Prognostic significance of visceral obesity in patients with advanced renal cell carcinoma undergoing nephrectomy

Development of a CT-assessed adiposity nomogram for predicting outcome in localized ccRCC

PURPOSE

This study aimed to develop and validate a computed tomography-based nomogram assessing visceral and subcutaneous adiposity for predicting outcomes in localized clear cell renal cell carcinoma (ccRCC).

METHODS

A cohort of 364 patients with pathologically confirmed ccRCC participated in this retrospective study, with 254 patients assigned to the training set and 110 to the validation set (a 7:3 distribution ratio). The adipose score (AS) was generated using the least absolute shrinkage and selection operator Cox regression. Subsequently, a nomogram was constructed by integrating the clinical independent predictor with the AS to predict disease-free survival (DFS) in localized ccRCC after surgery. The performance of the nomogram was compared with the University of California, Los Angeles, Integrated Staging System (UISS), and the Stage, Size, Grade, and Necrosis (SSIGN) score.

RESULTS

In both the training and validation cohorts, the nomogram exhibited superior discrimination compared to SSIGN and UISS (C-index: 0.897 vs. 0.781 vs. 0.776 in the training cohort, and 0.752 vs. 0.596 vs. 0.686 in the validation cohort; 5 year AUC: 0.907 vs. 0.805 vs. 0.820 in the training cohort, and 0.832 vs. 0.577 vs. 0.726 in the validation cohort). Decision curve analysis (DCA) revealed a superior net benefit across a wider range of threshold probabilities for predicting 5 year DFS compared to UISS and SSIGN scores.

CONCLUSIONS

The developed prognostic nomogram demonstrated high accuracy and overall superior performance compared to existing prognostic models.

A Multicenter Evaluation of Treatment-associated Changes in Body Composition in Men With Germ Cell Tumors of the Testis: Implications for Adverse Events and Complications

OBJECTIVE

To characterize changes in body composition following cytotoxic chemotherapy for germ cell carcinoma of the testis (GCT) and quantify associations between body composition metrics and chemotherapy-associated adverse events (AEs) and post-retroperitoneal lymph node dissection (RPLND) complications.

MATERIALS AND METHODS

This retrospective multi-center study included 216 men with GCT treated with cytotoxic chemotherapy and/or RPLND (2005-2020). We measured body composition including skeletal muscle (SMI), visceral adipose (VAI,), subcutaneous adipose (SAI), and fat mass (FMI) indices on computed tomography. We quantified chemotherapy-associated changes in body composition and evaluated associations between body composition and incidence of grade 3 + AEs and post-RPLND complications on multivariable logistic regression analyses.

RESULTS

One hundred and eighty-two men received a median of 3 cycles of cisplatin-based chemotherapy. Following chemotherapy, median change in SMI was -6% (P = <.0001), while VAI, SAI, and FMI increased by +13% (P = <.0001), +11% (P = <.0001), and +6% (P = <.0001), respectively. Seventy-nine patients (43%) experienced at least one grade 3 + AE. A decrease in SMI following chemotherapy was associated with increased risk of grade 3 + AEs (P = .047). One hundred and 3 men with a median age of 28.5 years (IQR 23-35.5) underwent RPLND of whom 22 (21.3%) experienced at least 1 grade 3 + post-RPLND complication. No baseline body composition metrics were associated with post-RPLND complications.

CONCLUSION

In men with GCT of the testis, chemotherapy was associated with 6% loss of lean muscle mass and gains in adiposity. Lower skeletal muscle was associated with a higher incidence of chemotherapy-associated AEs. Body composition was not associated with the incidence of post-RPLND complications.

Prognostic value of preoperative radiographic perinephric fat features in renal cell carcinoma patients undergoing surgery

BACKGROUND

We aimed to assess the prognostic importance of perinephric fat features in images of patients with non-metastatic renal cell carcinoma (RCC) undergoing surgery.

METHODS

We enrolled RCC patients who underwent surgical treatment between 2011 and 2019. Two characteristics, including perinephric fat thickness and perinephric fat stranding, were evaluated using preoperative computed tomography or magnetic resonance images. The association between perinephric fat characteristics and disease progression was examined by Kaplan-Meier survival analysis and Cox regression model.

RESULTS

In a multivariate Cox proportional hazards model adjusting for tumor stage, intratumoral necrosis, and neutrophil-to-lymphocyte ratio, we found that patients in the thin perinephric fat group (<1 cm) had a poorer progression-free survival (PFS) compared to the thick perinephric fat group (≥1 cm) (HR 2.8; 95% CI 1.175-6.674, p = 0.02). Additionally, the fat stranding group had a poorer PFS than the non-stranding group (HR 3.852; 95% CI 1.082-13.704, p = 0.037). The non-stranding with thick perinephric fat group exhibits the highest cumulative PFS while the stranding with thin perinephric fat group has the lowest cumulative PFS. In receiver operating characteristic curve analysis, combing these two perinephric fat characteristics with tumor stage can achieve a better discriminatory power than tumor stage alone.

CONCLUSIONS

Our study indicates that the evaluation of image-based perinephric fat features is a simple, straightforward, reproducible tool for predicting RCC prognosis and may assist in preoperative risk stratification.

A Review of the Paradigmatic Role of Adipose Tissue in Renal Cancer: Fat Measurement and Tumor Behavior Features

(1) Background: Renal-cell carcinoma (RCC) incidence has been steadily rising, with obesity identified as a potential risk factor. However, the relationship between obesity and RCC prognosis remains unclear. This systematic review aims to investigate the impact of different adipose tissue measurements on RCC behavior and prognosis. (2) Methods: A search of MEDLINE databases identified 20 eligible studies focusing on various fat measurements, including visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), perirenal adipose tissue (PRAT), and the Mayo adhesive probability (MAP) score. (3) Results: The review revealed conflicting findings regarding the association between adipose tissue measurements and RCC outcomes. While some studies suggested a protective role of certain fat deposits, particularly VAT, against disease progression and mortality, others reported contradictory results across different adipose metrics and RCC subtypes. (4) Conclusions: Methodological variations and limitations, such as retrospective designs and sample size constraints, pose challenges to standardization and generalizability. Further research is needed to understand these associations better and establish standardized approaches for adiposity assessment in RCC patients, which could inform clinical practice and therapeutic decision-making.

Prediction of Mortality and Hepatic Encephalopathy after Transjugular Intrahepatic Portosystemic Shunt Placement: Baseline and Longitudinal Body Composition Measurement

PURPOSE

To investigate effects of baseline and early longitudinal body composition changes on mortality and hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunt (TIPS).

MATERIALS AND METHODS

This is a case-control study with analysis of a TIPS registry (1995-2020) including data from patients with cirrhosis with computed tomography (CT) scans obtained within 1 month before and 3 months after TIPS. Core muscle area (CMA), macroscopic subcutaneous adipose tissue (mSAT), macroscopic visceral adipose tissue (mVAT) area, and muscle adiposity index (MAI) on CT were obtained. Multipredictor Cox proportional hazards models were used to assess the effect of body composition variables on mortality or HE.

