Radiopharmaceuticals for Skeletal Muscle PET Imaging.

The skeletal muscles account for approximately 40% of the body weight and are crucial in movement, nutrient absorption, and energy metabolism. Muscle loss and decline in function cause a decrease in the quality of life of patients and the elderly, leading to complications that require early diagnosis. Positron emission tomography/computed tomography (PET/CT) offers non-invasive, high-resolution visualization of tissues. It has emerged as a promising alternative to invasive diagnostic methods and is attracting attention as a tool for assessing muscle function and imaging muscle diseases. Effective imaging of muscle function and pathology relies on appropriate radiopharmaceuticals that target key aspects of muscle metabolism, such as glucose uptake, adenosine triphosphate (ATP) production, and the oxidation of fat and carbohydrates. In this review, we describe how [18F]fluoro-2-deoxy-D-glucose ([18F]FDG), [18F]fluorocholine ([18F]FCH), [11C]acetate, and [15O]water ([15O]H2O) are suitable radiopharmaceuticals for diagnostic imaging of skeletal muscles.

COVID-19 Outcome and Tobacco Product Use: Case-Control and Retrospective Cohort Studies Using Nationwide Samples.

BACKGROUND: Conflicting evidence exists regarding the association between smoking and the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We investigated the association between combustible cigarette (CC) smoking, noncombustible tobacco product (NCTP) use, and the use of any tobacco product with various coronavirus disease 2019 (COVID-19) outcomes. METHODS: A case-control study was conducted using the Korea Disease Control and Prevention Agency-COVID19-National Health Insurance Service (NHIS) cohort. A retrospective cohort study was conducted using 12,571,698 individuals from the NHIS cohort. Logistic regression evaluated the association between CC smoking, NCTP use, and use of any tobacco product with SARS-CoV-2 infection. Poisson regression evaluated the association between these forms of tobacco product use and COVID-19-related hospitalization and mortality. RESULTS: In the case-control study, we identified 30,878 cases of SARS-CoV-2 infection. The odds ratios (95% confidence intervals [CIs]) for SARS-CoV-2 infection were lower among current CC smokers (0.51, 0.48-0.54), current- and former-NCTP users (0.80, 0.74-0.88; 0.82, 0.74-0.91), and current users of any tobacco product (0.52, 0.49-0.55) relative to never user controls. In retrospective cohort study, we identified 16,521 COVID-19-related hospitalization and 362 COVID-19-related deaths. The relative risks (95% CIs) for COVID-19-related hospitalization were lower among current CC smokers (0.51, 0.48-0.54) and current users of any tobacco product (0.53, 0.50-0.56) relative to never user controls. There was no association between the use of tobacco product and COVID-19-related mortality. CONCLUSION: Current CC smokers and current users of any tobacco product showed reduced risk of SARS-CoV-2 infection and COVID-19-related hospitalization. It remains uncertain whether these relationships are causal.

Efficacy of preoperative lymphoscintigraphy in predicting surgical outcomes of lymphaticovenous anastomosis in lower extremity lymphedema: Clinical correlations in gynecological cancer-related lymphedema.

BACKGROUND: Lymphaticovenous anastomosis (LVA) is a promising microsurgical treatment for lower extremity lymphedema (LEL). Lymphoscintigraphy effectively assesses lower limb lymphatic systems before LVA, but its role in predicting the therapeutic outcomes of LVA is indeterminate. In this study we investigate the efficacy of preoperative lymphoscintigraphy using clinical findings to predict outcomes in gynecological cancer-related LEL patients who underwent LVA. METHODS: A retrospective review was conducted on consecutive gynecological cancer patients with LEL who had undergone LVA between June 2018 and June 2021. The therapeutic efficacy was assessed by measuring the change rate of the lower extremity lymphedema index (LELi) six months after surgery. Clinical data and lymphoscintigraphic findings were analyzed to assess therapeutic efficacy of LVA. RESULTS: Out of the 60 evaluated legs, 83.3% of the legs showed improved results after LVA. Univariable linear regression analysis revealed that higher preoperative LELi, and ovarian cancer were associated with superior LELi change rate (LC rate). Absence of dermal backflow (DBF) on lymphoscintigraphy was associated with inferior LC rate. Multivariable linear regression analysis identified ovarian cancer and higher preoperative LELi were independently correlated with favorable outcomes, while the absence of DBF was independently correlated with inferior outcomes. CONCLUSION: The results of this study emphasizes the effectiveness of preoperative lymphoscintigraphy, preoperative LELi, and primary malignancy as predictors of LVA outcomes in gynecological cancer-related LEL patients.

