The Relevance of Competences for a Healthy, Physically Active Lifestyle in Persons with Multiple Sclerosis: a Path Analytical Approach.

To promote health and counteract the decline associated with the disease, persons with multiple sclerosis (pwMS) are advised to lead healthy, physically active lifestyles. The physical activity-related health competence (PAHCO) model posits that individuals must meet three integrated, person-related requirements for the adoption of such a lifestyle: movement competence, control competence, and self-regulation competence. To gain insights into the needs and challenges of pwMS, the goal of the present study was to empirically examine the roles of these competences within this target group. A total of 475 pwMS underwent a multidimensional, online-based assessment of PAHCO. These participants self-reported their amount of physical activity (PA), health status, disease-related, and sociodemographic information. We used a series of path analyses to investigate the relevance of the three competence areas for each individual's PA level and subjective health. Stepwise multivariate analyses revealed that self-regulation competence was significantly associated with overall PA volume. In contrast, movement competence did not contribute to this prediction. Control competence was also not related to PA level. However, in accordance with the PAHCO model, this factor exerted an independent, qualitative effect on participant health. In summary, self-regulation competence appears to play a crucial role with regard to PA volume. Specifically, control competence appears to be key for the qualitative aspect of PA promotion, characterizing the individual's application of an appropriate stimulus for the achievement of health. Integrating the promotion of self-regulation and control competences into rehabilitation practices can help to foster healthy, physically active lifestyles in pwMS.Supplemental data for this article is available online at https://doi.org/10.1080/08964289.2021.1935437 .

[Dissemination of National Physical Activity Recommendations: Participatory Development of Dissemination Strategies in Germany]. / Disseminierung der Nationalen Bewegungsempfehlungen: Partizipative Entwicklung von Disseminierungsstrategien in Deutschland.

BACKGROUND: In 2016, the first evidence-based National Recommendations for Physical Activity and Physical Activity Promotion were published in Germany. These recommendations are primarily intended for experts, decision makers and stakeholders. OBJECTIVES: This study aims to describe the development of dissemination strategies for these recommendations. PROCESS: To facilitate the co-production of knowledge between practitioners, decision makers, and researchers, a participatory approach was applied. This approach involved the development of target group-specific strategies for disseminating the recommendations. This was achieved in two workshops and one working group phase; 92 professionals and decision makers participated in the process. RESULTS: The working groups developed specific dissemination strategies that were grouped into the following strategy types: (1) inform multipliers, (2) activate multipliers, (3) use existing and develop new networks, (4) initiate policy change. CONCLUSION: The participatory approach adopted in this project was successful in developing dissemination strategies and is unique from an international perspective. To improve the evaluation of such co-production processes, future research should determine and operationalize appropriate indicators.

How can the impact of national recommendations for physical activity be increased? Experiences from Germany.

BACKGROUND: Clearly stated national recommendations for physical activity (PA) are available in many nations. Yet, their impact on national level policy-making might be considered modest at best. This paper analyses the approach selected to curtail this problem in Germany. MAIN TEXT: Academics, government institutions and relevant stakeholders worked in collaboration to produce a series of national recommendations for PA and PA promotion published in 2016. Since their publication, these recommendations have achieved a measurable political impact through a systematic approach focused on dissemination and implementation strategies. For example, the German Conference of Health Ministers has acknowledged the national recommendations, endorsed their dissemination and proposed that they are included in measures within the Federal Prevention Act. CONCLUSION: Since their publication, the national recommendations have yielded satisfactory political impact. The contributing aspects might partially be explained by the Multiple Streams Approach.

Implementation and dissemination of physical activity-related health competence in vocational nursing training: study protocol for a cluster-randomized controlled intervention trial.

