Visceral and subcutaneous fat as new independent predictive factors of survival in locally advanced gastric carcinoma patients treated with neo-adjuvant chemotherapy

New Perspectives for Estimating Body Composition From Computed Tomography: Clothing Associated Artifacts

As the value of clinical imaging is expanded through retrospective analyses, it is imperative that all efforts are made to optimize validity. Such considerations for retrospective designs should prioritize factors like naturalistic conditions for observations and measurement replicability, while avoiding sample biases and reliance on strict clinical timelines. Valid methodological approaches are immanent for successful translation from retrospective observational designs into prospective pragmatic research with actionable potential. In particular, thousands of studies have sought to associate clinical outcomes to measures of body composition across diverse patient groups. Post-hoc use of computed tomography (CT) to quantify adiposity and lean tissue characteristics has most frequently involved just a single slice at the level of the third lumbar vertebrae (L3). Abundant in statistical significance and inconsistencies alike, such methods have yet to be implemented or deemed valuable for making real-world clinical decisions. We present herein a concerning perspective, for both magnitude and prevalence, of a widely overlooked source of data variability for this methodology: the hinderance of pants and other tightly fit clothing.

Preoperative visceral fat index predicts the survival outcomes of patients with gastric cancer after surgery

Visceral adipose tissue and skeletal muscle mass are associated with carcinogenesis and clinical outcomes in patients with cancer. The aim of the present study was to determine the influence of body composition parameters on postoperative survival in patients with gastric cancer. Demographic data and systemic inflammatory response data were obtained from patients with gastric cancer undergoing radical gastrectomy. The patient's skeletal muscle and visceral fat were assessed using computed tomography, and the corresponding skeletal muscle index (SMI) and visceral fat index (VFI) were calculated. Univariate and multivariate analyses were then performed. Of the 342 patients from whom information was collected, 125 of these patients eventually succumbed to the disease. A total of 271 (79.24%) of the patients were male and 71 (20.76%) were female. Regarding the entire cohort, the mean age was 64 years [interquartile range (IQR), 56-74 years], while the mean body mass index collected was 21.53 (IQR, 19.27-24.22). The median SMI and VFI of the patients were 47.73 (IQR, 41.67-55.51) and 41.28 (IQR, 36.62-45.36), respectively. It was concluded that a low SMI and VFI were associated with worse survival outcomes. However, the neutrophil-to-lymphocyte ratio and perioperative blood transfusion were not significantly associated with overall survival (OS). Among the indicators assessed, a low VFI was an independent risk factor associated with the worst OS time (hazard ratio 1.59; confidence interval, 1.03-2.45; P=0.038). Finally, a prognostic nomogram was constructed which included the VFI to assist clinicians in making more informed decisions. In conclusion, after data collection and analysis, it was found that there was a significant correlation between a low VFI and a shorter OS time in patients with gastric cancer following gastrectomy, suggesting that VFI may be a promising therapeutic target for postoperative interventions to improve patient survival further.

Abdominal adipose tissue distribution assessed by computed tomography and mortality in hospitalised patients with COVID-19: a retrospective longitudinal cohort study

BACKGROUND

Visceral adiposity has been associated with an increased risk of critical illness in COVID-19 patients. However, if it also associates to a poor survival is still not well established. The aim of the study was to assess the relationship between abdominal fat distribution and COVID-19 mortality.

METHODS

In this six-month longitudinal cohort study, abdominal visceral (VAT) and subcutaneous adipose tissues (SAT) were measured by computed tomography in a cohort of 174 patients admitted to the emergency department with a diagnosis of COVID-19, during the first wave of pandemic. The primary exposure and outcome measures were VAT and SAT at hospital admission, and death at 30 and 180 days, respectively.

RESULTS

Overall survival was not different according to VAT (p = 0.94), SAT (p = 0.32) and VAT/SAT ratio (p = 0.64). However, patients in the lowest SAT quartile (thickness ≤ 11.25 mm) had a significantly reduced survival compared to those with thicker SAT (77 vs. 94% at day 30; 74 vs. 91% at day 180, p = 0.01). Similarly, a thinner SAT was associated with lower survival in Intensive Care Unit (ICU) admitted patients, independently of sex or age (p = 0.02). The VAT/SAT ratio showed a non-linear increased risk of ICU admission, which plateaued out and tended for inversion at values greater than 1.9 (p = 0.001), although was not associated with increased mortality rate.

CONCLUSIONS

In our cohort, visceral adiposity did not increase mortality in patients with COVID-19, but low SAT may be associated with poor survival.

Impact of Preoperative Nutritional Assessment on Other-Cause Survival after Gastrectomy in Patients with Gastric Cancer

This study aimed to clarify the factors associated with death due to other diseases after a gastrectomy for gastric cancer. This retrospective cohort study included consecutive patients who had undergone gastrectomy between April 2008 and June 2018 for primary stage II-III gastric cancer. The primary outcome was other-cause survival. To identify prognostic factors for other-cause survival for univariate analysis, we used a Cox proportional hazard regression model. A total of 512 patients met the inclusion criteria. The average age was 67.93 years, and the average body mass index was 22.75 kg/m², with 84 (16.4%) being moderately malnourished and 88 (17.2%) being severely malnourished, as defined by the Global Leadership Initiative on Malnutrition (GLIM) criteria. The other-cause survival for the malnourished group was significantly worse than that for the normal group (p < 0.001). The prognosis was worse when the severity of malnutrition was worse (p < 0.001). Multivariate analysis showed that severe malnutrition was significantly independent of prognostic factors for other-cause survival (hazard ratio: 3.310; 95% confidence interval: 1.426-7.682; p = 0.005). Undernutrition, as defined by the GLIM criteria, is useful for the preoperative prediction of death due to other diseases after gastrectomy in patients with advanced gastric cancer.