Value of Quantitative Salivary Gland SPECT/CT for the Detection of Saliva Leakage.

ABSTRACT: A 47-year-old woman presented to our emergency department with a 10-day history of pain, halitosis, and swelling below the left jaw. The patient was diagnosed with left sialadenitis and left submandibular abscess by tissue biopsy. An otolaryngologist performed transcervical incision and drainage of the abscess 1 day after admission. Postoperatively, the patient complained of a sensation of fluid leakage from the mouth, and a continuous purulent discharge was observed. One month postoperatively, a salivary gland scan and SPECT/CT were performed to investigate the sialorrhea and the cause of the discharge. Salivary gland SPECT/CT images localized the saliva leakage site.

The added value of SPECT/CT lymphoscintigraphy in the initial assessment of secondary extremity lymphedema patients.

An added value of SPECT/CT over planar lymphoscintigraphy for initial staging in patients with secondary extremity lymphedema was investigated. Furthermore, we developed a hybrid SPECT/CT classification combining dermal backflow (DBF) of SPECT and honeycomb pattern (HP) of CT, correlated it with lymphoscintigraphic staging and clinical severity. Forty-one patients with secondary extremity lymphedema who underwent lymphoscintigraphy with SPECT/CT were included retrospectively. The severity of extremity lymphedema was assessed using CT volumetry. Lymphoscintigraphic findings were evaluated using the Taiwan Lymphoscintigraphy Staging (TLS), and CT-based and SPECT-based quantitative analysis were performed. TLS was performed by planar scintigraphy only and with SPECT/CT, respectively. The SPECT/CT findings were classified into DBF-/HP-, DBF+/HP-, DBF+/HP+, and DBF-/HP+. Based on these findings, patients were categorized into five classes: Class 1 = DBF-HP- entire limb, Class 2 = DBF+/HP- proximal/distal limb without DBF+/HP+ or DBF-/HP+, Class 3 = DBF+/HP+ proximal/distal limb without DBF-/HP+, Class 4 = Mixed DBF+/HP+ and DBF-/HP+ in proximal/distal limb, Class 5 = DBF-/HP+ entire limb. Adding SPECT/CT to planar scintigraphy showed a 15.4% modification rate in lymphoscintigraphic staging. HP volume ratio significantly increased as clinical severity and lymphoscintigraphic staging increased, while DBF volume ratio increased with severity and followed expected patterns according to lymphoscintigraphic staging. Hybrid SPECT/CT lymphoscintigraphic classification showed strong positive correlation with clinical severity and TLS. Our results demonstrated substantial modification of lymphoscintigraphic staging by adding SPECT/CT to a conventional planar scintigraphy. In addition, a hybrid SPECT/CT is expected to provide new indicators reflecting lymphoscintigraphic staging and clinical severity by providing both of functional DBF and anatomical HP information.

Association between weight loss agents and elevated liver enzymes: a population-based cross-sectional study.