BACKGROUND: Although the nursing sector gains growing importance in an aging society, students representing the future workforce often show insufficient health. Acknowledging the health-enhancing effects of adequate physical activity, the educational system in Bavaria, Germany, has recently integrated the promotion of physical activity-related health competence (PAHCO) into the nursing curriculum. However, it cannot be assumed that PAHCO has sufficiently permeated the educational practices and routines of the nursing schools. Therefore, the goal of the present study is to examine and compare the effectiveness as well as implementation of different intervention approaches to address PAHCO in the Bavarian nursing school system. METHODS: We randomly assign 16 nursing schools (cluster-based) to four study arms (bottom-up, top-down led by teachers, top down led by external physical activity experts, control group). Schools in intervention group 1 (IG-1) develop multicomponent inventions to target PAHCO via cooperative planning (preparation, planning, and implementation phase). Intervention groups 2 and 3 (IG-2, IG-3) receive both an expert-based intervention (developed through intervention mapping) via trained mediators to address PAHCO. External physical activity experts deliver the structured PAHCO intervention in IG-2, while teachers from the nursing schools themselves conduct the PAHCO intervention in IG-3. In line with a hybrid effectiveness implementation trial, we apply questionnaire-based pre-post measurements across all conditions (sample size calculation: nfinal = 636) to examine the effectiveness of the intervention approaches and, simultaneously, draw on questionnaires, interview, and protocol data to examine their implementation. We analyze quantitative effectiveness data via linear models (times-group interaction), and implementation data using descriptive distributions and content analyses. CONCLUSION: The study enables evidence-based decisions about the suitability of three intervention approaches to promote competencies for healthy, physically active lifestyles among nursing students. The findings inform dissemination activities to effectively reach all 185 schools of the Bavarian nursing system. TRIAL REGISTRATION: Clinical trials NCT05817396. Registered on April 18, 2023.

Diagnostic accuracy of dual-time-point 18F-FDG PET/CT for the detection of axillary lymph node metastases in breast cancer patients.

BACKGROUND: The diagnostic accuracy of FDG-PET/CT for the detection of axillary lymph node metastases in breast cancer patients acquired 60 min after FDG administration is reported to be only moderate, especially due to low sensitivity. PURPOSE: To test whether a delayed scan 90 min after FDG administration could enhance the diagnostic accuracy of FDG-PET/CT for the detection of axillary lymph node metastases. MATERIAL AND METHODS: Thirty-eight women suffering from primary breast cancer (mean age 52 years; range 25-78 years; standard deviation 14 years) underwent a pre-therapeutic dual-time-point FDG-PET/CT scan. The maximum standardized uptake value (SUVmax) of axillary lymph nodes was measured at two different time points (time point T1: 60 min after FDG injection, time point T2: 90 min after FDG injection). SUVmax of axillary lymph nodes at T1 and T2 were assessed for statistical significance using a paired Wilcoxon-Test (P < 0.05). At T1 a qualitative analysis of the FDG-PET/CT scan was performed to define physiologic and metastatic lymph nodes. At T2 an increase of the SUVmax of at least 3.75% over time was rated as indicating malignancy. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and the accuracy of FDG-PET/CT for the detection of axillary lymph node metastases was calculated at time points T1 and T2. Statistically significant differences were determined using Fisher's exact test (P < 0.05). Histopathology served as the standard of reference. A compartment based analysis was done. RESULTS: Axillary lymph nodes had a mean SUVmax of 1.6 (range 0.6-10.8; SD 1.9) at T1 and a mean SUVmax of 1.8 (range 0.5-17.9; SD 3.5) at T2. This difference was statistically significant (P = 0.047). The sensitivity, specificity, PPV, NPV, and accuracy of FDG-PET/CT for the detection of axillary lymph node metastases was 81%, 100%, 100%, 88%, and 92% at T1, and 88%, 50%, 56%, 85%, and 66% at T2, respectively. This difference was not statistically significant (P = 0.27). CONCLUSION: There is a slight increase of the FDG accumulation of axillary lymph nodes between 60 and 90 min after FDG administration. This increase did not translate into a statistical significant enhancement of the diagnostic accuracy of FDG-PET/CT for the detection of axillary lymph nodes. Especially due to false-positive results a delayed FDG-PET/CT scan 90 min after FDG administration is not able to enhance the diagnostic accuracy for the detection of lymph node metastases.

Comparison of the diagnostic value of FDG-PET/CT and axillary ultrasound for the detection of lymph node metastases in breast cancer patients.

