Subcutaneous, but not visceral, adipose tissue as a marker for prognosis in gastric cancer patients with cachexia

Prognostic value of body composition in patients with digestive tract cancers: A prospective cohort study of 8,267 adults from China

BACKGROUND & AIMS

The characterization and prognostic value of body composition parameter/phenotype based on computed tomography (CT) in patients with digestive tract cancers remain incomplete. This study aimed to investigate the relationship between parameter/phenotype and clinical outcomes in patients with digestive tract cancers.

METHODS

In this prospective cohort study, 8267 patients with digestive tract cancers were assessed using CT scans to determine body composition. Body composition data, including areas of skeletal muscle (SM), subcutaneous adipose tissue (SAT), and visceral adipose tissue (VAT), were collected at the third lumbar level on CT images obtained within 30 days before surgery. Body composition phenotypes (sarcopenia, cancer cachexia, sarcopenic obesity) were determined based on SM, SAT, and VAT areas. The primary endpoint was overall survival, obtained from electronic medical records and telephone follow-up surveys. Kaplan-Meier and log-rank analyses were employed to compare unadjusted survival, while multivariate survival analyses were conducted using a proportional hazards model adjusted for age, gender, and cancer-node-metastasis (TNM) stages.

RESULTS

Adjusted hazard ratios (HRs) for all-cause mortality were calculated for the second (Q2), third (Q3), and fourth (Q4) quantiles relative to the first quantile (Q1) for SM areas, revealing adjusted summary HRs of 0.575 (95% CI, 0.361-0.916), 0.419 (95% CI, 0.241-0.729), and 0.384 (95% CI, 0.203-0.726), respectively. Sarcopenia-adjusted summary HRs were 1.795 (95% CI: 1.012-3.181) for male patients and 1.925 (95% CI: 1.065-3.478) for female patients. Cancer cachexia-adjusted summary HRs were 1.542 (95% CI: 1.023-2.324) for male patients and 1.569 (95% CI: 0.820-3.001) for female patients. Sarcopenic obesity-adjusted summary HRs were 1.122 (95% CI: 0.759-1.657) for male patients and 1.303 (95% CI: 0.623-2.725) for female patients. Subgroup analyses indicated varying prognostic values of body composition parameter/phenotype among different cancer types.

CONCLUSIONS

Our findings suggest a large SM area is a favorable prognostic indicator, while cancer cachexia and sarcopenia signify poor prognosis in patients with digestive tract cancers. These findings have important implications for the personalized preoperative assessment of body composition in patients with digestive tract cancers.

Utility of Combined Use of Imaging Features From Abdominopelvic CT and CA 125 to Identify Presence of CT Occult Peritoneal Metastases in Advanced Gastric Cancer

OBJECTIVE

The purpose of this study is to identify the presence of occult peritoneal metastasis (OPM) in patients with advanced gastric cancer (AGC) by using clinical characteristics and abdominopelvic computed tomography (CT) features.

METHODS

This retrospective study included 66 patients with OPM and 111 patients without peritoneal metastasis (non-PM [NPM]) who underwent preoperative contrast-enhanced CT between January 2020 and December 2021. Occult PMs means PMs that are missed by CT but later diagnosed by laparoscopy or laparotomy. Patients with NPM means patients have neither PM nor other distant metastases, indicating there is no evidence of distant metastases in patients with AGC. Patients' clinical characteristics and CT features such as tumor marker, Borrmann IV, enhancement patterns, and pelvic ascites were observed by 2 experienced radiologists. Computed tomography features and clinical characteristics were combined to construct an indicator for identifying the presence of OPM in patients with AGC based on a logistic regression model. Receiver operating characteristic curves and the area under the receiver operating characteristic curve (AUC) were generated to assess the diagnostic performance of the combined indicator.

RESULTS

Four independent predictors (Borrmann IV, pelvic ascites, carbohydrate antigen 125, and normalized arterial CT value) differed significantly between OPM and NPM and performed outstandingly in distinguishing patients with OPM from those without PM (AUC = 0.643-0.696). The combined indicator showed a higher AUC value than the independent risk factors (0.820 vs 0.643-0.696).

CONCLUSIONS

The combined indicator based on abdominopelvic CT features and carbohydrate antigen 125 may assist clinicians in identifying the presence of CT OPMs in patients with AGC.

Phosphatidylethanolamine (18:2e/18:2) may inhibit adipose tissue wasting in patients with cancer cachexia by increasing lysophosphatidic acid receptor 6

BACKGROUND

Cancer associated cachexia is characterized by the significant loss of adipose tissue, leading to devastating weight loss and muscle wasting in the majority of cancer patients. The effects and underlying mechanisms of degradation metabolites on adipocytes in cachectic patients remain poorly understood. To address this knowledge gap, we conducted a comprehensive study combining lipidomic analysis of subcutaneous and visceral adipose tissue with transcriptomics data from the database to investigate the mechanisms of lipid regulation in adipocytes.