The widespread use of body weight control agents might be related to liver enzyme elevation, but this potential association has only been documented in a few case reports. This study aimed to investigate the associations between weight loss agents and elevated liver enzymes at the population-level. We conducted a cross-sectional study using Korea National Health and Nutrition Examination Survey (KNHANES) data from 2013 to 2019. This study included 36,259 participants over 20 years of age who completed the questionnaire and had no history of hepatitis, cancer, or renal failure. In these participants, we analyzed associations between weight loss agents and elevated liver enzymes by constructing multiple logistic regression models with adjustment for confounding factors and stratified by sex, age, and body mass index. The use of weight loss agents related to liver enzyme elevation in men (adjusted odds ratio (aOR): 1.36, 95% confidence interval (CI): 1.08-1.71) and participants aged less than 40 years (aOR: 1.44, 95% CI: 1.12-1.87). Using more types of weight loss agents was associated with liver enzyme elevation (aOR: 1.31, 95% CI: 1.03-1.67 for 1 weight loss agent, aOR: 1.93, 95% CI: 0.93-3.99 for ≥ 2 weight loss agents). Elevated liver enzymes were associated with the use of traditional medicines (aOR: 1.96, 95% CI: 1.14-3.34) and dietary supplements (aOR: 1.33, 95% CI: 1.02-1.72) in men. We observed an association between weight loss agents and liver enzyme elevation in men, particularly for traditional herbal medicines and dietary supplements. To confirm the observed associations, studies higher on the evidence hierarchy are needed.

In vivo tissue pharmacokinetics of ERBB2-specific binding oligonucleotide-based drugs by PET imaging.

Although aptamers have shown excellent target specificity in preclinical and clinical studies either by themselves or as aptamer-drug conjugates, their in vivo tissue pharmacokinetic (PK) analysis is still problematic. We aimed to examine the utility of image-based positron emission tomography (PET) to evaluate in vivo tissue PK, target specificity, and applicability of oligonucleotides. For this, fluorine-18-labeled aptamers with erb-b2 receptor tyrosine kinase 2 (ERBB2)-specific binding were synthesized by base-pair hybridization using a complementary oligonucleotide platform. To investigate the PKs and properties of in vivo tissue, usefulness of in vivo PET imaging in the development of an oligonucleotide-based drug as an assessment tool was evaluated in normal and tumor xenografted mice. ERBB2-cODN-idT-APs-[18 F]F ([18 F]1), injected intravenously showed significant and rapid uptake in most tissues except for the initial brain and muscle; the uptake was highest in the heart, followed by kidneys, liver, lungs, gall bladder, spleen, and stomach. The main route of excretion was through the renal tract ~77.8%, whereas about 8.3% was through the biliary tract of the total dose. The estimated effective dose for an adult woman was 0.00189 mGy/MBq, which might be safe. ERBB2-positive tumor could be well visualized in the KPL4 xenograft animal model by in vivo PET imaging. Consequently, the distribution in each organ including ERBB2 expression could be well determined and quantified by PET with fluorine-18-labeled aptamers. In vivo PK parameters such as terminal half-life, time to maximum concentration, area under the curve, and maximum concentration, were also successfully estimated. These results suggest that image-based PET with radioisotope-labeled aptamers could be provide valuable information on properties of oligonucleotide-based drugs in drug discovery of targeted therapeutics against various diseases.

Clinical Impact of SPECT/CT in Evaluation of Abdominothoracic Fistula.

ABSTRACT: Abdominothoracic fistula is rarely observed but can be life-threatening. Pleuroperitoneal communication, known to occur in 1.6% of all patients who undergo continuous ambulatory peritoneal dialysis, is an uncommon but well-recognized complication. The most common symptoms are dyspnea and right-sided pleural effusion. A biliopleural fistula is well-described as a complication of radiofrequency ablation and transcatheter arterial chemoembolization of hepatic lesions. It is important to diagnose the cause of pleural effusion early for proper treatment because if the abdominothoracic fistula effusion amount is not large, appropriate diagnosis may be difficult. Here, we introduce 2 cases showing the usefulness of SPECT/CT in evaluating pleuroperitoneal and biliopleural fistulas.

Association Between the Use of Tobacco Products and Food Insecurity Among South Korean Adults.