BACKGROUND: FDG-PET/CT is increasingly being used for breast cancer staging. Its diagnostic accuracy in comparison to ultrasound as the standard non-invasive imaging modality for the evaluation of axillary lymph nodes has yet not been evaluated. PURPOSE: To retrospectively compare the diagnostic value of full-dose, intravenously contrast-enhanced FDG-PET/CT and ultrasound for the detection of lymph node metastases in breast cancer patients. MATERIAL AND METHODS: Ninety patients (one patient with a bilateral carcinoma) (89 women, one man; mean age, 55.5 +/- 16.6 years) suffering from primary breast cancer underwent whole-body FDG-PET/CT and axillary ultrasound. The ipsilateral axillary fossa (n = 91) was evaluated for metastatic spread. The sensitivity, specificity, the positive predictive value (PPV), negative predictive value (NPV), and accuracy of both methods were calculated. The sensitivity and accuracy were statistically compared using the McNemar Test (P <0.05). Analyses were made on a patient basis. The number of patients with extra-axillary locoregional lymph node metastases exclusively detected by FDG-PET/CT was evaluated. For axillary lymph node metastases histopathology served as the reference standard. RESULTS: The sensitivity, specificity, PPV, NPV, and accuracy of FDG-PET/CT for the detection of axillary lymph node metastases were 54%, 89%, 77%, 74%, and 75%, respectively. For ultrasound it was 38%, 78%, 54%, 65%, and 62%, respectively. FDG-PET/CT was significantly more accurate than ultrasound for the detection of axillary lymph node metastases (P = 0.019). There was no statistically significant difference between the sensitivity of both modalities (P = 0.0578). FDG-PET/CT detected extra-axillary locoregional lymph node metastases in seven patients (8%) that had not been detected by another imaging modality. CONCLUSION: Though more accurate compared to ultrasound for evaluating the axillary lymph node status FDG-PET/CT is only as sensitive as ultrasound when it comes to the detection of axillary lymph node metastases. Due to the low sensitivity FDG-PET/CT cannot act as a substitute for Sentinel lymph node biopsy. FDG-PET/CT is able to detect previously unknown locoregional extra-axillary lymph node metastases.

Interventions simultaneously promoting social participation and physical activity in community living older adults: A systematic review.

Background: In recent years, there has been a global trend toward an increase in life expectancy and the proportion of elderly people among the population. In this regard, it becomes important to promote active and healthy aging. Physical inactivity and social isolation are both risk factors of many chronic illnesses and highly prevalent in older adults. This challenges communities to develop interventions that reduce these risk factors among elderly populations. The main aims of this study were to summarize community-based interventions that aim to simultaneously promote social participation and physical activity in older adults and to examine their effects. Methods: We performed a systematic review based on the PRISMA standards. Literature searches were conducted in six scientific databases in July 2021. Articles were included if they had an interventional design, focused on older adults living in the community and measured social participation and physical activity as an outcome. The data were summarized narratively due to the heterogeneity of studies and the variety of outcome measures. Results: Overall, 46 articles published in English were included. The studies were grouped in (1) interventions with main focus on physical activity promotion; (2) social activities that included a physical activity component; (3) health behavior interventions/ health education interventions; (4) multicomponent interventions; (5) environmental interventions. The majority of the reviewed studies reported positive effects of interventions on physical activity and/or social participation. No study reported negative effects. Analysis of quantitative studies showed that multicomponent interventions have great positive effects on both outcomes. In qualitative studies positive effects were found regardless of intervention type. Conclusion: This review summarizes the evidence about the effects of community-based interventions that aim to promote social participation and physical activity in older adults. Multicomponent interventions seem to be most suitable for simultaneous promotion of physical activity and social participation. However, high variability in measurement methods used to assess both social participation and physical activity in the included studies made it difficult to compare studies and to indicate the most effective. Systematic review registration: www.crd.york.ac.uk, identifier: PROSPERO [CRD42021268270].

Diagnosis and dosimetry in differentiated thyroid carcinoma using 124I PET: comparison of PET/MRI vs PET/CT of the neck.

