Impact of intra-abdominal fat on surgical outcome and overall survival of patients with gastric cancer

Assessment of Laparoscopic Indocyanine Green Tracer-guided Lymphadenectomy After Neoadjuvant Chemotherapy for Locally Advanced Gastric Cancer: A Randomized Controlled Trial

OBJECTIVE

To assess the effectiveness of indocyanine green (ICG)-guided lymph node (LN) dissection during laparoscopic radical gastrectomy after neoadjuvant chemotherapy (NAC) in patients with locally advanced gastric cancer (LAGC).

BACKGROUND

Studies on ICG imaging use in patients with LAGC on NAC are rare.

METHODS

Patients with gastric adenocarcinoma (clinical T2-4NanyM0) who received NAC were randomly assigned to receive ICG-guided laparoscopic radical gastrectomy or laparoscopic radical gastrectomy alone. Here, we reported the secondary endpoints including the quality of lymphadenectomy (total retrieved LNs and LN noncompliance) and surgical outcomes.

RESULTS

Overall, 240 patients were randomized. Of whom, 236 patients were included in the primary analysis (118 in the ICG group and 118 in the non-ICG group). In the ICG group, the mean number of LNs retrieved was significantly higher than in the non-ICG group within the D2 dissection (48.2 vs 38.3, P < 0.001). The ICG fluorescence guidance significantly decreased the LN noncompliance rates (33.9% vs 55.1%, P = 0.001). In 165 patients without baseline measurable LNs, ICG significantly increased the number of retrieved LNs and decreased the LN noncompliance rate ( P < 0.05). For 71 patients with baseline measurable LNs, the quality of lymphadenectomy significantly improved in those who had a complete response ( P < 0.05) but not in those who did not ( P > 0.05). Surgical outcomes were comparable between the groups ( P > 0.05).

CONCLUSIONS

ICG can effectively improve the quality of lymphadenectomy in patients with LAGC who underwent laparoscopic radical gastrectomy after NAC.

Association of preoperative muscle-adipose index measured by computed tomography with survival in patients with esophageal squamous cell carcinoma

BACKGROUND

Conventional nutritional metrics are closely associated with the prognosis of patients with radically resected esophageal squamous cell carcinoma (ESCC). Nevertheless, the prognostic implications of muscle and adipose tissue composite indexes in ESCC remain unknown.

METHODS

We retrospectively analyzed clinicopathological data of 304 patients who underwent resected ESCC. To obtain measurements of the muscle and adipose indexes, preoperative computed tomography (CT) images were used to quantify skeletal-muscle adipose tissue. The diagnostic threshold for muscle-adipose imbalance was determined using X-tile software and used to analyze the association between the muscle-adipose index (MAI) and survival. Instantaneous risk of recurrence was assessed using a hazard function. We constructed a nomogram based on the MAI and other clinical characteristics and established a novel predictive model with independent prognostic factors. The prognostic capabilities of these nomograms were evaluated using calibration curves, receiver operating characteristic (ROC) curves, and decision-curve analysis (DCA).

RESULTS

The overall survival (OS) and disease-free survival (DFS) rates in the muscle-adipose-balanced group were significantly better than those in the muscle-adipose-imbalanced group. Multivariate analyses revealed that the MAI, prognostic nutritional index (PNI), tumor stage, and tumor differentiation were independent prognostic factors for OS and DFS in patients with resected ESCC (P < 0.05). The nuclear density curve indicated a lower risk of recurrence for patients in the muscle-adipose-balanced group than that for their imbalanced counterparts. Conversely, the nuclear density curve for PNI was confounded. Postoperative radiotherapy- (RT) benefit analysis demonstrated that patients with ESCC in the muscle-adipose-balanced group could benefit from adjuvant RT.

CONCLUSION

This study confirmed that preoperative MAI could serve as a useful independent prognostic factor in patients with resected ESCC. A nomogram based on the MAI and other clinical characteristics could provide individualized survival prediction for patients receiving radical resection. Timely and appropriate nutritional supplements may improve treatment efficacy.

