Preoperative skeletal muscle index and visceral-to-subcutaneous fat area ratio are associated with long-term outcomes of elderly gastric cancer patients after gastrectomy

Establishment of a novel weight reduction model after laparoscopic sleeve gastrectomy based on abdominal fat area

In light of ongoing research elucidating the intricacies of obesity and metabolic syndrome, the role of abdominal fat (especially visceral fat) has been particularly prominent. Studies have revealed that visceral adipose tissue can accelerate the development of metabolic syndrome by releasing various bioactive compounds and hormones, such as lipocalin, leptin and interleukin. A retrospective analysis was performed on the clinical data of 167 patients with obesity. Among them, 105 patients who satisfied predefined inclusion and exclusion criteria were included. The parameters evaluated included total abdominal fat area (TAFA), laboratory indicators and anthropometric measurements. Weight reduction was quantified through percent total weight loss (%TWL) and percent excess weight loss (%EWL) postoperatively. Binary logistic regression analysis and receiver operating characteristic (ROC) curve analysis were employed to identify predictors of weight loss. Binary logistic regression analysis emphasized that total abdominal fat area was an independent predictor of %EWL ≥75% (p < 0.001). Total abdominal fat area (p = 0.033) and BMI (p = 0.003) were independent predictors of %TWL ≥30%. In our cohort, %TWL ≥30% at 1 year after surgery was closely related to the abdominal fat area and BMI. Based on these results, we formulated a novel model based on these factors, exhibiting superior predictive value for excellent weight loss.

Risk factors for abdominal surgical infectious complications after distal gastrectomy for gastric cancer: A post-hoc analysis of a randomized controlled trial (JCOG0912)

BACKGROUND

Abdominal surgical infectious complications (ASIC) after gastrectomy for gastric cancer impair patients' survival and quality of life. JCOG0912 was conducted to compare laparoscopy-assisted distal gastrectomy with open distal gastrectomy for clinical stage IA or IB gastric cancer. The present study aimed to identify risk factors for ASIC using prospectively collected data.

METHODS

We performed a post-hoc analysis of the risk factors for ASIC using the dataset from JCOG0912. All complications were evaluated according to the Clavien-Dindo classification (CD). ASIC was defined as CD grade I or higher anastomotic leakage, pancreatic fistula, abdominal abscess, and wound infection. Analyses were performed using the logistic regression model for univariable and multivariable analyses.

RESULTS

A total of 910 patients were included (median age, 63 years; male sex, 61 %). Among them, ASIC occurred in 5.8 % of patients. In the univariable analysis, male sex (odds ratio [OR] 2.855, P = 0.003), diabetes (OR 2.565, P = 0.029), and Roux-en-Y (R-Y) reconstruction (vs. Billroth Ⅰ, OR 2.707, P = 0.002) were significant risk factors for ASIC. In the multivariable analysis, male sex (OR 2.364, P = 0.028) and R-Y reconstruction (vs. Billroth Ⅰ, OR 2.310, P = 0.015) were independent risk factors for ASIC.

CONCLUSIONS

Male sex and R-Y reconstruction were risk factors for ASIC after distal gastrectomy. Therefore, when performing surgery on male patients or when R-Y reconstruction is selected after gastrectomy for gastric cancer, surgeons should pay special attention to prevent ASIC.

The association between skeletal muscle mass index (SMI) and survival after gastrectomy: A systematic review and meta-analysis of cohort studies

OBJECTIVE

Low skeletal muscle mass index (SMI) is frequently identified in gastric cancer patients but its association with patient survival rate is not clear. This systematic review and meta-analysis aimed to clarify the association between SMI and overall survival in gastric cancer patients after gastrectomy.

METHODS

PubMed, Scopus, and Web of Science were searched from database inception until July 2021. Studies were eligible if they included gastric cancer patients, measured the SMI level, reported SMI before gastrectomy, defined sarcopenia according to SMI, and had a cohort or case-control design. Primary outcome was cancer survival rate. The risk of bias of individual studies was assessed using the Newcastle - Ottawa Scale.

RESULTS

Overall, 22 cohort studies including 7,203 participants were included. The quality of the included studies was moderate to high. A higher overall survival rate was associated with a higher SMI (RR = 1.62, 95% CI: 1.42-1.85). Subgroup analysis suggested a stronger association in overweight or obese patients (RR = 2.39, 95% CI: 1.13-5.09; I2 = 77%; heterogeneity P < 0.01). But no significant differences in the association based on the surgery type (curative surgery vs radical surgery) or the type of gastrectomy (total gastrectomy vs sub-total gastrectomy) were observed.

CONCLUSIONS

It is suggested that SMI can be a prognostic indicator for overall survival in gastric cancer patients, especially in overweight and obese patients.