Objectives: Food insecurity is the most basic form of human deprivation; thus, strategies to eradicate poverty should include policies to improve food insecurity. This study investigated the association between the use of tobacco products and food insecurity. Methods: We analyzed 21,063 adults from the Korea National Health and Nutrition Examination Survey, 2013-2015, 2019. The OR and 95% CI for food insecurity was calculated in each category of the status of tobacco products use and sociodemographic characteristics using multivariable logistic regression analysis. Results: Of 21,063 participants, 7.3% belonged to the food insecurity group. The OR (95% CI) for food insecurity was 1.34 (1.08-1.65) among current users of any tobacco products compared with those who had never used any tobacco product. The odds for food insecurity were higher among those with secondhand smoke exposure, younger participants, those with lower household income, lower levels of education, manual workers or people without occupation, and separated/widowed/divorced participants. Conclusion: Use of any tobacco products was associated with food insecurity among South Korean adults. Tobacco control could improve food insecurity.

Gender Differences in Comorbidities and Attitudes Regarding Weight Control among Young Adults with Obesity in Korea.

INTRODUCTION: Obesity in young adulthood increases the risk for premature death, and the prevalence of obesity rapidly increasing among young adults, particularly in young men. We evaluated the gender differences in accompanying comorbidities and attitudes regarding weight control among young Korean adults with obesity. MATERIALS AND METHODS: We analyzed 2,050 young adults with obesity (1,325 men and 725 women) in the 7th KNHANES (2016-2018) aged 19-44 years, with body mass indexes (BMIs) ≥25.0 kg/m2. The odds ratios (ORs) and 95% confidence intervals (CIs) for poor lifestyle factors and accompanying illnesses as well as self-perceived weight status, weight control efforts, and weight control strategies in men compared to those in women were calculated by multivariate logistic regression analysis. RESULTS: The mean BMIs and waist circumferences were 28.2 ± 0.1 kg/m2 and 93.6 ± 0.2 cm and 28.6 ± 0.1 kg/m2 and 88.7 ± 0.4 cm, in men and women, respectively. The ORs and 95% CIs for abdominal obesity (1.52, 1.11-2.07), hypertension (3.11, 2.20-4.40), hypercholesterolemia (1.45, 1.09-1.93), hypertriglyceridemia (3.37, 2.38-4.78), and elevated alanine transaminase concentration (6.53, 4.56-9.36) were higher in young men compared to those in young women. Despite the higher prevalences of comorbid conditions, the odds of inappropriate weight perception (8.13, 4.17-15.86), lack of weight control efforts (2.20, 1.71-2.84), lack of diet therapy (1.56, 1.13-2.16), lack of pharmacotherapy (13.27, 6.82-25.79), heavy drinking (1.32, 1.02-1.72), current smoking (6.92, 5.00-9.59), and frequent eating out (4.38, 3.35-5.71) were higher among men. However, the odds of not engaging in exercise (0.48, 0.35-0.64) were lower among men compared to that in women. DISCUSSION: Despite their higher prevalences of comorbidities, appropriate weight perception and weight control efforts are insufficient in young men with obesity. These gender differences should be considered to provide tailored programs for weight reduction in young adults with obesity.

Clinical Usefulness of 18 F-FET PET in a Pediatric Patient With Suspected Demyelinating Disease.

ABSTRACT: An 11-year-old boy who presented with headache and progressive right-sided weakness exhibited cortical swelling in the parafalcine area of both frontoparietal high convexity and splenium portion of corpus callosum on brain MRI. This suggested the possibility of encephalopathy, but required differential diagnosis from brain tumor. 18 F-FET ( O -(2-[ 18 F]fluoroethyl)- l -tyrosine) PET/CT identified increased uptake along the parafalcine area of the frontoparietal lobes and the splenium portion of the corpus callosum. The relatively low target-to-background ratios were more indicative of inflammatory changes such as demyelinating disease. The patient recovered after empirical steroid and immunoglobulin treatment. Clinically, the patient was diagnosed with acute disseminated encephalomyelitis.

