/o) vs. with (w) LVOT calcification: 81.4 (77.1, 84.8) vs. 82.3 (78.0, 86.3) years, p=0.006), but presented similar STS scores compared to those without LVOT calcification (5.4±4.7 vs. 5.4±3.5%, p=0.94). Moreover, patients with LVOT calcification had higher mean transvalvular gradients at baseline (30.0 (21.0, 41.0) vs. 37.0 (25.7, 47.0) mmHg, p&lt;0.001) and higher aortic valve calcium volume (380.7 (226.8, 632.1) vs. 663.6 (364.5, 1070.3) mm3, p&lt;0.001). There were no significant differences in rate of device success (97.0 vs. 94.2%, p=0.11), renal failure (2.6 vs. 2.3%, p=1.00), myocardial infarction (0.9 vs. 1.2%, p=1.00) or rate of permanent pacemaker implantation at 30 days after TAVI (16.6 vs. 17.2%, p=0.91). However, rate of TIA/stroke was significantly higher in patients with LVOT calcification (2.1 vs. 6.2%, p=0.0098). Furthermore, patients with LVOT calcification had a higher rate of more than mild paravalvular leakage at discharge (3.8 vs. 7.6%, p=0.033). Rate of 1 year all-cause mortality (17.8 vs. 21.2%, p=0.23) was not significantly different between both groups.

Conclusions

Significant LVOT calcification is present in a substantial proportion of patients receiving TAVI. In such patients, higher rates of cerebrovascular events and more than mild PVL occurred compared to those without significant LVOT calcification even with currently available second-generation THV. Although these findings did not translate into higher mortality rates in the present study, they underline the need for further optimization of THV technology in order to improve outcomes among all TAVI patients.

Figure 1. 1-year mortality

Funding Acknowledgement

Type of funding source: None

Patient and physician factors associated with Oncotype DX and adjuvant chemotherapy utilization for breast cancer patients in New Hampshire, 2010-2016

BACKGROUND

Oncotype DX® (ODX) is used to assess risk of disease recurrence in hormone receptor positive, HER2-negative breast cancer and to guide decisions regarding adjuvant chemotherapy. Little is known about how physician factors impact treatment decisions. The purpose of this study was to examine patient and physician factors associated with ODX testing and adjuvant chemotherapy for breast cancer patients in New Hampshire.

METHODS

We examined New Hampshire State Cancer Registry data on 5630 female breast cancer patients diagnosed from 2010 to 2016. We performed unadjusted and adjusted hierarchical logistic regression to identify factors associated with a patient's receipt of ODX, being recommended and receiving chemotherapy, and refusing chemotherapy. We calculated intraclass correlation coefficients (ICCs) to examine the proportion of variance in clinical decisions explained by between-physician and between-hospital variation.

RESULTS

Over the study period, 1512 breast cancer patients received ODX. After adjustment for patient and tumor characteristics, we found that patients seen by a male medical oncologist were less likely to be recommended chemotherapy following ODX (OR = 0.50 (95% CI = 0.34-0.74), p < 0.01). Medical oncologists with more clinical experience (reference: less than 10 years) were more likely to recommend chemotherapy (20-29 years: OR = 4.05 (95% CI = 1.57-10.43), p < 0.01; > 29 years: OR = 4.48 (95% CI = 1.68-11.95), p < 0.01). A substantial amount of the variation in receiving chemotherapy was due to variation between physicians, particularly among low risk patients (ICC = 0.33).

CONCLUSIONS

In addition to patient clinicopathologic characteristics, physician gender and clinical experience were associated with chemotherapy treatment following ODX testing. The significant variation between physicians indicates the potential for interventions to reduce variation in care.