METHODS

We collected subcutaneous and visceral adipose tissue samples from cachectic and noncachectic cancer patients. Lipidomic analysis was performed to identify differentially expressed lipids in both types of adipose tissue. Additionally, transcriptomics data from the GEO database were analyzed to explore gene expression patterns in adipocytes. Bioinformatics analysis was employed to determine the enrichment of differentially expressed genes in specific pathways. Furthermore, molecular docking studies were conducted to predict potential protein targets of specific lipids, with a focus on the PI3K-Akt signaling pathway. Western blot analysis was used to validate protein levels of the identified target gene, lysophosphatidic acid receptor 6 (LPAR6), in subcutaneous and visceral adipose tissue from cachectic and noncachectic patients.

RESULTS

Significant lipid differences in subcutaneous and visceral adipose tissue between cachectic and noncachectic patients were identified by multivariate statistical analysis. Cachectic patients exhibited elevated Ceramides levels and reduced CerG2GNAc1 levels (P < 0.05). A total of 10 shared lipids correlated with weight loss and IL-6 levels, enriched in Sphingolipid metabolism, GPI-anchor biosynthesis, and Glyceropholipid metabolism pathways. LPAR6 expression was significantly elevated in both adipose tissues of cachectic patients (P < 0.05). Molecular docking analysis indicated strong binding of Phosphatidylethanolamine (PE) (18:2e/18:2) to LPAR6.

CONCLUSIONS

Our findings suggest that specific lipids, including PE(18:2e/18:2), may mitigate adipose tissue wasting in cachexia by modulating the expression of LPAR6 through the PI3K-Akt signaling pathway. The identification of these potential targets and mechanisms provides a foundation for future investigations and therapeutic strategies to combat cachexia. By understanding the underlying lipid regulation in adipocytes, we aim to develop targeted interventions to ameliorate the devastating impact of cachexia on patient outcomes and quality of life. Nevertheless, further studies and validation are warranted to fully elucidate the intricate mechanisms involved and translate these findings into effective clinical interventions.

Elevated 18F-FDG uptake in subcutaneous adipose tissue correlates negatively with nutritional status and prognostic survival in cachexia patients with gastric cancer

BACKGROUND

Browning of white adipose tissue is a crucial factor contributing to adipose loss in cachexia patients, detectable via 18F-Fluorodeoxyglucose (18F-FDG) uptake. The present study elucidates the clinical relevance of 18F-FDG uptake in the subcutaneous adipose tissue of gastric cancer patients, specifically focusing on adipose browning and its implications on patient clinical parameters and prognosis.

METHODS

This investigation encompassed 770 gastric cancer patients, with PET-CT imaging and clinical data meticulously combined. The 18F-FDG uptake in subcutaneous adipose tissue at the third lumbar layer was quantified, and its correlation with clinical parameters, particularly those related to nutritional status and fat metabolism, was examined. Kaplan-Meier curves were subsequently employed to probe the relationship between 18F-FDG uptake and overall survival.

RESULTS

Of the 770 gastric cancer patients, 252 exhibited cancer-associated cachexia, while 518 did not. Cachectic patients demonstrated elevated 18F-FDG uptake in subcutaneous adipose tissue relative to non-cachectic patients (P < 0.001). Increased 18F-FDG uptake was also correlated with reduced plasma concentrations of albumin, prealbumin, hemoglobin, platelets, cholesterol, apolipoprotein A, low-density lipoprotein, and elevated IL-6 concentrations (all P < 0.05). A significant inverse correlation was observed between 18F-FDG uptake and BMI, albumin, low-density lipoprotein, cholesterol, and apolipoprotein A (all P < 0.05). Patients with higher 18F-FDG uptake exhibited diminished overall survival rates compared to those with lower 18F-FDG uptake (P = 0.0065). Furthermore, 18F-FDG uptake in subcutaneous adipose tissue was an independent prognostic indicator in gastric cancer patients (P = 0.028).

CONCLUSIONS

Browning of subcutaneous adipose tissue was markedly elevated in cachectic gastric cancer patients compared to non-cachectic counterparts. Increased 18F-FDG uptake in subcutaneous adipose tissue in cachectic gastric cancer patients was inversely correlated with nutritional status and survival prognosis.

Effect of visceral fat area on the accuracy of preoperative CT-N staging of colorectal cancer

OBJECTIVE

To investigate the effect of visceral fat area (VFA) on the accuracy of preoperative CT-N staging of colorectal cancer.

METHODS

We retrospectively reviewed the clinical and imaging data of 385 CRC patients who underwent surgical resection for colorectal cancer between January 2018 and July 2021. Preoperative CT-N staging and imaging features were determined independently by two radiologists. Using postoperative pathology as the gold standard, patients were divided into accurately and incorrectly staged groups, and clinical and imaging characteristics were compared between the two groups. VFA and subcutaneous fat area (SFA) at the L3 vertebral level, sex, age, BMI, tumor location, size, and tumor circumference ratio (TCR) were included. Logistic regression analysis was used to evaluate the independent factors influencing the accuracy of preoperative N staging of colorectal cancer.

