Category: Statistics

Eur J Nucl Med Mol Imaging. 2023 Apr 10. doi: 10.1007/s00259-023-06191-7. Online ahead of print.

ABSTRACT

OBJECTIVE: To determine the diagnostic accuracy of the hybrid tracer indocyanine green (ICG)-Technetium-99 m(^99mTc)-nanocolloid compared to sequential tracers of ^99mTc-nanocolloid and free-ICG in detecting tumor-positive lymph nodes (LN) during primary surgery in prostate cancer (PCa) patients.

INTRODUCTION: Image-guided surgery strategies can help visualize individual lymphatic drainage patterns and sentinel lymph nodes (SLNs) in PCa patients. For lymphatic mapping radioactive, fluorescent and hybrid tracers are being clinically exploited. In this prospective randomized phase II trial, we made a head-to-head comparison between ICG-^99mTc-nanocolloid (hybrid group) and ^99mTc-nanocolloid and subsequent free-ICG injection (sequential group).

METHODS: PCa patients with a >5% risk of lymphatic involvement according to the 2012 Briganti nomogram and planned for prostatectomy were included and randomized (1:1) between ultrasound-guided intraprostatic tracer administration of ICG-^99mTc-nanocolloid (n = 69) or ^99mTc-nanocolloid (n = 69) 5 h before surgery. Preoperative lymphoscintigraphy and SPECT/CT were performed to define the locations of the SLNs. Additionally, all participants in the sequential group received an injection of free-ICG at time of surgery. Subsequently, all (S)LNs were dissected using fluorescence guidance followed by an extended pelvic lymph node dissection (ePLND). The primary outcome was the total number of surgically removed (S)LNs and tumor-positive (S)LNs.

RESULTS: The total number of surgically removed (S)LN packages was 701 and 733 in the hybrid and sequential groups, respectively (p = 0.727). The total number of fluorescent LNs retrieved was 310 and 665 nodes in the hybrid and sequential groups, respectively (p < 0.001). However, no statistically significant difference was observed in the corresponding number of tumor-positive nodes among the groups (44 vs. 33; p = 0.470). Consequently, the rate of tumor-positive fluorescent LNs was higher in the hybrid group (7.4%) compared to the sequential group (2.6%; p = 0.002), indicating an enhanced positive predictive value for the hybrid approach. There was no difference in complications within 90 days after surgery (p = 0.78).

CONCLUSIONS: The hybrid tracer ICG-^99mTc-nanocolloid improved the positive predictive value for tumor-bearing LNs while minimizing the number of fluorescent nodes compared to the sequential tracer approach. Consequently, the hybrid tracer ICG-^99mTc-nanocolloid enables the most reliable and minimal invasive method for LN staging in PCa patients.

PMID:37036490 | DOI:10.1007/s00259-023-06191-7

Abdom Radiol (NY). 2023 Apr 10. doi: 10.1007/s00261-023-03894-1. Online ahead of print.

ABSTRACT

PURPOSE: To investigate the effects of various prostate biopsy protocols with reduced cores on the detection of clinically significant prostate cancer (csPCa) in individuals with MRI-visible lesions (Prostate Imaging Reporting and Data System ≥ 3).

METHODS: A total of 464 patients with MRI-visible lesions were recruited. All patients underwent two or more targeted biopsies (TB) and systematic biopsies (SB). Several hypothetical biopsy schemes were set-up: TB alone, TB+ipsilateral SB, TB+contralateral SB, TB+SB of the targeted sector (TB+t-SB), and TB+SB of the non-targeted sector (TB+n-SB). A subgroup analysis of patients with multiple MRI-visible lesions was performed. The standard of reference was defined as TB+SB. McNemar test was used to compare csPCa detection rates between various sampling schemes.