A biomechanical comparison of conventional classifications of bowling action-types in junior fast bowlers

Fast bowling is categorised into four action types: side-on, front-on, semi-open and mixed; however, little biomechanical comparison exists between action types in junior fast bowlers. This study investigated whether there are significant differences between action-type mechanics in junior fast bowlers. Three-dimensional kinematic and kinetic analyses were completed on 60 junior male fast bowlers bowling a five-over spell. Mixed-design factorial analyses of variance were used to test for differences between action-type groups across the phases of the bowling action. One kinetic difference was observed between groups, with a higher vertical ground reaction force loading rate during the front-foot contact phase in mixed and front-on compared to semi-open bowlers; no other significant group differences in joint loading occurred. Significant kinematic differences were observed between the front-on, semi-open and mixed action types during the front-foot contact phase for the elbow and trunk. Significant kinematic differences were also present for the ankle, T12-L1, elbow, trunk and pelvis during the back-foot phase. Overall, most differences in action types for junior fast bowlers occurred during the back-foot contact phase, particularly trunk rotation and T12-L1 joint angles/ranges of motion, where after similar movement patterns were utilized across groups during the front-foot contact phase.

Quantification of Plasma and Urine Thymidine and 2'-Deoxyuridine by LC-MS/MS for the Pharmacodynamic Evaluation of Erythrocyte Encapsulated Thymidine Phosphorylase in Patients with Mitochondrial Neurogastrointestinal Encephalomyopathy

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an ultra-rare disorder caused by mutations in TYMP, leading to a deficiency in thymidine phosphorylase and a subsequent systemic accumulation of thymidine and 2'-deoxyuridine. Erythrocyte-encapsulated thymidine phosphorylase (EE-TP) is under clinical development as an enzyme replacement therapy for MNGIE. Bioanalytical methods were developed according to regulatory guidelines for the quantification of thymidine and 2'-deoxyuridine in plasma and urine using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for supporting the pharmacodynamic evaluation of EE-TP. Samples were deproteinized with 5% perchloric acid (v/v) and the supernatants analyzed using a Hypercarb column (30 × 2.1 mm, 3 µm), with mobile phases of 0.1% formic acid in methanol and 0.1% formic acid in deionized water. Detection was conducted using an ion-spray interface running in positive mode. Isotopically labelled thymidine and 2'-deoxyuridine were used as internal standards. Calibration curves for both metabolites showed linearity (r > 0.99) in the concentration ranges of 10-10,000 ng/mL for plasma, and 1-50 µg/mL for urine, with method analytical performances within the acceptable criteria for quality control samples. The plasma method was successfully applied to the diagnosis of two patients with MNGIE and the quantification of plasma metabolites in three patients treated with EE-TP.

Surveillance imaging for patients with head and neck cancer treated with definitive radiotherapy: A partially observed Markov decision process model

BACKGROUND

A possible surveillance model for patients with head and neck cancer (HNC) who received definitive radiotherapy was created using a partially observed Markov decision process. The goal of this model is to guide surveillance imaging policies after definitive radiotherapy.

METHODS

The partially observed Markov decision process model was formulated to determine the optimal times to scan patients. Transition probabilities were computed using a data set of 1508 patients with HNC who received definitive radiotherapy between the years 2000 and 2010. Kernel density estimation was used to smooth the sample distributions. The reward function was derived using cost estimates from the literature. Additional model parameters were estimated using either data from the literature or clinical expertise.

RESULTS

When considering all forms of relapse, the model showed that the optimal time between scans was longer than the time intervals used in the institutional guidelines. The optimal policy dictates that there should be less time between surveillance scans immediately after treatment compared with years after treatment. Comparable results also held when only locoregional relapses were considered as relapse events in the model. Simulation results for the inclusive relapse cases showed that <15% of patients experienced a relapse over a simulated 36-month surveillance program.

CONCLUSIONS

This model suggests that less frequent surveillance scan policies can maintain adequate information on relapse status for patients with HNC treated with radiotherapy. This model could potentially translate into a more cost-effective surveillance program for this group of patients.

P962Follow-up of protected high-risk percutaneous coronary intervention with microaxial Impella pump. Results from the retrospective German Impella Registry

Background

Percutaneous coronary intervention (PCI) presents a relevant alternative to coronary bypass surgery for the treatment of patients with complex coronary artery disease and high perioperative risk. By temporary implantation of a percutaneous ventricular assist devices (pVAD) interventionalists attempt to anticipate the hemodynamic risk of those high-risk patients in a so-called protected PCI. The Impella® system presents the currently most common device for protected PCI and could show hemodynamic stability in earlier trials.