RESULTS

In total, 280 patients (158 men; median age, 57.0 years; median Model for End-stage Liver Disease-sodium [MELD-Na] score, 14.0) were included. Thirty-four patients had post-TIPS imaging. Median baseline CMA was 68.3 cm2 (interquartile range, 57.7-83.5 cm2). Patients with higher baseline CMA had decreased risks of mortality (hazard ratio [HR]: 0.82; P = .04) and HE (HR: 0.82; P = .009). It improved prediction of mortality over MELD-Na and post-TIPS right atrial pressure alone (confidence interval = 0.729). An increase in CMA (HR: 0.60; P = .043) and mSAT (HR: 0.86; P = .022) or decrease in MAI (HR: 1.50; P = .049) from before to after TIPS was associated with a decreased risk of mortality. An increase in mSAT was associated with an increased risk of HE (HR: 1.11; P = .04).

CONCLUSIONS

CMA on CT scan 1 month before TIPS placement predicts mortality and HE in patients with cirrhosis. Changes in body composition on CT measured 3 months after TIPS placement independently predict mortality and HE.

Cohort profile - the Renal cell cancer: Lifestyle, prognosis and quality of life (ReLife) study in the Netherlands

PURPOSE

The Renal cell cancer: Lifestyle, prognosis and quality of life (ReLife) study is set up to obtain insight into the association of patient and tumour characteristics, lifestyle habits and circulating biomarkers with body composition features in patients with localised renal cell cancer (RCC). Further, it aims to assess the association of body composition features, lifestyle habits and circulating biomarkers with clinical outcomes, including health-related quality of life.

PARTICIPANTS

The ReLife study is a multicentre prospective cohort study involving 368 patients with newly diagnosed stages I-III RCC recruited from January 2018 to June 2021 from 18 hospitals in the Netherlands. At 3 months, 1 year and 2 years after treatment, participants fill out a general questionnaire and questionnaires about their lifestyle habits (eg, diet, physical activity, smoking and alcohol consumption), medical history and health-related quality of life. At all three time points, patients wear an accelerometer and have blood samples taken. CT scans for body composition analysis are being collected. Permission is asked for collection of tumour samples. Information about disease characteristics, treatment of the primary tumour and clinical outcomes is being collected from medical records by the Netherlands Cancer Registry.

FINDINGS TO DATE

A total of 836 invited patients were eligible and 368 patients were willing to participate and were included (response rate 44%). The mean age of patients was 62.5±9.0 years and 70% was male. The majority had stage I (65%) disease and were treated with radical nephrectomy (57%). Data collection at 3 months and 1 years after treatment have been finalised.

FUTURE PLANS

Data collection at 2 years after treatment is expected to be finalised in June 2023 and longitudinal clinical data will continue to be collected. Results of studies based on this cohort are important to develop personalised evidence-based lifestyle advice for patients with localised RCC to enable them to get more control over their disease course.

Sex Differences in Renal Cell Carcinoma: The Importance of Body Composition

PURPOSE

To examine sex-specific differences in renal cell carcinoma (RCC) in relation to abdominal fat accumulation, psoas muscle density, tumor size, pathology, and survival, and to evaluate possible associations with RCC characteristics and outcome.

METHODS

A total of 470 patients with RCC who underwent nephrectomy between 2006 and 2019 were included in this retrospective study. Specific characteristics of RCC patients were collected, including sex, height, tumor size, grade, and data on patient survival, if available. Abdominal fat measurements and psoas muscle area were determined at the level of L3 (cm²).

RESULTS

Women had a higher subcutaneous (p < 0.001) and men had a higher visceral fat area, relative proportion of visceral fat area (p < 0.001), and psoas muscle index (p < 0.001). Logistic regression analysis showed an association between higher psoas muscle index and lower grade tumors [women: odds ratio (OR) 0.94, 95% confidence interval (CI) 0.89-0.99, p = 0.011; men: OR 0.97 (95% CI, 0.95-0.99, p = 0.012]. Univariate regression analysis demonstrated an association between psoas muscle index and overall survival (women: OR 1.41, 95% CI 1.03-1.93, p = 0.033; men: OR 1.62 (95% CI, 1.33-1.97, p < 0.001). In contrast, there were no associations between abdominal fat measurements and tumor size, grade, or survival. Also, there were no sex-specific differences in tumor size or tumor grades.

CONCLUSIONS

A higher preoperative psoas muscle index was independently associated with overall survival in RCC patients, with a stronger association in men compared with women. In addition, the psoas muscle index showed an inverse association with tumor grade, whereby this association was slightly more pronounced in women than in men.

T-stage-specific abdominal visceral fat, haematological nutrition indicators and inflammation as prognostic factors in patients with clear renal cell carcinoma

Clear cell renal carcinoma (ccRCC) is the most common histological type of renal cancer and has the highest mortality. Several studies have been conducted on the relationship between adipose tissue and ccRCC prognosis, however, the results have been inconsistent to date. The current study aimed at establishing a link between abdominal fat composition and short-term prognosis in patients with ccRCC after T-stage stratification. We retrospectively analysed 250 patients with pathologically confirmed ccRCC (173 low T-stage and 77 high T-stage) in our hospital. The computed tomography (CT) images were evaluated using ImageJ. Then, subcutaneous and visceral fat areas (SFA and VFA), total fat areas (TFA) and the relative VFA (rVFA) were measured and computed. Meanwhile, biochemical indices of blood serum were analysed. The results showed that rVFA in low T-stage cohort who had a history of short-term postoperative complications were significantly lower than those who did not. No such association was observed in the high T-stage cohort. Further investigation revealed that the correlations between biochemical indexes and fat area-related variables varied across T-stage groups. As a result, rVFA is a reliable independent predictor of short-term prognosis in patients with low T-stage ccRCC but not in patients with high T-stage ccRCC.

A hint for the obesity paradox and the link between obesity, perirenal adipose tissue and Renal Cell Carcinoma progression

Increasing evidence supports a role for local fat depots in cancer outcomes. Despite the robust positive association of obesity with renal cell carcinoma (RCCa) diagnosis, increased adiposity is inversely related to RCCa oncological outcomes. Here, we sought to ascertain whether imagiologically assessed local fat depots associate with RCCa progression and survival and account for this apparent paradox. A retrospective cohort of renal carcinoma patients elective for nephrectomy (n = 137) were included. Beyond baseline clinicopathological characteristics, computed tomography (CT)-scans at the level of renal hilum evaluated areas and densities of different adipose tissue depots (perirenal, subcutaneous, visceral) and skeletal muscle (erector spinae, psoas and quadratus lumborum muscles) were analyzed. Univariate and multivariable Cox proportional hazards models were estimated following empirical analysis using stepwise Cox regression. Age, visceral adipose tissue (VAT) area and body mass index (BMI) predicted tumour-sided perirenal fat area (R² = 0.584), which presented upregulated UCP1 expression by 27-fold (P = 0.026) and smaller adipocyte areas, compared with subcutaneous depot. Multivariate analyses revealed that increased area of perirenal adipose tissue (PRAT) on the contralateral and tumour side associate with improved progression-free survival (HR = 0.3, 95CI = 0.1-0.8, P = 0.019) and overall survival (HR = 0.3, 95CI = 0.1-0.7, P = 0.009). PRAT measurements using CT, might become a possible tool, well correlated with other measures of obesity such as VAT and BMI, that will improve determination of obesity and contribute to assess the risk for disease progression and mortality in renal cancer patients. Present data supports the obesity paradox in RCCa, assumed that larger PRAT areas seem to protect from disease progression and death.

