The relationship between changes in pain intensity and functional disability in persistent disabling low back pain during a course of cognitive functional therapy.

OBJECTIVES: Pain relief and reduced disability are both common treatment targets for persistent disabling low back pain (LBP). Cross-sectional studies show a moderate relationship between functional disability and pain intensity, but little is known about the relationship between changes in pain intensity and functional disability over multiple time points. The objective of this study was to investigate the associations between changes in functional disability and pain intensity and whether changes occurred simultaneously or differentially during a course of cognitive functional therapy for people with persistent disabling LBP. METHODS: Self-reported measures of pain intensity and patient-specific functional disability were collected prior to each treatment session from 40 participants during a 12-week intervention period. Linear mixed modeling was used to assess simultaneous and lagged associations between pain intensity and functional disability over time. Sensitivity analysis using nonparametric subject-specific methods (simulation modeling analysis) was also performed. RESULTS: Thirty-five participants had sufficient data for analysis. Using the linear mixed-model approach, there was evidence of a moderate and simultaneous association between pain intensity and functional disability over time (regression coefficient = 0.56, 95% confidence interval: 0.44-0.68, p < 0.001). Simulation modeling analysis supported weak to mostly strong associations and supported for simultaneous change in pain and disability for the majority of participants (22 of 35, 64%). CONCLUSION: Changes in pain intensity and functional disability were moderately related across the intervention. Visual inspection of graphs indicated a very close relationship in some individuals and a decoupling of pain intensity and functional disability in others. The changes in pain intensity and functional disability seem to occur simultaneously in most individuals.

A Prospective Qualitative Inquiry of Patient Experiences of Cognitive Functional Therapy for Chronic Low Back Pain During the RESTORE Trial.

Cognitive functional therapy (CFT) is a person-centered biopsychosocial physiotherapy intervention that has recently demonstrated large, durable effects in reducing pain and disability in people with chronic low back pain (CLBP). However, exploration of the treatment process from the patients' perspectives, including the process of gaining control and agency over CLBP, is relatively understudied in this patient population. This qualitative study explored the experiences of eight participants from the RESTORE trial through longitudinally following their experiences, including interviews during baseline, mid-treatment, end-treatment, and 12-month follow-up. Data were analyzed according to a narrative approach. Findings described the overarching narrative themes of "The Journey to Self-Management." Within this overarching narrative, four distinct narratives were identified, beginning with "Left High and Dry," capturing the experience of isolation and abandonment with CLBP before commencing CFT, and concluding with three narratives of the experience of CFT from the start of treatment through to the 12-month follow-up. These included "Plain, Smooth Sailing," describing a journey of relative ease and lack of obstacles; "Learning the Ropes and Gaining Sea Legs," capturing an iterative process of learning and negotiating setbacks; and "Sailing Through Headwinds," describing the experience of struggle to gain agency and control over CLBP through CFT. Clinicians treating individuals with CLBP can use these insights to more effectively facilitate self-management, and people living with CLBP may find resonance from the narrative themes to support their journeys.

Whole-Body Multiparametric PET in Clinical Oncology: Current Status, Challenges, and Opportunities.

The interpretation of clinical oncologic PET studies has historically used static reconstructions based on SUVs. SUVs and SUV-based images have important limitations, including dependence on uptake times and reduced conspicuity of tracer-avid lesions in organs with high background uptake. The acquisition of dynamic PET images enables additional PET reconstructions via Patlak modeling, which assumes that a tracer is irreversibly trapped by tissues of interest. The resulting multiparametric PET images capture a tracer's net trapping rate (Ki) and apparent volume of distribution (VD), separating the contributions of bound and free tracer fractions to the PET signal captured in the SUV. Potential benefits of multiparametric PET include higher quantitative stability, superior lesion conspicuity, and greater accuracy for differentiating malignant and benign lesions. However, the imaging protocols necessary for multiparametric PET are inherently more complex and time-intensive, despite the recent introduction of automated or semiautomated scanner-based reconstruction packages. In this Review, we examine the current state of multiparametric PET in whole-body oncologic imaging. We summarize the Patlak methodology and relevant tracer kinetics, discuss clinical workflows and protocol considerations, and highlight clinical challenges and opportunities. We aim to help oncologic imagers make informed decisions about whether to implement multiparametric PET in their clinical practices.