Methods

This study is a retrospective, observational multi-center registry of ten hospitals in Germany. We included patients undergoing protected high-risk PCI with Impella® support. The primary endpoint was defined as major adverse cardiac events (MACE) during a 180-day follow-up and consisted of all-cause mortality, myocardial infarction (MI) and stroke.

Results

Six of the participating hospitals performed a follow-up. In total, 157 patients (80.3% male; mean age 71.8±10.8 years) were included in the present study. Prior to PCI, median left ventricular ejection fraction was 39.0% (25.0%-50.0%) and median SYNTAX-Score I was 33.0 (24.0–40.5). The 180-day follow-up was available for 149 patients (94.9%). Eight patients (5.1%) were lost to follow-up. During the follow-up period, 34 patients (22.8%) suffered from a MACE. A total of 27 patients (18.1%) died. Nine patients (6.0%) sustained a MI, while 4 patients (2.7%) had a stroke.

Kaplan-Meier curves for primary endpoint

Conclusions

Patients undergoing protected high-risk PCI with Impella® support show a good 180-day clinical outcome regarding rates of MACE and mortality. However, a head-to-head comparison of Impella supported patients to protected PCI with other pVADs is pending.

Acknowledgement/Funding

S.B., N.W., F.A.-R., J.-M.S., A.S., R.S., I.A. receive consulting fees/honoraria from Abiomed (Danvers, MA, USA).

P1706Neurological outcome in patients with out-of-hospital cardiac arrest undergoing a standardised protocol including therapeutic hypothermia and routine coronary angiography

Purpose

To establish cut-offs for neuromarkers such as neuron-specific enolase (NSE) and S-100 predicting good neurological outcome for patients treated with therapeutic hypothermia with out-of-hospital cardiac arrest (OHCA) and return of spontaneous circulation (ROSC) as current cut-offs had been derived from normothermic cohorts.

Methods

Consecutive data of all patients with OHCA admitted to our institution between 01/2011 and 12/2016 were collected in a database. Patient received standard intensive care according to the Hannover Cardiac Resuscitation Algorithm (HaCRA) including mandatory hypothermia. Neurological markers such as neuron-specific enolase (NSE) and S-100 have been used to assess neurological damage following OHCA.

Results

Mean age of overall patient population (n=302) was 63±14 [54–74] years with a male predominance (77%). Cardiac arrest was witnessed in 81% and bystander cardiopulmonal resuscitation (CPR) was performed in 67%. Initial rhythm was ventricular fibrillation in 69%. ROSC had been achieved after 24±17 minutes. Hypothermia was applied in all patients. In 95% percutaneous coronary angiography and in 57% of them coronary intervention was performed. After ROSC, STEMI was present in 44%. Mechanical support was required in 19%. 30 day mortality was 44% in the total cohort. Mean NSE was 27±69 μg/l, mean NSE with good neurological outcome was 20±8.7 μg/l, highest NSE with good neurological outcome was 46 μg/l. Mean S-100 was 0.114±2.037μg/l, mean S-100 with good neurological outcome was 0.068±0.067 μg/l, highest S-100 with good neurological outcome was 0.360 μg/l.

Conclusion

Even when using a strict protocol for OHCA patients and routinely applying therapeutic hypothermia, the cut-offs for NSE and S-100 regarding good neurological outcome are similar to those reported before without therapeutic hypothermia, but they must not be used solitary to withdraw life support as even very high markers can be associated with goof neurological outcome in individual patients.

