Muscle Radiodensity Research Articles

Tumor metabolic activity is associated with subcutaneous adipose tissue radiodensity and survival in non-small cell lung cancer

BackgroundCachexia-associated body composition alterations and tumor metabolic activity are both associated with survival of cancer patients. Recently, subcutaneous adipose tissue properties have emerged as particularly prognostic body composition features. We hypothesized that tumors with higher metabolic activity instigate cachexia related peripheral metabolic alterations, and investigated whether tumor metabolic activity is associated with body composition and survival in patients with non-small cell lung cancer (NSCLC), focusing on subcutaneous adipose tissue. MethodsA retrospective analysis was performed on a cohort of 173 patients with NSCLC. 18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) scans obtained before treatment were used to analyze tumor metabolic activity (standardized uptake value (SUV) and SUV normalized by lean body mass (SUL)) as well as body composition variables (subcutaneous and visceral adipose tissue radiodensity (SAT /VAT radiodensity) and area; skeletal muscle radiodensity (SM radiodensity) and area). Subjects were divided into groups with high or low SAT radiodensity based on Youden Index of Receiver Operator Characteristics (ROC). Associations between tumor metabolic activity, body composition variables, and survival were analyzed by Mann-Whitney tests, Cox regression, and Kaplan-Meier analysis. ResultsThe overall prevalence of high SAT radiodensity was 50.9% (88/173). Patients with high SAT radiodensity had shorter survival compared with patients with low SAT radiodensity (mean: 45.3 vs. 50.5 months, p=0.026). High SAT radiodensity was independently associated with shorter overall survival (multivariate Cox regression HR=1.061, 95% CI: 1.022-1.101, p=0.002). SAT radiodensity also correlated with tumor metabolic activity (SULpeak rs=0.421, p=0.029; SUVpeak rs=0.370, p=0.048). In contrast, the cross-sectional areas of SM, SAT, and VAT were not associated with tumor metabolic activity or survival. ConclusionHigher SAT radiodensity is associated with higher tumor metabolic activity and shorter survival in patients with NSCLC. This may suggest that tumors with higher metabolic activity induce subcutaneous adipose tissue alterations such as decreased lipid density, increased fibrosis, or browning.

Strength-to-muscle radiodensity: A potential new index for muscle quality

Background & aimsAlthough it is widely recognized that muscle quality significantly influences adverse outcomes in patients with cancer, the precise definition of muscle quality remains elusive. The muscle quality index (MQI), also known as muscle-specific strength, is a relatively recent functional concept of muscle quality. It is obtained through the ratio of muscle strength to muscle mass, but its predictive value in patients with cancer remains unknown. In this study, we explored the prognostic significance of MQI in patients with cancer. Furthermore, we introduce and assess the prognostic potential of a novel muscle quality metric: the strength-to-muscle-radiodensity index (SMRi). MethodsA secondary analysis was conducted on a prospective cohort study. CT scans were opportunistically used to assess body composition parameters, including skeletal muscle mass (SM in cm2) and muscle radiodensity (SMD in HU) at the third lumbar vertebra (L3). Handgrip strength (HGS) was measured. MQICT was calculated using the ratio of HGS to SM (cm2). SMRi was calculated as the ratio of HGS to SMD (HU). For analysis purposes, low MQICT and SMRi was defined using two approaches: statistical cutoffs associated with survival, and median-based distribution data. ResultsA total of 250 patients were included (52.8% females, 52% adults, 20-90 years). Gastrointestinal tumors and stage III-IV were the most frequent diagnosis and stages. SMRi and MQICT were strongly positively correlated (ρ = 0.71 P < .001). Individual components of MQICT and SMRi were also positively correlated. Patients with both low MQICT and SMRi had shorter survival (log-rank P = .023 and P = .003, respectively). When applying median distribution cutoffs, SMRi emerged as the most accurate predictor of mortality (HR adjusted 3.18, 95% CI 1.50 to 6.75, C-index: 0.71), when compared to MQICT (HR adjusted 1.49, 95% CI 0.77 to 2.87, C-index: 0.68). ConclusionThis study introduces the concept and potential prognostic significance of the SMRi. The physiological and clinical implications of this new index warrant further investigation across a spectrum of diseases, including cancer.