Prevalence and risk factors of maternal depression among women who participated in a home visitation program in South Korea.

PURPOSE: The psychosocial health of mother is crucial for healthy prenatal period and early childhood. We investigated the prevalence and risk factors of maternal depression during pregnancy and postpartum among women who participated in a home visitation program in Seoul, South Korea (Seoul Healthy First Step Project, SHFSP). METHODS: We analyzed 80,116 women who participated in the SHFSP, which was launched by Seoul metropolitan government in 2013, and defined peripartum depression as a score ≥ 10 on the Korean version of the Edinburgh Postnatal Depression Scale (EPDS). Sociodemographic factors and psychosocial health status were evaluated through a standardized questionnaire completed by participants upon program registration. We calculated the prevalence of women at risk for peripartum depression and evaluated associated factors by multivariable logistic regression analysis. RESULTS: Prevalence of women at risk for peripartum depression was 17.7% (prepartum depression: 14.2%, postpartum depression: 24.3%). Younger maternal age, low income (OR 2.40, 95% CI 2.03-2.84), disability (2.61, 1.96-3.47), single parenthood (3.27, 2.69-3.99), and smoking (2.02, 1.44-2.83) increased the peripartum depression risk. Furthermore, experience of stress, change, or loss over the past 12 months (3.36, 3.22-3.50), history of treatment for emotional issues (2.47, 2.27-2.70), experience of child abuse (1.91, 1.74-2.11), and domestic violence (2.25, 1.81-2.80) increased the risk for peripartum depression, whereas having helpers for the baby (0.62, 0.58-0.67), having someone to talk with (0.31, 0.27-0.35), and considering oneself confident (0.30, 0.29-0.31) decreased the risk. CONCLUSIONS: Policies to reduce and manage peripartum depression should be strengthened, with a focus on high-risk pregnant and puerperal women.

Relationships between fasting glucose levels, lifestyle factors, and metabolic parameters in Korean adults without diagnosis of diabetes mellitus.

BACKGROUND: We investigated the associations between fasting glucose level ranges with lifestyle factors and metabolic profiles among adults without previous diagnosis of diabetes. METHODS: We analyzed 13 625 adults without previous diagnosis of diabetes from the Korea National Health and Nutrition Examination Survey during 2016 to 2018. We categorized fasting glucose levels (mg/dl) as follows: <90, 90 to 99, 100 to 109, 110 to 124, and ≥125. We evaluated trends in the proportions of individuals with obesity, abdominal, obesity, current smoking, heavy drinking, and low physical activity according to these categories, and the odds for uncontrolled blood pressure (BP), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and high-density lipoprotein cholesterol (HDL-C) for each fasting glucose level compared to a fasting glucose level of <90 mg/dl. RESULTS: The proportions of individuals with obesity, abdominal obesity, and heavy drinking increased according to fasting glucose level (P for trend <.05). The odds for BP ≥140/90 mm Hg, TG ≥150 mg/dl, HDL-C < 40 mg/dl in men, and HDL-C < 50 mg/dl in women increased with increasing fasting glucose levels; however, the odds for LDL-C ≥ 130 mg/dl increased with increasing fasting glucose levels only in women. The increases in odds for uncontrolled BP and lipid profiles were mostly observed for fasting glucose levels ≥90 mg/dl. CONCLUSIONS: Efforts are needed to prevent increased fasting glucose levels, as higher levels, even within normal range, were associated with poor metabolic profiles.

Extracellular Vesicles Induce an Aggressive Phenotype in Luminal Breast Cancer Cells Via PKM2 Phosphorylation.

