Characteristics and anatomic location of PD-1+TCF1+ stem-like CD8 T cells in chronic viral infection and cancer.

CD8 T cells play an essential role in antitumor immunity and chronic viral infections. Recent findings have delineated the differentiation pathway of CD8 T cells in accordance with the progenitor-progeny relationship of TCF1+ stem-like and Tim-3+TCF1- more differentiated T cells. Here, we investigated the characteristics of stem-like and differentiated CD8 T cells isolated from several murine tumor models and human lung cancer samples in terms of phenotypic and transcriptional features as well as their location compared to virus-specific CD8 T cells in the chronically lymphocytic choriomeningitis virus (LCMV)-infected mice. We found that CD8 tumor-infiltrating lymphocytes (TILs) in both murine and human tumors exhibited overall similar phenotypic and transcriptional characteristics compared to corresponding subsets in the spleen of chronically infected mice. Moreover, stem-like CD8 TILs exclusively responded and produced effector-like progeny CD8 T cells in vivo after antigenic restimulation, confirming their lineage relationship and the proliferative potential of stem-like CD8 TILs. Most importantly, similar to the preferential localization of PD-1+ stem-like CD8 T cells in T cell zones of the spleen during chronic LCMV infection, we found that the PD-1+ stem-like CD8 TILs in lung cancer samples are preferentially located not in the tumor parenchyma but in tertiary lymphoid structures (TLSs). The stem-like CD8 T cells are present in TLSs located within and at the periphery of the tumor, as well as in TLSs closely adjacent to the tumor parenchyma. These findings suggest that TLSs provide a protective niche to support the quiescence and maintenance of stem-like CD8 T cells in the tumor.

Burden of bacterial antimicrobial resistance in low-income and middle-income countries avertible by existing interventions: an evidence review and modelling analysis.

National action plans enumerate many interventions as potential strategies to reduce the burden of bacterial antimicrobial resistance (AMR). However, knowledge of the benefits achievable by specific approaches is needed to inform policy making, especially in low-income and middle-income countries (LMICs) with substantial AMR burden and low health-care system capacity. In a modelling analysis, we estimated that improving infection prevention and control programmes in LMIC health-care settings could prevent at least 337 000 (95% CI 250 200-465 200) AMR-associated deaths annually. Ensuring universal access to high-quality water, sanitation, and hygiene services would prevent 247 800 (160 000-337 800) AMR-associated deaths and paediatric vaccines 181 500 (153 400-206 800) AMR-associated deaths, from both direct prevention of resistant infections and reductions in antibiotic consumption. These estimates translate to prevention of 7·8% (5·6-11·0) of all AMR-associated mortality in LMICs by infection prevention and control, 5·7% (3·7-8·0) by water, sanitation, and hygiene, and 4·2% (3·4-5·1) by vaccination interventions. Despite the continuing need for research and innovation to overcome limitations of existing approaches, our findings indicate that reducing global AMR burden by 10% by the year 2030 is achievable with existing interventions. Our results should guide investments in public health interventions with the greatest potential to reduce AMR burden.

Cutting Edge: Polycomb Repressive Complex 1 Subunit Cbx4 Positively Regulates Effector Responses in CD8 T Cells.

CTL differentiation is controlled by the crosstalk of various transcription factors and epigenetic modulators. Uncovering this process is fundamental to improving immunotherapy and designing novel therapeutic approaches. In this study, we show that polycomb repressive complex 1 subunit chromobox (Cbx)4 favors effector CTL differentiation in a murine model. Cbx4 deficiency in CTLs induced a transcriptional signature of memory cells and increased the memory CTL population during acute viral infection. It has previously been shown that besides binding to H3K27me3 through its chromodomain, Cbx4 functions as a small ubiquitin-like modifier (SUMO) E3 ligase in a SUMO-interacting motifs (SIM)-dependent way. Overexpression of Cbx4 mutants in distinct domains showed that this protein regulates CTL differentiation primarily in an SIM-dependent way and partially through its chromodomain. Our data suggest a novel role of a polycomb group protein Cbx4 controlling CTL differentiation and indicated SUMOylation as a key molecular mechanism connected to chromatin modification in this process.