Association of visceral and subcutaneous adiposity with tumor stage and Fuhrman grade in renal cell carcinoma

Higher BMI has been associated with lower tumor stage and grade and improved survival in renal cell cancer (RCC). BMI cannot distinguish between visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). We examined associations of BMI, VAT, SAT, total adipose tissue (TAT) and relative VAT (rVAT) with tumor stage and grade in RCC patients. In a Dutch multicenter population-based historical cohort study 1039 RCC patients diagnosed between 2008 and 2012 were assessed for VAT and SAT using Computed Tomography images at L3. Sex-stratified multinomial logistic regression analyses were performed (linearly per 10-unit increase) between BMI, VAT, SAT, TAT and relative VAT (rVAT) with tumor stage and Fuhrman grade. Higher VAT, TAT and rVAT were associated with a lower risk of stage IV versus stage I in males (OR 0.93; 95%CI 0.91–0.96, OR 0.95; 95%CI 0.93–0.98, OR 0.97; 95%CI 0.96–0.99, respectively). Females showed similar associations, but only higher VAT was statistically significantly associated with reduced risk of stage IV (OR 0.95 95%CI 0.89–1.00). No associations with grade, SAT or BMI were found. In conclusion, higher VAT and TAT was associated with lower risk of stage IV RCC. This might be due to weight loss or cancer cachexia in stage IV patients.

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.

Utilizing Computed Tomography to Analyze the Morphomic Change between Patients with Localized and Metastatic Renal Cell Carcinoma: Body Composition Varies According to Cancer Stage

Background: This study aimed to elucidate the change of body composition in different clinical stages of renal cell carcinoma (RCC) by analyzing computed tomography (CT) images. Methods: We enrolled patients diagnosed with RCC in a tertiary medical center who did not mention body weight loss or symptoms of cachexia. We grouped patients into those with localized RCC and those with metastatic RCC. Analyses of the volume of skeletal muscles tissue (SMT), subcutaneous adipose tissue (SAT), and visceral adipose tissue (VAT) calculated based on CT images were performed and included subgroup analyses by sex and age. The correlation between tumor size and body composition in localized RCC was also examined. Results: A total of 188 patients were enrolled in this study. There was significantly lower VAT (p = 0.015) in the metastatic group than in the localized group. SAT, body weight, and body mass index (BMI) were not significantly different between these two groups. In the subgroup analysis, a significant difference in SMT and VAT was noted in the male and younger subgroups but not in the female and older subgroups. Regarding primary tumor size in localized RCC, VAT was significantly higher in patients with larger tumors (p = 0.003). Conclusions: In localized RCC, VAT volume was significantly larger in those with large primary tumor size. However, the VAT was significantly lower in those with metastatic status comparing to those with localized disease. The clinical course of cancers closely correlates with body composition.

Sarcopenia and systemic inflammation are associated with decreased survival after cytoreductive nephrectomy for metastatic renal cell carcinoma

BACKGROUND

This study was aimed at assessing the associations of sarcopenia, muscle density, adiposity, and inflammation with overall survival (OS) after cytoreductive nephrectomy (CN) for metastatic renal cell carcinoma.

METHODS

In all, 158 patients undergoing CN from 2001 to 2014 had digitized preoperative imaging for tissue segmentation via Slice-O-Matic software (version 5.0) at the mid-L3 level. The skeletal muscle index was calculated with the skeletal muscle area (cm² ) normalized for height (m² ), and the skeletal muscle density (SMD) was calculated with average Hounsfield units. Adiposity was measured with the cross-sectional area (cm² ) of visceral, subcutaneous, and intramuscular adiposity compartments and was similarly normalized for height. The average fat density was obtained in Hounsfield units. OS was estimated with the Kaplan-Meier method. Associations between body composition, inflammation metrics, and relevant clinicopathology and OS were assessed with univariable and multivariate Cox analyses.

RESULTS

Seventy-six of the 158 patients (48%) were sarcopenic. Sarcopenia was associated with elevated neutrophil to lymphocyte ratios (NLRs; P = .02), increased age (P = .001), lower body mass indices (P = .009), greater modified Motzer scores (P = .019), and lower SMD (P = .006). The median OS was 15.0 and 29.4 months for sarcopenic and nonsarcopenic patients, respectively (P = .04). Elevated inflammation (NLR or C-reactive protein), in addition to sarcopenia, was independently associated with OS, with an elevated NLR ≥ 3.5 and sarcopenia associated with the poorest OS at 10.2 months. No associations were observed between measurements of muscle density or adiposity and OS.

CONCLUSIONS

Sarcopenia and measures of high systemic inflammation are additively associated with inferior OS after CN and may be of use in preoperative risk stratification.

LAY SUMMARY

Body composition and sarcopenia (a deficiency in skeletal musculature) have been shown to affect outcomes in cancer. We found that sarcopenic patients had poor survival in comparison with nonsarcopenic patients in the setting of metastatic renal cell carcinoma (mRCC). Patients with both elevated inflammation and sarcopenia had the poorest survival. Sarcopenia is an objective measure of nutrition that can assist in therapeutic counseling and decision-making for individualized treatment in mRCC.

The value of sex-specific abdominal visceral fat as measured via CT as a predictor of clear renal cell carcinoma T stage

Although much is known about how adipose tissue affects the development of clear cell renal carcinoma (ccRCC), little information is available for the utility of sex-specific abdominal visceral fat composition as a predictor of clear cell renal carcinoma (ccRCC) T stage. We conducted CT-based sex-specific abdominal fat measurements in ccRCC patients to assess whether VFA distribution could predict the ccRCC T stage. In total, 253 patients (182 males and 71 females) from our hospital with pathologically confirmed ccRCC (178 low T-stage and 75 high T-stage) were retrospectively reviewed for the present study. Computed tomography (CT) scans were assessed using ImageJ to differentiate between the visceral and subcutaneous fat areas (VFA and SFA), after which the relative VFA (rVFA) and total fat area (TFA) were computed. The relationships between these fat area-related variables, patient age, sex, and BMI, and ccRCC T stage were then evaluated through univariate and multivariate logistic regression analysis to clarify the association between general or sex-specific abdominal visceral fat and T stage. Following adjustment for age, males with high T stage ccRCC exhibited an increased rVFA as compared to males with low T stage ccRCC, with the same relationship being observed among females. This association between rVFA and high T stage was confirmed through both univariate and multivariate models. As thus, sex-specific visceral fat composition is a reliable independent predictor that can identify both male and female patients with high T stage ccRCC.

Skeletal muscle radiodensity and visceral adipose tissue index are associated with survival in renal cell cancer - A multicenter population-based cohort study

INTRODUCTION

Body composition has been associated with disease outcome in several cancer types. Results for localized and metastatic renal cell cancer (RCC) are limited and inconsistent. Our aim was to examine the association between body composition and survival in RCC.

METHODS

We conducted a population-based historical cohort study including patients diagnosed with RCC from 2008 to 2012. Diagnostic Computed Tomography images at the third lumbar vertebra (L3) were assessed for skeletal muscle index (SMI), skeletal muscle density (SMD), visceral adipose tissue index (VATI) and subcutaneous adipose tissue index (SATI). Clinical data was retrieved from medical records. Multivariable Cox regressions with restricted cubic splines were used to determine hazard ratios (HRs) and 95% confidence intervals (95%CIs) for 10-unit increases in body composition features with overall survival (OS) and recurrence-free survival (RFS).