Patients with worse disability respond best to cognitive functional therapy for chronic low back pain: a pre-planned secondary analysis of a randomised trial.

QUESTION: Do five baseline moderators identify patients with chronic low back pain who respond best to cognitive functional therapy (CFT) when compared with usual care? DESIGN: Secondary analysis of the RESTORE randomised controlled trial. PARTICIPANTS: A total of 492 adults with low back pain for > 3 months with at least moderate pain-related activity limitation. INTERVENTION: Participants were allocated to CFT alone or CFT plus biofeedback; these two groups were combined for this secondary analysis. The control group was usual care. OUTCOME MEASURES: The outcome was activity limitation measured using the Roland Morris Disability Questionnaire (RMDQ) at 3, 6, 13, 26, 40 and 52 weeks. Investigated effect modifiers were baseline measures of activity limitation, cognitive flexibility, pain intensity, self-efficacy and catastrophising. RESULTS: Baseline levels of activity limitation and, potentially, cognitive flexibility were associated with different effects of CFT treatment, while pain intensity, self-efficacy and catastrophising were not. Patients who had higher baseline activity limitation had greater treatment effects at 13 and 52 weeks. A person with a baseline RMDQ score of 18 (90th percentile) would on average be 6.1 (95% CI 4.8 to 7.4) points better at 13 weeks if they received CFT compared with usual care. However, a person with a baseline score of 7 (10th percentile) would on average be 3.6 (95% CI 2.6 to 4.6) points better at 13 weeks. CONCLUSION: The finding that CFT is most effective among patients who are most disabled and incur the greatest burden strongly suggests that CFT should be considered as a treatment for this group of patients. REGISTRATION: ACTRN12618001396213.

Changes in 24(S)-Hydroxycholesterol Are Associated with Cognitive Performance in Early Huntington's Disease: Data from the TRACK and ENROLL HD Cohorts.

Background: There is evidence for dysregulated cholesterol homeostasis in Huntington's disease (HD). The brain-specific cholesterol metabolite 24(S)-hydroxycholesterol (24(S)-OHC) is decreased in manifest HD. 24(S)-OHC is an endogenous positive allosteric modulator (PAM) of the N-methyl-D-aspartate (NMDA) receptor, suggesting lower 24(S)-OHC may contribute to NMDA receptor hypofunction in HD. We hypothesized changes in 24(S)-OHC would be associated with cognitive impairment in early HD. Objective: To determine the interactions between oxysterols (24(S)-OHC, 25-OHC, and 27-OHC) at the NMDA receptor, the plasma levels of these oxysterols, and how these levels relate to cognitive performance. Methods: An in vitro competition assay was used to evaluate interactions at the NMDA receptor, liquid chromatography coupled tandem mass spectrometry (LC-MS/MS) was used to measure plasma 24(S)-OHC, 25-OHC, and 27-OHC levels, and correlation analyses investigated their relationship to performance on cognitive endpoints in TRACK and ENROLL-HD (NCT01574053). Results: In vitro, 25-OHC and 27-OHC attenuated the PAM activity of 24(S)-OHC on the NMDA receptor. Lower plasma 24(S)-OHC levels and 24(S)/25-OHC ratios were detected in participants with early HD. Moderate and consistent associations were detected between plasma 24(S)/25-OHC ratio and performance on Stroop color naming, symbol digit modality, Trails A/B, and emotion recognition. Little association was observed between the ratio and psychiatric or motor endpoints, suggesting specificity for the relationship to cognitive performance. Conclusions: Our findings support growing evidence for dysregulated CNS cholesterol homeostasis in HD, demonstrate a relationship between changes in oxysterols and cognitive performance in HD, and propose that NMDA receptor hypofunction may contribute to cognitive impairment in HD.

Quantitative Assessments of Tumor Activity in a General Oncologic PET/CT Population: Which Metric Minimizes Tracer Uptake Time Dependence?