RESULTS: The detection rates for prostate cancer and csPCa were 72.8% (338 of 464) and 62.1% (288 of 464), respectively. There were 8.0%, 0.3%, 6.3%, 1.0%, and 4.5% cases in which TB alone, TB+ipsilateral SB, TB+contralateral SB, TB+t-SB, and TB+n-SB would have missed csPCa, respectively. All hypothetical schemes, with the exception of TB+contralateral SB (p = 0.063), significantly outperformed TB alone in terms of csPCa detection (p < 0.05). As for the multi-focus cohort, which included 48 cases, none of the non-index lesions had a higher Gleason grade than the index lesions within the same patients.

CONCLUSION: TB+ipsilateral SB might be the optimal biopsy scheme for detecting csPCa. As for the multi-focus cohort, the biopsy of the non-index lesions provided limited pathological information.

PMID:37036488 | DOI:10.1007/s00261-023-03894-1

Eur Radiol. 2023 Apr 10. doi: 10.1007/s00330-023-09553-9. Online ahead of print.

ABSTRACT

OBJECTIVES: To evaluate the correlation between histogram parameters derived from synthetic magnetic resonance imaging (SyMRI) and prognostically relevant factors in nasopharyngeal carcinoma (NPC).

METHODS: Fifty-nine consecutive NPC patients were prospectively enrolled. Quantitative parameters (T1, T2, and proton density (PD)) were obtained by outlining the three-dimensional volume of interest (VOI) of all lesions. Then, histogram analysis of these quantitative parameters was performed and the correlations with prognostically relevant factors were assessed. By choosing appropriate cutoff, we divided the sample into two groups. Independent-samples t test/Mann-Whitney U test was used and ROC curve analysis was further processed.

RESULTS: Histogram parameters of the T1, T2, and PD maps were positively correlated with the Ki-67 expression levels, and PD_mean was the most representative parameter (AUC: 0.861). The PD map exhibited good performance in differentiating epidermal growth factor receptor (EGFR) expression levels (AUC: 0.706~0.732) and histological type (AUC: 0.650~0.660). T2_minimum was highest correlated with Epstein-Barr virus (EBV) DNA levels (r = – 0.419), and PD_75th percentile exhibited the highest performance in distinguishing positive and negative EBV DNA groups (AUC: 0.721). T1_minimum was statistically correlated with EA-IgA expression (r = – 0.313). Additionally, several histogram parameters were negatively correlated with tumor stage (T stage: r = – 0.259 ~ – 0.301; N stage: r = – 0.348 ~ – 0.456; clinical stage: r = – 0.419).

CONCLUSIONS: Histogram parameters of SyMRI could reflect tissue intrinsic characteristics and showed potential value in assessing the Ki-67 and EGFR expression levels, histological type, EBV DNA level, EA-IgA, and tumor stage.

KEY POINTS: • SyMRI combined with histogram analysis may help clinicians to assess different prognostic factor statuses in nasopharyngeal carcinoma. • The PD map exhibited good discriminating performance in the Ki-67 and EGFR expression levels. • Histogram parameters of SyMRI were negatively correlated with EBV-related blood biomarkers and TNM stage.

PMID:37036478 | DOI:10.1007/s00330-023-09553-9

Biom J. 2023 Apr 10:e2200016. doi: 10.1002/bimj.202200016. Online ahead of print.

ABSTRACT

We propose a hidden Markov model for multivariate continuous longitudinal responses with covariates that accounts for three different types of missing pattern: (I) partially missing outcomes at a given time occasion, (II) completely missing outcomes at a given time occasion (intermittent pattern), and (III) dropout before the end of the period of observation (monotone pattern). The missing-at-random (MAR) assumption is formulated to deal with the first two types of missingness, while to account for the informative dropout, we rely on an extra absorbing state. Estimation of the model parameters is based on the maximum likelihood method that is implemented by an expectation-maximization (EM) algorithm relying on suitable recursions. The proposal is illustrated by a Monte Carlo simulation study and an application based on historical data on primary biliary cholangitis.

PMID:37035989 | DOI:10.1002/bimj.202200016

Clin Neuropsychol. 2023 Apr 10:1-20. doi: 10.1080/13854046.2023.2196441. Online ahead of print.