RESULTS

We included 719 stage I-III (of whom 254 (35.3%) died and 148 (21.9%) experienced recurrence) and 320 stage IV RCC patients (of whom 298 (93.1%) died). Median follow-up was 6.35 years (interquartile range; 1.41-8.23). For stage I-III, higher SMD was associated with better OS (men: HR 0.86; 95% CI 0.68-1.08; women: HR 0.69; 95% CI 0.50-0.95). Lower compared to median VATI was associated with worse OS for both men (HR 1.38; 95%CI 1.05-1.83 for VATI = 25) and women (HR 1.67; 95%CI 1.01-2.78 for VATI = 20). For stage IV, higher SMD and higher VATI were associated with better OS among men (HR 0.74; 95% CI 0.59-0.94 and HR 0.93; 95% CI 0.88-0.99, respectively). Results for women were similar but non-significant. No statistically significant associations were found for SMI or SATI.

CONCLUSION

Higher SMD and higher VATI were marginally associated with better survival in RCC patients and might be useful for better prognostication. However, the added value to current prognostic scores needs to be investigated.

Visceral fat is associated with high-grade complications in patients undergoing minimally invasive partial nephrectomy for small renal masses

Introduction:

Minimally invasive partial nephrectomy is standard of care treatment for small renal masses.

Objective:

We evaluated the relationship between subcutaneous and visceral obesity with high-grade postoperative 30-day complications in patients undergoing minimally invasive partial nephrectomy.

Methods:

We retrospectively identified 98 patients at our institution from 2014 to 2017 who underwent laparoscopic or robotic-assisted partial nephrectomy due to suspected renal cell carcinoma. Patients were stratified based on presence or absence of high-grade (Clavien ≥ IIIa) 30-day postoperative complications. Means were compared with the independent t test and proportions with chi-square analysis. Multivariate logistic regression was performed to determine independent predictors of high-grade 30-day complications.

Results:

Mean nephrometry score was 6.7 with 21 (21.4%) patients having hilar tumors. Mean estimation of blood loss was 207 mL, mean operating time was 223 min, and mean warm ischemia time was 23 min. The majority of patients had clear renal cell carcinoma (n = 83, 84.7%) and pT1a disease (n = 76, 77.6%) with negative margins (n = 89, 90.8%) on pathology. There were 5 (5.1%) patients who experienced a high-grade postoperative 30-day complication. Mean visceral fat index was an independent predictor of high-grade 30-day complications (odds ratio: 1.02; 95% confidence interval: 1.002–1.03; p = 0.027).

Conclusions:

Visceral obesity should be considered as a prognostic indicator of outcomes in patients undergoing surgical treatment for a small renal mass.

Impact of body composition on clinical outcomes in people with gastric cancer undergoing radical gastrectomy after neoadjuvant treatment

OBJECTIVES

The influence of body composition on clinical outcomes in individuals with gastric cancer (GC) undergoing radical gastrectomy after neoadjuvant treatment (NT) remains unclear. The purpose of this retrospective study was to investigate the association between body composition before NT or after NT and clinical outcomes in individuals with GC receiving multimodal treatments.

METHODS

This retrospective study included individuals with GC who received NT followed by radical gastrectomy between January 2016 and December 2018. Skeletal muscle, visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT) were measured by cross-sectional areas at the level of third lumbar vertebra based on single-slice computed tomography scan prior to NT and prior to the surgical operation. Sarcopenia, high VAT, and high SAT were defined using cutoff points of skeletal muscle index, visceral fat area, and subcutaneous fat area. Univariate and multivariate analyses were performed to evaluate risk factors of NT-related adverse events, postoperative complications and predictors of long-term survival.

RESULTS

A total of 110 individuals with GC were enrolled in this study. Sarcopenia was present in 62.7% of them before NT and in 56.4% after NT. Sarcopenia before NT was associated with more NT-related adverse events (odds ratio, 2.901; 95% confidence interval [CI], 1.205-6.983; P = 0.018). High VAT after NT (≥106 cm²) was associated with an increasing incidence of postoperative complications (odds ratio, 4.261; 95% CI, 1.332-13.632; P = 0.015). No body-composition parameter was relevant to tumor pathologic response to NT. As for long-term survival, poor overall survival was associated with both low VAT before NT (<120 cm²; hazard ratio [HR], 2.542; 95% CI, 1.111-5.817; P = 0.027) and low SAT after NT (<99.5 cm²; HR, 2.743; 95% CI, 1.248-6.027; P = 0.012). Similarly, shorter disease-free survival was associated with low VAT before NT (<120 cm²; HR, 2.502; 95% CI, 1.222-5.124; P = 0.012) and low VAT after NT (<106 cm²; HR, 2.505; 95% CI, 1.172-5.358; P = 0.018).

CONCLUSIONS

Body composition measured by computed tomography could predict NT-related adverse events, postoperative complications, and long-term survival in multimodal treatments for GC. More meaningfully, adipose-tissue status has significant prognostic value for individuals with advanced GC.

Visceral Adiposity as a Significant Predictor of Sunitinib-Induced Dose-Limiting Toxicities and Survival in Patients with Metastatic Clear Cell Renal Cell Carcinoma

Sunitinib is a first-line treatment for metastatic renal cell carcinoma (mRCC). Little is known about the predictive factors of sunitinib-induced dose-limiting toxicity (DLT) in Asian populations. We investigated whether body composition predicts sunitinib-induced DLT. We retrospectively reviewed sunitinib-treated Korean patients with clear cell mRCC from eight institutions. Body composition was measured using computed tomography. DLT was defined as any adverse event leading to dose reduction or treatment discontinuation. Univariate analysis was used to compare body composition indices, and logistic regression analyses were performed for factors predicting early DLT. Overall, 111/311 (32.5%) of patients experienced DLT. Significant differences were observed in the subcutaneous adipose tissue index (SATI; p = 0.001) and visceral adipose tissue index (VATI; p < 0.001) between patients with and without DLT. Multivariate analyses revealed that VATI (odds ratio: 1.013; p = 0.029) was significantly associated with early DLT. Additionally, 20% of patients who had a body mass index (BMI) greater than 23 kg/m² and a low VATI experienced DLT, whereas 34.3% of the remaining groups had DLT (p = 0.034). Significant differences were observed for median progression-free survival (13.0 vs. 26.0 months, respectively; p = 0.006) between patients with low and high VATI. Visceral adiposity was a significant predictor of sunitinib-associated DLT and survival. Patients with a low VATI and a BMI greater than 23 kg/m² experienced lower DLTs.

Prognostic Implication of Body Mass Index on Survival Outcomes in Surgically Treated Nonmetastatic Renal Cell Carcinoma: A Single-Institutional Retrospective Analysis of a Large Cohort

PURPOSE

Obesity is a well-known risk factor for renal cell carcinoma (RCC). However, the prognostic role of obesity in RCC has not been clearly established thus far. We aim to assess the effect of preoperative body mass index (BMI) on survival outcomes in nonmetastatic RCC patients.