Association of visceral adipose tissue with postoperative outcome in upper gastrointestinal cancer: a systematic review and meta-analysis

BACKGROUND

There is no consensus on the relation between visceral fat mass and long-term postoperative prognosis in patients with upper gastrointestinal (GI) cancer.

OBJECTIVES

The purpose of this study was to investigate the association of preoperative visceral fat mass with postoperative complications and overall survival (OS) in patients with upper GI cancer.

METHODS

We searched MEDLINE, the Cochrane Central Register of Controlled Trials, EMBASE (Dialog), the WHO International Clinical Trials Platform Search Portal, and ClinicalTrials.gov and identified observational studies published from inception through 20 July 2022. We conducted a systematic review and random-effects meta-analysis of studies including patients who were surgically treated for upper GI cancer and whose visceral fat mass was assessed on the basis of body composition. We independently assessed the risk of bias and quality of evidence using the Quality In Prognosis Studies and the Grading of Recommendations, Assessment, Development, and Evaluation approach, respectively. The primary outcome was OS. HRs and 95% CIs for OS were pooled.

RESULTS

Ninety-one studies (n = 20,583) were included. All studies used computed tomography (CT) to assess the body composition of patients. Twenty-four studies reported the relation between high visceral fat and postoperative outcomes, and their results were synthesized. Compared with low visceral adipose tissue, high visceral adipose tissue assessed by CT may improve OS (HR: 0.69; 95% CI: 0.55, 0.87; I2 = 65%; n = 3407). The risk of bias for OS in each study was moderate or high. The certainty of evidence for OS was very low because of inconsistency in the forest plot, the moderate or high risk of bias, and publication bias.

CONCLUSIONS

High visceral fat may be associated with improved OS after radical resection in patients with upper GI cancer. Further studies are needed to confirm these findings and mitigate the risk.

Adiposity and cancer survival: a systematic review and meta-analysis

PURPOSE

The increasing availability of clinical imaging tests (especially CT and MRI) that directly quantify adipose tissue has led to a rapid increase in studies examining the relationship of visceral, subcutaneous, and overall adiposity to cancer survival. To summarize this emerging body of literature, we conducted a systematic review and meta-analysis of imaging-measured as well as anthropometric proxies for adipose tissue distribution and cancer survival across a wide range of cancer types.

METHODS

Using keywords related to adiposity, cancer, and survival, we conducted a systematic search of the literature in PubMed and MEDLINE, Embase, and Web of Science Core Collection databases from database inception to 30 June 2021. We used a random-effect method to calculate pooled hazard ratios (HR) and corresponding 95% confidence intervals (CI) within each cancer type and tested for heterogeneity using Cochran's Q test and the I2 test.

RESULTS

We included 203 records for this review, of which 128 records were utilized for quantitative analysis among 10 cancer types: breast, colorectal, gastroesophageal, head and neck, hepatocellular carcinoma, lung, ovarian, pancreatic, prostate, and renal cancer. We found that imaging-measured visceral, subcutaneous, and total adiposity were not significantly associated with increased risk of overall mortality, death from primary cancer, or cancer progression among patients diagnosed with these 10 cancer types; however, we found significant or high heterogeneity for many cancer types. For example, heterogeneity was similarly high when the pooled HRs (95% CI) for overall mortality associated with visceral adiposity were essentially null as in 1.03 (0.55, 1.92; I2 = 58%) for breast, 0.99 (0.81, 1.21; I2 = 71%) for colorectal, versus when they demonstrated a potential increased risk 1.17 (0.85, 1.60; I2 = 78%) for hepatocellular carcinoma and 1.62 (0.90, 2.95; I2 = 84%) for renal cancer.

CONCLUSION

Greater adiposity at diagnosis (directly measured by imaging) is not associated with worse survival among cancer survivors. However, heterogeneity and other potential limitations were noted across studies, suggesting differences in study design and adiposity measurement approaches, making interpretation of meta-analyses challenging. Future work to standardize imaging measurements and data analyses will strengthen research on the role of adiposity in cancer survival.

Preoperative Muscle-Adipose Index: A New Prognostic Factor for Gastric Cancer

BACKGROUND

Studies have shown that traditional nutrition indicators and body composition indicators are closely related to prognosis after radical gastric cancer (GC) surgery. However, the effect of the combined muscle and adipose composite on the prognosis of GC has not been reported.

METHODS

The clinicopathological data of 514 patients with GC were retrospectively analyzed. The skeletal muscle adipose tissue were measured by preoperative CT images to obtain the muscle index and adipose index. X-tile software was used to determine the diagnostic threshold of muscle-adipose imbalance.

RESULTS

The 5-year OS and RFS of the muscle-adipose imbalanced group were significantly worse than those of the balanced group. Multivariate analysis showed that muscle-adipose imbalance and the CONUT score were independent prognostic factors of OS and RFS (p < 0.05). The nuclear density curve showed that the recurrence risk of the muscle-adipose imbalanced group was higher than that of the balanced group, whereas the nuclear density curve of the CONUT score was confounded. Incorporating the muscle-adipose index into cTNM has the same prognostic performance as the pTNM staging system. Chemotherapy-benefit analysis showed that stage II/III patients in the muscle-adipose balanced group could benefit from adjuvant chemotherapy.

CONCLUSIONS

The preoperative muscle-adipose index discovered for the first time is a new independent prognostic factor that affects the prognosis with GC. In addition, the preoperative muscle-adipose index is better than traditional nutrition and body composition indicators in terms of the prognostic evaluation of GC patients and the predictive value of recurrence risk.