Dual-Energy CT muscle fat fraction as a new imaging biomarker of body composition and survival predictor in critically ill patients

ObjectiveTo analyze changes in the muscular fat fraction (FF) during immobilization at the intensive care unit (ICU) using dual-energy CT (DECT) and evaluate the predictive value of the DECT FF as a new imaging biomarker for morbidity and survival.MethodsImmobilized ICU patients (n = 81, 43.2% female, 60.3 ± 12.7 years) were included, who received two dual-source DECT scans (CT1, CT2) within a minimum interval of 10 days between 11/2019 and 09/2022. The DECT FF was quantified for the posterior paraspinal muscle by two radiologists using material decomposition. The skeletal muscle index (SMI), muscle radiodensity attenuation (MRA), subcutaneous-/ visceral adipose tissue area (SAT, VAT), and waist circumference (WC) were assessed. Reasons for ICU admission, clinical scoring systems, therapeutic regimes, and in-hospital mortality were noted. Linear mixed models, Cox regression, and intraclass correlation coefficients were employed.ResultsBetween CT1 and CT2 (median 21 days), the DECT FF increased (from 20.9% ± 12.0 to 27.0% ± 12.0, p = 0.001). The SMI decreased (35.7 cm2/m2 ± 8.8 to 31.1 cm2/m2 ± 7.6, p < 0.001) as did the MRA (29 HU ± 10 to 26 HU ± 11, p = 0.009). WC, SAT, and VAT did not change. In-hospital mortality was 61.5%. In multivariable analyses, only the change in DECT FF was associated with in-hospital mortality (hazard ratio (HR) 9.20 [1.78–47.71], p = 0.008), renal replacement therapy (HR 48.67 [9.18–258.09], p < 0.001), and tracheotomy at ICU (HR 37.22 [5.66–245.02], p < 0.001). Inter-observer reproducibility of DECT FF measurements was excellent (CT1: 0.98 [0.97; 0.99], CT2: 0.99 [0.96–0.99]).ConclusionThe DECT FF appears to be suitable for detecting increasing myosteatosis. It seems to have predictive value as a new imaging biomarker for ICU patients.Clinical relevance statementThe dual-energy CT muscular fat fraction appears to be a robust imaging biomarker to detect and monitor myosteatosis. It has potential for prognosticating, risk stratifying, and thereby guiding therapeutic nutritional regimes and physiotherapy in critically ill patients.Key PointsThe dual-energy CT muscular fat fraction detects increasing myosteatosis caused by immobilization.Change in dual-energy CT muscular fat fraction was a predictor of in-hospital morbidity and mortality.Dual-energy CT muscular fat fraction had a predictive value superior to established CT body composition parameters.

Assessment of myosteatosis and functionality in pretreatment gynecological cancer patients.

We aimed to investigate the relationship between pretreatment gynecologic cancer survival and the physical function of patients with myosteatosis. Understanding this relationship prior to treatment would help healthcare providers identify and refer patients with poor muscle quality to an exercise program prior to treatment. We conducted a cross-sectional analysis of 73 GC patients. Physical function was quantified using handgrip strength and an adapted version of the Senior Fitness Test (aerobic endurance not included). The EORTC QLC-C30 was used to evaluate general health quality. Myosteatosis (values below the median muscle radiodensity), muscle mass, and adipose tissue variables were calculated from the computed tomography (CT) scan at the third lumbar vertebra using specific software. Seventy patients (50.9 ± 15.2) were included; 41.5% had stage III or IV disease, and 61.4% had cervical cancer. The myosteatosis group was 11.9years older and showed reduced functioning compared to the normal-radiodensity group. Age and Timed Up and Go (TUG) test results were shown to be the most reliable predictors of muscle radiodensity in pretreatment gynecological patients according to multivariate regression analysis (R2 = 0.314). Gynecological healthcare professionals should be aware that prompt exercise programs might be especially beneficial for older patients with reduced TUG performance to preserve muscle function and quality.

Dialysis Duration, Time Interaction, and Visceral Fat Accumulation: A 6-Year Posttransplantation Study.

Kidney transplantation (KT) leads to body composition change, particularly increasing the fat mass. However, limited researches have focused on the long-term follow-up of these changes and factors influencing body composition after KT. This study evaluated body composition in 31 adult KT recipients, measuring body mass index (BMI), the psoas muscle mass index (PMI) representing muscle mass, visceral and subcutaneous adipose tissue (VAT and SAT) representing fat mass, and skeletal muscle radiodensity (SMR) representing muscle quality before KT and at 2, 4, and 6years posttransplantation using computed tomography. Linear mixed models (LMM) analyzed temporal changes and contributing factors, while growth curve models assessed influence of these factors on body composition changes posttransplantation. Following KT, BMI, and PMI remained stable, while SAT increased significantly, revealing a 1.30-fold increase from baseline 2years after transplantation. Similarly, a substantial increase in VAT was observed, with a 1.47-fold increase from baseline 2years after transplantation with a further 1.75-fold increase 6years after transplantation. In contrast, SMR decreased with a 0.86-fold decrease from baseline after 2years. VAT increase was significantly influenced by the interaction between posttransplantation and dialysis duration. Growth curve models confirmed this interaction effect persistently influenced VAT increase posttransplantation. The study revealed that KT promoted significant alterations in body composition characterized by increase in the VAT and SAT and a decline in SMR. Notably, dialysis duration and its interaction with posttransplantation duration emerged as significant factors influencing VAT increase.