PURPOSE: This study compares intrinsically coregistered 124I positron emission tomography (PET) and CT (PET/CT) and software coregistered 124I PET and MRI (PET/MRI) images for the diagnosis and dosimetry of thyroid remnant tissues and lymph node metastases in patients with differentiated thyroid carcinoma (DTC). METHODS: After thyroidectomy, 33 high-risk DTC patients (stage III or higher) received 124I PET/CT dosimetry prior to radioiodine therapy to estimate the absorbed dose to lesions and subsequently underwent a contrast-enhanced MRI examination of the neck. Images were evaluated by two experienced nuclear medicine physicians and two radiologists to identify the lesions and to categorize their presumable provenience, i.e. thyroid remnant tissue (TT), lymph node metastasis (LN) and inconclusive tissue. The categorization and dosimetry of lesions was initially performed with PET images alone (PET only). Subsequently lesions were reassessed including the CT and MRI data. RESULTS: The analyses were performed on a patient and on a lesion basis. Patient-based analyses showed that 26 of 33 (79%) patients had at least one lesion categorized as TT on PET only. Of these patients, 11 (42%) and 16 (62%) had a morphological correlate on CT and MRI, respectively, in at least one TT PET lesion. Twelve patients (36%) had at least one lesion classified as LN on PET only. Nine (75%) of these patients had a morphological correlate on both CT and MRI in at least one LN PET lesion. Ten patients (30%) showed at least one lesion on PET only classified as inconclusive. The classification was changed to a clear classification in two patients (two LN) by CT and in four (two TT, two LN) patients by MRI. Lesion-based analyses (n=105 PET positive lesions) resulted in categorization as TT in 61 cases (58%), 16 (26%) of which had a morphological correlate on CT and 33 (54%) on MRI. A total of 29 lesions (27%) were classified as LN on PET, 18 (62%) of which had a morphological correlate on CT and 24 (83%) on MRI. In 16 lesions (15%) PET alone allowed no definite categorization. Categorization was achieved with the aid of CT and MRI, respectively, in five (one TT, four LN) and in six (two TT, four LN) lesions. In direct comparison, 23 lesions were not discernible on CT but clearly visible on MRI, 15 of which were smaller than 10 mm and about two thirds were classified as TT. Redoing dosimetry based on the volume information from MRI for these small lesions would have changed the initial therapy regime in five patients. These patients would have received (131)I therapy with standardized activities of 3.7 GBq or 7.4 GBq instead of activities higher than 10 GBq and would have benefited from reduced radiation exposure. CONCLUSION: PET/MRI is superior to PET/CT in terms of tracing back a PET focus to a morphological correlate. For this reason PET/MRI enhances diagnostic certainty for lesions<10 mm and improves pretherapeutic lesion dosimetry in DTC.

The Two-Minute Walk Test in Persons with Multiple Sclerosis: Correlations of Cadence with Free-Living Walking Do Not Support Ecological Validity.

The two-minute walk test (2MWT) is a frequently used walking capacity test in persons with multiple sclerosis (pwMS). However, less is known about its relevance with regards to walking capacity during free-living walking performance. Therefore, the ecological validity of the 2MWT was tested by 1. computing free-living minutes with the same intensity (cadence) as during the 2MWT and 2. investigating the relationship between 2MWT cadence and minutes with the same cadence during free-living walking. 20 pwMS aged 44.2 ± 12.2 (Expanded Disability Status Scale (EDSS) score of 3.1 ± 1.4) performed a 2MWT and wore an accelerometer for seven days. The number of pwMS reaching 100%, 90%, 80% or 70% of 2MWT cadence for at least one minute a day and minutes/day with at least 100%, 90%, 80% and 70% of 2MWT cadence during free-living walking was calculated. Six participants reached 100% of the 2MWT cadence for at least one minute/day during free-living walking. A total of 80% 2MWT cadence was the first intensity category that was reached by all participants during free-living walking. No significant correlation was found between cadence in the 2MWT and minutes in which this cadence was reached during free-living walking. Ecological validity with regard to walking intensity could not be confirmed in our study sample.

Validity of Consumer Activity Monitors and an Algorithm Using Smartphone Data for Measuring Steps during Different Activity Types.

Background: Consumer activity monitors and smartphones have gained relevance for the assessment and promotion of physical activity. The aim of this study was to determine the concurrent validity of various consumer activity monitor models and smartphone models for measuring steps. Methods: Participants completed three activity protocols: (1) overground walking with three different speeds (comfortable, slow, fast), (2) activities of daily living (ADLs) focusing on arm movements, and (3) intermittent walking. Participants wore 11 activity monitors (wrist: 8; hip: 2; ankle: 1) and four smartphones (hip: 3; calf: 1). Observed steps served as the criterion measure. The mean average percentage error (MAPE) was calculated for each device and protocol. Results: Eighteen healthy adults participated in the study (age: 28.8 ± 4.9 years). MAPEs ranged from 0.3-38.2% during overground walking, 48.2-861.2% during ADLs, and 11.2-47.3% during intermittent walking. Wrist-worn activity monitors tended to misclassify arm movements as steps. Smartphone data collected at the hip, analyzed with a separate algorithm, performed either equally or even superiorly to the research-grade ActiGraph. Conclusion: This study highlights the potential of smartphones for physical activity measurement. Measurement inaccuracies during intermittent walking and arm movements should be considered when interpreting study results and choosing activity monitors for evaluation purposes.