Comparison of bare and nonbare stent grafts during thoracic endovascular aneurysm repair of the aortic arch.

OBJECTIVE: We compared the outcomes of patients treated with nonbare stents (NBS) and proximal bare stents (PBS) endografts with a proximal landing zone in the aortic arch during thoracic endovascular aortic repair (TEVAR). METHODS: We conducted a retrospective cohort, observational, multicenter study that included 361 consecutive TEVAR procedures undertaken between November 2005 and December 2021. TEVAR patients with both BS and NBS Relay stent graft configurations with proximal landing in zones 1, 2, or 3 were enrolled. Preoperative anamnestic and morphological data, clinical outcomes, and aortic modifications 30 days after surgery and at the latest follow-up available were collected. The primary outcome was freedom from proximal endoleak (type IA) comparing the two configurations. Total and detailed endoleak rates, clinical and technical success, intraoperative additional maneuvers, major adverse events, and reinterventions were secondary outcomes. RESULTS: The median follow-up was 4.9 (interquartile range, 2.0-8.1) years. No statistically significant difference between NBS and PBS patients concerning 30-day major adverse events, retrograde aortic dissection, disabling stroke, or late type IA endoleak (10.8% vs 7.8%; P = .597). Aneurysmal disease (P = .026), PLZ diameter of >34 mm (P = .026), aortic tortuosity index of >1.4 (P = .008), type III aortic arch (P = .068), and PLZ thrombus (P = .014) identified as risk factors by univariate Cox regression analysis. PLZ thrombus was the only type IA endoleak risk factor at multivariate Cox regression (P = .016). CONCLUSIONS: We found no statistically significant difference in freedom from type IA endoleak, retrograde dissection, or disabling stroke observed between the NBS and the BS configuration of the Relay endograft. Proximal landing zone thrombotic apposition was a prominent risk factor for type IA endoleak after TEVAR.

The accuracy and intra- and interobserver variability of PSMA PET/CT for the local staging of primary prostate cancer.

PURPOSE: Prostate-specific membrane antigen (PSMA) positron emission tomography/ computed tomography (PET/CT) is recognized as the most accurate imaging modality for detection of metastatic high-risk prostate cancer (PCa). Its role in the local staging of disease is yet unclear. We assessed the intra- and interobserver variability, as well as the diagnostic accuracy of the PSMA PET/CT based molecular imaging local tumour stage (miT-stage) for the local tumour stage assessment in a large, multicentre cohort of patients with intermediate and high-risk primary PCa, with the radical prostatectomy specimen (pT-stage) serving as the reference standard. METHODS: A total of 600 patients who underwent staging PSMA PET/CT before robot-assisted radical prostatectomy was studied. In 579 PSMA positive primary prostate tumours a comparison was made between miT-stage as assessed by four nuclear physicians and the pT-stage according to ISUP protocol. Sensitivity, specificity and diagnostic accuracy were determined. In a representative subset of 100 patients, the intra-and interobserver variability were assessed using Kappa-estimates. RESULTS: The sensitivity and specificity of the PSMA PET/CT based miT-stage were 58% and 59% for pT3a-stage, 30% and 97% for ≥ pT3b-stage, and 68% and 61% for overall ≥ pT3-stage, respectively. No statistically significant differences in diagnostic accuracy were found between tracers. We found a substantial intra-observer agreement for PSMA PET/CT assessment of ≥ T3-stage (k 0.70) and ≥ T3b-stage (k 0.75), whereas the interobserver agreement for the assessment of ≥ T3-stage (k 0.47) and ≥ T3b-stage (k 0.41) were moderate. CONCLUSION: In a large, multicentre study evaluating 600 patients with newly diagnosed intermediate and high-risk PCa, we showed that PSMA PET/CT may have a value in local tumour staging when pathological tumour stage in the radical prostatectomy specimen was used as the reference standard. The intra-observer and interobserver variability of assessment of tumour extent on PSMA PET/CT was moderate to substantial.