Albumin-myosteatosis gauge as a prognostic factor in patients with advanced pancreatic cancer undergoing first-line chemotherapy.

Sarcopenia and myosteatosis have been associated with a poor prognosis for several cancers. The albumin-myosteatosis gauge (AMG) is a novel integrated measure proposed to assess myosteatosis along with serum albumin level as a surrogate of systemic inflammation and malnutrition. The aim of this study was to investigate the prognostic value of AMG in patients with advanced pancreatic ductal adenocarcinoma (PDAC). Patients with advanced PDAC treated with chemotherapy between 2013 and 2022 were evaluated. Skeletal muscle radiodensity (SMD) and skeletal muscle index (SMI) were calculated using computed tomography at the level of the L3 vertebra. The AMG was defined as albumin x SMD and expressed as an arbitrary unit (AU). Patients were first categorized by sex-specific quartiles and then dichotomized at the sex-specific median value of the AMG. A total of 196 patients were included. The median age (interquartile range) was 62 (54-67), and 128 (65.3%) were male. With regard to AMG, 142.86 and 114.15 AU were identified as cutoff values for males and females, respectively. In multivariable analyses, lower AMG values (G1-G2 vs. G3-G4) (HR: 1.61, 95% CI 1.17-2.21, p = 0.003), higher ECOG performance score (> 0 vs. 0) (HR: 1.51, 95% CI 1.10-2.06, p = 0.009) and metastatic disease (vs. locally advanced) (HR: 1.88, 95% CI 1.27-2.79, p = 0.001) were associated with OS. The study findings suggest the prognostic value of AMG in patients with advanced PDAC undergoing first-line chemotherapy. Further studies are warranted to validate these findings and assess potential predictive role of AMG in guiding treatment selection.

Racial differences in body composition and survival among older adults with gastrointestinal malignancies

IntroductionMuscle and adipose tissue measures can be quantified from routinely obtained computed tomography (CT) images and are predictors of chemotherapy-related toxicities and survival among patients with gastrointestinal (GI) malignancies. Most studies to date have consisted of predominantly White patients, and the role of body composition among minoritized racial groups is unknown. We examined racial differences in body composition and survival among patients with GI malignancies. Materials and MethodsThis was a prospective cohort study of patients with GI malignancies. Single slices of axial CT images from L3 segments were analyzed using Slice-O-Matic software. The skeletal muscle area (cm2) was divided by height to obtain the skeletal muscle index (SMI, cm2/m2). Skeletal muscle radiodensity (SMD) in Hounsfield units (HU) was used for muscle composition. We compared body composition parameters between non-Hispanic (NH)-White and NH-Black participants. Cox models were used to examine the impact of body composition on survival. We proposed new race-specific cutoffs for body composition using optimal stratification. ResultsFive hundred forty patients were included, of which 24% were NH-Black. In Cox models stratified by race, each 5 cm2/m2 decrease in SMI was associated with increase in risk of all-cause mortality in NH-Black patients (hazard ratio [HR] 1.25; 95% confidence interval [CI] 1.04–1.49 p = 0.02). With the existing cut points, neither sarcopenia nor myosteatosis was associated with worse survival. Using a new cutoff for sarcopenia in NH-Black patients, NH-Black patients with sarcopenia (HR 2.31 95%CI 1.10–4.88 p = 0.03) and myosteatosis (HR 2.63 95% CI 1.25–5.53 p = 0.01) had worse survival. DiscussionNH-Black older patients with GI cancers and sarcopenia or myosteatosis have worse overall survival.

Metabolic score tool for personalized acute pancreatitis prognosis: A multicenter analysis.