PATIENTS AND METHODS

We retrospectively analyzed data on 2329 patients who underwent curative surgery for RCC between 2000 and 2014 in a single institution. Patients were divided into normal (< 23 kg/m²), overweight (23-24.9 kg/m²), and obese (≥ 25 kg/m²) groups depending on cutoffs for Asian population. Kaplan-Meier analysis with log-rank test was used to estimate and compare survival outcomes, including recurrence-free, overall, and cancer-specific survival, among each BMI group. The influence of BMI on each survival outcome was evaluated using multivariate Cox regression analyses.

RESULTS

Obese patients presented favorable 5-year recurrent-free (90.7% vs 84.9%, p < 0.001), overall (91.8% vs 86.8%, p = 0.002), and cancer-specific (94.8% vs 89.4%, p = 0.002) survival rates than the normal group. Multivariate analyses revealed that increasing BMI was an independent predictor of favorable survival outcomes (all p values < 0.05). In particular, overweight (p = 0.009) and obese (p = 0.009) patients showed better cancer-specific survival compared with normal patients.

CONCLUSIONS

Our data suggest that overweight and obesity defined based on BMI are generally related to favorable survival outcomes after surgery for RCC. Additional basic research is required to find out the biological mechanisms explaining the correlation between BMI and survival outcomes.

Clear cell renal cell carcinoma: the value of sex-specific abdominal visceral fat measured on CT for prediction of Fuhrman nuclear grade

OBJECTIVE

To explore whether sex-specific abdominal visceral fat composition on CT can predict the Fuhrman nuclear grade of clear cell renal cell carcinoma (ccRCC).

METHODS

One hundred seventy-one patients (123 males and 48 females) from four hospitals (multicentre group) and 159 patients (109 males and 50 females) from the cancer imaging archive (TCIA-KIRC group) with pathologically proven ccRCC (multicentre: 124 low grade and 47 high grade; TCIA-KIRC: 79 low grade and 80 high grade) were retrospectively included. Abdominal fat was segmented into subcutaneous fat area (SFA) and visceral fat area (VFA) on CT using ImageJ. The total fat area (TFA) and relative VFA (rVFA) were then calculated. Clinical characteristics (age, sex, waist circumference and maximum tumour diameter) were also assessed. Univariate and multivariate logistic regression analyses were performed to identify the association between general or sex-specific visceral fat composition and Fuhrman grade.

RESULTS

Females with high-grade ccRCC from the multicentre group had a higher rVFA (42.4 vs 31.3, p = 0.001) than those with low-grade ccRCC after adjusting for age. There was no significant difference in males. The rVFA remained a stable and independent predictor for females high-grade ccRCC in both the univariate (multicentre: OR 1.205, 95% CI 1.074-1.352, p = 0.001; TCIA-KIRC: OR 1.171, 95% CI 1.016-1.349, p = 0.029) and multivariate (multicentre: OR 1.095, 95% CI 1.024-1.170, p = 0.003; TCIA-KIRC: OR 1.103, 95% CI 1.024-1.187, p = 0.010) models.

CONCLUSIONS

Sex-specific visceral fat composition has different values for predicting high-grade ccRCC and could be used as an independent predictor for females with high-grade ccRCC.

KEY POINTS

• Visceral fat measurement (rVFA) as an independent predictor for high-grade ccRCC had good predictive power in females, but not in males. • Sex-specific visceral fat composition was significantly associated with high-grade ccRCC in females only. • The rVFA could be considered one of the risk factors for high-grade ccRCC for females.

The Prognostic Value of Body Fat Components in Metastasis Renal Cell Carcinoma Patients Treated with TKIs

Purpose

To assess the association between body fat components and survival status and tumor response for metastatic renal cell carcinoma (mRCC) patients treated with tyrosine kinase inhibitors (TKIs).

Patients and Methods

Patients with pathologically diagnosed and radiologically indicated mRCC were enrolled into the retrospective study. Three body fat components: total fat accumulation (TFA), visceral fat accumulation (VFA) and subcutaneous fat accumulation (SFA) were measured using standard CT scans. The clinical outcomes included progression-free survival (PFS), overall survival (OS), and tumor response rates. Univariate analysis and multivariate Cox proportion hazard regression models were used to find associated parameters and to calculate the adjusted hazard ratio (HR).

Results

A total of 146 patients were enrolled and the average age of patients was 56.5 years old. According to the univariate analysis, patients with an increased SFA and TFA had a longer PFS and OS. A similar phenomenon was observed among patients with ≥2 increasing body fat components about PFS and OS. As for multivariate analysis, SFA change (p=0.014) or the number of increasing body fat components (p=0.040) were independent indicators to predict PFS. In addition, SFA change (p=0.022) or the number of increasing body fat components (p=0.008) could independently predict OS. Moreover, a better disease control rate (p=0.028) was founded in patients with ≥2 increasing components. In the subgroup of patients with ≥2 metastasis sites, improved OS (p=0.017) and PFS (p=0.027) were found compared to those with <2 increasing components. Further multivariate analysis identified the number of increasing body fat components was an independent factor in predicting PFS (p=0.018) and OS (p=0.029).

Conclusion

Body fat accumulation, such as high SFA or TFA at progression, could improve the survival of patients with mRCC treated with TKIs, especially patients with higher tumor burden. It should be considered as an important parameter to predict the survival status of patients with mRCC.

Prognostic role of body composition parameters in gastric/gastroesophageal junction cancer patients from the EXPAND trial

BACKGROUND

Body fat and/or muscle composition influences prognosis in several cancer types. For advanced gastric and gastroesophageal junction cancer, we investigated which body composition parameters carry prognostic information beyond well-established clinical parameters using robust model selection strategy such that parameters identified can be expected to generalize and to be reproducible beyond our particular data set. Then we modelled how differences in these parameters translate into survival outcomes.

METHODS

Fat and muscle parameters were measured on baseline computed tomography scans in 761 patients with advanced gastric or gastroesophageal junction cancer from the phase III EXPAND trial, undergoing first-line chemotherapy. Cox regression analysis for overall survival (OS) and progression-free survival (PFS) included body composition parameters and clinical prognostic factors. All continuous variables were entered linearly into the model as there was no evidence of non-linear prognostic impact. For transferability, the final model included only parameters that were picked by Bayesian information criterion model selection followed by bootstrap analysis to identify the most robust model.

RESULTS

Muscle and fat parameters formed correlation clusters without relevant between-cluster correlation. Mean muscle attenuation (MA) clusters with the fat parameters. In multivariate analysis, MA was prognostic for OS (P < 0.0001) but not for PFS, while skeletal muscle index was prognostic for PFS (P = 0.02) but not for OS. Worse performance status Eastern Cooperative Oncology Group (ECOG 1/0), younger age (on a linear scale), and the number of metastatic sites were strong negative clinical prognostic factors for both OS and PFS. MA remained in the model for OS (P = 0.0001) following Bayesian information criterion model selection in contrast to skeletal muscle index that remained prognostic for PFS (P = 0.009). Applying stricter criteria for transferability, MA represented the only prognostic body composition parameter for OS, selected in >80% of bootstrap replicates. Finally, Cox model-derived survival curves indicated that large differences in MA translate into only moderate differences in expected OS in this cohort.