Prostate-specific membrane antigen positron emission tomography in addition to multiparametric magnetic resonance imaging and biopsies to select prostate cancer patients for focal therapy.

OBJECTIVE: To evaluate the additional value of prostate-specific membrane antigen positron emission tomography (PSMA-PET) to conventional diagnostic tools to select patients for hemi-ablative focal therapy (FT). PATIENTS AND METHODS: We performed a retrospective analysis on a multicentre cohort (private and institutional) of 138 patients who underwent multiparametric magnetic resonance imaging (mpMRI), PSMA-PET, and systematic biopsies prior to radical prostatectomy between January 2011 and July 2021. Patients were eligible when they met the consensus criteria for FT: PSA <15 ng/mL, clinical/radiological T stage ≤T2b, and International Society of Urological Pathology (ISUP) grade 2-3. Clinically significant prostate cancer (csPCa) was defined as ISUP grade ≥2, extracapsular extension >0.5 mm or seminal vesicle involvement at final histopathology. The diagnostic accuracy of mpMRI, systematic biopsies and PSMA-PET for csPCa (separate and combined) was calculated within a four-quadrant prostate model by receiver-operating characteristic and 2 × 2 contingency analysis. Additionally, we assessed whether the diagnostic tools correctly identified patients suitable for hemi-ablative FT. RESULTS: In total 552 prostate quadrants were analysed and 272 (49%) contained csPCa on final histopathology. The area under the curve, sensitivity, specificity, positive predictive value and negative predictive value for csPCa were 0.79, 75%, 83%, 81% and 77%, respectively, for combined mpMRI and systematic biopsies, and improved after addition of PSMA-PET to 0.84, 87%, 80%, 81% and 86%, respectively (P < 0.001). On final histopathology 46/138 patients (33%) were not suitable for hemi-ablative FT. Addition of PSMA-PET correctly identified 26/46 (57%) non-suitable patients and resulted in 4/138 (3%) false-positive exclusions. CONCLUSIONS: Addition of PSMA-PET to the conventional work-up by mpMRI and systematic biopsies could improve selection for hemi-ablative FT and guide exclusion of patients for whom whole-gland treatments might be a more suitable treatment option.

99mTcPSMA-radioguided surgery in oligorecurrent prostate cancer: the randomised TRACE-II trial.

OBJECTIVE: To investigate whether combination treatment of prostate-specific membrane antigen (PSMA)-based radioguided surgery (RGS) with short-term androgen deprivation therapy (ADT) improves oncological outcomes in men with oligorecurrent prostate cancer (PCa) as compared to treatment with short-term ADT only. METHODS: The TRACE-II study is an investigator-initiated, prospective, randomised controlled clinical trial. Patients (aged >18 years) with hormone-sensitive recurrent PCa after radical prostatectomy or radiotherapy (brachytherapy or external beam radiotherapy), with involvement of ≤2 lymph nodes or local oligorecurrent disease within the pelvis as determined by PSMA positron emission tomography (PET)/computed tomography (CT) are randomly assigned in a 1:1 ratio between 6-month ADT (Arm A) or 6-month ADT plus RGS (Arm B). The primary objective is to determine clinical progression-free survival (CPFS) at 24 months. After PSMA-RGS, CPFS is defined as the time between the start of treatment and the appearance of a re-recurrence (any N1 or M1) as suggested by PSMA-PET/CT or symptoms related to progressive PCa, or death from any cause. The secondary objectives include metastasis-free survival at 2, 5 and 10 years, biochemical progression-free survival at 2 years, and patient-reported quality of life at 2, 5 and 10 years. A total of 60 patients, 30 per arm, will be included. The trial is powered (80%) to detect at least a 30% absolute difference in CPFS between the two study arms in the period 2 years after randomisation. We expect to enrol the required participants in 3 years. The study has an expected duration of 5 years in total. CONCLUSIONS: Combining RGS with short-term ADT might be oncologically beneficial for patients with oligorecurrent PCa. In this first randomised controlled trial, we are investigating the potential oncological benefits of this combined treatment, while also focusing on maintaining quality of life.