In oncologic PET, the SUV and standardized uptake ratio (SUR) of a viable tumor generally increase during the postinjection period. In contrast, the net influx rate (Ki ), which is derived from dynamic PET data, should remain relatively constant. Uptake-time-corrected SUV (cSUV) and SUR (cSUR) have been proposed as uptake-time-independent, static alternatives to Ki Our primary aim was to quantify the intrascan repeatability of Ki , SUV, cSUV, SUR, and cSUR among malignant lesions on PET/CT. An exploratory aim was to assess the ability of cSUR to estimate Ki Methods: This prospective, single-center study enrolled adults undergoing standard-of-care oncologic PET/CT. SUV and Ki images were reconstructed from dynamic PET data obtained before (∼35-50 min after injection) and after (∼75-90 min after injection) standard-of-care imaging. Tumors were manually segmented. Quantitative metrics were extracted. cSUVs and cSURs were calculated for a 60-min postinjection reference uptake time. The magnitude of the intrascan test-retest percent change (test-retest |%Δ|) was calculated. Coefficients of determination (R 2) and intraclass correlation coefficients (ICC) were also computed. Differences between metrics were assessed via the Wilcoxon signed-rank test (α, 0.05). Results: This study enrolled 78 subjects; 41 subjects (mean age, 63.8 y; 24 men) with 116 lesions were analyzed. For both tracers, SUVmax and maximum SUR (SURmax) had large early-to-late increases (i.e., poor intrascan repeatability). Among [18F]FDG-avid lesions (n = 93), there were no differences in intrascan repeatability (median test-retest |%Δ|; ICC) between the maximum Ki (Ki ,max) (13%; 0.97) and either the maximum cSUV (cSUVmax) (12%, P = 0.90; 0.96) or the maximum cSUR (cSURmax) (13%, P = 0.67; 0.94). For DOTATATE-avid lesions (n = 23), there were no differences in intrascan repeatability between the Ki ,max (11%; 0.98) and either the cSUVmax (13%, P = 0.41; 0.98) or the cSURmax (11%, P = 0.08; 0.94). The SUVmax, cSUVmax, SURmax, and cSURmax were all strongly correlated with the Ki ,max for both [18F]FDG (R 2, 0.81-0.92) and DOTATATE (R 2, 0.88-0.96), but the cSURmax provided the best agreement with the Ki ,max across early-to-late time points for [18F]FDG (ICC, 0.69-0.75) and DOTATATE (ICC, 0.90-0.91). Conclusion: Ki ,max, cSUVmax, and cSURmax had low uptake time dependence compared with SUVmax and SURmax The Ki ,max can be predicted from cSURmax.

A co-ordinated transcriptional programme in the maternal liver supplies long chain polyunsaturated fatty acids to the conceptus using phospholipids.

The long and very long chain polyunsaturated fatty acids (LC-PUFAs) are preferentially transported by the mother to the fetus. Failure to supply LC-PUFAs is strongly linked with stillbirth, fetal growth restriction, and impaired neurodevelopmental outcomes. However, dietary supplementation during pregnancy is unable to simply reverse these outcomes, suggesting imperfectly understood interactions between dietary fatty acid intake and the molecular mechanisms of maternal supply. Here we employ a comprehensive approach combining untargeted and targeted lipidomics with transcriptional profiling of maternal and fetal tissues in mouse pregnancy. Comparison of wild-type mice with genetic models of impaired lipid metabolism allows us to describe maternal hepatic adaptations required to provide LC-PUFAs to the developing fetus. A late pregnancy-specific, selective activation of the Liver X Receptor signalling pathway dramatically increases maternal supply of LC-PUFAs within circulating phospholipids. Crucially, genetic ablation of this pathway in the mother reduces LC-PUFA accumulation by the fetus, specifically of docosahexaenoic acid (DHA), a critical nutrient for brain development.

Effect of antihypertensive deprescribing on hospitalisation and mortality: long-term follow-up of the OPTiMISE randomised controlled trial.