BACKGROUND: Aerobic glycolysis is a hallmark of glucose metabolism in cancer. Previous studies have suggested that cancer cell-derived extracellular vesicles (EVs) can modulate glucose metabolism in adjacent cells and promote disease progression. We hypothesized that EVs originating from cancer cells can modulate glucose metabolism in recipient cancer cells to induce cell proliferation and an aggressive cancer phenotype. METHODS: Two breast cancer cell lines with different levels of glycolytic activity, MDA-MB-231 cells of the claudin-low subtype and MCF7 cells of the luminal type, were selected and cocultured as the originating and recipient cells, respectively, using an indirect coculture system, such as a Transwell system or a microfluidic system. The [18F]fluorodeoxyglucose (FDG) uptake by the recipient MCF7 cells was assessed before and after coculture with MDA-MB-231 cells. Proteomic and transcriptomic analyses were performed to investigate the changes in gene expression patterns in the recipient MCF7 cells and MDA-MB-231 cell-derived EVs. RESULTS: FDG uptake by the recipient MCF7 cells significantly increased after coculture with MDA-MB-231 cells. In addition, phosphorylation of PKM2 at tyrosine-105 and serine-37, which is necessary for tumorigenesis and aerobic glycolysis, was highly activated in cocultured MCF7 cells. Proteomic profiling revealed the proliferation and dedifferentiation of MCF7 cells following coculture with MDA-MB-231 cells. Transcriptomic analysis demonstrated an increase in glycolysis in cocultured MCF7 cells, and the component analysis of glycolysis-related genes revealed that the second most abundant component after the cytoplasm was extracellular exosomes. In addition, proteomic analysis of EVs showed that the key proteins capable of phosphorylating PKM2 were present as cargo inside MDA-MB-231 cell-derived EVs. CONCLUSIONS: The phenomena observed in this study suggest that cancer cells can induce a phenotype transition of other subtypes to an aggressive phenotype to consequently activate glucose metabolism via EVs. Therefore, this study could serve as a cornerstone for further research on interactions between cancer cells.

18F-FET PET/CT as a Diagnostic Tool for Brain Abscess.

ABSTRACT: A 49-year-old man presented with sudden right-sided weakness and seizure. Brain MRI identified a lobulated mass with diffusion restriction and irregular wall enhancement in the left parietal lobe. 18F-FET (O-(2-[18F]fluoroethyl)-l-tyrosine) PET/CT was performed, which identified a cystic mass in the left parietal lobe accompanied by FET uptake. Compartmentalized uptake was also confirmed throughout the left parietal lobe. Considering the relatively low target-to-background ratio and uptake observed in the entire left parietal lobe, the lesion was more likely to be a brain abscess than a tumor. The pathologic diagnosis after mass removal was acute and chronic inflammation with abscess.

Lymphoscintigraphic Findings as Indicators of Lymphaticovenous Anastomosis Outcome in Patients With Extremity Lymphedema: A Retrospective Cohort Study.

PURPOSE: This study was performed to evaluate the usefulness of lymphoscintigraphy in predicting the surgical outcomes of lymphaticovenous anastomosis (LVA) in a patient with extremity lymphedema. PATIENTS AND METHODS: We retrospectively evaluated 133 patients with extremity lymphedema who underwent lymphoscintigraphy followed by LVA surgery from February 2018 to March 2020. Lymphoscintigraphic findings were evaluated on the following parameters: the extent of dermal backflow (small/large), lymphatic flow patterns (trunk flow pattern/proximal-restricted pattern/distal-restricted pattern), visualization of lymph nodes, and collateral lymphatic vessels. The mean circumferential difference change before and after surgery, circumferential reduction (CR) rate (%), was used as the clinical outcome variables. RESULTS: A decrease in circumference was observed in 93 (69.9%) of 133 patients after LVA. The extent of dermal backflow and lymphatic flow patterns was significantly correlated with improved clinical outcomes after LVA. The large extent of the dermal backflow group showed a more significant CR rate than the small extent (19.27% vs 1.24%, P = 0.005). The TP group showed the most significantly decreased CR rate to 21.46%, and the proximal-restricted pattern and distal-restricted pattern groups were -2.49% and -5.33%, respectively (P < 0.001). Multivariate analysis revealed that dermal backflow and lymphatic flow patterns were independent predictors of therapeutic outcome (P < 0.001). CONCLUSIONS: Our study demonstrates that pretreatment lymphoscintigraphy may help predict the therapeutic effect of LVA in patients with extremity lymphedema. Furthermore, dermal backflow and lymphatic flow patterns are independent predictors of CR rate after LVA surgery for extremity lymphedema.