Risk factors and clinical outcomes of postgastrectomy sarcopenia newly developed after curative resection for gastric cancer

This study aimed to investigate the risk factors and clinical impact of newly developed sarcopenia after surgical resection on the prognosis of patients undergoing curative gastrectomy for gastric cancer (GC).The clinicopathological data of 573 consecutive patients with GC who underwent curative gastrectomy were reviewed. Their skeletal muscle mass and abdominal fat volume were measured using abdominal computed tomography.Forty six of them (8.0%) were diagnosed with preoperative sarcopenia. Among the 527 patients without sarcopenia, 57 (10.8%) were diagnosed with postgastrectomy sarcopenia newly developed 1 year after curative gastrectomy. Female sex, weight loss, proximal location of the tumor and differentiated tumor were significant risk factors of postgastectomy sarcopenia newly developed after curative gastrectomy. There was a significant difference in the 5-year overall survival among the preoperative sarcopenic, nonsarcopenic, and postgastrectomy sarcopenic groups (P = .017). Especially, there was a significant difference between nonsarcopenic and postgastrectomy sarcopenic groups (P = .009). However, there was no significant difference in the 5-year disease-free survival among the groups (P = .49).Since newly developed sarcopenia after surgical resection had an influence on the overall survival, patients with high sarcopenia risks after curative gastrectomy may require early nutritional support.

Methodology, clinical applications, and future directions of body composition analysis using computed tomography (CT) images: A review

PURPOSE OF THE REVIEW

We aim to review the methods, current research evidence, and future directions in body composition analysis (BCA) with CT imaging.

RECENT FINDINGS

CT images can be used to evaluate muscle tissue, visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT) compartments. Manual and semiautomatic segmentation methods are still the gold standards. The segmentation of skeletal muscle tissue and VAT and SAT compartments is most often performed at the level of the 3rd lumbar vertebra. A decreased amount of CT-determined skeletal muscle mass is a marker of impaired survival in many patient populations, including patients with most types of cancer, some surgical patients, and those admitted to the intensive care unit (ICU). Patients with increased VAT are more susceptible to impaired survival / worse outcomes; however, those patients who are critically ill or admitted to the ICU or who will undergo surgery appear to be exceptions. The independent significance of SAT is less well established. Recently, the roles of the CT-determined decrease of muscle mass and increased VAT area and epicardial adipose tissue (EAT) volume have been shown to predict a more debilitating course of illness in patients suffering from severe acute respiratory syndrome coronavirus 2 (COVID-19) infection.

SUMMARY

The field of CT-based body composition analysis is rapidly evolving and shows great potential for clinical implementation.

A Novel Nutrition-Based Nomogram to Predict Prognosis After Curative Resection of Gastric Cancer

Objective: We sought to investigate the prognostic significance of body composition and weight change during the first 6 months of adjuvant chemotherapy after R0 resection and develop novel nomograms to accurately predict relapse-free survival (RFS) and overall survival (OS).

Methods: This retrospective study included 190 patients who underwent curative radical gastrectomy for gastric cancer and received adjuvant chemotherapy. The changes in weight and body composition including skeletal muscle index (SMI), subcutaneous adipose tissue (SAT), and visceral adipose tissue (VAT) were analyzed for 6 months. LASSO Cox regression and multivariate Cox regression were conducted to evaluate other clinical characteristics, which were used to construct a nomogram for the prediction of 3- and 5-year RFS and OS. The constructed nomogram was subjected to 1,000 resamples bootstrap for internal validation. The Concordance index (C-index) and time-dependent receiver operating characteristic (t-ROC) curves were used to evaluate and compare the discriminative abilities of the new nomograms, non-nutritional nomograms, and pTNM stage.

Results: The median follow-up duration was 42.0 (25.2–55.1) months. Factors included in the newly-built nomogram for RFS were pT stage, pN stage, tumor site, tumor size, nerve invasion or not, surgery type, and change of L3SMI, while factors included in the nomogram for OS were pT stage, pN stage, tumor size, nerve invasion or not, surgery type, and change of L3SMI. The C-index and t-ROC indicated that our newly-built nomograms had greater potential to accurately predict prognosis than the non-nutritional nomograms and pTNM stage system. Besides, oral nutritional supplements can reduce the degree of weight and L3SMI loss.

Conclusion: Change in skeletal muscle mass during adjuvant chemotherapy can be incorporated into predictive prognostic nomograms for RFS and OS in GC patients after radical resection. Dynamic changes in body composition and weight during adjuvant chemotherapy contribute to the early detection of poor outcomes.

Impact of subcutaneous and visceral fat adiposity in patients with colorectal cancer

BACKGROUND

Although different body composition including fat adiposity has known to be associated with survival in patients with colorectal cancer (CRC), the clinical significance was inconsistent. We investigated prognostic impact of visceral and subcutaneous fat adiposity in patients with CRC after surgical resection.

MATERIAL AND METHODS

This retrospective single center study included 987 stage I-III CRC patients (583 males, and 404 females) who underwent surgical resection between March 2005 and April 2014. Preoperative diagnostic computed tomography images were used to quantify visceral fat area (VFA) and subcutaneous fat area (SFA). The sex-specific optimal cut-off value for body fat composition was defined using the X-tile program. The Cox proportional hazards model was used to determine the correlation fat composition and disease-free survival (DFS). Harrell's concordance index (C-index) and integrated area under curve (iAUC) were used to evaluate the predictive ability of cut-derived stratification.

RESULTS

In univariate analysis, high SFA (≥141.73 cm² in males and ≥168.71 cm² in females) and high VFA (≥174.38 cm² in male and ≥83.65 cm² in female) were identified as significant prognostic factors for better DFS (p = .001 and p = .003 respectively). However, multivariate analysis revealed that high SFA independently predicted longer DFS (HR 0.505; 95% CI 0.266-0.957; p = .036) whereas, high VFA did not (HR 0.656; 95% CI 0.402-1.071; p = .092). Combining stage and SFA-cutoff showed better discriminatory performance than the model using stage solitary with respect to C-index (0.667; 95% CI 0.623-6.711; p = .0098) and iAUC (0.601; 95% CI 0.556-0.620).