BACKGROUND: Deprescribing of antihypertensive medications is recommended for some older patients with low blood pressure and frailty. The OPTiMISE trial showed that this deprescribing can be achieved with no differences in blood pressure control at 3 months compared with usual care. We aimed to examine effects of deprescribing on longer-term hospitalisation and mortality. METHODS: This randomised controlled trial enrolled participants from 69 general practices across central and southern England. Participants aged 80 years or older, with systolic blood pressure less than 150 mm Hg and who were receiving two or more antihypertensive medications, were randomly assigned (1:1) to antihypertensive medication reduction (removal of one antihypertensive) or usual care. General practitioners and participants were aware of the treatment allocation following randomisation but individuals responsible for analysing the data were masked to the treatment allocation throughout the study. Participants were followed up via their primary and secondary care electronic health records at least 3 years after randomisation. The primary outcome was time to all-cause hospitalisation or mortality. Intention-to-treat analyses were done using Cox regression modelling. A per-protocol analysis of the primary outcome was also done, excluding participants from the intervention group who did not reduce treatment or who had medication reinstated during the initial trial 12-week follow-up period. This study is registered with the European Union Drug Regulating Authorities Clinical Trials Database (EudraCT2016-004236-38) and the ISRCTN Registry (ISRCTN97503221). FINDINGS: Between March 20, 2017, and Sept 30, 2018, a total of 569 participants were randomly assigned. Of these, 564 (99%; intervention=280; control=284) were followed up for a median of 4·0 years (IQR 3·7-4·3). Participants had a mean age of 84·8 years (SD 3·4) at baseline and 273 (48%) were women. Medication reduction was sustained in 109 participants at follow-up (51% of the 213 participants alive in the intervention group). Participants in the intervention group had a larger reduction in antihypertensives than the control group (adjusted mean difference -0·35 drugs [95% CI -0·52 to -0·18]). Overall, 202 (72%) participants in the intervention group and 218 (77%) participants in the control group experienced hospitalisation or mortality during follow-up (adjusted hazard ratio [aHR] 0·93 [95% CI 0·76 to 1·12]). There was some evidence that the proportion of participants experiencing the primary outcome in the per-protocol population was lower in the intervention group (aHR 0·80 [0·64 to 1·00]). INTERPRETATION: Half of participants sustained medication reduction with no evidence of an increase in all-cause hospitalisation or mortality. These findings suggest that an antihypertensive deprescribing intervention might be safe for people aged 80 years or older with controlled blood pressure taking two or more antihypertensives. FUNDING: British Heart Foundation and National Institute for Health and Care Research.

FOUND Trial: randomised controlled trial study protocol for case finding of obstructive sleep apnoea in primary care using a novel device.

INTRODUCTION: Obstructive sleep apnoea (OSA) is a common, but underdiagnosed, sleep disorder. If untreated, it leads to poor health outcomes, including Alzheimer's disease, cancer, cardiovascular disease and all-cause mortality. Our aim is to determine the feasibility and cost-effectiveness of moving the testing for OSA into general practice and how general practitioner (GP)-based screening affects overall detection rates. METHODS AND ANALYSIS: Randomised controlled trial of case finding of OSA in general practice using a novel Medicines and Healthcare products Regulatory Agency-registered device (AcuPebble SA100) compared with usual care with internal feasibility phase. A diverse sample of general practices (approximately 40) from across the West Midlands Clinical Research Network will identify participants from their records. Eligible participants will be aged 50-70 years with body mass index >30 kg/m2 and diabetes (type 1 or 2) and/or hypertension (office blood pressure >145/90 mm Hg or on treatment). They will exclude individuals with known OSA or chronic obstructive pulmonary disease, or those they deem unable to take part. After eligibility screening, consent and baseline assessment, participants will be randomised to either the intervention or control group. Participants in the intervention arm will receive by post the AcuPebble sleep test kit. Those in the control arm will continue with usual care. Follow-up questionnaires will be completed at 6 months. The study is powered (90%) to detect a 5% difference and will require 606 patients in each arm (713 will be recruited to each arm to allow for attrition). Due to the nature of the intervention, participants and GPs will not be blinded to the allocation. OUTCOMES: Primary: Detection rate of moderate-to-severe OSA in the intervention group versus control group. Secondary: Time to diagnosis and time to treatment for intervention versus control group for mild, moderate and severe OSA; cost-effectiveness analysis comparing the different testing pathways. ETHICS AND DISSEMINATION: The trial started on 1 November 2022. Ethical approval was granted from the South Central Oxford A Research Ethics Committee on 9 June 2023 (23/SC/0188) (protocol amendment version 1.3; update with amendment and approval to renumber to V2.0 on 29 August 2023). Patient recruitment began on 7 January 2024; initial planned end date will be on 31 April 2025.Results will be uploaded to the ISRCTN register within 12 months of the end of the trial date, presented at conferences, submitted to peer-reviewed journals and distributed via our patient and public involvement networks.The University of Warwick will act as the trial sponsor. The trial will be conducted in accordance with the Sponsor and Primary Care Clinical Trials Unit standard operating procedures. TRIAL REGISTRATION NUMBER: ISRCTN 16982033.