P5736Mortality in infarct-related cardiogenic shock patients treated with an microaxial pump: influence of timing and predicted risk

Background

In-hospital mortality in acute myocardial infarction-related cardiogenic shock (AMI-CS) remains high at ∼40%. No prospective trials have been finished investigating the influence of mechanical support in AMI-CS. We compared observed to individually predicted mortality using CardShock-, Shock II-, and SAVE-scores in AMI-CS patients treated between 2013 and 2017 with an Impella microaxial pump, who met the IABP-Shock II-trials inclusion/exclusion criteria in order to determine whether standardised use of an Impella microaxial flow-pump in AMI-CS is associated with lower than predicted mortality rates and whether timing of implantation or selecting patients based on predicted risk is meaningful.

Methods

We analyzed data from 166 consecutive AMI-CS patients meeting the inclusion/exclusion criteria of the IABP-Shock II-trial (age 65±12 years), who received an Impella microaxial pump and compared observed vs. individually predicted mortality using CardShock-, Shock II-, and SAVE-scores. 39% (n=65) had been resuscitated before Impella implantation.

Results

Overall 30-day mortality was 43%. Mortality was higher in resuscitated patients (50% vs. 36%, p=0.0324) and when Impella was implanted post-PCI (Impella-pre-PCI: 29%, Impella-post-PCI: 50%, p=0.0130). In all score systems predicted mortality was significantly higher than observed mortality on Impella support for individuals with highest predicted risk (IABP-Shock II predicted 77% vs observed 44%, p=0.010; CardShock predicted 77% vs observed 51%, p=0.017; SAVE predicted 81% vs observed 56%, p<0.001).

Conclusion

In the absence of prospective trials, our retrospective analysis encourages the use of active mechanical circulatory support by Impella microaxial pumps in high-risk patients with AMI-CS and supports the concept of early implantation prior to PCI.

Macronutrient variability in human milk from donors to a milk bank: Implications for feeding preterm infants

Background and objective

The composition of human milk varies widely and impacts the ability to meet nutrient requirements for preterm infants. The purpose of this study is to use a large dataset of milk composition from donors to a milk bank to: (1) describe the macronutrient variability in human milk and how it contributes to the ability to meet the protein and calorie targets for the preterm infant using fortification with commercially available multi-nutrient fortifiers; (2) assess how temporal versus subject effects explain macronutrient variability; (3) determine how macronutrient variability contributes to the nutrient distribution in pooled donor milk.

Methods

This is a retrospective, observational study that analyzes the macronutrient data of 1,119 human milk samples from 443 individual donors to a milk bank. We test fortification strategies with potential basic, intermediate, and high protein and calorie commercial fortifiers. Additionally, we simulate the random pooling of multiple donors to model the impact of macronutrient variability on pooled donor milk.

Results

Fat was the most variable nutrient and accounted for 80% of the difference in calories. A subject-effect predicted more of the variability after 4 weeks postpartum in all macronutrients (R² > = 0.50) than a time-effect (R² < = 0.28). When pooling multiple donors, variability was reduced by increasing the number of donors randomly selected for a pool or targeted pooling based on macronutrient analysis of donor pools. Over 75% of mature milk samples fortified with a basic protein fortifier did not meet daily protein targets of 3.5 g/kg without exceeding volumes of 160 ml/kg/day.

Conclusion

There is a strong individual signature to human milk that impacts the pooling of donor milk, and the ability to meet protein and energy requirements for the preterm infant with basic and intermediate protein and calorie fortifiers.

Defect-Induced Water Bilayer Growth on Anatase TiO2(101)

Preparing an anatase TiO₂(101) surface with a high density of oxygen vacancies and associated reduced Ti species in the near-surface region results in drastic changes in the water adsorption chemistry compared to adsorption on a highly stoichiometric surface. Using synchrotron radiation excited photoelectron spectroscopy, we observe a change in the water growth mode, from layer-by-layer growth on the highly stoichiometric surface to bilayer growth on the reduced surface. Furthermore, we have been able to observe Ti³⁺ enrichment at the surface upon water adsorption. The Ti³⁺ enrichment occurs concomitant with effective water dissociation into hydroxyls with a very high thermal stability. The water bilayer on the reduced surface is thermally more stable than that on the stoichiometric surface, and it is more efficient in promoting further water dissociation upon heating. The results thus show how the presence of subsurface defects can alter the wetting mechanism of an oxide surface.