Radioactive Iodine Treatment for Children and Young Adults with Thyroid Cancer in South Korea: A Population-based Study.

PURPOSE: This study investigated radioactive iodine treatment (RAIT) patterns and the secondary cancer incidence among children and young adults receiving RAIT after thyroidectomy for thyroid cancer. METHODS: This population-based cohort study used the Health Insurance Review and Assessment database of South Korea to identify a total of 18 617 children and young adults (0-29 years) who underwent thyroidectomy for thyroid cancer between 2008 and 2018. We recorded age at surgery, sex, the interval from surgery to RAIT, the doses of RAI, the number of RAIT sessions, and secondary cancer incidence. RESULTS: A total of 9548 (51.3%) children and young adults underwent 1 or more RAIT sessions. The initial dose of RAIT was 4.35 ±â€…2.19 GBq. The overall RAIT frequency fell from 60.9% to 38.5%, and the frequency of high-dose RAIT (>3.7 GBq) fell from 64.2% to 36.5% during the observational period. A total of 124 cases of secondary cancer developed during 120 474 person-years of follow-up; 43 (0.5%) in the surgery cohort and 81 (0.8%) in the RAIT cohort. Thus, the RAIT cohort was at an increased risk of secondary cancer (adjusted hazard ratio 1.52 [95% confidence interval 1.03-2.24], P = 0.035). CONCLUSION: The proportion of children and young adults receiving RAIT, and the RAI dose, fell significantly over the observational period. RAIT was associated with secondary cancers. This is of major concern in the context of child and young adult thyroid cancer survivors.

Trends in the Socioeconomic Inequalities Related to Second-Hand Smoke Exposure as Verified by Urine Cotinine Levels Among Nonsmoking Adults: Korea National Health and Nutrition Examination Survey 2008-2018.

INTRODUCTION: The expansion of smoke-free policies has reduced the prevalence of second-hand smoke (SHS) exposure; however, declines differ according to socioeconomic positions. We evaluated the trends in socioeconomic inequalities related to SHS exposure in nonsmoking Korean adults from 2008 to 2018. METHODS: We analyzed 30,027 nonsmoking adults from the Korea National Health and Nutrition Examination Survey 2008 to 2018. We evaluated trends in urine cotinine levels, self-reported prevalence of SHS exposure at workplaces and homes, and people exhibiting nonmeasurable urine cotinine levels between 2008 and 2018. To evaluate the yearly decline differences of urine cotinine levels according to socioeconomic positions, we calculated the interaction effects of year and education, household incomes, and occupation from linear regression analysis. RESULTS: In the last 11 years, the geometric means of urine cotinine levels decreased from 3.53 (95% CI 2.96-4.19) ng/mL to 0.60 (0.57-0.64) ng/mL in males, and from 2.36 (2.03-2.73) ng/mL to 0.53 (0.51-0.56) ng/mL in females. The prevalence of SHS exposure at workplaces and homes also declined. In the multivariate model, the interaction effects between education and years were significant; therefore, indicating a substantial yearly decline of urine cotinine levels in higher educated individuals. The interaction effects between household incomes and years were only significant among males; the interaction effects between occupations and years were not significant. CONCLUSIONS: SHS exposure in nonsmoking Korean adults has consistently decreased; however, socioeconomic inequalities related to SHS exposure by education level have widened. Policies targeting socioeconomically disadvantaged populations should be implemented to decrease the disparities of SHS exposure. IMPLICATIONS: Along with tobacco control policies, the prevalence of self-reported and urinary cotinine verified SHS exposure has decreased in the last 11 years. In contrast, the socioeconomic inequalities related to SHS exposure by education level have increased over time. This study emphasizes the need for implementing tobacco control policies to reduce disparities of SHS exposure.