Targeting aberrant dendritic integration to treat cognitive comorbidities of epilepsy.

Memory deficits are a debilitating symptom of epilepsy, but little is known about mechanisms underlying cognitive deficits. Here, we describe a Na+ channel-dependent mechanism underlying altered hippocampal dendritic integration, degraded place coding and deficits in spatial memory. Two-photon glutamate uncaging experiments revealed a marked increase in the fraction of hippocampal first-order CA1 pyramidal cell dendrites capable of generating dendritic spikes in the kainate model of chronic epilepsy. Moreover, in epileptic mice dendritic spikes were generated with lower input synchrony, and with a lower threshold. The Nav1.3/1.1 selective Na+ channel blocker ICA-121431 reversed dendritic hyperexcitability in epileptic mice, while the Nav1.2/1.6 preferring anticonvulsant S-Lic did not. We used in vivo two-photon imaging to determine if aberrant dendritic excitability is associated with altered place-related firing of CA1 neurons. We show that ICA-121431 improves degraded hippocampal spatial representations in epileptic mice. Finally, behavioural experiments show that reversing aberrant dendritic excitability with ICA-121431 reverses hippocampal memory deficits. Thus, a dendritic channelopathy may underlie cognitive deficits in epilepsy and targeting it pharmacologically may constitute a new avenue to enhance cognition.

Rapid generation of massive thermodynamic datasets using frequency comb spectroscopy.

We demonstrate massively parallel spectroscopic measurements of 12C2H2 using an optical frequency comb. This allows for the rapid and simultaneous estimation of self-broadening and self-shifting of more than 50 optical transitions between 1512 and 1538 nm. The use of a temperature-controlled sealed gas cell allows us to measure both pressure- and temperature-mediated broadening and shifting. We present the results for the pressure-mediated self-broadening and self-shifting coefficients for 59 optical lines that make up the v1 + v3 combination band and a selection of hot bands. Our ability to measure the broadening of numerous transitions allows for the confirmation of prior work that shows that there is no measurable vibrational dependence across all acetylene bands, despite the strong dependence of the broadening coefficient on the rotational number. We also present an extensive measurement of the temperature dependence of the self-broadening for each of these 59 lines. This work shows the revolutionary power afforded by the frequency combs for rapid generation of large datasets related to thermodynamic variations of the key spectroscopic parameters of important gases.

Innovation for infection prevention and control-revisiting Pasteur's vision.

Louis Pasteur has long been heralded as one of the fathers of microbiology and immunology. Less known is Pasteur's vision on infection prevention and control (IPC) that drove current infection control, public health, and much of modern medicine and surgery. In this Review, we revisited Pasteur's pioneering works to assess progress and challenges in the process and technological innovation of IPC. We focused on Pasteur's far-sighted conceptualisation of the hospital as a reservoir of microorganisms and amplifier of transmission, aseptic technique in surgery, public health education, interdisciplinary working, and the protection of health services and patients. Examples from across the globe help inform future thinking for IPC innovation, adoption, scale up and sustained use.

Free-induction-decay magnetic field imaging with a microfabricated Cs vapor cell.