Impact of BMI on the Survival of Renal Cell Carcinoma Patients Treated with Targeted Therapy: A Systematic Review and Meta-Analysis

It is unclear whether obese renal cell carcinoma (RCC) patients treated with targeted therapy have better survival. We conducted this meta-analysis to assess the prognostic significance of body mass index (BMI) in RCC patients treated with targeted therapy. We systematically searched PubMed, Embase, Cochrane Library, and Web of Science by November 17, 2021. We calculated effect outcomes using random-effects and fixed-effects models. Fifteen articles were identified. We found that RCC patients treated with targeted therapy with BMI over 25 obtained better overall survival (OS) (hazard ratio [HR] = 0.69, 95% confidence interval [CI] = 0.58-0.82, I2 = 75.5%, p < 0.001) and progression-free survival (PFS) (HR = 0.71, 95%CI = 0.55-0.92, I2 = 69.7%, p = 0.006) than patients with BMI below 25. Obese (BMI over 30) patients had remarkably better OS (HR = 0.77, 95%CI = 0.70-0.85, I2 = 0.0%, p = 0.439) and PFS (HR = 0.86, 95%CI = 0.77-0.97, I2 = 0.0%, p = 0.934) than patients with BMI below 25. Overweight (BMI over 25 but below 30) patients also had better OS (HR = 0.86, 95%CI = 0.79-0.93, I2 = 17.7%, p = 0.295) and PFS (HR = 0.82, 95%CI = 0.74-0.90, I2 = 0.0%, p = 0.904) than patients with BMI below 25. When using BMI as continuous variable, patients with high BMI also obtained significantly better OS (HR = 0.92, 95%CI = 0.88-0.96, I2 = 0.0%, p = 0.806). Therefore, higher BMI was associated with greater OS and PFS in RCC patients treated with targeted therapy.

Prognostic role of pretreatment skeletal muscle index in gastric cancer patients: A meta-analysis

Background: The association between pretreatment skeletal muscle index (SMI) and long-term survival of gastric cancer patients remains unclear up to now. The aim of this meta-analysis was to identify the prognostic value of pretreatment SMI in gastric cancer. Methods: The PubMed, EMBASE and Web of Science electronic databases were searched up to 5 June 2022 for relevant studies. The primary outcome was overall survival (OS) and the second outcomes were disease-free survival (DFS) and cancer-specific survival (CSS). The hazard ratios (HRs) and 95% confidence intervals (CIs) were combined to assess the relationship between pretreatment SMI and survival of gastric cancer patients. All statistical analyses were conducted by STATA 15.0 software. Results: A total of 31 retrospective studies involving 12,434 patients were enrolled in this meta-analysis. The pooled results demonstrated that lower pretreatment was significantly associated with poorer OS (HR = 1.53, p < 0.001). Besides, lower pretreatment SMI was also related with worse DFS (HR = 1.39, p < 0.001) and CSS (HR = 1.96, p < 0.001). Conclusion: Pretreatment SMI was significantly associated with prognosis of gastric cancer patients and lower SMI predicted worse survival. However, more prospective high-quality studies are still needed to verify our findings.

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.

Preoperative computed tomography-determined sarcopenia is a reliable prognostic factor in patients with gastric cancer after radical gastrectomy: A sex-specific analysis

Background

The predictive role of sarcopenia in cancer prognosis is an area of increasing concern. However, the influence of sex difference on the predictive role of sarcopenia in cancer prognosis has not been clearly defined. This retrospective cohort study investigated the effect of preoperative sarcopenia on the long-term outcomes of patients with gastric cancer (GC) based on sexual dimorphism.

Methods

Preoperative abdominal computed tomography (CT) scans from 379 GC patients who underwent radical gastrectomy were carefully analyzed. The patients were categorized into sarcopenia and non-sarcopenia groups according to the L3 skeletal muscle index (L3 SMI) measured on CT scans. Moreover, other indexes which can be used to evaluate the muscle area or the muscle quality, including skeletal muscle area (SMA), visceral fat area (VFA), subcutaneous fat area (SFA), skeletal muscle radiation attenuation (SM-RA), visceral fat index (VFI), subcutaneous fat index (SFI), and subcutaneous and visceral ratio (SV), were obtained from CT scans.

Results

There were 254 men and 125 women included in our study. After calculation, we defined sex-specific SMI-related mortality cutoff as 39.73 and 32.97 cm²/m² for men and women. Univariable analysis showed that pathological tumor-node-metastasis (pTNM), depth of invasion, lymph node metastasis, differentiation degree, preoperative sarcopenia (for men), SMA (for men), L3 SMI, SFA (for women), SFI (for women), SV (for women), and SM-RA (especially for men) were significant independent predictors of overall survival (OS). Multivariable analysis showed that pTNM, depth of invasion, poor differentiation, and SM-RA were significantly associated with 5-year OS in GC patients. However, CT-determined sarcopenia was associated with significantly worse OS only in men, and SFA was significantly associated with 5-year OS only in women.

Conclusion

SM-RA is a reliable prognostic factor in patients with GC after radical gastrectomy. The impact of indexes mentioned above on survival outcomes is dependent on sex. CT-determined preoperative sarcopenia, a muscle-related indicator, was associated with outcomes in men. Adipose-related indicator (SFA), instead, was associated with outcomes in women.

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.