Characterizing phenotypes and clinical and health utilization associations of young people with chronic pain: latent class analysis using the electronic Persistent Pain Outcomes Collaboration database.

ABSTRACT: Using the Australiasian electronic Persistent Pain Outcomes Collaboration, a binational pain registry collecting standardized clinical data from paediatric ePPOC (PaedsePPOC) and adult pain services (AdultePPOC), we explored and characterized nationally representative chronic pain phenotypes and associations with clinical and sociodemographic factors, health care utilization, and medicine use of young people. Young people ≥15.0 and <25.0 years captured in PaedePPOC and AdultePPOC Australian data registry were included. Data from 68 adult and 12 paediatric pain services for a 5-year period January 2018 to December 2022 (first episode, including treatment information) were analysed. Unsupervised latent class analysis was applied to explore the existence of distinct pain phenotypes, with separate models for both services. A 3-phenotype model was selected from both paediatric and adult ePPOC data, with 693 and 3518 young people included, respectively (at least one valid indicator variable). Indicator variables for paediatric models were as follows: pain severity, functional disability (quasisurrogate "pain interference"), pain count, pain duration, pain-related worry (quasisurrogate "catastrophizing"), and emotional functioning; and, for adult models: pain severity, pain interference, pain catastrophizing, emotional functioning, and pain self-efficacy. From both services, 3 similar phenotypes emerged ("low," "moderate," "high"), characterized by an increasing symptom-severity gradient in multidimensional pain-related variables, showing meaningful differences across clinical and sociodemographic factors, health service utilization, and medicines use. Derived phenotypes point to the need for novel care models that differentially respond to the needs of distinct groups of young people, providing timely, targeted, age-appropriate care. To effectively scale such care, digital technologies can be leveraged to augment phenotype-informed clinical care.

Patlak Slope versus Standardized Uptake Value Image Quality in an Oncologic PET/CT Population: A Prospective Cross-Sectional Study.

Patlak slope (PS) images have the potential to improve lesion conspicuity compared with standardized uptake value (SUV) images but may be more artifact-prone. This study compared PS versus SUV image quality and hepatic tumor-to-background ratios (TBRs) at matched time points. Early and late SUV and PS images were reconstructed from dynamic positron emission tomography (PET) data. Two independent, blinded readers scored image quality metrics (a four-point Likert scale) and counted tracer-avid lesions. Hepatic lesions and parenchyma were segmented and quantitatively analyzed. Differences were assessed via the Wilcoxon signed-rank test (alpha, 0.05). Forty-three subjects were included. For overall quality and lesion detection, early PS images were significantly inferior to other reconstructions. For overall quality, late PS images (reader 1 [R1]: 3.95, reader 2 [R2]: 3.95) were similar (p > 0.05) to early SUV images (R1: 3.88, R2: 3.84) but slightly superior (p ≤ 0.002) to late SUV images (R1: 2.97, R2: 3.44). For lesion detection, late PS images were slightly inferior to late SUV images (R1 only) but slightly superior to early SUV images (both readers). PS-based TBRs were significantly higher than SUV-based TBRs at the early time point, with opposite findings at the late time point. In conclusion, late PS images are similar to early/late SUV images in image quality and lesion detection; the superiority of SUV versus PS hepatic TBRs is time-dependent.

Model misspecification, measurement error, and apparent supralinearity in the concentration-response relationship between PM2.5 and mortality.

A growing number of studies have produced results that suggest the shape of the concentration-response (C-R) relationship between PM2.5 exposure and mortality is "supralinear" such that incremental risk is higher at the lowest exposure levels than at the highest exposure levels. If the C-R function is in fact supralinear, then there may be significant health benefits associated with reductions in PM2.5 below the current US National Ambient Air Quality Standards (NAAQS), as each incremental tightening of the PM2.5 NAAQS would be expected to produce ever-greater reductions in mortality risk. In this paper we undertake a series of tests with simulated cohort data to examine whether there are alternative explanations for apparent supralinearity in PM2.5 C-R functions. Our results show that a linear C-R function for PM2.5 can falsely appear to be supralinear in a statistical estimation process for a variety of reasons, such as spatial variation in the composition of total PM2.5 mass, the presence of confounders that are correlated with PM2.5 exposure, and some types of measurement error in estimates of PM2.5 exposure. To the best of our knowledge, this is the first simulation-based study to examine alternative explanations for apparent supralinearity in C-R functions.