Laparoscopic D2+ lymph node dissection in patients with obesity and gastric cancer: A retrospective study

D2 lymph node dissection is widely used in laparoscopic radical gastrectomy for gastric cancer, and its efficacy and safety are known for patients with obesity. Currently, D2+ lymph node dissection is also applied to certain patients with gastric cancer of later stages. Due to the high difficulty of D2+ surgery, it is more challenging to perform on patients with obesity. There is currently limited research on the efficacy and safety of D2+ surgery in obese patients with gastric cancer. The present study aimed to retrospectively analyze the clinical data of patients undergoing laparoscopic radical gastrectomy for gastric cancer admitted to a single gastroenterology department. Patients with a body mass index ≥25 kg/m2 were included in the study. A total of 149 patients were selected as the research subjects and divided into two groups. The observation group comprised 74 patients who underwent D2+ lymph node dissection, while the control group comprised 75 patients who underwent standard D2 lymph node dissection. The surgical performance, postoperative recovery and postoperative complications of the two groups were compared. The results showed that the rates of conversion to open surgery in the D2+ and D2 groups were 5.4% (4/74) and 2.7% (2/75), respectively, and were not significantly different. The duration of surgery in the D2+ group (282.55±23.02 min) was significantly longer than that in the D2 group (271.45±20.05 min). The mean number of lymph node dissections in the D2+ group was 28.57±7.19, which was significantly higher than that in the D2 group (25.29±6.41). No statistically significant differences in intraoperative blood loss, time to first flatus, postoperative hospitalization days, total hospitalization expenses or postoperative complications was detected between the two groups. There were no deaths in either group within the 30-day perioperative period. In addition, there was no significant difference in the 3-year overall survival rate between the two groups, while the 5-year overall survival rate of the D2+ group was significantly higher than that of the D2 group. For obese patients with gastric cancer, D2+ surgery may increase the duration of surgery and slightly increase intraoperative blood loss compared with standard D2 radical surgery, but does not increase the incidence of postoperative complications. Moreover, D2+ surgery increases the number of lymph node dissections and improves the 5-year survival rate of patients. Therefore, it may be concluded that laparoscopic D2+ lymph node dissection is safe and feasible for obese patients with 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.

Detection of sarcopenic obesity and prediction of long-term survival in patients with gastric cancer using preoperative computed tomography and machine learning

Background

Previous studies evaluating the prognostic value of computed tomography (CT)‐derived body composition data have included few patients. Thus, we assessed the prevalence and prognostic value of sarcopenic obesity in a large population of gastric cancer patients using preoperative CT, as nutritional status is a predictor of long‐term survival after gastric cancer surgery.

Methods

Preoperative CT images were analyzed for 840 gastric cancer patients who underwent gastrectomy between March 2009 and June 2018. Machine learning algorithms were used to automatically detect the third lumbar (L3) vertebral level and segment the body composition. Visceral fat area and skeletal muscle index at L3 were determined and used to classify patients into obesity, sarcopenia, or sarcopenic obesity groups.

Results

Out of 840 patients (mean age = 60.4 years; 526 [62.6%] men), 534 (63.5%) had visceral obesity, 119 (14.2%) had sarcopenia, and 48 (5.7%) patients had sarcopenic obesity. Patients with sarcopenic obesity had a poorer prognosis than those without sarcopenia (hazard ratio [HR] = 3.325; 95% confidence interval [CI] = 1.698–6.508). Multivariate analysis identified sarcopenic obesity as an independent risk factor for increased mortality (HR = 2.608; 95% CI = 1.313–5.179). Other risk factors were greater extent of gastrectomy (HR = 1.928; 95% CI = 1.260–2.950), lower prognostic nutritional index (HR = 0.934; 95% CI = 0.901–0.969), higher neutrophil count (HR = 1.101; 95% CI = 1.031–1.176), lymph node metastasis (HR = 6.291; 95% CI = 3.498–11.314), and R1/2 resection (HR = 4.817; 95% CI = 1.518–9.179).

Conclusion

Body composition analysis automated by machine learning predicted long‐term survival in patients with gastric cancer.