Human Cerebellar Sub-millimeter Diffusion Imaging Reveals the Motor and Non-motor Topography of the Dentate Nucleus

The reciprocal cortico-cerebellar loops that underlie cerebellar contributions to motor and cognitive behavior form one of the largest systems in the primate brain. Work with non-human primates has shown that the dentate nucleus, the major output nucleus of the cerebellum, contains topographically distinct connections to both motor and non-motor regions, yet there is no evidence for how the cerebellar cortex connects to the dentate nuclei in humans. Here we used in-vivo sub-millimeter diffusion imaging to characterize this fundamental component of the cortico-cerebellar loop, and identified a pattern of superior motor and infero-lateral non-motor connectivity strikingly similar to that proposed by animal work. Crucially, we also present first evidence that the dominance for motor connectivity observed in non-human primates may be significantly reduced in man - a finding that is in accordance with the proposed increase in cerebellar contributions to higher cognitive behavior over the course of primate evolution.

Analysis of Minimally Invasive Left Thoracotomy HVAD Implantation – A Single-Center Experience

Background Minimally invasive left ventricular assist device (LVAD) implantation may reduce peri-/postoperative complications and risks associated with resternotomies. In this study, we describe our first results using a minimally invasive LVAD implantation technique (lateral thoracotomy [LT] group). These results were compared with LVAD implantations done via full median sternotomy (STX group).

Methods HVAD (HeartWare, Framingham, Massachusetts, United States) implantations in 70 patients (LT group n = 22, 52 ± 15 years old; STX group n = 48, 59 ± 11 years old) were retrospectively analyzed. Minimally invasive access via left thoracotomy was feasible in 22 patients. Peri- and postoperative analyses of survival and adverse events were performed.

Results No survival differences were observed between the LT and STX group (p = 0.43). LT patients without temporary right ventricular assist device (tRVAD) showed a significantly better survival rate compared to LT patients with concomitant tRVAD implantation (p = 0.02), which could not be demonstrated in the STX group (p = 0.11). Two LT and four STX patients were successfully bridged to heart transplantation and three STX patients were successfully weaned with subsequent LVAD explantations. LVAD-related infections (n = 4 LT group vs n = 20 STX group, p = 0.04) were less likely in the LT group. No wound dehiscence occurred in the LT group, whereas five were observed in the STX group (p = 0.17). The amount of perioperative blood transfusions (within the first 7 postoperative days) did not differ in both study groups (p = 0.48).

Conclusion The minimally invasive approach is a viable alternative with the possibility to reduce complications and should be particularly considered for bridge-to-transplant patients.

A randomized, controlled, double-blind, multi-center trial to evaluate the efficacy and safety of a liquid containing ivy leaves dry extract (EA 575®) vs. placebo in the treatment of adults with acute cough

This randomized, placebo-controlled, double-blind trial was conducted to assess the efficacy and safety of ivy leaves cough liquid in the treatment of acute cough. A total of 181 adult patients with acute cough were treated with either ivy leaves cough liquid containing EA 575® or with placebo three times a day for one week. The primary efficacy outcome was cough severity (CS) assessed by Visual Analogue Scale (VAS) over the whole treatment period (area-under-the-curve (AUC0-168 h) over 7 days (visit (V)1, V2, V3, V4, and V5). The secondary endpoints were defined as the CS assessed by VAS over the whole observation period (V1 - V6) and by Bronchitis Severity Score (BSS) and Verbal Category Descriptive (VCD) score. The evaluation of the VAS, BSS and VCD score revealed that subjects treated with ivy leaves cough liquid showed statistically significant and clinically relevant reductions in CS, severity of symptoms associated with cough and bronchitis compared to the placebo group. Furthermore, a remarkable early onset of efficacy was observed as significant reductions of cough severity were detected within 48 hours after the first drug intake. At all following visits and even 7 days after the end of treatment (V6) this significant treatment advantage was detected in comparison to placebo. All adverse events (AEs) in this clinical trial were non-serious, mild or of moderate severity and not drug-related. This clinical trial proved consistent superiority of the ivy leaves cough liquid treatment versus placebo and confirmed the EA 575® preparation to be a safe and efficacious option for the treatment of acute cough.