CONCLUSIONS

Among body composition parameters, only MA has robust prognostic impact for OS. Data suggest that treatment approaches targeting muscle quality are unlikely to prolong OS noticeably on their own in advanced gastric cancer patients, indicating that multimodal approaches should be pursued in the future.

Association of subcutaneous and visceral adipose tissue with overall survival in Taiwanese patients with bone metastases - results from a retrospective analysis of consecutively collected data

BACKGROUND

Growing evidence indicates that measures of body composition may be related to clinical outcomes in patients with malignancies. The aim of this study was to investigate whether measures of regional adiposity-including subcutaneous adipose tissue index (SATI) and visceral adipose tissue index (VATI)-can be associated with overall survival (OS) in Taiwanese patients with bone metastases.

METHODS

This is a retrospective analysis of prospectively collected data. We examined 1280 patients with bone metastases who had undergone radiotherapy (RT) between March 2005 and August 2013. Body composition (SATI, VATI, and muscle index) was assessed by computed tomography at the third lumbar vertebra and normalized for patient height. Patients were divided into low- and high-adiposity groups (for both SATI and VATI) according to sex-specific median values.

RESULTS

Both SATI (hazard ratio [HR]: 0.696; P<0.001) and VATI (HR: 0.87; P = 0.037)-but not muscle index-were independently associated with a more favorable OS, with the former showing a stronger relationship. The most favorable OS was observed in women with high SATI (11.21 months; 95% confidence interval: 9.434-12.988; P<0.001).

CONCLUSIONS

High SATI and VATI are associated with a more favorable OS in Taiwanese patients with bone metastases referred for RT. The question as to whether clinical measures aimed at improving adiposity may improve OS in this clinical population deserves further scrutiny.

Low Body Mass Index Is an Independent Prognostic Factor in Patients With Non-Small Cell Lung Cancer Treated With Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor

Background

Sarcopenia and obesity have been suspected as factors associated with efficacy of treatment and prognosis in various malignancies. This study aimed to investigate the association of pretreatment sarcopenia and visceral obesity with efficacy and prognosis of first- and second-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) for patients with non-small cell lung cancer (NSCLC) and positive EGFR mutation.

Methods

We retrospectively collected 167 NSCLC patients with mutant EGFR who had started EGFR-TKI monotherapy between October 2007 and August 2018 at our hospital. We classified 167 patients into two groups, according to the definition of underweight based on the World Health Organization (WHO) body mass index (BMI) classification and the Japanese sex-specific cut-off values of the following computed tomography (CT) images-assessed markers of pretreatment sarcopenia or visceral obesity, such as psoas muscle index (PMI), intramuscular adipose tissue content (IMAC) and visceral-to-subcutaneous fat ratio (VSR) at lumbar vertebra L3 level. We compared overall survival (OS) and progression-free survival (PFS) of two groups by Kaplan-Meier curves and log-rank tests. Using multivariate Cox proportional hazard analyses adjusted by age, neutrophil-to-lymphocyte ratio, performance status, EGFR mutation types and EGFR-TKI lines, and extra-pulmonary metastases or three or more than 3 metastatic sites, we searched independent prognostic factors of OS and PFS of EGFR-TKI therapy.

Results

The OS (median 26.0 vs. 32.3 months, P = 0.02) and PFS (9.1 vs. 14.8 months, P = 0.03) of patients with BMI < 18.5 were significantly shorter than those of patients with BMI ≥ 18.5. However, there was no significant difference in OS and PFS according to PMI, IMAC and VSR. The multivariate analyses detected only BMI < 18.5 as an unfavorable prognostic factor of shorter OS (hazard ratio (HR) 1.70, 95% confidence interval (CI) 1.03 - 2.81, P = 0.04) and PFS (HR 1.72, 95% CI 1.11 - 2.67, P = 0.02).

Conclusions

Pretreatment underweight was a significant prognostic factor of poor PFS and OS of EGFR-TKI therapy. However, neither pretreatment sarcopenia nor visceral obesity was associated with prognosis of EGFR-TKI. Underweight may be a surrogate for advanced disease burden.

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.

Preoperative Visceral Adiposity and Muscularity Predict Poor Outcomes after Hepatectomy for Hepatocellular Carcinoma

OBJECTIVE

Visceral adiposity, defined as a high visceral-to-subcutaneous adipose tissue area ratio (VSR), has been shown to be associated with poor outcomes in several cancers. However, in the surgical field, the significance of visceral adiposity remains controversial. The present study investigated the impact of visceral adiposity as well as sarcopenic factors (low muscularity) on outcomes in patients undergoing hepatectomy for hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

This retrospective study analyzed data from 606 patients undergoing hepatectomy for HCC at our institution between April 2005 and March 2016. Using preoperative plain computed tomography imaging at the level of the third lumbar vertebra, visceral adiposity, skeletal muscle mass, and muscle quality were evaluated by the VSR, skeletal muscle mass index (SMI), and intramuscular adipose tissue content (IMAC), respectively. The impact of these parameters on outcomes after hepatectomy for HCC was analyzed.

RESULTS

The overall survival rate was significantly lower among patients with a high VSR (p < 0.001) than among patients with a normal VSR. Similarly, the recurrence-free survival rate was significantly lower among patients with a high VSR (p = 0.016). A high VSR, low SMI, and high IMAC contributed to an increased risk of death (p < 0.001) and HCC recurrence (p < 0.001) in an additive manner. Multivariate analysis showed that not only preoperative low muscularity but also visceral adiposity was a significant risk factor for mortality (hazard ratio [HR] = 1.566, p < 0.001) and HCC recurrence (HR = 1.329, p = 0.020) after hepatectomy for HCC.

CONCLUSIONS

Preoperative visceral adiposity, as well as low muscularity, was closely related to poor outcomes after hepatectomy for HCC. It is crucial to establish a new strategy including perioperative nutritional interventions with rehabilitation for better outcomes after hepatectomy for HCC.

Synergy of Sex Differences in Visceral Fat Measured with CT and Tumor Metabolism Helps Predict Overall Survival in Patients with Renal Cell Carcinoma

Purpose To determine if sex differences in abdominal visceral fat composition, measured by using computed tomography (CT), and tumor glucose metabolism, measured by gene expression, can help predict outcomes in patients with clear cell renal cell carcinoma (RCC). Materials and Methods This retrospective cohort study included 222 patients with clear cell RCC from The Cancer Imaging Atlas. By using CT, body fat was segmented into subcutaneous fat and visceral fat areas (VFAs) and normalized to total fat to obtain the relative VFA (rVFA) and relative subcutaneous fat area. Multivariate Cox proportional hazard regression models were performed to identify effects of rVFA on sex-specific survival. Expression profiles for 39 glycolytic genes in tumors from these patients were obtained from The Cancer Genome Atlas to determine sex differences in metabolism and compared with rVFA. Key mutations in clear cell RCC were analyzed for association with rVFA and tumor glycolytic profiles. Results Women with rVFA greater than 30.9% had an increased risk of death (hazard ratio, 3.66 [95% confidence interval: 1.64, 8.19]) for women vs 1.13 ([95% confidence interval: 0.58, 2.18] for men, P = .028). Glycolytic gene expression stratified both men and women, and the combination of low rVFA and low glycolysis identified 19 women with excellent overall survival (P < .001). SETD2 and BAP1 mutations were uniquely enriched in female tumors with high glycolysis (P = .036 and .001, respectively). No significant differences were identified in tumor mutations between patients with high and low rVFA. Conclusion Sex differences in visceral fat and tumor glucose metabolism may provide a new risk-stratification system for patients with clear cell RCC. ^© RSNA, 2018 Online supplemental material is available for this article.