Impact of obesity on the outcomes after gastrectomy for gastric cancer: A meta-analysis

The impact of body mass index (BMI) on surgical outcomes has previously been studied in relation to several oncological procedures. Regarding gastric cancer surgery, published results have been contradicting in terms of degree of technical difficulty, risk of postoperative complications and survival. In an attempt to clarify these issues, we performed a meta-analysis to evaluate the impact of obesity (defined as BMI ≥ 30 kg/m²) on outcomes after gastrectomy for gastric cancer. The meta-analysis was performed according to the PRISMA guidelines. Eligible studies were identified through search of PubMed, EMBASE, Web of Science and Cochrane Library databases. Quality assessment was performed using the Newcastle-Ottawa scale. The meta-analysis was conducted using random-effects modeling. A total of 11 studies with 13 538 patients were eligible for analysis. Obesity was associated with a significantly longer operation time (WMD = 19.38 min, 95% CI 12.72-26.04; p < 0.001), increased risk of overall complications (RR = 1.23, 95% CI 1.06-1.42; p = 0.005) and pulmonary complications (RR = 3.81, 95% CI 2.24-6.46; p < 0.001). These findings remained irrespective type of surgery (laparoscopic vs. open) and type of gastrectomy. No differences were found regarding blood loss, number of resected lymph nodes, anastomotic leakage, hospital stay, 30-day mortality and 5-year overall survival. The conclusion of the current meta-analysis is that high BMI in gastric cancer patients is associated with longer operative time and more frequent overall postoperative complications. However, it has no negative impact on survival, indicating that gastrectomy is a safe procedure for this group of 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.

Prognostic implications of visceral obesity on gastric adenocarcinoma: does it really matter?

PURPOSE

To evaluate the association of visceral adiposity measured on computed tomography (CT) in preoperative period with lymph node (LN) metastasis and overall survival in gastric adenocarcinoma patients.

METHODS

Preoperative CT scans of 246 gastric adenocarcinoma patients who did not receive neoadjuvant chemoradiotherapy were evaluated. Visceral fat area (VFA), subcutaneous fat area (SFA) and Total fat area (TFA), VFA/TFA ratio were quantified by CT. VFA/TFA > 29% was defined as visceral obesity. The differentiation, t-stage, n-stage and the number of harvested-metastatic LNs were noted. The maximum thickness of tumor and localization were recorded from CT. Chi-square, Student's t-test, multiple Cox regression, Spearman's correlation coefficient, and Kaplan-Meier algorithm were performed.

RESULTS

The overall survival (OS) rates and N-stage were not different significantly between viscerally obese and non-obese group (p = 0.994, p = 0.325). The number of metastatic LNs were weakly inversely correlated with VFA (r = -0.144, p = 0.024). Univariate analysis revealed no significant association between visceral obesity and OS or LN metastasis (p = 0.377, p = 0.736). In multivariate analyses, OS was significantly associated with poorly differentiation (HR = 1.72, 95% CI =1.04-2.84, p = 0.035), higher pathologic T and N stage (T4 vs T1 + T2 HR = 2.67, 95% CI =1.18-6.04, p = 0.019; T3 vs T1 + T2 HR = 1.98, 95% CI = 0.90-4.33, p = 0.089; N3b vs N0 HR = 2.97, 95% CI1.45-6.0, p = 0.003; N3 (3a+ 3b) vs N0 HR = 2.24 95% CI =1.15-4.36, p = 0.018).

CONCLUSION

Visceral obesity may not be a prognostic factor in resectable gastric adenocarcinoma patients.

Low body mass index is an independent predictor of poor long-term prognosis among patients with resectable gastric cancer

BACKGROUND

The association between body mass index (BMI) and clinical outcomes remains unclear among patients with resectable gastric cancer.

AIM

To investigate the relationship between BMI and long-term survival of gastric cancer patients.

METHODS

This retrospective study included 2526 patients who underwent radical gastrectomy for gastric cancer between September 2013 and June 2018. The patients were divided into four groups: Group A (low BMI, < 18.5 kg/m²), group B (normal BMI, 18.5-24.9 kg/m²), group C (overweight, 25-29.9 kg/m²), and group D (obese, ≥ 30 kg/m²). Clinicopathological findings and survival outcomes were recorded and analyzed.