CONCLUSION

High SFA was correlated with better DFS in patients with CRC. Subcutaneous fat can have additive predictive capability when incorporated into clinical decision-making.

Prognostic Value of Pretreatment Overweight/Obesity and Adipose Tissue Distribution in Resectable Gastric Cancer: A Retrospective Cohort Study

BACKGROUND

This is a study aimed at exploring the relationship between pretreatment overweight/obesity, adipose tissue distribution, and long-term prognosis of gastric cancer.

METHODS

A total of 607 gastric cancer patients were involved in the retrospective cohort study. Overweight/obese patients were defined as body mass index (BMI) greater than 25 kg/m2, and adipose tissue distribution parameters, including visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and VAT/SAT ratio were measured at the level of the third lumbar vertebra using computerized tomography images within 15 days before the surgery. Multiple Cox regression models were applied to evaluate the association between overweight/obesity and disease-specific survival (DSS) of gastric cancer, and covariates including age, gender, T stage, N stage, and chemotherapy were adjusted. Furthermore, multiple Cox regression models were performed to evaluate the association between adipose tissue distribution parameters and DSS of gastric cancer; except for covariates mentioned above, overweight/obesity was adjusted additionally.

RESULTS

Overweight/obesity was a predictive factor (HR = 0.61, 95% CI: 0.37-0.99) for the prognosis of gastric cancer. After additionally adjusting for overweight/obesity, high SAT percentage was an independent protective factor (HR = 0.59, 95% CI: 0.36-0.96), while high VAT percentage (HR = 1.68, 95% CI: 1.06-2.68) and high VAT/SAT ratio (HR = 1.99, 95% CI: 1.19-3.34) were independent risk factors for DSS of gastric cancer. Compared with other patients (overweight/obesity with low VAT/SAT ratio group, non-overweight/obesity or high VAT/SAT ratio group), patients in the non-overweight/obesity with high VAT/SAT ratio group had a worse prognosis (HR = 1.89, 95% CI: 1.28-2.77).

CONCLUSION

These results suggest that overweight/obesity is a predictive factor for the prognosis of gastric cancer. The VAT/SAT ratio could be used as a promising prognostic factor for gastric cancer. Therefore, in preoperative evaluation of gastric cancer patients, attention should be paid not only to BMI but also to adipose tissue distribution.

Association between Body Mass Index and Survival Outcome in Metastatic Cancer Patients Treated by Immunotherapy: Analysis of a French Retrospective Cohort

The response to immunotherapy has been little investigated in overweight and obese cancer patients. We evaluated the relationships between BMI, toxicity, and survival in patients treated by immunotherapy for metastatic cancer. We included metastatic cancer patients treated by immunotherapy between January 2017 and June 2020 at the Centre Léon Bérard. In total, 272 patients were included: 64% men and 36% women, with a median age of 61.4 years. BMI ≥ 25 in 34.2% and 50% had non-small cell lung cancer (n = 136). Most received monotherapy, with nivolumab in 41.9% and pembrolizumab in 37.9%. Toxicity, mostly dysthyroiditis, occurred in 41%. Median overall survival (OS), estimated by Kaplan-Meier analysis, was significantly longer for patients with a BMI ≥ 25 than for those with a BMI < 25 (24.8 versus 13.7 months HR = 0.63; 95% CI 0.44-0.92, p = 0.015), and for patients experiencing toxicity than for those without toxicity (NR versus 7.8 months, HR = 0.22; 95% CI 0.15-0.33, p < 0.001). Adjusted OS was associated with toxicity, and the occurrence of toxicity was associated with sex and histological features but not with BMI. Thus, being overweight and experiencing toxicity was associated with longer overall survival in patients treated by immunotherapy. More attention should be paid to body composition in the care of cancer patients.

Visceral-to-subcutaneous fat ratio independently predicts the prognosis of locally advanced gastric cancer----- highlighting the role of adiponectin receptors and PPARα, β/ δ, ɤ

BACKGROUND

Results of computed tomography body composition (CTBC) predicting long-term outcomes of gastric cancer have been mixed and the plausible mechanism remains elusive.

METHODS

We retrospectively enrolled a cohort of stage III gastric cancer who had undergone curative-intent gastrectomy. Clinicopathological variables, preoperative CTBC including abdominal muscle, subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT), and nutritional and inflammatory index were taken together to construct prognostic analysis. In vitro tests using co-culture system of gastric cancer cell lines and visceral adipocytes were conducted.

RESULTS

A total of 191 eligible patients were enrolled. By multivariate analysis, SAT and VAT/ SAT ratio were prognostic factors of disease-free survival, while sarcopenia was not. SAT remained as a prognostic factor of overall survival. SAT index was positively correlated with prognostic nutritional index, while VAT HU was positively correlated with platelet-to-lymphocyte ratio. Expression of adiponectin receptor 1 and 2 (AdipoR1, R2), and peroxisome proliferator-activated receptor (PPAR) α, β/δ, ɤ of patients with higher VAT/SAT ratio were decreased as compared to those with lower VAT/SAT ratio. Proliferation of gastric cancer cells co-cultured with adipocytes was increased by 50-100% and accompanied by down-regulation of mRNAs of AdipoR1, 2, PPARα, β/δ, ɤ, and pro-apoptotic genes, as compared to their controls.

CONCLUSION

SAT and VAT played exactly opposite prognostic roles of locally advanced gastric cancers, which might work through modulation of AdipoR1, 2 and PPARα, β/δ, ɤ. Preoperative CTBC, supplementary to classic TNM system, helps clinicians tailor individualized adjuvant therapy and/or nutritional support.