Magnetic field imaging is a valuable resource for signal source localization and characterization. This work reports an optically pumped magnetometer (OPM) based on the free-induction-decay (FID) protocol, that implements microfabricated cesium (Cs) vapor cell technology to visualize the magnetic field distributions resulting from various magnetic sources placed close to the cell. The slow diffusion of Cs atoms in the presence of a nitrogen (N2) buffer gas enables spatially independent measurements to be made within the same vapor cell by translating a 175 µm diameter probe beam over the sensing area. For example, the OPM was used to record temporal and spatial information to reconstruct magnetic field distributions in one and two dimensions. The optimal magnetometer sensitivity was estimated to be 0.43 pT/H z within a Nyquist limited bandwidth of 500 Hz. Furthermore, the sensor's dynamic range exceeds the Earth's field of approximately 50 µT, which provides a framework for magnetic field imaging in unshielded environments.

Context-drug-associations and reinstatement of drug-seeking behavior in male rats: Adolescent and adult time-dependent effects.

RATIONALE: Drug use during adolescence results in a life-long risk to develop substance-use disorders. Adolescent rats are sensitive to different drug-associated cues, compared to adults; however, the contribution of adolescent-formed context-drug-associations to elicit relapse-like behavior is underexplored. OBJECTIVES: The present study compared the effect of adolescent vs adult-formed context-drug associations to elicit time-dependent increases in cocaine-seeking behavior. This objective was accomplished using an abbreviated (ABRV) operant cocaine self-administration (Coc-SA), Extinction (EXT) paradigm, with cocaine-seeking tests occurring 1 day after training (T1, early relapse) or following 15 days of abstinence (T15, late relapse). METHODS: Adolescent and adult rats received ABRV Coc-SA in a distinct context (2 hr, 2x/day over 5 days) then EXT in a second context (2 hr, 2x/day over 4 days). Adolescent or adult cocaine-exposed rats were then tested (2 hr, non-rewarded) in either the previous EXT or Coc-paired contexts during early or late relapse. RESULTS & CONCLUSIONS: As previously reported, both adolescent and adult cocaine-exposed rats displayed similar magnitudes of cocaine intake and lever presses during Coc-SA, EXT, and early relapse. Independent analysis of adolescent and adult groups revealed differences in lever responding, specifically rats with cocaine exposure during adolescence showed time-dependent increases in lever responding during late relapse. These data suggest that cocaine-context associations formed during adolescence can elicit craving during adulthood and that these age-specific differences in contextual sensitivity may not be immediately observed at early relapse periods.

Microresonator-based spectral translation of a gain-switched semiconductor laser comb.

Gain-switched semiconductor laser technology provides a simple and low-cost method to generate optical frequency combs. However, the spectral coverage of these compact comb sources has been limited to the near-infrared range. Here, we combine a gain-switched laser comb with a continuous-wave translation laser within a periodically poled lithium niobate microresonator and demonstrate efficient and broadband sum-frequency conversion, spectrally translating the near-infrared comb to the visible domain. The broadband nature of the nonlinear conversion arises from a chirping of the domain inversion grating period along the microresonator circumference. We also validate the coherence of the visible-wavelength comb teeth which underlines the general applicability of this spectral translation approach.

Separate But Not Equal? A Cross-Sectional Study of Segregation by Payor Mix in Academic Primary Care Clinics.

BACKGROUND: At some US Academic Health Centers (AHCs), patients with predominantly Medicaid insurance are seen in one clinic and patients with other insurance are seen in another. The extent of this practice and implications are unknown. OBJECTIVE: To estimate the proportion of AHCs that have at least two primary care internal medicine clinics that differ substantially in proportion of patients with Medicaid and to compare patient demographic, staffing, and operational features. PARTICIPANTS: General internal medicine chiefs and clinic directors at 40 randomly selected US AHCs plus the top 10 AHCs in terms of NIH funding. MAIN MEASURE: An AHC was classified as maintaining clinics that differed substantially in the proportion of patients with Medicaid if any two differed by ≥ 40% (absolute). Other criteria were used for pre-specified secondary analyses (e.g., ≥ 30%). KEY RESULTS: Thirty-nine of 50 AHCs (78%) participated. Four of 39 (10%; 95% CI, 3 to 24%) had two clinics differing by ≥ 40% in the proportion of patients with Medicaid, eight (21%; 95% CI, 9 to 36%) had clinics differing by ≥ 30%, and 15 (38%; 95% CI, 23 to 55%) had clinics differing by ≥ 20%. Clinics with more patients with Medicaid by any of the three criteria were more likely to employ resident physicians as providers of longitudinal care (with faculty supervision) and more likely to have patients who were Black or Hispanic. CONCLUSIONS: Some US AHCs maintain separate clinics defined by the proportion of patients with Medicaid. Clinics with a higher proportion of patients insured by Medicaid are more likely to employ residents (with faculty oversight), feature residents as providers of longitudinal care, and serve patients who are Black and Hispanic. Further research is needed to understand why some AHCs have primary care clinics distinguishable by insurance mix with the goal of ensuring that racism and discrimination are not root causes.