High perirenal fat thickness predicts a poor progression-free survival in patients with localized clear cell renal cell carcinoma

OBJECTIVES

The aim of the study was to assess the association between the progression-free survival (PFS) and perirenal fat thickness (PFT) in a population of histopathologically confirmed, localized clear cell renal cell carcinoma (ccRCC) patients.

METHODS

We retrospectively enrolled 174 patients with localized ccRCC at our center between December 2009 and December 2015. The preoperative visceral fat area (VFA), PFT, and subcutaneous fat area (SFA) were evaluated. Kaplan-Meier curves were used to assess the differences in PFS between the high and the low PFT groups within sexes. Potential independent prognostic factors of PFS were identified by univariable and multivariable Cox analyses.

RESULTS

During the follow-up period (median, 38 months), 27 patients (21 with high PFT and 6 with low PFT) experienced tumor progression. Kaplan-Meier curves revealed that high PFT was associated with a worse PFS than low PFT (P = 0.005). In the univariable Cox analyses, high VFA, high PFT, T stage, and the presence of sarcomatoid differentiation were significantly associated with a poor PFS. Moreover, both high PFT and VFA retained significance in the multivariable analysis.

CONCLUSION

We first report the evidence that high PFT presents as an independent risk factor of tumor progression in localized ccRCC. We suggest that this noninvasive and readily available preoperative parameter may help in the risk stratification of ccRCC patients before surgery.

Clinical implication of ectopic liver lipid accumulation in renal cell carcinoma patients without visceral obesity

Fatty liver has emerged as a prognostic marker of cancer, so we investigated the impact of ectopic lipid accumulation in liver on the clinical outcome for patients with renal cell carcinoma (RCC). The records of 230 consecutive patients who had undergone surgery for RCC were reviewed, and liver lipid accumulation was estimated from the attenuation in unenhanced preoperative CT images. The median liver CT values of patients with G3 tumors was lower than that of patients with G1-2 tumors (P = 0.0116), that of patients with pT3-4 tumors was lower than that of patients with pT1-2 tumors (P = 0.0336), and that of patients with visceral obesity defined as a visceral fat area ≥ 100 cm² was lower than that of patients without visceral obesity (P < 0.0001). In patients without visceral obesity the median liver CT values of patients with pT3-4 tumors was lower than that of patients with pT1-2 tumors (P = 0.0401), that of patients with metastasis was lower than that of patients without metastasis (P = 0.026), and fatty liver was associated with shorter overall survival (P = 0.0009). Ectopic lipid accumulation in liver thus seems to be a predictor of aggressive forms of RCC.

Sarcopenia Predicts Prognosis in Patients with Newly Diagnosed Hepatocellular Carcinoma, Independent of Tumor Stage and Liver Function

Purpose

The purpose of this study was to demonstrate the prognostic significance of changes in body composition in patients with newly diagnosed hepatocellular carcinoma (HCC).

Materials and Methods

Patients (n=178) newly diagnosed with HCC participated in the study between 2007 and 2012. Areas of skeletal muscle and abdominal fat were directly measured using a three-dimensional workstation. Cox proportional-hazards modes were used to estimate the effect of baseline variables on overall survival. The inverse probability of treatmentweighting (IPTW) method was used to minimize confounding bias.

Results

Cutoff values for sarcopenia, obtained from receiver-operating characteristic curves, were defined as skeletal muscle index at the third lumbar vertebra of ≤ 45.8 cm/m² for males and ≤ 43.0 cm/m² for females. Sarcopenia patients were older, more likely to be female, and had lower body mass index. Univariable analysis showed that the presence of sarcopenia and visceral to subcutaneous fat area ratio (VSR) were significantly associatedwith prognosis. The multivariable analyses revealed that VSR was predictive of overall survival. However, in the multivariable Cox model adjusted by IPTW, sarcopenia, not VSR, were associated with overall survival.

Conclusion

The presence of sarcopenia at HCC diagnosis is independently associated with survival.

The association between renal sinus fat area and the progression-free survival in Chinese non-metastatic clear-cell renal cell carcinoma patients

In this retrospective study, we evaluated the association between renal sinus fat area (RSFA) and survival in 268 Chinese non-metastatic clear-cell renal cell carcinoma (ccRCC) patients. Patients with high RSFA exhibited better progression-free survival than those with low RSFA in both univariable (HR: 0.240; 95% CI: 0.119–0.482; p < 0.001) and multivariable (HR: 0.432; 95% CI: 0.369–2.749; p = 0.027) analyses. A propensity-score matched (PSM) analysis using Kaplan-Meier curves confirmed our findings (log-rank test; p = 0.028). Based on the multivariable analysis, we constructed a prognostic nomogram with 4 factors, namely, RSFA, Fuhrman grade, AJCC stage and sarcomatoid component. The c-index values for the Leibovich scoring system and the nomogram were 0.762 (95%CI, 0.688–0.835) and 0.823 (95%CI, 0.759–0.888), respectively. These findings demonstrate that high RSFA is associated with better progression-free survival in non-metastatic ccRCC.

Clinical Investigation Into Plasma Neutrophil Gelatinase-Associated Lipocalin and Body Adipose Tissue Associated With Remaining Renal Function in Living Kidney Donor

OBJECTIVE

Plasma neutrophil gelatinase-associated lipocalin (pNGAL) is known to increase in proportion to the degree and period of renal damage. This study aimed to evaluate the clinical relevance of pNGAL and body adipose tissue to remaining renal function in living kidney donors.

METHODS

Between July 2013 and February 2015, 75 live kidney donors were enrolled. Visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and VAT/SAT ratio were measured in preoperative CT scan which performed before surgery. We analyzed the correlation among the variables (VAT, SAT, and VAT/SAT ratio), eGFR and pNGAL. ΔpNGAL-max(=Maximum pNGAL-measures), ΔpNGAL-min(=Minimum pNGAL-measures), ΔeGFR-max(=Maximum eGFR-measures) and ΔeGFR-min(=Minimum eGFR-measures) were also analyzed.

RESULTS

The highest value of pNGAL (207.46 ± 76 ng/mL) was observed on postoperative day 7, and the lowest value of eGFR (57.52 ± 11.20 mL/min/1.73 m²) was also measured on postoperative day 7. A significant correlation was found between ΔpNGAL, VAT, and VAT-to-SAT ratio. Moreover, a significant correlation between ΔpNGALmin and ΔeGFRmin was revealed. Also, VAT-to-SAT ratio was correlated with ΔeGFRmin during the all of the follow-up periods, and it was also correlated with ΔpNGALmin until postoperative day 3.

CONCLUSION

There was a correlation between the elevation of pNGAL until postoperative day 5 and the decrease of eGFR after living donor nephrectomy. VAT-to-SAT ratio had a significant correlation with both ΔpNGALmin and eGFRmin. Given the metabolism of pNGAL, the increase of pNGAL seemed to be affected as a consequence of body adipose tissue.