Abdominal subcutaneous fat quantification in obese patients from limited field-of-view MRI data

Different types of adipose tissue can be accurately localized and quantified by tomographic imaging techniques (MRI or CT). One common shortcoming for the abdominal subcutaneous adipose tissue (ASAT) of obese subjects is the technically restricted imaging field of view (FOV). This work derives equations for the conversion between six surrogate measures and fully segmented ASAT volume and discusses the predictive power of these image-based quantities. Clinical (gender, age, anthropometry) and MRI data (1.5 T, two-point Dixon sequence) of 193 overweight and obese patients (116 female, 77 male) from a single research center for obesity were analyzed retrospectively. Six surrogate measures of fully segmented ASAT volume (V_ASAT) were considered: two simple ASAT lengths, two partial areas (A_p-FH, A_p-ASIS) and two partial volumes (V_p-FH, V_p-ASIS) limited by either the femoral heads (FH) or the anterior superior iliac spine (ASIS). Least-squares regression between each measure and V_ASAT provided slope and intercept for the computation of estimated ASAT volumes (V^~_ASAT). Goodness of fit was evaluated by coefficient of determination (R²) and standard deviation of percent differences (s_d%) between V^~_ASAT and V_ASAT. Best agreement was observed for partial volume V_p-FH (s_d% = 14.4% and R² = 0.78), followed by V_p-ASIS (s_d% = 18.1% and R² = 0.69) and AWF_ASIS (s_d% = 23.9% and R² = 0.54), with minor gender differences only. Other estimates from simple lengths and partial areas were moderate only (s_d% > 23.0% and R² < 0.50). Gender differences in R² generally ranged between 0.02 (d_ven) and 0.29 (A_p-FH). The common FOV restriction for MRI volumetry of ASAT in obese subjects can best be overcome by estimating V_ASAT from V_p-FH using the equation derived here. The very simple AWF_ASIS can be used with reservation.

Severe loss of visceral fat and skeletal muscle after chemotherapy predicts poor prognosis in metastatic gastric cancer patients without gastrectomy

Background: The influence of body composition parameters in cancer prognosis attracted researchers' attention. This study investigated the role of visceral fat and skeletal muscle in the prognosis and efficacy of chemotherapy in metastatic gastric cancer (MGC). Methods: This study included MGC patients without gastrectomy treated with EOF regimen (epirubicin, oxaliplatin and fluorouracil), who participated in a Phase II clinical trial (NCT00767377) with available PACS image data. The visceral fat area (VFA) and skeletal muscle area (SMA) were measured using standard computed tomography (CT). Results: A total of 46 patients were enrolled in the study. Patients with low baseline VFA and SMA had significantly shorter PFS and OS. In addition, the loss of VFA and SMA also predicts significantly shorter PFS and OS. A prognostic index that included two risk factors, severe loss of VFA and SMA, was used to categorize the patients into two groups: good-risk group (0 risk factors), poor-risk group (1 or 2 risk factors). Compared with the good-risk group, the poor-risk group displayed a 3.562-fold-increased risk of progression [hazard ratio (HR) 3.652, 95 % CI 1.653-7.678; P =0.001] and 2.859-fold-increased risk of death [hazard ratio (HR) 2.859, 95 % CI 1.271-6.434; P =0.011]. Conclusion: Low baseline VFA and SMA, as well as the severe loss of VFA and SMA predict poor prognosis for MGC patients treated by EOF regimen. In patients with severe loss of VFA and/or SMA after 2-cycle chemotherapy, the decision of subsequent chemotherapy should be made after deliberate consideration.

Associations of Abdominal Skeletal Muscle Mass, Fat Mass, and Mortality among Men and Women with Stage I-III Colorectal Cancer

BACKGROUND

The associations of abdominal skeletal muscle mass index (SMI), visceral and subcutaneous adipose tissue (VAT and SAT, respectively), and mortality among patients with stage I-III colorectal cancer may differ for men and women, but only few studies stratified their data into men and women. We investigated associations of abdominal SMI, VAT, and SAT with overall mortality among men and among women with stage I-III colorectal cancer.

METHODS

SMI, VAT, and SAT were assessed from abdominal CT images for 1,998 patients with stage I-III colorectal cancer diagnosed between 2006 and 2015. Restricted cubic splines (RCS) were used to investigate associations of SMI, VAT, and SAT with overall mortality.

RESULTS

Average age of the participants was 67.9 ± 10.6 years and 58% were men. During a median follow-up of 4.3 years, 546 (27%) patients died. Among men, the association of SMI and mortality was statistically significant in a nonlinear way in the RCS analyses, with lower SMI levels associated with higher mortality. SMI was not associated with mortality among women. SAT was associated with mortality in a nonlinear way for men and for women, with lower SAT levels being associated with higher mortality. VAT was not significantly associated with mortality in men or women.

CONCLUSION

Associations of abdominal skeletal muscle mass with mortality among patients with colorectal cancer were not the same for men and for women.

IMPACT

This study stresses the importance for more attention on sex-related differences in body composition and cancer outcomes.

Postoperative BMI Loss at One Year Correlated with Poor Outcomes in Chinese Gastric Cancer Patients

Purpose: The present study focused on the long-term prognostic value of dynamic body mass index (BMI) change in gastric cancer patients who underwent gastrectomy. Methods: Clinical data from a total of 576 gastric cancer patients who underwent radical gastrectomy were collected. Univariate and multivariate analyses were performed to demonstrate the association between dynamic BMI variables (BMI before surgery, 1 month, 6 months or 12 months after surgery) and prognosis (DFS and OS). The correlation between BMI loss after surgery and survival outcomes was also evaluated. Results: Post-operative BMI, especially BMI at one year after surgery (p<0.001), was an independent risk factor of recurrence and mortality, wherein patients with high-BMI (≥23) showed significantly better outcomes than patients with normal-BMI (18.5-23) (DFS, HR:0.49; 95% CI:0.31-0.78; OS, HR:0.30; 95% CI: 0.15-0.59). On the contrary, low-BMI (<18.5) patients presented with worse outcomes (DFS, HR: 1.34; 95% CI: 1.00-1.80; OS, HR: 1.68; 95% CI: 1.20-2.34). In addition, compared with moderate BMI loss (≤10%), severe postoperative BMI loss (>10%) at one year was independently associated with substantially worse prognosis for DFS (HR: 1.54; 95% CI: 1.15-2.08) and OS (HR: 1.45; 95% CI: 1.02-2.06). Subgroup analysis indicated that gender (p=0.03), extent of resection (p<0.001), tumor site (p=0.001) and perineural invasion (p=0.007) were associated with postoperative BMI loss at one year. The prognostic value of postoperative BMI loss at one year was consistent among most clinicopathological subgroups, except for tumor site (interaction p=0.025 for OS). Conclusion: In Chinese gastric cancer patients who underwent gastrectomy, higher postoperative BMI (≥ 23) was significantly associated with longer survival time, whereas severe BMI loss (>10%) at one year after surgery was associated with worse outcomes. Thus, body weight maintenance after treatment is important, and dynamic monitoring of body weight and nutritional status should be emphasized in clinical practice.