RESULTS

Preoperative weight loss was more common in the low-BMI group, while diabetes was more common in the obese group. Upper-third gastric cancer accounted for a large proportion of cases in the higher BMI groups. Major perioperative complications tended to increase with BMI. The 5-year overall survival rates were 66.4% for group A, 75.0% for group B, 77.1% for group C, and 78.6% for group D. The 5-year overall survival rate was significantly lower in group A than in group C (P = 0.008) or group D (P = 0.031). Relative to a normal BMI value, a BMI of < 18.5 kg/m² was associated with poor survival (hazard ratio: 1.558, 95% confidence interval: 1.125-2.158, P = 0.008).

CONCLUSION

Low BMI, but not high BMI, independently predicted poor survival in patients with resectable gastric cancer.

Three different computed tomography obesity indices, two standard methods, and one novel measurement, and their association with outcomes after colorectal cancer surgery

BACKGROUND

Obesity can be measured by different indices, either as body mass index (BMI) or by more intuitive radiological measurements, and obesity has been shown to have an impact on outcome after colorectal cancer (CRC) surgery.

PURPOSE

To investigate whether the thickness of the subcutaneous adipose tissue (SAT) in the abdominal wall can be used as a surrogate for the visceral fat area (VFA)-both measured on computed tomography (CT)-in prediction of short- and long-term outcomes after elective CRC surgery.

MATERIAL AND METHODS

Preoperative CT scans of all patients having elective CRC surgery (stages I-III), in two consecutive years at a single-center institution, were used to measure the SAT (mm) and VFA (cm²). BMI was calculated for each patient. The three different obesity indices were used in different analyses in order to predict postoperative complications and overall survival.

RESULTS

A BMI >30 kg/m² was an independent prognostic factor in postoperative complications (odds ratio 3.2, 95% confidence interval [CI] 1.43-7.03). SAT and VFA were not able to predict complications. Patients considered visceral obese according to a high VFA (>130 cm²) had poorer survival (hazard ratio 1.53, 95% CI 1.00-2.36) compared to non-obese patients, but in the adjusted model, VFA lost its predictive power. BMI and SAT were not able to predict mortality.

CONCLUSION

The novel measurement of the thickness of SAT in a preoperative setting before elective CRC surgery cannot predict either postoperative complications or overall survival; the other obesity indices had better predictive features.

Body mass index and skeletal muscle index are useful prognostic factors for overall survival after gastrectomy for gastric cancer: Retrospective cohort study

Among patients undergoing gastrectomy for gastric cancer, the impact of anthropometric indices on surgical outcomes is not well-established. The aim of this study was to evaluate the prognostic significance of the skeletal muscle index (SMI) and body mass index (BMI) on overall survival (OS) in patients with gastric cancer.A total of 305 patients who underwent curative gastrectomy for gastric adenocarcinoma between January 2005 and March 2008 were enrolled. Patients were classified into groups based on the SMI and BMI. The SMI was measured by preoperative abdominal computed tomography (CT). The SMI groups were classified based on gender-specific cut-off values obtained by means of optimum stratification. BMI groups were divided according to the World Health Organization definition of obesity for Asians.The mean SMI was 58.2 cm/m and the mean BMI was 23.2 kg/m. One hundred fifteen (37.7%) patients had sarcopenia based on the diagnostic cut-off values (56.2 cm/m for men and 53.6 cm/m for women). Apart from gender, there were no significant differences in patient characteristics or surgical outcomes between the SMI groups. In the underweight group, tumor (T) stage, tumor-node-metastasis (TNM) stage, number of retrieved lymph nodes, D2 dissection, and hospital stay were significantly increased compared with the overweight/obese group. High and low BMI, and low SMI, were independent prognostic factors for OS (hazard ratio [HR] = 2.355, 1.736, and 1.607, respectively; P = .009, .023, and .033, respectively).SMI and BMI did not impact perioperative morbidity in patients undergoing gastrectomy for gastric cancer. Both SMI and BMI are useful prognostic factors for OS in gastric cancer patients after gastrectomy.