ABSTRACT

Objective: This study examined the relationship between cognitive reserve measured with the Cognitive Reserve Index questionnaire (CRIq) and cognitive and functional outcomes in a chronic traumatic brain injury (TBI) cohort compared to a non-TBI cohort. The utility of the CRIq was compared to common proxies of cognitive reserve (premorbid IQ and years of education) in TBI and non-TBI cohorts. Method: Participants were 105 individuals with moderate-severe TBI (10-33 years post injury) and 91 participants without TBI. Cognitive outcome was examined across four cognitive factors; verbal memory, visual ability and memory, executive attention, and episodic memory. Functional outcome was measured using the Glasgow Outcome Scale Extended. The CRIq total score and three subscale scores (education, work, leisure) were examined. Results: In the TBI cohort, associations were identified between two CRIq subscales and cognitive factors (CRIq education and verbal memory; CRIq work and executive attention). There were no associations between CRIq leisure and cognitive outcomes, or between CRIq and functional outcome. Model selection statistics suggested premorbid IQ and years of education provided a better fit than the CRIq for the relationship between cognitive reserve with two cognitive factors and functional outcome, with neither model providing an improved fit for the remaining two cognitive factors. This finding was broadly consistent in the non-TBI cohort. Conclusion: Cognitive reserve contributes significantly to long-term clinical outcomes following moderate-severe TBI. The relationship between cognitive reserve and long-term cognitive and functional outcomes following TBI is best characterised with traditional proxies of cognitive reserve, mainly premorbid IQ, rather than the CRIq.

PMID:37035985 | DOI:10.1080/13854046.2023.2196441

Int J Tuberc Lung Dis. 2023 Apr 1;27(4):332-334. doi: 10.5588/ijtld.22.0417.

NO ABSTRACT

PMID:37035968 | DOI:10.5588/ijtld.22.0417

Biom J. 2023 Apr 10:e2200122. doi: 10.1002/bimj.202200122. Online ahead of print.

ABSTRACT

Causal inference is widely used in various fields, such as biology, psychology, and economics, etc. In observational studies, balancing the covariates is an important step in estimating the causal effect. This study extends the one-dimensional entropy balancing method to multiple dimensions to balance the covariates. Both parametric and nonparametric methods are proposed to estimate the causal effect of multivariate continuous treatments and theoretical properties of the two estimations are provided. Furthermore, the simulation results show that the proposed method is better than other methods in various cases. Finally, the proposed method is applied to analyze the impact of the duration and frequency of smoking on medical expenditure. The results from the parametric method indicate that the frequency of smoking increases medical expenditure while the duration of smoking does not. The results from the nonparametric method indicate that there is a short-term downward trend and then a long-term upward trend as the duration and frequency of smoking increase.

PMID:37035966 | DOI:10.1002/bimj.202200122

Diabet Med. 2023 Apr 10:e15111. doi: 10.1111/dme.15111. Online ahead of print.

ABSTRACT

OBJECTIVES: To investigate whether manganese-enhanced magnetic resonance imaging can assess functional pancreatic beta-cell mass in people with type 1 diabetes mellitus.

METHODS: In a prospective case-control study, 20 people with type 1 diabetes mellitus (10 with low (≥50 pmol/L) and 10 with very low (<50 pmol/L) C-peptide concentrations) and 15 healthy volunteers underwent manganese-enhanced magnetic resonance imaging of the pancreas following an oral glucose load. Scan-rescan reproducibility was performed in 10 participants.