The impact of data-driven respiratory gating in clinical F-18 FDG PET/CT: comparison of free breathing and deep-expiration breath-hold CT protocol.

BACKGROUND: Respiratory motion can diminish PET image quality and lead to inaccurate lesion quantifications. Data-driven gating (DDG) was recently introduced as an effective respiratory gating technique for PET. In the current study, we investigated the clinical impact of DDG on respiratory movement in 18F-FDG PET/CT. METHOD: PET list-mode data were collected for each subject and DDG software was utilized for extracting respiratory waveforms. PET images was reconstructed using Q.clear and Q.clear + DDG, respectively. We evaluated SUVmax, SUVmean, the coefficient of variance (CoV), metabolic tumor volume (MTV), and tumor heterogeneity using the area under the curve of cumulative SUV histogram (AUC-CSH). Metabolic parameter changes were compared between each reconstruction method. The Deep-Expiration Breath Hold (DEBH) protocol was introduced for CT scans to correct spatial misalignment between PET and CT and compared with conventional free breathing. The DEBH and free breathing (FB) protocol comparison was made in a separate matching cohort using propensity core matching rather than the same patient. RESULTS: Total 147 PET/CT scans with excessive respiratory movements were used to study DDG-mediated correction. After DDG application, SUVmax (P < 0.0001; 8.15 ± 4.77 vs. 9.03 ± 5.02) and SUVmean (P < 0.0001; 4.91 ± 2.44 vs. 5.49 ± 2.68) of lung and upper abdomen lesions increased, while MTV significantly decreased (P < 0.0001; 7.07 ± 15.46 vs. 6.58 ± 15.14). In addition, the percent change of SUVs was greater in lower lung lesions compared to upper lobe lesions. Likewise, the MTV reduction was significantly greater in lower lobe lesions. No significant difference dependent on location was observed in liver lesions. DEBH-mediated CT breathing correction did not make a significant difference in lesion metabolic parameters compared to conventional free breathing. CONCLUSIONS: These results suggest that DDG correction enables more corrected quantification from respiratory movements for lesions located in the lung and upper abdomen. Therefore, we suggest that DDG is worth using as a standard protocol during 18F-FDG PET/CT imaging.

Prospective evaluation of metabolic intratumoral heterogeneity in patients with advanced gastric cancer receiving palliative chemotherapy.

Although metabolic intratumoral heterogeneity (ITH) gives important value on treatment responses and prognoses, its association with treatment outcomes have not been reported in gastric cancer (GC). We aimed to evaluate temporal changes in metabolic ITH and the associations with treatment responses, progression-free survival (PFS), and overall survival (OS) in advanced GC patients. Eighty-five patients with unresectable, locally advanced, or metastatic GC were prospectively enrolled before the first-line palliative chemotherapy and underwent [18F]FDG PET at baseline (TP1) and the first response follow-up evaluation (TP2). Standardized uptake values (SUVs), volumetric parameters, and textural features were evaluated in primary gastric tumor at TP1 and TP2. Of 85 patients, 44 had partial response, 33 had stable disease, and 8 progressed. From TP1 to TP2, metabolic ITH was significantly reduced (P < 0.01), and the degree of the decrease was greater in responders than in non-responders (P < 0.01). Using multiple Cox regression analyses, a low SUVmax at TP2, a high kurtosis at TP2 and larger decreases in the coefficient of variance were associated with better PFS. A low SUVmax at TP2, larger decreases in the metabolic tumor volume and larger decreased in the energy were associated with better OS. Age older than 60 years and responders also showed better OS. An early reduction in metabolic ITH is useful to predict treatment outcomes in advanced GC patients.