Thoracic staging in lung cancer: prospective comparison of 18F-FDG PET/MR imaging and 18F-FDG PET/CT.

UNLABELLED: Therapeutic decisions in non-small cell lung cancer (NSCLC) patients depend on the tumor stage. PET/CT with (18)F-FDG is widely accepted as the diagnostic standard of care. The purpose of this study was to compare a dedicated pulmonary (18)F-FDG PET/MR imaging protocol with (18)F-FDG PET/CT for primary and locoregional lymph node staging in NSCLC patients using histopathology as the reference. METHODS: Twenty-two patients (12 men, 10 women; mean age ± SD, 65.1 ± 9.1 y) with histopathologically confirmed NSCLC underwent (18)F-FDG PET/CT, followed by (18)F-FDG PET/MR imaging, including a dedicated pulmonary MR imaging protocol. T and N staging according to the seventh edition of the American Joint Committee on Cancer staging manual was performed by 2 readers in separate sessions for (18)F-FDG PET/CT and PET/MR imaging, respectively. Results from histopathology were used as the standard of reference. The mean and maximum standardized uptake value (SUV(mean) and SUV(max), respectively) and maximum diameter of the primary tumor was measured and compared in (18)F-FDG PET/CT and PET/MR imaging. RESULTS: PET/MR imaging and (18)F-FDG PET/CT agreed on T stages in 16 of 16 of patients (100%). All patients were correctly staged by (18)F-FDG PET/CT and PET/MR (100%), compared with histopathology. There was no statistically significant difference between (18)F-FDG PET/CT and (18)F-FDG PET/MR imaging for lymph node metastases detection (P = 0.48). For definition of thoracic N stages, PET/MR imaging and (18)F-FDG PET/CT were concordant in 20 of 22 patients (91%). PET/MR imaging determined the N stage correctly in 20 of 22 patients (91%). (18)F-FDG PET/CT determined the N stage correctly in 18 of 22 patients (82%). The mean differences for SUV(mean) and SUV(max) of NSCLC in (18)F-FDG PET/MR imaging and (18)F-FDG PET/CT were 0.21 and -5.06. These differences were not statistically significant (P > 0.05). The SUV(mean) and SUV(max) measurements derived from (18)F-FDG PET/CT and (18)F-FDG PET/MR imaging exhibited a high correlation (R = 0.74 and 0.86, respectively; P < 0.0001). Size measurements showed an excellent correlation between (18)F-FDG PET/MR imaging and (18)F-FDG PET/CT (R = 0.99; P < 0.0001). The lower and upper limits of agreement between (18)F-FDG PET/CT and (18)F-FDG PET/MR imaging using Bland-Altman analysis were -2.34 to 3.89 for SUV(mean), -7.42 to 4.40 for SUV(max), and -0.59 to 0.83 for the tumor size, respectively. CONCLUSION: (18)F-FDG PET/MR imaging using a dedicated pulmonary MR imaging protocol, compared with (18)F-FDG PET/CT, does not provide advantages in thoracic staging in NSCLC patients.

Depiction and characterization of liver lesions in whole body [¹8F]-FDG PET/MRI.

OBJECTIVES: To assess the value of PET/MRI with [(18)F]-FDG using a whole body protocol for the depiction and characterization of liver lesions in comparison to PET/CT. METHODS: 70 patients (31 women, 39 men) with solid tumors underwent [(18)F]-FDG PET/CT and followed by an additional PET/MRI using an integrated scanner. Two readers rated the datasets (PET/CT; PET/MRI) regarding conspicuity of hepatic lesions (4-point ordinal scale) and diagnostic confidence (5-point ordinal scale). Median scores for lesion conspicuity and diagnostic confidence were compared using Wilcoxon's rank sum test. Prior examinations, histopathology and clinical follow-up (116 ± 54 days) served as standard of reference. RESULTS: 36 of 70 (51%) patients showed liver lesions. Using PET/CT and PET/MRI all patients with liver metastases could correctly be identified. A total of 97 lesions were found (malignant n=26; benign n=71). For lesion conspicuity significantly higher scores were obtained for PET/MRI in comparison to PET/CT (p<0.001). Significantly better performance for diagnostic confidence was observed in PET/MRI, both for malignant as for benign lesions (p<0.001). CONCLUSIONS: PET/MRI, even in the setting of a whole body approach, provides higher lesion conspicuity and diagnostic confidence compared to PET/CT and may therefore evolve as an attractive alternative in oncologic imaging.