Within-population variation in body size plasticity in response to combined nutritional and thermal stress is partially independent from variation in development time.

Ongoing climate change has forced animals to face changing thermal and nutritional environments. Animals can adjust to such combinations of stressors via plasticity. Body size is a key trait influencing organismal fitness, and plasticity in this trait in response to nutritional and thermal conditions varies among genetically diverse, locally adapted populations. The standing genetic variation within a population can also influence the extent of body size plasticity. We generated near-isogenic lines from a newly collected population of Drosophila melanogaster at the mid-point of east coast Australia and assayed body size for all lines in combinations of thermal and nutritional stress. We found that isogenic lines showed distinct underlying patterns of body size plasticity in response to temperature and nutrition that were often different from the overall population response. We then tested whether plasticity in development time could explain, and therefore regulate, variation in body size to these combinations of environmental conditions. We selected five genotypes that showed the greatest variation in response to combined thermal and nutritional stress and assessed the correlation between response of developmental time and body size. While we found significant genetic variation in development time plasticity, it was a poor predictor of body size among genotypes. Our results therefore suggest that multiple developmental pathways could generate genetic variation in body size plasticity. Our study emphasizes the need to better understand genetic variation in plasticity within a population, which will help determine the potential for populations to adapt to ongoing environmental change.

The prognostic value of lymph node staging with prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) and extended pelvic lymph node dissection in node-positive patients with prostate cancer.

OBJECTIVES: To investigate whether patients with suspected pelvic lymph node metastases (molecular imaging [mi] N1) on staging prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) had a different oncological outcome compared to those in whom the PSMA PET/CT did not reveal any pelvic lymph node metastases (miN0). PATIENTS AND METHODS: All patients with pelvic lymph node metastatic (pN1) disease after robot-assisted radical prostatectomy (RARP) and extended pelvic lymph node dissection (ePLND) between January 2017 and December 2020 were included. To assess predictors of biochemical progression of disease after RARP, a multivariable Cox regression analysis was performed, including number of tumour-positive lymph nodes, diameter of the largest nodal metastasis, and extranodal extension. RESULTS: In total, 145 patients were diagnosed with pN1 disease after ePLND. The median biochemical progression-free survival in patients with miN0 on PSMA PET/CT was 13.7 months, compared to 7.9 months in patients with miN1 disease (P = 0.006). On multivariable Cox regression analysis, both number of tumour-positive lymph nodes (>2 vs 1-2: hazard ratio [HR] 1.97; P = 0.005) and diameter of the largest nodal metastasis (HR 1.12; P < 0.001) were significant independent predictors of biochemical progression of disease. CONCLUSION: Patients in whom pelvic lymph node metastases were suspected on preoperative PSMA imaging (miN1), patients diagnosed with >2 tumour-positive lymph nodes, and patients with a larger diameter of the largest nodal metastasis had a significantly increased risk of biochemical disease progression after surgery.

Staging fluorodeoxyglucose positron emission tomography/computed tomography for muscle-invasive bladder cancer: a nationwide population-based study.