Die Strahlenexposition des Patienten durch die Transmissionsmessung bei der Myokardperfusions-SPECT

Ziel: Ziel war die Bestimmung der Strahlenexposition des Patienten durch die Transmissionsmessung bei der Myokardperfusions-SPECT. Methode und Material: Simultan zur Emissionsmessung (Tc-99m-MIBI, A = 500 MBq) erfolgt bei der Myokardperfusions-SPECT eine Transmissionsmessung mit Hilfe einer Am-241-Linienquelle (A = 5550 MBq). Bei der Simulation der Myokardperfusions-SPECT (ohne Tc-99m-MIBI) wurden Dosismessungen mit Thermolumineszenzdosimetem unter Verwendung eines Thoraxphantoms durchgeführt. Ergebnisse: Bei einer Aufnahmedauer von 20 min ergaben sich folgende Energiedosen: Oberfläche (Xyphoid) 30 μGy, Herz 25 μGy, Lunge 14 μGy, 2. BWK 16 μGy, oberes anteriores Mediastinum 16 μGy, Leber 0 μGy. Eine Abschätzung des Verhältnisses zwischen den effektiven Dosen durch Transmissions- und Emissionsmessung (3,6 x 10-3 bzw. 4,1 mSv) ergab einen Wert von 9 x 10-4. Schlußfolgerung: Die Strahlenexposition des Patienten durch die Transmissionsmessung ist vernachlässigbar gering und damit kein limitierender Faktor im Hinblick auf die generelle Anwendung der Transmissionsmessung bei der klinischen Myokardperfusions-SPECT.

Radiation exposure to the patient caused by single-photon transmission measurement for 3D whole-body PET

Aim: The aim of the study was the determination of the radiation exposure to the patient caused by singlephoton transmission mesasurement for 3D whole-body PET. Material and Method: Single-photon-transmission measurement is performed using two Cs-137 pointsources (Eγ = 662 keV, A = 2*614 MBq) on a 3D PET scanner (ECAT ART). During a simulation of a whole body transmission scan (axial length: 75 cm, 6 contigous bed positions) dose measurements with thermoluminescent dosimeters were carried out using a thorax and an abdomen phantom. Following the guidelines of the ICRU report No. 60 an estimation of the effective dose caused by a single-photon transmission measurement was calculated. Results: For a total acquisition time of 360 min (6 beds with an acquisition time of 60 min per bed) the absorbed doses amounted to: surface (xyphoid) 189 μGy, heart 196 μGy, lungs 234 μGy, vertebra 240 μGy, liver 204 μGy, gonads 205 μGy, thyroid 249 μGy and bladder 185 μGy resulting in a conversion factor of 1.7*10–4 mSv/( h*MBq). The estimation of the effective dose for a patient’s transmission (acquisition time of 3.2 min per bed) yields a value of 11 μSv. An estimation of the ratio of the conversion factors for transmission measurements in single-photonand in coincidence mode (two Ge-68/Ga-68 rod sources of 40 MBq each), respectively, resulted in a value of 0.18. The comparison of the effective doses caused by single-photon transmission and by emission measurement (injection of 250 MBq of FDG) yields a ratio of 2.3*10–3. Conclusion: The radiation exposure of the patient caused by the transmission measurement for 3D whole-body-PET can be neglected. In comparison with the coincidence-transmission using uncollimated line sources of low activity the radiation exposure is still reduced using single photon transmission with collimated point sources of high activity.

Physical aspects of scintigraphybased dosimetry for nuclear medicine therapy

In nuclear medicine therapy the treatment of tumours by radiation exposure from internally deposited labelled antibodies or labelled peptides is currently an active field of investigation. To permit the efficient delivery of high amounts of radiation dose to tumours while limiting the radiation dose to critical organs dosimetry calculations have to be performed. These are relying on scintigraphic data being input to the well known MIRD formalism.