Impact of the Ratio of Visceral to Subcutaneous Adipose Tissue in Donor Nephrectomy Patients

OBJECTIVE

It was reported that a metabolic syndrome affected the remaining renal function after living donor nephrectomy. However, the measurement of waist circumference is unclear because it cannot distinguish between visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). We investigate the clinical correlation between body adipose tissue and renal function recovery after living donor nephrectomy.

METHODS

From July 2013 to February 2015, 75 living kidney donors were enrolled. The VAT and SAT were measured by preoperative computed tomography (CT) scan. Body mass index (BMI), VAT, SAT, and VAT-to-SAT ratio were analyzed according to a postoperative renal function recovery. Receiver operating characteristic (ROC) was performed to predict estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m² at postoperative 6 months for BMI, VAT, SAT, and VAT-to-SAT ratio.

RESULTS

The lowest value of eGFR (57.52 ± 11.20 mL/min/1.73 m²) was measured at postoperative day 7. There was no statistically significant difference in eGFR between 1 month and 3 months. BMI, VAT, SAT, and VAT-to-SAT ratio showed a statistically significant correlation with each other (Pearson correlation, P < .05). Also, the recovery time of eGFR was correlated with VAT-to-SAT ratio; it was significant at postoperative 1, 3, and 6 months. VAT-to-SAT ratio (0.654, 95% confidence interval 0.525-0.783, P = .024) had higher predictive value in ROC.

CONCLUSION

We developed a new variable to predict the value of lower eGFR (less than 60 mL/min/1.73 m²) at a postoperative 6 months in living kidney donor. According to a CT scan, VAT-to-SAT ratio can predict renal function recovery.

Subcutaneous adiposity is an independent predictor of mortality in cancer patients

BACKGROUND

Prognostic significance of adiposity, at the time of cancer diagnosis, on survival is not clear. Body mass index (kg m^-2) does not provide an appropriate assessment of body composition; therefore, the concept of the 'obesity paradox' needs to be investigated based on the prognostic significance of fat and muscle. Independent prognostic significance of adipose tissue in predicting mortality, importance of visceral and subcutaneous adiposity in the presence and absence of sarcopenia on survival, was investigated.

METHODS

Adiposity markers including total adipose index (TATI), visceral adipose tissue index (VATI) and subcutaneous adipose tissue index (SATI) were estimated for 1473 gastrointestinal and respiratory cancer patients and 273 metastatic renal cell carcinoma patients using computed tomography. Univariate and multivariate analysis to determine mortality hazard ratios (HR) were conducted using cox proportional hazard models.

RESULTS

Low SATI (SATI <50.0 cm² m^-2 in males and <42.0 cm² m^-2 in females) independently associated with increased mortality (HR: 1.26; 95% CI: 1.11-1.43; P<0.001) and shorter survival (13.1 months; 95% CI, 11.4-14.7) compared to patients with high SATI (19.3 months; 95% CI, 17.6-21.0; P<0.001). In the presence of sarcopenia, the longest survival was observed in patients with high subcutaneous adiposity.

CONCLUSIONS

Subcutaneous adipose tissues appear to associate with reduction in mortality risk demonstrating the prognostic importance of fat distribution. The effect of sarcopenia on survival was more pronounced in patients with low subcutaneous adiposity.

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.

The effect of visceral obesity on clinicopathological features in patients with endometrial cancer: a retrospective analysis of 200 Chinese patients

Background

To assess the effect of visceral adiposity on clinical and pathological characteristics in patients with endometrial cancer.

Methods

A retrospective review of medical documentation was performed in surgically treated endometrial cancer patients from January to November 2015 in our institution. The visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were measured at the level of umbilicus on single-slice computerized tomography. Visceral adiposity (VAT%) was calculated as VAT/(VAT + SAT).

Results

A total of 200 cases were included in the study. Median age at diagnosis was 54 years old. Most patients presented with early-stage tumor (86.0 % for I + II) and endometrioid histology (90.5 %). Positive lymph node occurred in 11.0 % (22/200) of the patients with the median number of retrieved nodes as 25 (range, 4–56). The entire population had a median body mass index (BMI) of 24.7 kg/m² and median VAT% of 31.89 %. BMI correlated with total adipose tissue (correlation coefficient = 0.667, P < 0.001), but not with VAT% (P = 0.495). Viscerally obese patients tended to be old and post-menopausal (P < 0.001; P = 0.003). Nodal metastasis and extrauterine disease were more commonly reported in patients with high VAT% (6.0 % vs. 16.0 %, P = 0.024; 9.0 % vs. 19.0 %, P = 0.042, respectively). Univariate and multivariate logistic regressions were performed to discern the contribution of variable factors on the lymph node metastasis. Grade (HR = 15.41, 95 % CI = 1.60–148.76; P = 0.018), lympho-vascular invasion (HR = 449.61, 95 % CI = 31.27–6463.93; P < 0.001) and high VAT% (HR = 6.37, 95 % CI = 1.42–28.69; P = 0.016) retained statistical significance for predicting lymph node metastasis.

Conclusions

Viscerally obese patients were more likely to be old and have positive lymph node as well as extrauterine disease. Grade, lympho-vascular invasion presence and visceral adiposity were predictors of nodal disease.

Renal cell carcinoma: links and risks

This review provides an overview of the incidence of renal cell carcinoma (RCC) and a summary of the most commonly associated risk factors. A literature review was performed with a focus on recent studies with a high level of evidence (large prospective cohort studies and meta-analyses). The incidence rate of RCC varies globally, with the rate rising rapidly in more developed regions, demonstrating the effects of increased use of diagnostic imaging and prevalence of modifiable risk factors. Based on the current evidence, cigarette smoking, obesity, and hypertension are the most well-established risk factors for sporadic RCC worldwide. Acquired cystic kidney disease is also a significant risk factor, specifically in dialysis patients. There is increasing evidence for an inverse association between RCC risk and moderate alcohol consumption. Certain analgesics and occupational exposure have been linked to an increased risk of RCC, although data are limited. Diets rich in fruits and vegetables may provide a protective effect.

Obesity and Kidney Cancer

Renal cell cancer (RCC) is the major type of kidney cancer with increasing incidence. Obesity is one of the well-established risk factors for RCC. Meta-analyses including multiple cohort and case-control studies have found a consistent positive association between obesity and RCC. The association appeared to be independent of other RCC risk factors including hypertension and has been often stronger in women, although a positive association has also been observed in men. Obesity has been largely measured as body mass index (BMI). Studies which evaluated other measures of obesity including waist circumference (WC), waist-to-hip ratio (WHR) as well as increase in weight have reported similar positive associations with RCC. Although the mechanisms by which obesity influences renal carcinogenesis have been under-explored, insulin resistance and certain growth factors including insulin-like growth factor (IGF-1), sex steroid hormones, and biochemical markers such as adiponectin may be involved. The positive association with obesity has been observed with the clear cell type of RCC, which is the major histological subtype. On the other hand, the association between obesity and RCC survival appears to be much more complex. An apparent inverse association between obesity at time of diagnosis and RCC survival has been observed in some studies' generating speculation of an "obesity paradox" hypothesis. However, this "paradox" may be due to reverse causation, selection bias, or other forms of bias rather than a true biological association.