OBJECTIVE: To provide insight into the use and staging information on lymph-node involvement added by fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) in patients with muscle-invasive bladder cancer (MIBC), based on a nationwide population-based cohort study. PATIENTS AND METHODS: We analysed a nationwide cohort of patients with MIBC without signs of distant metastases, newly diagnosed in the Netherlands between November 2017 and October 2019. From this cohort, we selected patients who underwent pre-treatment staging with CT only or CT and FDG-PET/CT. The distribution of patients, disease characteristics, imaging findings, nodal status (clinical nodal stage cN0 vs cN+) and treatment were described for each imaging modality group (CT only vs CT and FDG-PET/CT). RESULTS: We identified 2731 patients with MIBC: 1888 (69.1%) underwent CT only; 606 (22.2%) underwent CT and FDG-PET/CT, 237 (8.6%) underwent no CT. Of the patients who underwent CT only, 200/1888 (10.6%) were staged as cN+, vs 217/606 (35.8%) who underwent CT and FDG-PET/CT. Stratified analysis showed that this difference was found in patients with clinical tumour stage (cT)2 as well as cT3/4 MIBC. Of patients who underwent both imaging modalities and were staged with CT as cN0, 109/498 (21.9%) were upstaged to cN+ based on FDG-PET/CT. Radical cystectomy (RC) was the most common treatment within both imaging groups. Preoperative chemotherapy was more frequently applied in cN+ disease and in FDG-PET/CT-staged patients. Concordance of pathological N stage after upfront RC was higher among patients staged as cN+ with CT and FDG-PET/CT (50.0% pN+) than those staged as cN+ with only CT (39.3%). CONCLUSION: Patients with MIBC who underwent pre-treatment staging with FDG-PET/CT were more often staged as lymph node positive, regardless of cT stage. In patients with MIBC who underwent CT and FDG-PET/CT, FDG-PET/CT led to clinical nodal upstaging in approximately one-fifth. Additional imaging findings may influence subsequent treatment strategies.

Using prostate-specific membrane antigen positron-emission tomography to guide prostate biopsies and stage men at high-risk of prostate cancer.

OBJECTIVE: To assess whether a diagnostic pathway in which prostate-specific membrane antigen (PSMA) positron-emission tomography (PET)/computed tomography (CT) is used as a single imaging modality is feasible to guide targeted biopsy and to detect clinically significant prostate cancer (csPCa) in biopsy-naïve men at high-risk of disease. PATIENTS AND METHODS: A total of 60 men with a prostate-specific antigen (PSA) level of 20-50 ng/mL underwent 18 F-PSMA(DCFPyL)-PET/CT prior to prostate biopsies in this prospective, non-randomised cohort study. Magnetic resonance imaging (MRI) was not performed. Using a 12-segment mapping model of the prostate, PSMA-guided targeted biopsy was performed along with systematic biopsies. The detection rate of PCa and csPCa was assessed for combined systematic and targeted biopsy, and for targeted biopsy only. csPCa was defined as a prostate biopsy with an International Society of Uropathology (ISUP) Grade Group ≥2. RESULTS: Lesions suspicious for PCa in the prostate gland were observed on all PSMA-PET/CTs. A total of 27/60 men (45%) already had metastatic disease on staging 18 F-PSMA(DCFPyL)-PET/CT. Combined PSMA-guided targeted and systematic biopsies detected PCa in 56/60 (93.3%) patients, with 52 of them (92.9%) having csPCa. PSMA-guided targeted biopsy, if performed as a single biopsy modality, identified PCa in 52/60 men (86.7%) and in 27/27 men (100%) men with metastases. CONCLUSIONS: Using the PSMA-driven single imaging modality pathway in biopsy-naïve men at high-risk of PCa, a substantial number of diagnostic MRI scans could be avoided while at the same time obtaining adequate targeting, staging, and detection of csPCa.

Performance of a deep convolutional neural network for MRI-based vertebral body measurements and insufficiency fracture detection.