CT-assessed sarcopenia is a predictive factor for both long-term and short-term outcomes in gastrointestinal oncology patients: a systematic review and meta-analysis

BACKGROUND

The impact of sarcopenia on the outcome of gastrointestinal (GI) oncological patients is still controversial. We aim to discuss the prevalence of sarcopenia and its relation to the oncological outcome.

METHODS

Embase, Medline, PubMed, and the Cochrane library were systematically searched for related keywords. Studies using CT to assess sarcopenia and evaluate its relationship with the outcome of GI oncological patients were included. Long-term outcomes, including overall survival and disease-free survival, were compared by hazard ratios (HRs) with 95% confidence intervals (CIs). Short-term outcomes, including total complications and major complications (Clavien-Dindo ≥IIIa) after curable surgery, were compared by the risk ratio (RR) and 95% CI.

RESULTS

A total of 70 studies including 21,875 patients were included in our study. The median incidence of sarcopenia was 34.7% (range from 2.1 to 83.3%). A total of 88.4% of studies used skeletal muscle index (SMI) in the third lumbar level on CT to define sarcopenia, and a total of 19 cut-offs were used to define sarcopenia. An increasing trend was found in the prevalence of sarcopenia when the cut-off of SMI increased (β = 0.22, 95% CI = 0.12-0.33, p < 0.001). The preoperative incidence of sarcopenia was associated both with an increased risk of overall mortality (HR = 1.602, 95% CI = 1.369-1.873, P < 0.001) and with disease-free mortality (HR = 1.461, 95% CI = 1.297-1.646, P < 0.001). Moreover, preoperative sarcopenia was a risk factor for both total complications (RR = 1.188, 95% CI = 1.083-1.303, P < 0.001) and major complications (RR = 1.228, 95% CI = 1.042-1.448, P = 0.014).

CONCLUSION

The prevalence of sarcopenia depends mostly on the diagnostic cut-off points of different criteria. Preoperative sarcopenia is a risk factor for both long-term and short-term outcomes.

The Importance of Body Composition in Explaining the Overweight Paradox in Cancer-Counterpoint

Despite a greater risk of cancer associated with higher BMI, overweight (BMI 25-<30 kg/m²) and class I obese (BMI 30-<35 kg/m²) patients often have a paradoxically lower risk of overall mortality after a cancer diagnosis, a phenomenon called the "obesity paradox." Only when patients exceed a BMI ≥35 kg/m² are elevations in mortality risk consistently noted. This paradox has been dismissed as the result of methodologic bias, which we will describe and debate here. However, even if such bias influences associations, there is growing evidence that body composition may in part explain the paradox. This phenomenon may more accurately be described as a BMI paradox. That is, BMI is a poor proxy for adiposity and does not distinguish muscle from adipose tissue, nor describe adipose tissue distribution. Low muscle mass is associated with higher risk of recurrence, overall and cancer-specific mortality, surgical complications, and treatment-related toxicities. Patients with who are overweight or obese have on average higher levels of muscle than their normal-weight counterparts. Also, there is some evidence that patients with moderate levels of subcutaneous adipose tissue may have lower mortality. More research utilizing body composition is needed to clarify the effects of adiposity on cancer mortality. Cancer Res; 78(8); 1906-12. ©2018 AACR.

The Plausibility of Obesity Paradox in Cancer-Point

In contrast to the convincing evidence that obesity (measured by body mass index, BMI) increases the risk of many different types of cancer, there is an ambiguity in the role of obesity in survival among cancer patients. Some studies suggested that higher BMI decreased mortality risk in cancer patients, a phenomenon called the obesity paradox. The spurious positive association between BMI and cancer survival is likely to be explained by several methodologic limitations including confounding, reverse causation, and collider stratification bias. Also, the inadequacy of BMI as a measure of body fatness in cancer patients commonly experiencing changes in body weight and body composition may have resulted in the paradox. Other factors contributing to the divergent results in literature are significant heterogeneity in study design and method (e.g., study population, follow-up length); time of BMI assessment (pre-, peri-, or post-diagnosis); and lack of consideration for variability in the strength and directions of associations by age, sex, race/ethnicity, and cancer subtype. Robust but practical methods to accurately assess body fatness and body compositions and weight trajectories in cancer survivors are needed to advance this emerging field and to develop weight guidelines to improve both the length and the quality of cancer survival. Cancer Res; 78(8); 1898-903. ©2018 AACR.

Marked Loss of Muscle, Visceral Fat, or Subcutaneous Fat After Gastrectomy Predicts Poor Survival in Advanced Gastric Cancer: Single-Center Study from the CLASSIC Trial

BACKGROUND

There is increasing interest in the influence of body composition on oncological outcomes. We evaluated the role of skeletal muscle and fat among patients with gastric cancer (GC) who underwent gastrectomy with or without adjuvant chemotherapy, as well as those changes' associations with survival outcomes.