Hybrid [¹8F]-FDG PET/MRI including non-Gaussian diffusion-weighted imaging (DWI): preliminary results in non-small cell lung cancer (NSCLC).

PURPOSE: To assess the feasibility of non-Gaussian DWI as part of a FDG-PET/MRI protocol in patients with histologically proven non-small cell lung cancer. MATERIAL AND METHODS: 15 consecutive patients with histologically proven NSCLC (mean age 61 ± 11 years) were included in this study and underwent whole-body FDG-PET/MRI following whole-body FDG-PET/CT. As part of the whole-body FDG-PET/MRI protocol, an EPI-sequence with 5 b-values (0, 100, 500, 1000 and 2000 s/mm(2)) was acquired for DWI of the thorax during free-breathing. Volume of interest (VOI) measurements were performed to determine the maximum and mean standardized uptake value (SUV(max); SUV(mean)). A region of interest (ROI) was manually drawn around the tumor on b=0 images and then transferred to the corresponding parameter maps to assess ADC(mono), D(app) and K(app). To assess the goodness of the mathematical fit R(2) was calculated for monoexponential and non-Gaussian analysis. Spearman's correlation coefficients were calculated to compare SUV values and diffusion coefficients. A Student's t-test was performed to compare the monoexponential and non-Gaussian diffusion fitting (R(2)). RESULTS: T staging was equal between FDG-PET/CT and FDG-PET/MRI in 12 of 15 patients. For NSCLC, mean ADC(mono) was 2.11 ± 1.24 × 10(-3) mm(2)/s, Dapp was 2.46 ± 1.29 × 10(-3) mm(2)/s and mean Kapp was 0.70 ± 0.21. The non-Gaussian diffusion analysis (R(2)=0.98) provided a significantly better mathematical fitting to the DWI signal decay than the monoexponetial analysis (R(2)=0.96) (p<0.001). SUV(max) and SUV(mean) of NSCLC was 13.5 ± 7.6 and 7.9 ± 4.3 for FDG-PET/MRI. ADC(mono) as well as Dapp exhibited a significant inverse correlation with the SUV(max) (ADC(mono): R=-0.67; p<0.01; Dapp: R=-0.69; p<0.01) as well as with SUV(mean) assessed by FDG-PET/MRI (ADC(mono): R=-0.66; p<0.01; Dapp: R=-0.69; p<0.01). Furthermore, Kapp exhibited a significant correlation with SUV(max) (R=0.72; p<0.05) and SUV(mean) as assessed by FDG-PET/MRI (R=0.71; p<0.005). CONCLUSION: Simultaneous PET and non-Gaussian diffusion acquisitions are feasible. Non-Gaussian diffusion parameters show a good correlation with SUV and might provide additional information beyond monoexponential ADC, especially as non-Gaussian diffusion exhibits better mathematical fitting to the decay of the diffusion signal than monoexponential DWI.

Diagnostic accuracy of virtual 18F-FDG PET/CT bronchoscopy for the detection of lymph node metastases in non-small cell lung cancer patients.