Clinical Outcomes of Laparoscopic Versus Laparotomic Distal Gastrectomy in Gastric Cancer Patients: A Multilevel Analysis Based on a Nationwide Administrative Database in Japan

BACKGROUND

The present study compared the short-term outcomes and costs of laparoscopic distal gastrectomy (LDG) with those of open distal gastrectomy (ODG) for gastric cancer using a nationwide administrative database in Japan.

METHOD

Overall, 37,752 patients with gastric cancer who underwent distal gastrectomy at 1074 hospitals in the fiscal year 2012-2013 were evaluated using a diagnosis procedure combination database in Japan. We performed a retrospective analysis via a multilevel analysis (MLA) of the short-term surgical results and costs of the LDG and ODG groups. The models included the age, sex, comorbid complications, smoking, body mass index (BMI), activity of daily living (ADL), stage, and the number of cases of gastrectomy per facility for adjustment. The in-hospital mortality relative to the hospital volume was also compared.

RESULTS

The LDG group required postoperative blood transfusion less frequently and had fewer postoperative complications, shorter hospitalization, and lower operative mortality than the ODG group. While this stage did not correlate with the in-hospital mortality, the surgical method, age, sex, ADL, BMI, comorbidity, and yearly volume showed a correlation. A significant association in the in-hospital mortality was observed between low- and very-high-volume hospitals.

CONCLUSION

In this large nationwide cohort of patients with gastric cancer using an MLA, LDG was shown to be safer with lower mortality and postoperative complication rates than ODG.

Visceral Fat Area (VFA) Superior to BMI for Predicting Postoperative Complications After Radical Gastrectomy: a Prospective Cohort Study

BACKGROUND

Obesity may impact surgical outcomes of gastrectomy. Whether visceral fat area (VFA) is a better obesity parameter than body mass index (BMI) is still controversial. The aim of this study is to compare the accuracy and effectiveness of VFA and BMI in predicting the short-term surgical outcomes of gastrectomy.

METHODS

Patients who were diagnosed with gastric cancer were measured for BMI and VFA preoperatively and then divided into a VFA-H (VFA-high) group and VFA-L (VFA-low) group, at the cutoff point of 100 cm², and a BMI-H (BMI-high) group and BMI-L (BMI-low) group, at the cutoff point of 25 kg/m². The short-term surgical outcomes were compared between the different groups.

RESULTS

In total, 276 patients were enrolled in this study; 55 (19.9%) patients were classified into the BMI-H group, and 122 (44.2%) patients were classified into the VFA-H group. There was a significant correlation between BMI and VFA (r = 0.652, p < 0.001). Compared with the VFA-L group, the VFA-H group had a higher incidence of postoperative complications (31.1% vs. 13.0%; p < 0.001), longer operation duration (270.0 (235.0-305.0) vs. 255.0 (223.8-295.0), p = 0.046), and more blood loss (100.0 (100.0-150.0) vs. 80.0 (80.0-100.0), p < 0.001), while the BMI-H group had more blood loss than the BMI-L group (100.0 (100.0-120.0) vs. 100.0(80.0-100.0), p = 0.006). Logistic regression showed that VFA was an independent risk factor for postoperative complications (odds ratio 2.813, 95% CI 1.523-5.194; p = 0.001).

CONCLUSION

For gastric cancer patients, VFA is superior to BMI in accurately and effectively illuminating the impact of obesity on short-term surgical outcomes.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT02800005.

Preoperative weight loss program involving a 20-day very low-calorie diet for obesity before laparoscopic gastrectomy for gastric cancer

INTRODUCTION

The increased visceral fat in patients with obesity can increase the technical difficulty of surgery. This study was performed to evaluate a preoperative 20-day very low-calorie diet for obesity before laparoscopic gastrectomy for gastric cancer.

METHODS

This prospective single-center study involved patients with obesity who were planning to undergo laparoscopic gastrectomy for gastric cancer. Obesity was defined according to the Japanese criteria: BMI ≥25 kg/m² or waist circumference ≥85 cm in men and ≥90 cm in women. The patients underwent a preoperative 20-day very low-calorie diet and received nutritional counseling. Weight loss, body composition, visceral fat mass, and operative outcomes were evaluated.