RESULTS

Of the 385 patients enrolled, 259 (67.27%) were in the preoperative N-stage accurate staging group, and 126 (32.73%) were in the incorrectly staged group. Univariate analysis showed that there were significant differences in BMI, tumor location, VFA, SFA, size and TCR between the two groups (P<0.05). Logistic regression analysis showed that VFA (95% CI: 1.277, 3.813; P=0.005) and TCR (95% CI: 1.649, 17.545; P=0.005) were independent factors affecting the accuracy of N staging. The optimal cutoff points for VFA and TCR in predicting incorrect staging were 110 cm2 and 0.675, respectively.

CONCLUSIONS

Colorectal cancer patients with lower VFA and higher TCR and preoperative CT-N staging had an increased risk for diagnostic errors.

Coexistence of muscle atrophy and high subcutaneous adipose tissue radiodensity predicts poor prognosis in hepatocellular carcinoma

Introduction

We aimed to assess the prognostic implications of muscle atrophy and high subcutaneous adipose tissue (SAT) radiodensity in patients with hepatocellular carcinoma (HCC).

Methods

In this retrospective study, muscle atrophy was assessed using the psoas muscle index (PMI) obtained from computed tomography. SAT radiodensity was evaluated based on radiodensity measurements. Survival and multivariate analyses were performed to identify factors associated with prognosis. The impact of muscle atrophy and high SAT radiodensity on prognosis was determined through survival analysis.

Results

A total of 201 patients (median age: 71 years; 76.6% male) with HCC were included. Liver cirrhosis was observed in 72.6% of patients, and the predominant Child-Pugh grade was A (77.1%). A total of 33.3% of patients exhibited muscle atrophy based on PMI values, whereas 12.9% had high SAT radiodensity. Kaplan-Meier survival analysis demonstrated that patients with muscle atrophy had significantly poorer prognosis than those without muscle atrophy. Patients with high SAT radiodensity had a significantly worse prognosis than those without it. Muscle atrophy, high SAT radiodensity, the Barcelona Clinic Liver Cancer class B, C, or D, and Child-Pugh score ≥ 6 were significantly associated with overall survival. Further classification of patients into four groups based on the presence or absence of muscle atrophy and high SAT radiodensity revealed that patients with both muscle atrophy and high SAT radiodensity had the poorest prognosis.

Conclusion

Muscle atrophy and high SAT radiodensity are significantly associated with poor prognosis in patients with HCC. Identifying this high-risk subgroup may facilitate the implementation of targeted interventions, including nutritional therapy and exercise, to potentially improve clinical outcomes.

Development and application of the Cancer Cachexia Staging Index for the diagnosis and staging of cancer cachexia

OBJECTIVE

The current tools for evaluating cancer cachexia are either too simple to reflect the far-reaching effects of cachexia or too complicated to be used in daily practice. This study aimed to develop a cancer cachexia staging index (CCSI) that is both practical and comprehensive.

METHODS

Patients with gastrointestinal cancers were prospectively included in the study. Clinical data including weight change, body composition, systematic inflammation, nutrition, and function status were entered into regression models to determine the best variable combination as well as their respective cutoff values and score distribution in the CCSI. The CCSI's ability to predict outcomes and evaluate the consequences of cachexia for patients were then assessed.

RESULTS

Clinical information and test results from 10 568 patients were used to develop a CCSI composed of subjective and objective measures. Subjective measures included body mass index-adjusted weight loss grade, rate of weight loss, inflammation (neutrophil-to-lymphocyte ratio and C-reactive protein level), and prealbumin level. Objective measures included appetite status and physical status. Patients were diagnosed and stratified by the total CCSI score into 3 subgroups: no cachexia, mild or moderate cachexia, and severe cachexia. The CCSI grades showed good survival discrimination and were independently predictive of survival in multivariate analysis. Compared with the traditional Fearon criteria for diagnosing cancer cachexia, the CCSI was more accurate in predicting postoperative complications (net reclassification index [NRI], 2.8%; 95% CI, 0.0104-0.0456%), death (NRI, 10.68%; 95% CI, 0.0429-0.1708%), recurrence (NRI, 3.71%; 95% CI, 0.0082-0.0685%), and overall survival (NRI, 8.5%; 95% CI, 0.0219-0.1533%). The CCSI also had better discriminative ability than Fearon criteria in discriminating nutritional status, body composition, and systematic inflammation in patients with or without cachexia. A more detailed evaluation of a randomly selected subgroup (n = 1566) showed that CCSI grades had good discrimination of appetite and food intake status, physical function and muscle strength, symptom burden, and quality of life.

CONCLUSIONS

The CCSI is a comprehensive and practical evaluation tool for cancer cachexia. It can predict postoperative outcomes and survival. The CCSI stages showed good discrimination when evaluating patients with cancer in terms of nutritional status, physical function, systematic inflammation, body composition, symptom burden, and quality of life.