Increasing evidence suggests that body composition is associated with the development of acute pancreatitis (AP). This study aimed to investigate the applicability of body composition in predicting AP severity. Data of 213 patients with AP from Affiliated Hospital of Putian University (AHOPTU) were included in this study, whilst data of 173 patients with AP from Fujian Medical University Union Hospital (FMUUH) were used for external validation. Patients were classified into the non-severe and severe groups according to AP severity. After seven days of treatment, in patients from AHOPTU, the difference in skeletal muscle index before and after treatment (ΔSMI) was significantly higher (P = 0.002), while the skeletal muscle radiodensity before treatment (PreSMR) was significantly lower (P = 0.042) in the non-severe group than in the severe group. The multivariate logistic regression model also revealed that the ΔSMI and PreSMR were independent risk factors for AP severity. The optimal cut-off values of ΔSMI and PreSMR were 1.0 and 43.7, respectively. The following metabolic score (SMS) was established to predict AP severity: 0: ΔSMI < 1.0 and PreSMR < 43.7; 1: ΔSMI ≥ 1.0 and PreSMR < 43.7 or ΔSMI < 1.0 and PreSMR ≥ 43.7; 3: ΔSMI ≥ 1.0 and PreSMR ≥ 43.7. In patients from AHOPTU and FMUUH, the areas under the curves (AUC) for this model were 0.764 and 0.741, respectively. ΔSMI and PreSMR can accurately predict AP severity. It is recommended to routinely evaluate the statuses of patients with AP using the predictive model presented in this study for individualized treatment.

Low skeletal muscle radiodensity is a risk factor for adjuvant chemotherapy discontinuation in colorectal cancer.

Previously, we reported SMR (skeletal muscle radiodensity) as a potential prognostic marker for colorectal cancer. However, there have been limited studies on the association between SMR and the continuation of adjuvant chemotherapy in colorectal cancer. In this retrospective study, 143 colorectal cancer patients underwent curative surgery and adjuvant chemotherapy using the CAPOX regimen. Patients' SMRs were measured from preoperative CT images and divided into low (bottom quarter) and high (top three quarters) SMR groups. We compared chemotherapy cycles, capecitabine and oxaliplatin doses, and adverse effects in each group. The low SMR group had significantly fewer patients completing adjuvant chemotherapy compared to the high SMR group (44% vs. 68%, P < 0.01). Capecitabine and oxaliplatin doses were also lower in the low SMR group. Incidences of Grade 2 or Grade 3 adverse effects did not differ between groups, but treatment discontinuation due to adverse effects was significantly higher in the low SMR group. Logistic regression analysis revealed Stage III disease (odds ratio 18.09, 95% CI 1.41-231.55) and low SMR (odds ratio 3.26, 95% CI 1.11-9.56) as factors associated with unsuccessful treatment completion. Additionally, a higher proportion of low SMR patients received fewer than 2 cycles of chemotherapy (50% vs. 12%). The low SMR group showed higher treatment incompletion rates and received lower drug doses during adjuvant chemotherapy. Low SMR independently contributed to treatment non-completion in colorectal cancer patients.

Skeletal muscle and visceral adipose radiodensities are pre-surgical, non-invasive markers of aggressive kidney cancer.

Most studies on body composition in kidney cancer have been conducted among patients with metastatic disease. Given that aggressive tumours can adversely impact body composition and even non-metastatic tumours can be aggressive, we evaluated associations between pre-surgical body composition features and tumour pathological features in patients with non-metastatic clear cell renal cell cancer (ccRCC). The Resolve Cohort consists of 1239 patients with non-metastatic ccRCC who underwent nephrectomy at Memorial Sloan Kettering Cancer Center between 2000 and 2020. The cross-sectional areas and radiodensities of skeletal muscle, visceral adipose, and subcutaneous adipose tissues were determined from pre-surgical computed tomography (CT) scans at the third lumbar vertebrae using Automatica software. Pearson's correlation coefficients describe inter-relationships among BMI and body composition variables, while odds ratios (OR) and 95% confidence intervals (CI) estimate associations between continuous body composition features (per 1-standard deviation) and advanced stage (Stage III vs. Stages I-II) and high Fuhrman grade (Grades 3-4 vs. 1-2) from multivariable logistic regression models that considered the potential impact of biological sex, contrast enhanced CTs, and early age at onset of ccRCC. The cohort was predominantly male (69%), white (89%), and had a median age of 58. The proportion of patients presenting with advanced stage and high-grade disease were 31% and 51%, respectively. In models that adjusted for demographics and all body composition variables simultaneously, decreasing skeletal muscle radiodensity (i.e., more fat infiltration) but increasing visceral adipose tissue radiodensity (i.e., more lipid depletion) were associated with advanced tumour features. Per 8.4 HU decrease in skeletal muscle radiodensity, the odds of presenting with advanced stage was 1.61 (95% CI: 1.34-1.93). Per 7.22 HU increase in visceral adipose tissue radiodensity, the odds of presenting with advanced stage was 1.45 (95% CI: 1.22-1.74). Skeletal muscle index (i.e., sarcopenia) was not associated with either tumour feature. Similar associations were observed for Fuhrman grade, a more direct marker of tumour aggressiveness. Associations did not differ by sex, contrast use, or age at onset of ccRCC. Lipid infiltrated skeletal muscle, but lipid depleted visceral adipose tissue were independently associated with advanced tumour features in non-metastatic ccRCC. Findings highlight the importance of evaluating the full range of body composition features simultaneously in multivariable models. Interpreting pre-surgical CTs for body composition for patients may be a novel and non-invasive way to identify patients with aggressive renal tumours, which is clinically relevant as renal biopsies are not routinely performed.