RESULTS

Thirty-three patients were enrolled from September 2013 to August 2015. Their median age was 71 years, and 78.8% were men. Their median bodyweight and BMI were 72.3 kg (range, 53.8-82.5 kg) and 26.0 kg/m² (range, 23.5-31.0 kg/m² ), respectively. The patients achieved a mean weight loss of 4.5% (95% confidence interval [CI]: 3.8-5.1), corresponding to 3.2 kg (95%CI: 2.7-3.7 kg). Body fat mass was significantly decreased by a mean of 2.5 kg (95%CI: 1.9-3.1), whereas skeletal muscle mass was unaffected (mean: -0.20 kg [95%CI: -0.55-0.15]). The visceral fat mass reduction rate was high as 16.8% (range, 11.6%-22.0%). All patients underwent laparoscopic gastrectomy as planned. Severe postoperative morbidity (Clavien-Dindo grade ≥III) was seen in only one patient (3.0%).

CONCLUSION

The preoperative 20-day very low-calorie diet weight loss program is promising for the treatment of obesity before laparoscopic gastrectomy for gastric cancer.

Body composition assessment and sarcopenia in patients with gastric cancer: a systematic review and meta-analysis

INTRODUCTION

There has recently been increased interest in the assessment of body composition in patients with gastric cancer for the purpose of prognostication. This systematic review and meta-analysis aim to evaluate the current literature on body composition assessment in patients with gastric cancer and its impact on peri-operative outcomes.

METHODS

A systematic literature search was conducted for studies reporting assessment of body composition in patients with gastric cancers. Meta-analysis of postoperative outcomes (overall and major complications, anastomotic leaks, pulmonary complications) and survival was performed using random effects models.

RESULTS

Thirty-nine studies reported the assessment of body composition in 8402 patients. Methods used to assess body composition in patients with gastric cancers were computerized tomography (n = 26), bioelectrical impedance analysis (n = 9), and dual-energy-X-ray-absorptiometry (n = 3). Only 21 studies reported the impact of pre-operative sarcopenia on post-operative outcomes. Sarcopenic patients have significantly higher rates of postoperative major complications (n = 12, OR 1.67, CI_95% 1.14-2.46, p = 0.009), and pulmonary (n = 8, OR 4.01, CI_95% 2.23-7.21, p < 0.001) complications after gastrectomy. Meta-analysis of nine studies reporting overall survival after gastrectomy identified significantly worse survival in patients with pre-operative sarcopenia (HR 2.12, CI_95% 1.89-2.38, p < 0.001).

CONCLUSIONS

Assessment of body composition has the potential to become a clinically useful tool that could support decision-making in patients with gastric cancer. However, variation in methods of assessing and reporting body composition in this patient group limits assessment of current post-operative outcomes.

Impact of intra-peritoneal fat distribution on intra-operative bleeding volume with D2 lymphadenectomy in Chinese patients with gastric cancer

OBJECTIVE

To explore the quantitative measurements and evaluation of intra-peritoneal fat distribution by MDCT and its significance in predicting intra-operative bleeding volume during D2 lymphadenectomy in gastric cancer (GC) patients.

METHODS

From June 2016 to September 2017, GC patients scheduled for open gastrectomy with D2 lymph-node dissection were enrolled. According to the BMI, the subjects were then classified as normal BMI(BMI<25 kg/m²); overweight (BMI = 25-30 kg/m²) and obese (BMI≥30 kg/m²). According to the intraoperative blood loss (IBL), the patients were further separated into high IBL (IBL; ≥ 300 ml) or low IBL (<300 ml). Clinicopathological parameters between the groups were statistically compared and univariate and multivariate analysis were used to identify predictive factors such as intra-peritoneal fat areas (IFA) and intra-peritoneal fat areas ratio (IFAR) for high IBL.