Evaluation and management of body composition changes in cancer patients

Wasting in cancer patients has long been recognized as a condition that adversely affects cancer patients' quality of life, treatment tolerance, and oncological outcomes. Historically, this condition was mainly evaluated by changes in body weight. However, this approach is not quite accurate because body weight is the overall change of all body compartments. Conditions such as edema and ascites can mask the severity of muscle and adipose tissue depletion. Changes in body composition assessment in cancer patients have historically been underappreciated because of the limited availability of measurement tools. As more evidence highlighting the importance of body composition has emerged, it is imperative to apply a more precise evaluation of nutritional status and a more targeted approach to provide nutritional support for cancer patients. In this review, we will discuss the modalities for evaluating body composition and how to manage body composition changes in cancer patients.

Associations of subcutaneous fat area and Systemic Immune-inflammation Index with survival in patients with advanced gastric cancer receiving dual PD-1 and HER2 blockade

BACKGROUND

Systemic Immune-inflammation Index (SII) and body composition parameters are easily assessed, and can predict overall survival (OS) in various cancers, allowing early intervention. This study aimed to assess the correlation between CT-derived body composition parameters and SII and OS in patients with advanced gastric cancer receiving dual programmed death-1 (PD-1) and human epidermal growth factor receptor 2 (HER2) blockade.

MATERIALS AND METHODS

This retrospective study enrolled patients with advanced gastric cancer treated with dual PD-1 and HER2 blockade from March 2019 to June 2022. We developed a deep learning model based on nnU-Net to automatically segment skeletal muscle, subcutaneous fat and visceral fat at the third lumbar level, and calculated the corresponding Skeletal Muscle Index, skeletal muscle density, subcutaneous fat area (SFA) and visceral fat area. SII was computed using the formula that total peripheral platelet count×neutrophil/lymphocyte ratio. Univariate and multivariate Cox regression analysis were used to determine the associations between SII, body composition parameters and OS.

RESULTS

The automatic segmentation deep learning model was developed to efficiently segment body composition in 158 patients (0.23 s/image). Multivariate Cox analysis revealed that high SII (HR=2.49 (95% CI 1.54 to 4.01), p<0.001) and high SFA (HR=0.42 (95% CI 0.24 to 0.73), p=0.002) were independently associated with OS, whereas sarcopenia was not an independent prognostic factor for OS (HR=1.41 (95% CI 0.86 to 2.31), p=0.173). In further analysis, patients with high SII and low SFA had worse long-term prognosis compared with those with low SII and high SFA (HR=8.19 (95% CI 3.91 to 17.16), p<0.001).

CONCLUSION

Pretreatment SFA and SII were significantly associated with OS in patients with advanced gastric cancer. A comprehensive analysis of SII and SFA may improve the prognostic stratification of patients with gastric cancer receiving dual PD-1 and HER2 blockade.

Cancer cachexia: molecular mechanisms and treatment strategies

Muscle wasting is a consequence of physiological changes or a pathology characterized by increased catabolic activity that leads to progressive loss of skeletal muscle mass and strength. Numerous diseases, including cancer, organ failure, infection, and aging-associated diseases, are associated with muscle wasting. Cancer cachexia is a multifactorial syndrome characterized by loss of skeletal muscle mass, with or without the loss of fat mass, resulting in functional impairment and reduced quality of life. It is caused by the upregulation of systemic inflammation and catabolic stimuli, leading to inhibition of protein synthesis and enhancement of muscle catabolism. Here, we summarize the complex molecular networks that regulate muscle mass and function. Moreover, we describe complex multi-organ roles in cancer cachexia. Although cachexia is one of the main causes of cancer-related deaths, there are still no approved drugs for cancer cachexia. Thus, we compiled recent ongoing pre-clinical and clinical trials and further discussed potential therapeutic approaches for cancer cachexia.

Abdominal fat and muscle distributions in different stages of colorectal cancer

BACKGROUND

The purpose of this study is to explore the difference of abdominal fat and muscle composition, especially subcutaneous and visceral adipose tissue, in different stages of colorectal cancer (CRC).

MATERIALS AND METHODS

Patients were divided into 4 groups: healthy controls (patients without colorectal polyp), polyp group (patients with colorectal polyp), cancer group (CRC patients without cachexia), and cachexia group (CRC patients with cachexia). Skeletal muscle (SM), subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), and intermuscular adipose tissue (IMAT) were assessed at the third lumbar level on computed tomography images obtained within 30 days before colonoscopy or surgery. One-way ANOVA and linear regression were used to analyze the difference of abdominal fat and muscle composition in different stages of CRC.