Association of excess visceral fat and severe illness in hospitalized COVID-19 patients in Japan: a retrospective cohort study.

Obesity, defined by body mass index (BMI), is a well-known risk factor for the severity of coronavirus disease 2019 (COVID-19). Adipose tissue distribution has also been implicated as an important factor in the body's response to infection, and excess visceral fat (VF), which is prevalent in Japanese, may contribute significantly to the severity. Therefore, this study aimed to evaluate the association of obesity and VF with COVID-19 severe illness in Japan. This retrospective cohort study involved 550 COVID-19 patients admitted to a tertiary care hospital with BMI and body composition data, including VF. The primary endpoint was severe illness, including death, due to COVID-19 during hospitalization. Logistic regression analysis was applied to examine the quartiles of BMI and VF on severe illness after adjusting for covariates such as age, sex, subcutaneous fat, paraspinal muscle radiodensity, and comorbidities affecting VF (COPD, cancer within 5 years, immunosuppressive agent use). The median age was 56.0 years; 71.8% were males. During hospitalization, 82 (14.9%) experienced COVID-19 severe illness. In the multivariate logistic regression analysis, Q4 of BMI was not significantly associated with severe illness compared to Q1 of BMI (OR 1.03; 95% CI 0.37-2.86; p = 0.95). Conversely, Q3 and Q4 of VF showed a higher risk for severe illness compared to Q1 of VF (OR 2.68; 95% CI 1.01-7.11; p = 0.04, OR 3.66; 95% CI 1.30-10.26; p = 0.01, respectively). Stratified analysis by BMI and adjusted for covariates showed the positive association of VF with severe illness only in the BMI < 25 kg/m2 group. High BMI was not an independent risk factor for COVID-19 severe illness in hospitalized patients in Japan, whereas excess VF significantly influenced severe illness, especially in patients with a BMI < 25 kg/m2.

Factors associated with variability in skeletal muscle radiodensity in patients with metastatic cancer

ObjectivesThis study aimed to explore factors associated with skeletal muscle radiodensity (SMD) variability in patients with metastatic cancer. MethodsThis study included 393 patients (median age 61 y, 70% women) who had computed tomography (CT) scans within 30 days of inclusion in the study. SMD was evaluated from CT by averaging the Hounsfield unit value of the total muscle area. Skeletal muscle index (SMI), visceral adipose tissue index (VATI), subcutaneous adipose tissue index (SATI), and total adipose tissue index (TATI) were also assessed by CT. Additionally, age, sex, race/skin color, disease characteristics, comorbidities, inflammatory markers, handgrip strength (HGS), and body mass index (BMI) were recorded and evaluated in the linear regression analysis to identify factors associated with SMD variability. ResultsMultivariate explanatory models having SMD as an independent variable were performed and included BMI (model 1, r2 = 0.699), TATI (model 2, r2 = 0.712) or VATI and SATI (model 3, r2 = 0.706) in addition to age, race/skin color, tumor site, kidney disease, serum albumin, HGS, and SMI as dependent variables. For all models, lower SMD was associated with higher age, BMI, and adiposity measurements, kidney disease, White race/skin color, and lower serum albumin, HGS, and SMI. The primary tumor site also contributed to changes in SMD in all models, specifically those located in the gastrointestinal tract, gynecologic, and bone and connective tissue. Conclusion: In this group of patients with metastatic cancer, lower SMD was associated with older age, White race/skin color, and an overall worse clinical condition.