This paper focuses on the methods and the difficulties associated with the scintigraphic determination of organ kinetics. The physical properties of the well-known scintigraphic imaging modalities, PET, SPECT and planar scintigraphy, are discussed thereby taking into account the properties of the appropriate radionuclides currently being available for therapy and dosimetry. Several arguments are given and disputed for the limited clinical use of PET and SPECT in dosimetry and the ongoing preference of planar whole-body imaging as the method of choice. The quantitative restrictions still inherent to this method are also discussed in detail. Procedural recommendations are proposed covering all processes related to data acquisition, data correction and data analysis which finally lead to reliable estimations of organ dose.

Para-[123I]iodo-L-phenylalanine in patients with pancreatic adenocarcinoma

Recently, p-[123I]iodo-L-phenylalanine (IPA) was clinically validated for brain tumour imaging. Preclinical studies demonstrated uptake of IPA into pancreatic adenocarcinoma suggesting its diagnostic application in patients with pancreatic tumours. The aim was to study the tumour uptake of IPA in patients with pancreatic adenocarcinoma and to analyse its biodistribution and dosimetry to assess the radiation dose resulting from its diagnostic use. Patients, methods: Seven patients with pancreatic adenocarcinoma underwent whole-body scintigraphies and SPECT up to 24 h after administration of 250 MBq of IPA. Tumour uptake of IPA was assessed visually. Time activity curves and the corresponding residence times were determined for whole-body, kidneys, liver, spleen, lung, heart content, brain, and testes. Mean absorbed doses for various organs and the effective dose were assessed based on the MIRD formalism using OLINDA/EXM. Results: IPA exhibited no accumulation in proven manifestations of pancreatic adenocarcinomas. IPA was exclusively eliminated by the urine and showed a delayed clearance from blood. Residence times were 0.26 ± 0.09 h for kidneys, 0.38 ± 0.19 h for liver, 0.15 ± 0.07 h for spleen, 0.51 ± 0.20 h for lungs, 0.22 ± 0.07 h for heart content, 0.11 ± 0.05 h for brain, 0.014 ± 0.005 h for testes and 6.4 ± 2.2 h for the remainder. The highest absorbed doses were determined in the urinary bladder wall and in the kidneys. According to the ICRP 60 the effective dose resulting from 250 MBq IPA was 3.6 ± 0.7 mSv. Conclusion: Para-[123I]iodo-L-phenylalanine can be used in diagnostic nuclear medicine with acceptable radiation doses. Besides its proven validity for brain tumour imaging, IPA does not appear to be suitable as tracer for pancreatic cancer.

Atypical periodic paralysis and myalgia: A novel RYR1 phenotype

Objective

To characterize the phenotype of patients with symptoms of periodic paralysis (PP) and ryanodine receptor (RYR1) gene mutations.

Methods

Cases with a possible diagnosis of PP but additional clinicopathologic findings previously associated with RYR1-related disorders were referred for a tertiary neuromuscular clinical assessment in which they underwent detailed clinical evaluation, including neurophysiologic assessment, muscle biopsy, and muscle MRI. Genetic analysis with next-generation sequencing and/or targeted Sanger sequencing was performed.

Results

Three cases with episodic muscle paralysis or weakness and additional findings compatible with a RYR1-related myopathy were identified. The McManis test, used in the diagnosis of PP, was positive in 2 of 3 cases. Genetic analysis of known PP genes was negative. RYR1 analysis confirmed likely pathogenic variants in all 3 cases.

Conclusions

RYR1 mutations can cause late-onset atypical PP both with and without associated myopathy. Myalgia and cramps are prominent features. The McManis test may be a useful diagnostic tool to indicate RYR1-associated PP. We propose that clinicopathologic features suggestive of RYR1-related disorders should be sought in genetically undefined PP cases and that RYR1 gene testing be considered in those in whom mutations in SCN4A, CACNA1S, and KCNJ2 have already been excluded.