OBJECTIVES: The aim is to validate the performance of a deep convolutional neural network (DCNN) for vertebral body measurements and insufficiency fracture detection on lumbar spine MRI. METHODS: This retrospective analysis included 1000 vertebral bodies in 200 patients (age 75.2 ± 9.8 years) who underwent lumbar spine MRI at multiple institutions. 160/200 patients had ≥ one vertebral body insufficiency fracture, 40/200 had no fracture. The performance of the DCNN and that of two fellowship-trained musculoskeletal radiologists in vertebral body measurements (anterior/posterior height, extent of endplate concavity, vertebral angle) and evaluation for insufficiency fractures were compared. Statistics included (a) interobserver reliability metrics using intraclass correlation coefficient (ICC), kappa statistics, and Bland-Altman analysis, and (b) diagnostic performance metrics (sensitivity, specificity, accuracy). A statistically significant difference was accepted if the 95% confidence intervals did not overlap. RESULTS: The inter-reader agreement between radiologists and the DCNN was excellent for vertebral body measurements, with ICC values of > 0.94 for anterior and posterior vertebral height and vertebral angle, and good to excellent for superior and inferior endplate concavity with ICC values of 0.79-0.85. The performance of the DCNN in fracture detection yielded a sensitivity of 0.941 (0.903-0.968), specificity of 0.969 (0.954-0.980), and accuracy of 0.962 (0.948-0.973). The diagnostic performance of the DCNN was independent of the radiological institution (accuracy 0.964 vs. 0.960), type of MRI scanner (accuracy 0.957 vs. 0.964), and magnetic field strength (accuracy 0.966 vs. 0.957). CONCLUSIONS: A DCNN can achieve high diagnostic performance in vertebral body measurements and insufficiency fracture detection on heterogeneous lumbar spine MRI. KEY POINTS: • A DCNN has the potential for high diagnostic performance in measuring vertebral bodies and detecting insufficiency fractures of the lumbar spine.

A standardized method to measure the membranous urethral length (MUL) on MRI of the prostate with high inter- and intra-observer agreement.

OBJECTIVES: The membranous urethral length (MUL), defined as the length between the apex and penile base as measured on preoperative prostate magnetic resonance imaging (MRI), is an important predictor for urinary incontinence after radical prostatectomy. Literature on inter- and intra - observer agreement of MUL measurement is limited. We studied the inter- and intra-observer agreement between radiologists using a well-defined method to measure the MUL on the prostate MRI. METHODS: Prostate cancer patients underwent a preoperative MRI and robot-assisted radical prostatectomy (RARP) at one high-volume RARP center. MUL measurement was based on well-defined landmarks on sagittal T2-weighted (anatomical) images. Three radiologists independently performed MUL measurements retrospectively in 106 patients blinded to themselves, to each other, and to clinical outcomes. The inter- and intra-observer agreement of MUL measurement between the radiologists were calculated, expressed as intra-class correlation coefficient (ICC). RESULTS: The initial inter-observer agreement was ICC 0.63; 95% confidence interval (CI) 0.28-0.81. Radiologist 3 measured the MUL mean 3.9 mm (SD 3.3) longer than the other readers, interpreting the caudal point of the MUL (penile base) differently. After discussion on the correct anatomical definition, radiologist 3 re-assessed all scans, which resulted in a high inter-observer agreement (ICC 0.84; 95% CI 0.66-0.91). After a subsequent reading by radiologists 1 and 2, the intra-observer agreements were ICC 0.93; 95% CI 0.89-0.96, and ICC 0.98; 95% CI 0.97-0.98, respectively. Limitation is the monocenter design. CONCLUSIONS: The MUL can be measured reliably with high agreement among radiologists. KEY POINTS: • After discussion on the correct anatomical definition, the inter- and intra - observer agreements of membranous urethral length (MUL) measurement on magnetic resonance imaging (MRI) were high. • A reproducible method to measure the MUL can improve the clinical usefulness of prediction models for urinary continence after RARP which may benefit patient counselling.