RESULTS

A total of 1513 patients were divided into healthy controls, polyp group, cancer group, and cachexia group, respectively. In the development of CRC from normal mucosa to polyp and cancer, the VAT area of the polyp group was significantly higher than that of the healthy controls both in male (156.32 ± 69.71 cm² vs. 141.97 ± 79.40 cm², P = 0.014) and female patients (108.69 ± 53.95 cm² vs. 96.28 ± 46.70 cm², P = 0.044). However, no significant differences were observed of SAT area between polyp group and healthy controls in both sexes. SAT area decreased significantly in the male cancer group compared with the polyp group (111.16 ± 46.98 cm² vs. 126.40 ± 43.52 cm², P = 0.001), while no such change was observed in female patients. When compared with healthy controls, the SM, IMAT, SAT, and VAT areas of cachexia group was significantly decreased by 9.25 cm² (95% CI: 5.39-13.11 cm², P < 0.001), 1.93 cm² (95% CI: 0.54-3.32 cm², P = 0.001), 28.84 cm² (95% CI: 17.84-39.83 cm², P < 0.001), and 31.31 cm² (95% CI: 18.12-44.51 cm², P < 0.001) after adjusting for age and gender.

CONCLUSION

Abdominal fat and muscle composition, especially SAT and VAT, was differently distributed in different stages of CRC. It is necessary to pay attention to the different roles of subcutaneous and visceral adipose tissue in the development of CRC.

tsRNA Landscape and Potential Function Network in Subcutaneous and Visceral Pig Adipose Tissue

Noncoding RNAs (ncRNAs) called tsRNAs (tRNA-derived short RNAs) have the ability to regulate gene expression. The information on tsRNAs in fat tissue is, however, limited. By sequencing, identifying, and analyzing tsRNAs using pigs as animal models, this research reports for the first time the characteristics of tsRNAs in subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT). A total of 474 tsRNAs, 20 and 21 of which were particularly expressed in VAT and SAT, respectively, were found in WAT. According to the analysis of the tsRNA/miRNA/mRNA co-expression network, the tsRNAs with differential expression were primarily engaged in the endocrine and immune systems, which fall under the classification of organic systems, as well as the global and overview maps and lipid metropolis, which fall under the category of metabolism. This research also discovered a connection between the activity of the host tRNA engaged in translation and the production of tsRNAs. This research also discovered that tRF-Gly-GCC-037/tRF-Gly-GCC-042/tRF-Gly-CCC-016 and miR-218a/miR281b may be involved in the regulation of fatty acid metabolism in adipose tissue through SCD based on the tsRNA/miRNA/mRNA/fatty acid network. In conclusion, our findings enrich the understanding of ncRNAs in WAT metabolism and health regulation, as well as reveal the differences between SAT and VAT at the level of tsRNAs.

Body Composition of Patients Undergoing Radical Cystectomy for Bladder Cancer: Sarcopenia, Low Psoas Muscle Index, and Myosteatosis Are Independent Risk Factors for Mortality

Background: We assessed a wide array of body composition parameters to identify those most relevant as prognostic tools for patients undergoing radical cystectomy (RC) due to bladder cancer (BC). Methods: In this retrospective, single-center study, preoperative computed tomography (CT) scans of 657 patients were measured at the level of the 3rd lumbar vertebra (L3) to determine common body composition indices including sarcopenia, myosteatosis, psoas muscle index (PMI), subcutaneous and visceral fat index (SFI and VFI), visceral-to-subcutaneous fat ratio (VSR), and visceral obesity. Predictors of overall survival (OS) and cancer-specific survival (CSS) were identified in univariate and multivariate survival analysis. Results: Sarcopenia and a low PMI were independently associated with shorter OS (Sarcopenia: HR 1.30; 95% CI 1.02–1.66; p = 0.04 and a low PMI: HR 1.32; 95% CI 1.02–1.70; p = 0.03) and CSS (Sarcopenia: HR 1.64; 95% CI 1.19–2.25; p < 0.01 and a low PMI: HR 1.41; 95% CI 1.02–1.96; p = 0.04). Myosteatosis, measured as decreasing average Hounsfield units of skeletal muscle, was an independent risk factor for OS (HR 0.98; 95% CI 0.97–1.00; p = 0.01) and CSS (HR 0.98; 95% CI 0.96–1.00; p < 0.05). The assessed adipose tissue indices were not significant predictors for OS and CSS. Conclusions: Sarcopenia, a low PMI, and myosteatosis are independent predictors for OS and CSS in patients undergoing radical cystectomy for bladder cancer.

Development and validation of a cancer cachexia risk score for digestive tract cancer patients before abdominal surgery

BACKGROUND

Cancer cachexia is prevalent in digestive tract cancer patients and has significant impacts on prognosis; it is vital to identify individuals who are at risk of cancer cachexia to allow for appropriate evaluation and treatment. This study evaluated whether digestive tract cancer patients with a risk of cancer cachexia and who had a risk of adverse survival could be identified before abdominal surgery.