RESULTS

A total of 226 patients were included in the study where 53 patients underwent distal while 173 underwent total gastrectomy. According to the BMI classification, there were 25 normal BMI, 108 overweight and 25 obese subjects. According to the IBL, there were 98 high IBL and 128 low IBL subjects. IFA and IFAR were significantly greater in the high IBL group than in the low IBL group. There was no significant difference in any other clinicopathological factors between the high IBL group and the low IBL group. Multivariate analysis revealed that high IFA and IFAR independently predicted high IBL.

CONCLUSION

The use of MDCT to evaluate the precise distribution of abdominal fat during preoperative examination can prompt surgeons to develop techniques to decrease intraoperative bleeding in obese patients. Nevertheless, it is yet necessary to be surgically more meticulous when dealing with patients with high IFA or high IFA/IFAR in order to improve the outcome of D2 gastrectomy.

Does high body mass index negatively affect the surgical outcome and long-term survival of gastric cancer patients who underwent gastrectomy: A systematic review and meta-analysis

BACKGROUND

Whether high body mass index (BMI) was associated with increased postoperative complications and unfavorable prognosis of gastric cancer (GC) patients remain controversial. In the present study, we performed a systematic review and meta-analysis to evaluate the impact of high BMI on surgical outcome, postoperative complications and long-term survival of GC patients.

METHODS

The related studies were identified by searching PubMed and Embase databases. According to the BMI, all GC patients were classified into BMI ≥25 kg/m² group and BMI <25 kg/m² group. The relevant data was extracted and pooled effect size was assessed using a fixed effect model or random effect model.

RESULTS

A total of 36 relevant studies involving 30,642 GC patients were included in this meta-analysis. The results indicated that high BMI patients had longer operation time, fewer number of retrieved lymph nodes and larger amount of intraoperative blood loss than other patients, regardless of open gastrectomy or laparoscopic gastrectomy. In addition, the risk of postoperative complications was significantly higher in the patients with BMI ≥25 kg/m² than in those with BMI <25 kg/m², especially for infectious complications. However, high BMI had no negative impact on postoperative mortality and long-term survival of GC patients.

CONCLUSION

Despite the increased surgical difficulty and postoperative complications, high BMI was not associated with the prognosis of GC patients. To reduce the risk of postoperative complications, more meticulous operation technique and improved perioperative management should be necessary for high BMI patients.

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.

Long-term Outcomes of Laparoscopic Versus Open Surgery for Clinical Stage I Gastric Cancer: The LOC-1 Study

Background:

Clinical trials comparing laparoscopic gastrectomy (LG) versus traditional open gastrectomy (OG) have been planned, their surgical outcomes reported but their oncologic outcomes are still pending. Consequently, we have conducted this large-scale historical cohort study to provide relevant information rapidly to guide our current practice.

Methods:

Through a consensus meeting involving surgeons, biostatisticians, and epidemiologists, 30 variables of preoperative information possibly influencing surgeons’ choice between LG versus OG and potentially associating with outcomes were identified to enable rigorous estimation of propensity scores. A total of 4235 consecutive patients who underwent gastrectomy for gastric adenocarcinoma were identified and their relevant data were gathered from the participating hospitals. After propensity score matching, 1848 patients (924 each for LG and OG) were selected for comparison of long-term outcomes.

Results:

In the propensity-matched population, the 5-year overall survival was 96.3% [95% confidence interval (CI) 95.0–97.6] in the OG as compared with 97.1% (95% CI, 95.9–98.3) in LG. The number of all-cause death was 33/924 in the OG and 24/924 in the LG through the entire period, and the hazard ratio (LG/OG) for overall death was 0.75 (95% CI, 0.44–1.27; P = 0.290). The 3-year recurrence-free survival was 97.4% (95% CI, 96.4–98.5) in the OG and 97.7% (95% CI, 96.5–98.8) in the LG. The number of recurrence was 22/924 in the OG and 21/924 in the LG through the entire period, and the hazard ratio was 1.01 (95% CI, 0.55–1.84; P = 0.981).

Conclusions:

This observational study adjusted for all-known confounding factors seems to provide strong enough evidence to suggest that LG is oncologically comparable to OG for gastric cancer.

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.

Is There any Role of Visceral Fat Area for Predicting Difficulty of Laparoscopic Gastrectomy for Gastric Cancer?