Muscle and fat composition in patients with newly diagnosed multiple myeloma

Measures of muscle and adipose tissue mass have been associated with outcomes in several malignancies, but studies in multiple myeloma (MM) are inconsistent. The aim of this study was to evaluate the association between muscle and fat areas and radiodensity, and overall survival (OS) in patients with newly diagnosed MM. We included 341 patients diagnosed with MM from 2010–2019 who had an 18F-fluorodeoxyglucose positron emission tomography/computed tomography at diagnosis. A cross-sectional image at the third lumbar vertebrae was segmented into muscle and fat components. Median follow up was 5.7 years. There was no association between sarcopenia and baseline disease characteristics or OS. Low muscle radiodensity was associated with higher disease stage, anemia, and renal failure. OS was 5.6 vs. 9.0 years in patients with muscle radiodensity in the lower vs. middle/upper tertiles, respectively (P = 0.02). High subcutaneous adipose tissue (SAT) radiodensity was associated with higher stage, anemia, thrombocytopenia, hypercalcemia, renal failure, and high LDH. OS was 5.4 years vs. not reached in patients with SAT radiodensity in the upper vs. middle/lower tertiles, respectively (P = 0.001). In conclusion, sarcopenia was not associated with OS in MM patients. High SAT radiodensity and low muscle radiodensity were associated with advanced disease stage and adverse laboratory characteristics.

Combined impact of myosteatosis and liver steatosis on prognosis in stage I-III colorectal cancer patients.

Myosteatosis and liver steatosis (LS) have been recognized as patient-derived image biomarkers that correlate with prognosis in colorectal cancer (CRC) patients. However, the significance of considering fat deposition in multiple body areas simultaneously has been underestimated. This study aimed to investigate the combined effect of myosteatosis and LS in stage I-III CRC patients. A total of 616 stage I-III CRC patients were included in the study. Myosteatosis was assessed using skeletal muscle radiodensity (SMD), and LS was estimated by calculating the Hounsfield unit of the liver and spleen ratio (LSR). Cox proportional hazard models were utilized to evaluate disease-free survival (DFS). A combination of myosteatosis and LS was proposed, and its discriminatory performance was compared using the C-index. Among the 616 participants, the median (interquartile) age was 64 (55-72) years, and 240 (38.9%) were female. The median and interquartile range of LSR were determined as 1.106 (0.967-1.225). The optimal cutoff value for LSR was identified as 1.181, leading to the classification of patients into low (410, 66.5%) and high LSR (206, 33.4%) groups. Among the patients, 200 were categorized into the low SMD group, while 416 were allocated to the high SMD group. Both myosteatosis and LS were identified as independent prognostic factors in the multivariable analysis. The combination of these two variables resulted in a three-group classification: high SMD with low LSR group, high SMD with high LSR group, and low SMD group. When comparing the C-index values, the three-group classification exhibited superior discriminatory performance compared with considering myosteatosis and LS separately. Myosteatosis was associated with poorer survival, while the presence of LS was linked to a better prognosis in non-metastatic CRC patients. Simultaneously considering fat infiltration can serve as a more effective prognosticator in non-metastatic CRC patients.

Establishment and application of the BRP prognosis model for idiopathic pulmonary fibrosis

BackgroundIdiopathic pulmonary fibrosis (IPF) is the most common idiopathic interstitial lung disease. Clinical models to accurately evaluate the prognosis of IPF are currently lacking. This study aimed to construct an easy-to-use and robust prediction model for transplant-free survival (TFS) of IPF based on clinical and radiological information.MethodsA multicenter prognostic study was conducted involving 166 IPF patients who were followed up for 3 years. The end point of follow-up was death or lung transplantation. Clinical information, lung function tests, and chest computed tomography (CT) scans were collected. Body composition quantification on CT was performed using 3D Slicer software. Risk factors in blood routine examination-radiology-pulmonary function (BRP) were identified by Cox regression and utilized to construct the “BRP Prognosis Model”. The performance of the BRP model and the gender-age-physiology variables (GAP) model was compared using time-ROC curves, calibration curves, and decision curve analysis (DCA). Furthermore, histopathology fibrosis scores in clinical specimens were compared between the different risk stratifications identified by the BRP model. The correlations among body composition, lung function, serum inflammatory factors, and profibrotic factors were analyzed.ResultsNeutrophil percentage > 68.3%, pericardial adipose tissue (PAT) > 94.91 cm3, pectoralis muscle radiodensity (PMD) ≤ 36.24 HU, diffusing capacity of the lung for carbon monoxide/alveolar ventilation (DLCO/VA) ≤ 56.03%, and maximum vital capacity (VCmax) < 90.5% were identified as independent risk factors for poor TFS among patients with IPF. We constructed a BRP model, which showed superior accuracy, discrimination, and clinical practicability to the GAP model. Median TFS differed significantly among patients at different risk levels identified by the BRP model (low risk: TFS > 3 years; intermediate risk: TFS = 2–3 years; high risk: TFS ≈ 1 year). Patients with a high-risk stratification according to the BRP model had a higher fibrosis score on histopathology. Additionally, serum proinflammatory markers were positively correlated with visceral fat volume and infiltration.ConclusionsIn this study, the BRP prognostic model of IPF was successfully constructed and validated. Compared with the commonly used GAP model, the BRP model had better performance and generalization with easily obtainable indicators. The BRP model is suitable for clinical promotion.