METHODS

This large-scale cohort study involved patients who underwent abdominal surgery between January 2015 and December 2020 to treat digestive tract cancer. Participants were allocated to the development cohort, the validation cohort, or the application cohort. Univariate and multivariate analyses of the development cohort were performed to detect distinct risk variables for cancer cachexia to create a cancer cachexia risk score. The performance of the risk score across all the three cohorts was assessed through calculating the area under the receiver operating characteristic curve (AUC), as well as calibration and decision curves. We tested how well the score predicted survival outcomes in the application cohort.

RESULTS

A total of 16 264 patients (median 64 years of age; 65.9% male) were included, with 8743 in the development cohort, 5828 in the validation cohort, and 1693 in the application cohort. Seven variables were identified as independent predictive factors and were included in the cancer cachexia risk score: cancer site, cancer stage, time from symptom onset to hospitalization, appetite loss, body mass index, skeletal muscle index, and neutrophil-lymphocyte ratio. The risk score predicting cancer cachexia owns a good discrimination, with the mean AUC of 0.760 (P < 0.001) in the development cohort, 0.743 (P < 0.001) in the validation cohort, and 0.751 (P < 0.001) in the application cohort, respectively, and had an excellent calibration (all P > 0.05). The decision curve analysis revealed net benefits of the risk score across a range of risk thresholds in the three cohorts. In the application cohort, compared with the high-risk group, the low-risk group experienced significantly longer overall survival [hazard ratio (HR) 2.887, P < 0.001] as well as relapse-free survival (HR 1.482, P = 0.01).

CONCLUSIONS

The cancer cachexia risk score constructed and validated demonstrated good performance in identifying those digestive tract cancer patients before abdominal surgery at a higher risk of cancer cachexia and unfavourable survival. This risk score can help clinicians to enhance their capabilities to screen for cancer cachexia, assess patient prognosis, and strengthen early decision-making on targeted approaches to attune cancer cachexia for digestive tract cancer patients before abdominal surgery.

Fat Loss in Patients with Metastatic Clear Cell Renal Cell Carcinoma Treated with Immune Checkpoint Inhibitors

The purpose of this study was to determine the prognostic impact of fat loss after immune checkpoint inhibitor (ICI) treatment in patients with metastatic clear cell renal cell carcinoma (ccRCC). Data from 60 patients treated with ICI therapy for metastatic ccRCC were retrospectively analyzed. Changes in cross-sectional areas of subcutaneous fat (SF) between the pre-treatment and post-treatment abdominal computed tomography (CT) images were expressed as percentages and were divided by the interval between the CT scans to calculate ΔSF (%/month). SF loss was defined as ΔSF < -5%/month. Survival analyses for overall survival (OS) and progression-free survival (PFS) were performed. Patients with SF loss had shorter OS (median, 9.5 months vs. not reached; p < 0.001) and PFS (median, 2.6 months vs. 33.5 months; p < 0.001) than patients without SF loss. ΔSF was independently associated with OS (adjusted hazard ratio (HR), 1.49; 95% confidence interval (CI), 1.07-2.07; p = 0.020) and PFS (adjusted HR, 1.57; 95% CI, 1.17-2.12; p = 0.003), with a 5%/month decrease in SF increasing the risk of death and progression by 49% and 57%, respectively. In conclusion, Loss of SF after treatment initiation is a significant and independent poor prognostic factor for OS and PFS in patients with metastatic ccRCC who receive ICI therapy.

Triceps skinfold-albumin index significantly predicts the prognosis of cancer cachexia: A multicentre cohort study

BACKGROUND

The fat mass and nutritional status play important roles in the onset and progression of cancer cachexia. The present study evaluated the joint prognostic value of the fat mass, as indicated by the triceps skinfold thickness (TSF), and the serum albumin level, for mortality in patients with cancer cachexia.

METHODS

We performed a multicentre cohort study including 5134 patients with cancer cachexia from January 2013 to April 2019. The sum of the TSF (mm) and serum albumin (g/L) was defined as the triceps skinfold-albumin index (TA). Harrell's C index, a time-dependent receiver operating characteristic (ROC) curve analysis and the area under the curve (AUC) were used to evaluate the prognostic performance of the TA and other indices. Optimal stratification was used to identify the thresholds to define a low TA, and the association of the TA with all-cause mortality was evaluated using Kaplan-Meier analysis and Cox proportional hazard regression models.

RESULTS

The study enrolled 2408 women and 2726 men with a median age of 58.6 years and a median follow-up of 44 months. A total of 607 women (TA < 49.9) and 817 men (TA < 45.6) were classified as having a low TA. The TA showed better discrimination performance (C index = 0.621, 95% confidence interval [CI] = 0.607-0.636) to predict mortality in patients with cancer cachexia than the handgrip strength, the nutritional risk index, the prognostic nutritional index, the controlling nutritional status index, the systemic immune-inflammation index, the modified Glasgow prognostic score, and the TSF or albumin alone in the study population (all P < 0.05). The 1-, 3- and 5-year time-dependent ROC analyses (AUC = 0.647, 0.625 and 0.630, respectively) showed that the TA had the highest prognostic value among all indices investigated (all P < 0.05). Univariate analysis showed that a lower TA was associated with an increased death hazard (hazard ratio [HR] = 1.859, 95% CI = 1.677-2.062), regardless of the sex and cancer type. Multivariable survival analysis showed that a lower TA was independently associated with an increased death hazard (HR = 1.381, 95% CI = 1.223-1.560). This association was significantly strengthened in patients who did not receive curative chemotherapy (HR = 1.491, 95% CI = 1.298-1.713), those who had higher serum total protein levels (HR = 1.469, 95% CI = 1.284-1.681) and those with better physical performance (HR = 1.453, 95% CI = 1.271-1.662).