PURPOSE

Obesity is associated with morbidity following gastric cancer surgery, but whether obesity influences morbidity after laparoscopic gastrectomy (LG) remains controversial. The present study evaluated whether body mass index (BMI) and visceral fat area (VFA) predict postoperative complications.

MATERIALS AND METHODS

A total of 217 consecutive patients who had undergone LG for gastric cancer between May 2003 and December 2005 were included in the present study. We divided the patients into two groups ('before learning curve' and 'after learning curve') based on the learning curve effect of the surgeon. Each of these groups was sub-classified according to BMI (<25 kg/m(2) and ≥25 kg/m(2)) and VFA (<100 cm(2) and ≥100 cm(2)). Surgical outcomes, including operative time, quantity of blood loss, and postoperative complications, were compared between BMI and VFA subgroups.

RESULTS

The mean operative time, length of hospital stay, and complication rate were significantly higher in the before learning curve group than in the after learning curve group. In the subgroup analysis, complication rate and length of hospital stay did not differ according to BMI or VFA; however, for the before learning curve group, mean operative time and blood loss were significantly higher in the high VFA subgroup than in the low VFA subgroup (P=0.047 and P=0.028, respectively).

CONCLUSIONS

VFA may be a better predictive marker than BMI for selecting candidates for LG, which may help to get a better surgical outcome for inexperienced surgeons.

Sarcopenia is highly prevalent in patients undergoing surgery for gastric cancer but not associated with worse outcomes

OBJECTIVES

Aim of this study was to assess the prevalence of sarcopenia and body composition (i.e., subcutaneous and visceral fat) in gastric cancer surgical patients and its association with adverse postoperative outcome.

METHODS

Preoperative CT scans were obtained from all patients who underwent surgery for gastric adenocarcinoma between January 2005 and September 2012. Total muscle and adipose tissue cross-sectional area were measured at the level of the third lumbar vertebra (L3) transverse processes. Sarcopenia was defined according to gender- and body mass index (BMI)-specific cutoff points. Primary outcome was in-hospital mortality. Secondary outcomes were severe postoperative complications (i.e., Clavien-Dindo classification ≥3a complications) and 6-month mortality.

RESULTS

In 152 out of a total of 180 (84.4%) patients, a CT-scan was available for analysis. In total, 86 (57.7%) of the patients were classified as sarcopenic. Sarcopenia was no predictor for in-hospital mortality (P = 0.52), severe complications (P = 1.00) or 6-month mortality (P = 0.69). Intraabdominal and subcutaneous adipose tissue measurements were not associated with in-hospital mortality, severe complications or 6-month mortality.

CONCLUSIONS

In this population of gastric cancer surgical patients, the prevalence of sarcopenia was 57.7%, which is high compared to other abdominal surgical oncology populations. However, sarcopenia was not associated with postoperative morbidity or mortality.

Clinical and Oncological Value of Preoperative BMI in Gastric Cancer Patients: A Single Center Experience

Introduction. The impact of preoperative BMI on surgical outcomes and long-term survival of gastric cancer patients was investigated in various reports with contrasting results. Materials & Methods. A total of 378 patients who underwent a surgical resection for primary gastric cancer between 1994 and 2011 were retrospectively studied. Patients were stratified according to BMI into a normal group (<25, group A), an overweight group (25-30, group B), and an obesity group (≥30, group C). These 3 groups were compared according to clinical-pathological characteristics, surgical treatment, and long-term survival. Results. No significant correlations between BMI and TNM (2010), UICC stage (2010), Lauren's histological type, surgical results, lymph node dissection, and postoperative morbidity and mortality were observed. Factors related to higher BMI were male gender (P < 0.05), diabetes (P < 0.001), and serum blood proteins (P < 0.01). A trend to fewer lymph nodes retrieved during gastrectomy with lymphadenectomy in overweight patients (B and C groups) was observed, although not statistically significant. There was no difference in overall survival or disease-specific survival between the three groups. Conclusion. According to our data, BMI should not be considered a significant predictor of postoperative complications or long-term result in gastric cancer patients.