Australian physiotherapists attitudes, perceptions, and behaviours towards psychosocial screening tools: a qualitative interpretive description study.

PURPOSE: Psychosocial factors are a barrier to recovery for people with musculoskeletal pain and psychosocial screening tools are consistently recommended by best practice guidelines to assist in identification. However, many physiotherapists do not use these tools. Presently, the perspectives on psychosocial screening tools of Australian physiotherapists are unknown. Exploration of these factors may create targets for increased uptake. The purpose of this paper is to qualitatively explore Australian physiotherapists' attitudes, perceptions, and behaviours towards psychosocial screening tools for musculoskeletal pain conditions. MATERIALS AND METHODS: An Interpretive description qualitative study design was employed. Seventeen Australian physiotherapists were interviewed about their attitudes, perceptions, and behaviours towards psychosocial screening tools. Interviews were transcribed verbatim and analysed according to interpretive description. RESULTS: Analysis highlighted three major themes: (1) understanding the patient through psychosocial screening, (2) confidence and competence with psychosocial factors, and (3) factors outside of my control influence screening. CONCLUSIONS: This study presents a deeper understanding of Australian physiotherapists' diverse attitudes and practices regarding psychosocial screening tools. The research highlights not only the variability in perspectives towards the relevance of psychosocial factors in patient assessments, but also the influence of external elements such as patient demographics and clinic culture on the utilization of these screening methods.

Australian physiotherapists' varying attitudes and limited understanding of the impact of psychosocial factors may hinder the use of recommended psychosocial screening.Concerns about scope of practice, tool appropriateness for different patients, and clinic culture further challenge the integration of psychosocial assessments.The findings from this study indicate the need to provide more education to Australian physiotherapists on the importance and use of psychosocial risk factor screening, as part of clinical care standards and best practice guidelines in the management of patients, with musculoskeletal pain conditions.The findings from this study can support the creation of targeted training/innovations to improve the uptake of screening tools in Australian musculoskeletal clinical practice, to improve the care of patients with musculoskeletal pain conditions.

Test-Retest Repeatability of Patlak Slopes versus Standardized Uptake Values for Hypermetabolic Lesions and Normal Organs in an Oncologic PET/CT Population.

PURPOSE: We aimed to determine the test-retest repeatability of quantitative metrics based on the Patlak slope (PS) versus the standardized uptake value (SUV) among lesions and normal organs on oncologic [18F]FDG-PET/CT. PROCEDURES: This prospective, single-center study enrolled adults undergoing standard-of-care oncologic [18F]FDG-PET/CTs. Early (35-50 min post-injection) and late (75-90 min post-injection) SUV and PS images were reconstructed from dynamic whole-body PET data. Repeat imaging occurred within 7 days. Relevant quantitative metrics were extracted from lesions and normal organs. Repeatability was assessed via mean test-retest percent changes [T-RT %Δ], within-subject coefficients of variation (wCVs), and intra-class correlation coefficients (ICCs). RESULTS: Nine subjects (mean age, 61.7 ± 6.2 years; 6 females) completed the test-retest protocol. Four subjects collectively had 17 [18F]FDG-avid lesions. Lesion wCVs were higher (i.e., worse repeatability) for PS-early-max (16.2%) and PS-early-peak (15.6%) than for SUV-early-max (8.9%) and SUV-early-peak (8.1%), with similar early metric ICCs (0.95-0.98). Lesion wCVs were similar for PS-late-max (8.5%) and PS-late-peak (6.4%) relative to SUV-late-max (9.7%) and SUV-late-peak (7.2%), with similar late metric ICCs (0.93-0.98). There was a significant bias toward higher retest SUV and PS values in the lesion analysis (T-RT %Δ [95% CI]: SUV-late-max, 10.0% [2.6%, 17.0%]; PS-late-max, 20.4% [14.3%, 26.4%]) but not in the normal organ analysis. CONCLUSIONS: Among [18F]FDG-avid lesions, the repeatability of PS-based metrics is similar to equivalent SUV-based metrics at late post-injection time points, indicating that PS-based metrics may be suitable for tracking response to oncologic therapies. However, further validation is required in light of our study's limitations, including small sample size and bias toward higher retest values for some metrics.