RESULTS: Mean pancreatic manganese uptake was 31±6 mL/100 g of tissue/min in healthy volunteers (median 32 [interquartile range 23-36] years, 6 women), falling to 23±4 and 13±5 mL/100 g of tissue/min (p≤0.002 for both) in people with type1 diabetes mellitus (52 [44-61] years, 6 women) and low or very low plasma C-peptide concentrations respectively. Pancreatic manganese uptake correlated strongly with plasma C-peptide concentrations in people with type1 diabetes mellitus (r=0.73, p<0.001) but not in healthy volunteers (r=-0.054, p=0.880). There were no statistically significant correlations between manganese uptake and age, body-mass index, or glycated haemoglobin. There was strong intra-observer (mean difference: 0.31 (limits of agreement -1.42 to 2.05) mL/100 g of tissue/min; intra-class correlation, ICC=0.99), inter-observer (-1.23 (-5.74 to 3.27) mL/100 g of tissue/min; ICC=0.85) and scan-rescan (-0.72 (-2.9 to 1.6) mL/100 g of tissue/min; ICC=0.96) agreement for pancreatic manganese uptake.

CONCLUSIONS: Manganese-enhanced magnetic resonance imaging provides a potential reproducible non-invasive measure of functional beta-cell mass in people with type 1 diabetes mellitus. This holds major promise for the investigating type 1 diabetes, monitoring disease progression and assessing novel immunomodulatory interventions.

PMID:37035965 | DOI:10.1111/dme.15111

Biom J. 2023 Apr 10:e2200135. doi: 10.1002/bimj.202200135. Online ahead of print.

ABSTRACT

Cluster-randomized trials (CRTs) involve randomizing entire groups of participants-called clusters-to treatment arms but are often comprised of a limited or fixed number of available clusters. While covariate adjustment can account for chance imbalances between treatment arms and increase statistical efficiency in individually randomized trials, analytical methods for individual-level covariate adjustment in small CRTs have received little attention to date. In this paper, we systematically investigate, through extensive simulations, the operating characteristics of propensity score weighting and multivariable regression as two individual-level covariate adjustment strategies for estimating the participant-average causal effect in small CRTs with a rare binary outcome and identify scenarios where each adjustment strategy has a relative efficiency advantage over the other to make practical recommendations. We also examine the finite-sample performance of the bias-corrected sandwich variance estimators associated with propensity score weighting and multivariable regression for quantifying the uncertainty in estimating the participant-average treatment effect. To illustrate the methods for individual-level covariate adjustment, we reanalyze a recent CRT testing a sedation protocol in 31 pediatric intensive care units.

PMID:37035941 | DOI:10.1002/bimj.202200135

Ethn Health. 2023 Apr 9:1-12. doi: 10.1080/13557858.2023.2198684. Online ahead of print.

ABSTRACT

OBJECTIVE: Osteoarthritis (OA) is a prominent musculoskeletal disorder that affects approximately 303 million people worldwide. The challenges that language barriers present to the Latina population in regard to the diagnosis and treatment of OA remain largely unknown. The objective of this study was to examine disparities in the diagnosis and treatment of arthritic conditions in English- and Spanish-speaking Latinas over 40 years of age.

DESIGN: We analyzed data from the CDC’s Behavioral Risk Screening and Surveillance System (BRFSS), combining the 2017-2020 cycles using sampling weights provided by BRFSS, adjusted for multiple cycles. Determination of English- or Spanish-speaking groups was based on the language of the survey submitted. We calculated population estimates for arthritis diagnosis, physical limitations, and mean joint pain among language groups and by age (40-64 and 65+) and determined associations via odds ratios.

RESULTS: Rates of arthritis diagnosis between groups were similar; however we found that Spanish-speaking Latinas 65+ were statistically more likely to report being limited by pain (AOR: 1.55; 95% CI: 1.14-2.09), and among both age groups Spanish-speaking Latinas reported higher pain scores than the English-speaking group (40-64 age group: Coef: 0.74, SE = 0.14, P < .001; 65 + age group: Coef: 1.05, SE = 0.2, P < .001).

CONCLUSION: Results from this study show that while there were no significant differences in rates of diagnosis, Spanish-speaking Latinas were more likely to be limited by joint pain and report higher pain scores.

PMID:37032428 | DOI:10.1080/13557858.2023.2198684