Different computed tomography parameters for defining myosteatosis in patients with advanced non-small cell lung cancer

Myosteatosis, excess muscle fat infiltration, is a novel prognostic factor in cancer patients. To define myosteatosis, skeletal muscle radiodensity (SMD) is most commonly used, while intramuscular adipose tissue (IMAT) is newly introduced. We aimed to compare SMD-defined and IMAT-defined myosteatosis for predicting overall survival (OS) in patients with advanced non-small cell lung cancer (NSCLC) and to explore whether patients with both low SMD and high IMAT had a shorter OS than patients with low SMD or high IMAT alone. We consecutively and prospectively recruited adult patients with stage IIIB or IV NSCLC at a teaching hospital. The mean SMD of all skeletal muscle areas and the area of IMAT on the unenhanced chest computed tomography (CT) images at the 12th thoracic vertebral level were segmented using Mimics version 21.0. Myosteatosis was defined by either low SMD (SMD-defined myosteatosis) or high IMAT (IMAT-defined myosteatosis). The optimal cutoffs for low SMD and high IMAT were also determined using the maximally selected rank statistics method. We calculated hazard ratios (HRs) and the corresponding confidence intervals (CIs) to evaluate the associations of OS with low SMD, high IMAT, and a combination of them. We included 565 patients (345 men and 220 women; mean age 58.5±9.0 years). Lower IMAT exhibited a tendency toward a favorable prognosis in men (p=0.0015) and women (p<0.0001); whereas higher SMD tended to have a favorable prognosis in men (p=0.0006) and women (p<0.0001). At baseline, 423 (74.9%) participants had high IMAT, 432 (76.5%) participants had low SMD and 370 (65.5%) participants had both high IMAT and low SMD. Compared to those without either high IMAT or low SMD, the participants with either high IMAT or low SMD had a shorter OS, while the participants with both High IMAT and Low SMD had the shortest OS (log-rank p<0.0001). After adjustment for the same confounders, high IMAT (HR, 1.44; 95% CI, 1.10-1.87) and low SMD (HR, 1.92; 95% CI, 1.36-2.43) were separately associated with poor prognosis. Moreover, the combination of high IMAT and low SMD indicated a higher risk of poor prognosis (HR, 2.43; 95% CI, 1.62-3.66). Both SMD-defined and IMAT-defined myosteatosis are highly prevalent in patients with advanced NSCLC and may serve as independent prognostic factors for OS. The diagnosis of myosteatosis might consider a combination of low SMD and high IMAT because this would help identify patients at a higher risk of mortality.

Direct deep learning-based survival prediction from pre-interventional CT prior to transcatheter aortic valve replacement

PurposeTo investigate survival prediction in patients undergoing transcatheter aortic valve replacement (TAVR) using deep learning (DL) methods applied directly to pre-interventional CT images and to compare performance with survival models based on scalar markers of body composition. MethodThis retrospective single-center study included 760 patients undergoing TAVR (mean age 81 ± 6 years; 389 female). As a baseline, a Cox proportional hazards model (CPHM) was trained to predict survival on sex, age, and the CT body composition markers fatty muscle fraction (FMF), skeletal muscle radiodensity (SMRD), and skeletal muscle area (SMA) derived from paraspinal muscle segmentation of a single slice at L3/L4 level. The convolutional neural network (CNN) encoder of the DL model for survival prediction was pre-trained in an autoencoder setting with and without a focus on paraspinal muscles. Finally, a combination of DL and CPHM was evaluated. Performance was assessed by C-index and area under the receiver operating curve (AUC) for 1-year and 2-year survival. All methods were trained with five-fold cross-validation and were evaluated on 152 hold-out test cases. ResultsThe CNN for direct image-based survival prediction, pre-trained in a focussed autoencoder scenario, outperformed the baseline CPHM (CPHM: C-index = 0.608, 1Y-AUC = 0.606, 2Y-AUC = 0.594 vs. DL: C-index = 0.645, 1Y-AUC = 0.687, 2Y-AUC = 0.692). Combining DL and CPHM led to further improvement (C-index = 0.668, 1Y-AUC = 0.713, 2Y-AUC = 0.696). ConclusionsDirect DL-based survival prediction shows potential to improve image feature extraction compared to segmentation-based scalar markers of body composition for risk assessment in TAVR patients.