METHODS

The present study evaluated 136 patients with GC who were enrolled in the CLASSIC Trial at Yonsei Cancer Center. Baseline body compositions including skeletal muscle area, Hounsfield units (HU), visceral fat area, and subcutaneous fat area were measured by preoperative computed tomography (CT). CT before and after the gastrectomy were used to determine the 6-month relative changes in body composition parameters. Continuous variables were dichotomized according to the best cutoff values by Contal and O'Quigley method.

RESULTS

Seventy-three patients (53.7%) underwent surgery alone, and 63 patients (46.3%) underwent surgery followed by adjuvant chemotherapy. The baseline body composition parameters were not associated with disease-free survival (DFS) or overall survival (OS). Except for the HU, the marked loss of muscle, visceral fat, or subcutaneous fat significantly predicted shorter DFS and OS. Patients with a marked loss in at least one significant body composition parameter had significantly shorter DFS (hazard ratio 2.9, 95% confidence interval 1.7-4.8, P < 0.001) and OS (hazard ratio 2.9, 95% confidence interval 1.7-5.0, P < 0.001).

CONCLUSIONS

Marked loss in body composition parameters significantly predicted shorter DFS and OS among patients with GC who underwent gastrectomy. Postoperative nutrition and active healthcare interventions could improve the prognosis of these GC patients.

The Obesity Paradox in Cancer: How Important Is Muscle?

Although higher body mass index (BMI) increases the incidence of many cancers, BMI can also exhibit a null or U-shaped relationship with survival among patients with existing disease; this association of higher BMI with improved survival is termed the obesity paradox. This review discusses possible explanations for the obesity paradox, the prevalence and consequences of low muscle mass in cancer patients, and future research directions. It is unlikely that methodological biases, such as reverse causality or confounding, fully explain the obesity paradox. Rather, up to a point, higher BMI may truly be associated with longer survival in cancer patients. This is due, in part, to the limitations of BMI, which scales weight to height without delineating adipose tissue distribution or distinguishing between adipose and muscle tissue. Thus, cancer patients with higher BMIs often have higher levels of protective muscle. We assert that more precise measures of body composition are required to clarify the relationship of body size to cancer outcomes, inform clinical decision-making, and help tailor lifestyle interventions.

Automatic Measurement of the Total Visceral Adipose Tissue From Computed Tomography Images by Using a Multi-Atlas Segmentation Method

BACKGROUND

The visceral adipose tissue (VAT) volume is a predictive and/or prognostic factor for many cancers. The objective of our study was to develop an automatic measurement of the whole VAT volume using a multi-atlas segmentation (MAS) method from a computed tomography.

METHODS

A total of 31 sets of whole-body computed tomography volume data were used. The reference VAT volume was defined on the basis of manual segmentation (VATMANUAL). We developed an algorithm, which measured automatically the VAT volumes using a MAS based on a nonrigid volume registration algorithm coupled with a selective and iterative method for performance level estimation (SIMPLE), called VATMAS_SIMPLE. The results were evaluated using intraclass correlation coefficient and dice similarity coefficients.

RESULTS

The intraclass correlation coefficient of VATMAS_SIMPLE was excellent, at 0.976 (confidence interval, 0.943-0.989) (P < 0.001). The dice similarity coefficient of VATMAS_SIMPLE was also good, at 0.905 (SD, 0.076).

CONCLUSIONS

This newly developed algorithm based on a MAS can measure accurately the whole abdominopelvic VAT.

Esophageal adenocarcinoma microenvironment: Peritumoral adipose tissue effects associated with chemoresistance

Peritumoral microenvironment affects cancer development and chemoresistance, and visceral adipose tissue may play a critical role. We aimed to identify depot‐specific adipose characteristics associated with carcinogenesis and resistance to neoadjuvant therapy in esophageal adenocarcinoma (EAC). We analyzed: (i) the peritumoral adipose tissue of rats following the induction of esophageal carcinogenesis; (ii) the peritumoral and distal (omental) adipose tissue of patients affected by EAC; (iii) adipose‐derived stem cells (ADSC) isolated from healthy patients and treated with conditioned medium (CM), collected from tumoral and adipose tissue of patients with EAC. In peritumoral adipose tissue of rats, CD34, CD31 and vascular endothelial growth factor (VEGF) expression increased progressively during EAC development. In patients with EAC, expression of CD34, CD45, CD90 and nucleostemin (NSTM) was higher in peritumoral than in distal adipose tissue and decreased in the presence of neoadjuvant therapy. Moreover, expression of NSTM, octamer‐binding transcription factor 4 (OCT‐4) and VEGF was higher in peritumoral (but not in distal) adipose tissue of chemoresistant patients. In ADSC, treatment with peritumoral adipose tissue CM increased the adipogenic potential and the expression of CD34, CD90, NSTM and OCT‐4. These effects were similar to those induced by cancer‐derived CM, but were not observed in ADSC treated with distal adipose tissue CM and were partially reduced by a leptin antagonist. Last, ADSC treated with peritumoral CM of chemoresistant patients displayed increased expression of NSTM, OCT‐4, leptin, leptin receptor, alpha‐smooth muscle actin (α‐SMA), CD34 and VEGF. These results suggest that peritumoral adipose tissue may promote, by paracrine signaling, the expression of depot‐specific factors associated with therapeutic resistance.

Body Composition as a Prognostic Factor of Neoadjuvant Chemotherapy Toxicity and Outcome in Patients with Locally Advanced Gastric Cancer

Purpose

Neoadjuvant chemotherapy has been shown to improve survival in locally advanced gastric cancer, but it is associated with significant toxicity. Sarcopenia and sarcopenic obesity have been studied in several types of cancers and have been reported to be associated with higher chemotherapy toxicity and morbi-mortality. The aim of this study was to assess the prevalence of sarcopenia/sarcopenic obesity in patients with gastric cancer, as well as its association with chemotherapy toxicity and long-term outcomes.