CONCLUSIONS

This study defined and evaluated a new prognostic index, the TA, which may improve the selection of intervention strategies to optimize the survival of patients with cancer cachexia.

Body Composition as a Comorbidity-Independent Predictor of Survival following Nephroureterectomy for Urothelial Cancer of the Upper Urinary Tract

Radical nephroureterectomy (NUE) is the gold standard treatment for high-risk urothelial cancer of the upper urinary tract (UTUC). Besides sarcopenia and frailty, fat distribution is moving increasingly into focus. Components of body composition were assessed in patients undergoing NUE due to UTUC. The study cohort included 142 patients. By using CT-based measurements, the skeletal muscle index (SMI), subcutaneous adipose tissue index (SATI), and visceral adipose tissue index (VATI) were measured at the height of the third lumbar vertebra. Overall survival (OS) and cancer-specific survival (CSS) were estimated using univariable und multivariable Cox regression models. The prevalence of sarcopenia in the study population (n = 142) was 37%. OS and CSS were significantly reduced in sarcopenic patients. In the multivariable cox regression analysis, including age, ACE-27, T-stage, R-stage, LVI and necrosis, sarcopenia remained a significant risk factor of OS (HR, 1.77; 95% CI 1.02-3.07; p = 0.042) and CSS (HR, 2.17; 95% CI 1.18-3.99; p = 0.012). High visceral adipose tissue seems to be protective, although not statistically significant. Sarcopenia is a comorbidity-independent risk factor in patients who underwent NUE due to UTUC. Visceral fat represents a potentially protective factor. These results suggest that specific factors of body composition can be used for better risk stratification.

Analysis of different adipose depot gene expression in cachectic patients with gastric cancer

Purpose

This study aimed to identify the differentially expressed genes (DEGs) that contributed to the different amount of fat loss between subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) among cachectic patients.

Methods

RNA sequencing was performed and bioinformatic tools were utilized to analyze the biological functions and construct regulation networks of DEGs. We presumed that iroquois homeobox 1 (IRX1) to be a hub gene and analyzed its clinical significance. Mouse model of cancer cachexia was established and differences between SAT and VAT were compared. The function of IRX1 on lipid metabolism was clarified by Oil Red O staining, qRT-PCR, and Western blotting in adipocytes.

Results

A total of 455 DEGs were screened between SAT and VAT in cachectic patients. Several hub genes were selected and IRX1 was presumed to contribute to the pathological difference between SAT and VAT in cancer cachexia. Patients with higher expression of IRX1 in SAT than VAT revealed significantly higher weight loss, IL-6 and TNF-α, as well as lower BMI, SAT, and VAT area. IRX1 expression in SAT was negatively correlated with SAT area. In cachectic mice, the expression of IRX1 in SAT was significantly higher than that in VAT. The inhibition effect on adipogenesis exerted by IRX1 was also proved in vitro.

Conclusion

These data supported that DEGs contribute to the different degrees of fat loss among adipose depots in cachectic patients. IRX1 in SAT promoted fat loss by inhibiting adipocyte differentiation and adipogenesis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-022-00708-x.

The evolving view of thermogenic fat and its implications in cancer and metabolic diseases

The incidence of metabolism-related diseases like obesity and type 2 diabetes mellitus has reached pandemic levels worldwide and increased gradually. Most of them are listed on the table of high-risk factors for malignancy, and metabolic disorders systematically or locally contribute to cancer progression and poor prognosis of patients. Importantly, adipose tissue is fundamental to the occurrence and development of these metabolic disorders. White adipose tissue stores excessive energy, while thermogenic fat including brown and beige adipose tissue dissipates energy to generate heat. In addition to thermogenesis, beige and brown adipocytes also function as dynamic secretory cells and a metabolic sink of nutrients, like glucose, fatty acids, and amino acids. Accordingly, strategies that activate and expand thermogenic adipose tissue offer therapeutic promise to combat overweight, diabetes, and other metabolic disorders through increasing energy expenditure and enhancing glucose tolerance. With a better understanding of its origins and biological functions and the advances in imaging techniques detecting thermogenesis, the roles of thermogenic adipose tissue in tumors have been revealed gradually. On the one hand, enhanced browning of subcutaneous fatty tissue results in weight loss and cancer-associated cachexia. On the other hand, locally activated thermogenic adipocytes in the tumor microenvironment accelerate cancer progression by offering fuel sources and is likely to develop resistance to chemotherapy. Here, we enumerate current knowledge about the significant advances made in the origin and physiological functions of thermogenic fat. In addition, we discuss the multiple roles of thermogenic adipocytes in different tumors. Ultimately, we summarize imaging technologies for identifying thermogenic adipose tissue and pharmacologic agents via modulating thermogenesis in preclinical experiments and clinical trials.