Establishment and validation of novel nomograms to predict muscle quality in colorectal cancer patients

ObjectivesThe skeletal muscle mass index and skeletal muscle radiodensity have promise as specific diagnostic indicators for muscle quality. However, the difficulties in measuring low skeletal muscle mass index and low skeletal muscle radiodensity limit their use in routine clinical practice, impeding early screening and diagnosis. The objective of this study is to develop a nomogram that incorporates preoperative factors for predicting low skeletal muscle mass index and low skeletal muscle radiodensity. MethodsA total of 1692 colorectal cancer patients between 2015 and 2021 were included. The patients were randomly divided into a training cohort (n = 1353) and a validation cohort (n = 339). Nomogram models were calibrated using the area under the curve, calibration curves, and the Hosmer-Lemeshow test to assess their predictive ability. Finally, a decision curve was applied to assess the clinical usefulness. ResultsIn a prediction model for low skeletal muscle mass index, age, body mass index, and grip strength were incorporated as variables. For low skeletal muscle radiodensity, age, sex, body mass index, serum hemoglobin level, and grip strength were included as predictors. In the training cohort, the area under the curve value for low skeletal muscle mass index was 0.750 (95% CI, 0.726–0.773), whereas for low skeletal muscle radiodensity, it was 0.763 (95% CI, 0.739–0.785). The Hosmer-Lemeshow test confirmed that both models fit well in both cohorts. Decision curve analysis was applied to assess the clinical usefulness of the model. ConclusionsThe incorporation of preoperative factors into the nomogram-based prediction model represents a significant advancement in the muscle quality assessment. Its implementation has the potential to early screen patients at risk of low skeletal muscle mass index and low skeletal muscle radiodensity.

Low muscle radiodensity as a predictor of chemotherapy-induced peripheral neuropathy in epithelial ovarian cancer patients (1154)

Low muscle radiodensity as a predictor of chemotherapy-induced peripheral neuropathy in epithelial ovarian cancer patients (1154)

Deep learning–based assessment of CT markers of sarcopenia and myosteatosis for outcome assessment in patients with advanced pancreatic cancer after high-intensity focused ultrasound treatment

ObjectivesTo evaluate the prognostic value of CT-based markers of sarcopenia and myosteatosis in comparison to the Eastern Cooperative Oncology Group (ECOG) score for survival of patients with advanced pancreatic cancer treated with high-intensity focused ultrasound (HIFU).Materials and methodsFor 142 retrospective patients, the skeletal muscle index (SMI), skeletal muscle radiodensity (SMRD), fatty muscle fraction (FMF), and intermuscular fat fraction (IMFF) were determined on superior mesenteric artery level in pre-interventional CT. Each marker was tested for associations with sex, age, body mass index (BMI), and ECOG. The prognostic value of the markers was examined in Kaplan-Meier analyses with the log-rank test and in uni- and multivariable Cox proportional hazards (CPH) models.ResultsThe following significant associations were observed: Male patients had higher BMI and SMI. Patients with lower ECOG had lower BMI and SMI. Patients with BMI lower than 21.8 kg/m2 (median) also showed lower SMI and IMFF. Patients younger than 63.3 years (median) were found to have higher SMRD, lower FMF, and lower IMFF. In the Kaplan-Meier analysis, significantly lower survival times were observed in patients with higher ECOG or lower SMI. Increased patient risk was observed for higher ECOG, lower BMI, and lower SMI in univariable CPH analyses for 1-, 2-, and 3-year survival. Multivariable CPH analysis for 1-year survival revealed increased patient risk for higher ECOG, lower SMI, lower IMFF, and higher FMF. In multivariable analysis for 2- and 3-year survival, only ECOG and FMF remained significant.ConclusionCT-based markers of sarcopenia and myosteatosis show a prognostic value for assessment of survival in advanced pancreatic cancer patients undergoing HIFU therapy.Clinical relevance statementThe results indicate a greater role of myosteatosis for additional risk assessment beyond clinical scores, as only FMF was associated with long-term survival in multivariable CPH analyses along ECOG and also showed independence to ECOG in group analysis.Key Points• This study investigates the prognostic value of CT-based markers of sarcopenia and myosteatosis for patients with pancreatic cancer treated with high-intensity focused ultrasound.• Markers for sarcopenia and myosteatosis showed a prognostic value besides clinical assessment of the physical status by the Eastern Cooperative Oncology Group score. In contrast to muscle size measurements, the myosteatosis marker fatty muscle fraction demonstrated independence to the clinical score.• The results indicate that myosteatosis might play a greater role for additional patient risk assessments beyond clinical assessments of physical status.