UNLABELLED: The aim of this study was to determine the diagnostic accuracy of (18)F-FDG PET/CT bronchoscopy for the detection of regional lymph node metastases in non-small cell lung cancer (NSCLC) patients; potential differences in the maximum standardized uptake value (SUVmax), mean SUV (SUVmean), short-axis diameter, and distance to the airways when comparing true-positive (TP), false-positive (FP), true-negative (TN), and false-negative (FN) lymph nodes; the smallest bronchus diameter accessible by virtual bronchoscopy; and the duration from the start of the virtual (18)F-FDG PET/CT bronchoscopy viewing tool until the images were displayed. METHODS: Sixty-one consecutive NSCLC patients (mean age ± SD, 58 ± 10 y) underwent whole-body (18)F-FDG PET/CT. From these data, virtual (18)F-FDG PET/CT bronchoscopies were reconstructed. The duration from the start of the tool until the display of virtual bronchoscopy images was determined. The diagnostic accuracy of (18)F-FDG PET/CT bronchoscopy for the detection of regional lymph node metastases was evaluated on a lesion basis. Axial (18)F-FDG PET/CT scans served as the standard of reference. The SUVmax, SUVmean, short-axis diameter, and distance to the airways of regional lymph nodes were measured. Lymph nodes were classified as TP, FP, TN, and FN. The smallest bronchus diameter accessible by (18)F-FDG PET/CT bronchoscopy was measured. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of virtual (18)F-FDG PET/CT bronchoscopy for the detection of lymph node metastases were 76%, 87%, 85%, 79%, and 81%, respectively. The differences between the SUVmax, SUVmean, short-axis diameter, and distance to the airways of TP and FP as well as TN and FN lymph nodes were statistically significant (P < 0.05). The mean smallest diameter of accessible bronchi by (18)F-FDG PET/CT bronchoscopy was 3 mm. The mean time duration from the start of the virtual (18)F-FDG PET/CT bronchoscopy tool until the display of the images was 22 ± 7 s. CONCLUSION: Virtual fly-through 3-dimensional (18)F-FDG PET/CT bronchoscopy yields a high diagnostic accuracy for the detection of regional lymph node metastases and has access to bronchi even in the periphery of the lung. High SUVmax, high SUVmean, large small-axis diameter, and short distance to the airways aid detection of lymph node metastases with (18)F-FDG PET/CT bronchoscopy.

Time course of tumor SUV in 18F-FDG PET of breast cancer: presentation of a simple model using a single reference point for time corrections of tumor SUVs.

UNLABELLED: Tumor standardized uptake values (SUVs) vary with the interval between 18F-FDG injection and image acquisition. This paper presents a simple method using a single reference point to make appropriate time corrections for tumor SUVs. METHODS: The reference point method was algebraically deduced from observations made by Beaulieu et al., who found that tumor SUVs behaved linearly over time (∼30 to 75 min after 18F-FDG injection). Eighteen patients with breast cancer were dynamically examined with PET/CT (∼60 and 80 min after 18F-FDG injection). Maximum SUV was calculated by applying 2 different iterative reconstruction methods (high-definition reconstruction and attenuation-weighted ordered-subsets expectation maximization). Reference points for time corrections were given, and errors for corrections obtained with the reference point method were calculated. RESULTS: Variations in the reconstruction algorithm strongly influenced the coordinates of the reference point. Time corrections using the reference point method were more accurate at higher tumor SUVs (>8 at high-definition reconstruction and>6 at attenuation-weighted ordered-subsets expectation maximization) than at lower ones. CONCLUSION: A common origin of tumor SUVs over time exists in breast cancer. In combination with the linear behavior of tumor SUVs between approximately 30 and 80 min, such a reference point allows for straightforward time corrections of tumor SUVs. Parameters for image reconstruction must be considered because they influence the coordinates of the reference point.

Metabolic imaging allows early prediction of response to vandetanib.

UNLABELLED: The RET (rearranged-during-transfection protein) protooncogene triggers multiple intracellular signaling cascades regulating cell cycle progression and cellular metabolism. We therefore hypothesized that metabolic imaging could allow noninvasive detection of response to the RET inhibitor vandetanib in vivo. METHODS: The effects of vandetanib treatment on the full-genome expression and the metabolic profile were analyzed in the human medullary thyroid cancer cell line TT. In vitro, transcriptional changes of pathways regulating cell cycle progression and glucose, dopa, and thymidine metabolism were correlated to the results of cell cycle analysis and the uptake of (3)H-deoxyglucose, (3)H-3,4-dihydroxy-L-phenylalanine, and (3)H-thymidine under vandetanib treatment. In vivo, the tumor metabolism under vandetanib was monitored by small-animal PET of tumor-bearing mice. RESULTS: Vandetanib treatment resulted in the transcriptional downregulation of various effector pathways with consecutive downregulation of cyclin expression and a G(0)/G(1) arrest. In vitro, vandetanib treatment resulted in the decreased expression of genes regulating glucose, 3,4-dihydroxy-L-phenylalanine, and thymidine metabolism, with a subsequent reduction in the functional activity of the corresponding pathways. In vivo, metabolic imaging with PET was able to assess changes in the tumoral glucose metabolism profile as early as 3 d after initiation of vandetanib treatment. CONCLUSION: We describe a metabolic imaging approach for the noninvasive detection of successful vandetanib treatment. Our results suggest that PET may be useful for identifying patients who respond to vandetanib early in the course of treatment.