Materials and Methods

A retrospective analysis was performed using an academic cancer center patient cohort diagnosed with locally advanced gastric cancer between January 2012 and December 2014 and treated with neoadjuvant chemotherapy. We analyzed body composition (skeletal muscle and visceral fat index) in axial computed tomography images.

Results

A total of 48 patients met the inclusion criteria. The mean age was 68±10 years, and 33 patients (69%) were men. Dose-limiting toxicity was observed in 22 patients (46%), and treatment was terminated early owing to toxicity in 17 patients (35%). Median follow-up was 17 months. Sarcopenia and sarcopenic obesity were found at diagnosis in 23% and 10% of patients, respectively. We observed an association between termination of chemotherapy and both sarcopenia (P=0.069) and sarcopenic obesity (P=0.004). On multivariate analysis, the odds of treatment termination were higher in patients with sarcopenia (odds ratio=4.23; P=0.050). Patients with sarcopenic obesity showed lower overall survival (median survival of 6 months [95% confidence interval {CI}=3.9–8.5] vs. 25 months [95% CI=20.2–38.2]; log-rank test P=0.000).

Conclusions

Sarcopenia and sarcopenic obesity were associated with early termination of neoadjuvant chemotherapy in patients with gastric cancer; additionally, sarcopenic obesity was associated with poor survival.

Association of Weight Change after Colorectal Cancer Diagnosis and Outcomes in the Kaiser Permanente Northern California Population

BACKGROUND

Higher body mass index (BMI) is associated with incident colorectal cancer but not consistently with colorectal cancer survival. Whether weight gain or loss is associated with colorectal cancer survival is largely unknown.

METHODS

We identified 2,781 patients from Kaiser Permanente Northern California diagnosed with stages I-III colorectal cancer between 2006 and 2011 with weight and height measurements within 3 months of diagnosis and approximately 18 months after diagnosis. We evaluated associations between weight change and colorectal cancer-specific and overall mortality, adjusted for sociodemographics, disease severity, and treatment.

RESULTS

After completion of treatment and recovery from stage I-III colorectal cancer, loss of at least 10% of baseline weight was associated with significantly worse colorectal cancer-specific mortality (HR 3.20; 95% confidence interval [CI], 2.33-4.39; P_trend < 0.0001) and overall mortality (HR 3.27; 95% CI, 2.56-4.18; P_trend < 0.0001). For every 5% loss of baseline weight, there was a 41% increased risk of colorectal cancer-specific mortality (95% CI, 29%-56%). Weight gain was not significantly associated with colorectal cancer-specific mortality (P_trend = 0.54) or overall mortality (P_trend = 0.27). The associations were largely unchanged after restricting analyses to exclude patients who died within 6 months and 12 months of the second weight measurement. No significant interactions were demonstrated for weight loss or gain by gender, stage, primary tumor location, or baseline BMI.

CONCLUSIONS

Weight loss after diagnosis was associated with worse colorectal cancer-specific mortality and overall mortality. Reverse causation does not appear to explain our findings.

IMPACT

Understanding mechanistic underpinnings for the association of weight to worse mortality is important to improving patient outcomes. Cancer Epidemiol Biomarkers Prev; 26(1); 30-37. ©2016 AACR SEE ALL THE ARTICLES IN THIS CEBP FOCUS SECTION, "THE OBESITY PARADOX IN CANCER EVIDENCE AND NEW DIRECTIONS".

Obesity and Energy Balance in GI Cancer

The prevalence of overweight (body mass index [BMI], 25 to 29.9 kg/m2) and obesity (BMI ≥ 30 kg/m2) have increased dramatically in the United States. Because increasing BMI is associated with the development of multiple different cancer types, including most GI cancers, providers will frequently encounter patients with GI cancer who are overweight or obese. Mounting evidence associates overweight and/or obesity with worsened prognosis in multiple GI cancers, including esophageal, gastric, hepatocellular, pancreatic, and colorectal. However, these data are observational and may be subject to bias and/or confounding. Furthermore, in some cancer types, the associations between BMI and outcomes is not linear, where overweight and class I obese patients may have an improvement in outcome. This report provides a brief highlight of existing studies that have linked overweight and/or obesity to prognosis in GI cancer; provides recommendations on best management practices; and discusses limitations, controversies, and future directions in this rapidly evolving area. There are multiple areas of promise that warrant continued investigation: What are the comparative contributions of energy balance, including weight, dietary patterns, and physical activity on cancer prognosis? What are the specific physiologic pathways that mediate the relationship between energy balance and prognosis? What is the relationship between low muscle mass (sarcopenia) or sarcopenic obesity and cancer prognosis? Are there subsets of patients for whom purposefully altering energy balance would be deleterious to prognosis? This area is rich with opportunities to understand how states of energy (im)balance can be favorably altered to promote healthy survivorship.

Visceral adiposity and cancer survival: a review of imaging studies

Although obesity is a well-known risk factor for cancer, the association between obesity and cancer survival remains controversial. This is partially due to the inability of conventional obesity measures to directly assess adiposity or adipose tissue distribution. As a metabolic organ, visceral adipose tissue (VAT) secrets a variety of cytokines and cytokine-like factors, potentially affecting cancer survival. The objective of this review was to investigate the influence of imaging-assessed VAT on cancer survival. A total of 22 studies assessing the impact of visceral adiposity on survival were included. Negative associations between VAT and survival were more frequently observed among patients with colorectal (four of six studies) and pancreatic (three of five studies) cancers, compared to higher VAT predicting longer survival in most studies of renal cell carcinoma patients (four of five studies). Methodological limitations, including unstandardised VAT measurement methods, lack of other body composition measurement (i.e. muscle mass), small sample size and heterogeneous cohort characteristics, may explain controversial findings related to the impact of VAT on cancer survival.