Identifying Key Genes and Functionally Enriched Pathways of Diverse Adipose Tissue Types in Cattle

Background: Fat is a tissue that not just stores energy and plays a protective role; it is also a vital endocrine organ that generates and integrates signals to influence metabolism. Meanwhile, the excessive accumulation of lipids in adipose tissue can lead to metabolic disturbance and diseases. To date, the complicated molecular mechanisms of bovine adipose tissue are still unknown. This study aimed to identify key genes and functionally enriched pathways in various adipose tissue types.

Results: The RNAseq data of 264 samples were downloaded from Gene Expression Omnibus (GEO) and analyzed by weighted gene co-expression network analysis (WGCNA). We identified 19 modules that significantly associated with at least one adipose tissue type. The brown module from GSE39618 was most closely associated with intramuscular fat tissue, which contained 550 genes. These genes were significantly enriched in pathways that related to inflammation and disease, such as TNF signaling pathway, IL-17 signaling pathway, and NF-kappa B signaling pathway. The pink module (GSE39618) that contained 58 genes was most closely associated with omental fat tissue. The turquoise (GSE39618), blue (GSE116775), and yellow (GSE65125) module were most closely associated with subcutaneous fat tissue. Genes in these modules were significantly enriched in pathways related to fat metabolism, such as the PPAR signaling pathway, fatty acid metabolism and PI3K-Akt signaling pathway. At last, key genes for intramuscular fat (PTGS2 and IL6), omental fat (ARHGEF5 and WT1), and subcutaneous fat (KIT, QR6Q1, PKD2L1, etc.) were obtained and verified. In addition, it was found that IL10 and VCAM1 might be potential genes to distinguish adipose and muscle.

Conclusion: The study applied WGCNA to generate a landscape of adipose tissue and provide a basis for identifying potential pathways and hub genes of different adipose tissue types.

Histomorphological and inflammatory changes of white adipose tissue in gastrointestinal cancer patients with and without cachexia

BACKGROUND

During cancer cachexia, several alterations occur in peripheral tissues, and the adipose tissue may be involved during the catabolic state. We aimed at investigating histological rearrangement and infiltration of inflammatory cells in subcutaneous adipose tissue (SAT) of patients with cancer undergoing surgery, according to the presence/absence of cachexia.

METHODS

We considered gastrointestinal cancer patients and controls with non-malignant diseases undergoing surgery. We collected SAT samples and performed histomorphological analyses [cross-sectional area (CSA) and per cent of fibrosis] and immunohistochemistry to characterize the inflammatory cells. By computed tomography (CT) scan, we calculated SAT and visceral adipose tissue (VAT).

RESULTS

We enrolled 51 participants (31 gastrointestinal cancer patients and 20 controls). In cancer patients, cachexia was present in 13/31 (42%). The CSA (μm² ) of the adipocytes from SAT was reduced in cancer patients vs. controls (3148, inter-quartile range 2574-3755 vs. 4474, inter-quartile range 3654-5183) (P < 0.001), in particular in cachectic patients vs. non-cachectic (median 2518 vs. median 3470) (P = 0.03) and in cachectic vs. controls (P < 0.001), as well as in non-cachectic vs. controls (P = 0.04). The median per cent of fibrosis was higher in cancer patients vs. controls (9 vs. 3) (P = 0.0001), in particular in cachectic vs. non-cachectic (13.35 vs. 7.13) (P = 0.03). We observed a higher number of macrophages (CD68) (P = 0.0001) and T lymphocytes (CD3) (P = 0.002) in SAT of cancer patients vs. controls, and the number of T lymphocytes was higher in cachectic vs. non-cachectic patients (P = 0.025). Anorexic cancer patients showed in SAT a higher number of macrophages and T lymphocytes with respect to controls (P < 0.0001), whereas no difference was present between anorexic and non-anorexic patients. At CT scan, cachectic patients showed lower VAT and SAT vs. non-cachectic (VAT: 97.64 ± 40.79 vs. 212.53 ± 79.24, P = 0.0002; SAT: 126.27 ± 87.92 vs. 206.27 ± 61.93, P = 0.01, respectively). Cancer patients with low CSA, high degree of fibrosis, and high number of T lymphocytes presented with lower body mass index and lower SAT and VAT at CT scan (P ≤ 0.01).

CONCLUSIONS

We found histological alterations of SAT among gastrointestinal cancer patients and in particular significant changes in CSA, fibrosis, and inflammation when cachexia was present; the changes in histomorphological parameters of the adipocytes reflected alterations in adiposity at body composition analysis.