Abstract
Objective
We aimed to investigate the relationship between the visceral to subcutaneous fat area ratio (V/S ratio) and incidence of early postoperative small bowel obstruction (EPSBO) following total gastrectomy for cardia cancer.
Methods
We conducted a retrospective analysis among patients with cardia cancer who underwent elective total gastrectomy with esophagojejunostomy Roux-en-Y anastomosis at Nanjing Yimin Hospital between November 2019 and April 2024. Preoperative, intraoperative, and postoperative factors were meticulously monitored. The V/S ratio was calculated using computed tomography scans at the umbilical level with Slice-O-Matic software (Tomovision, Montreal, Canada). Statistical analyses included logistic regression and receiver operating characteristic (ROC) curve analysis.
Results
Among 175 patients, 27 (15.4%) developed EPSBO. The V/S ratio was significantly higher in the EPSBO group (1.76 ± 1.05 vs. 1.01 ± 0.54). Logistic regression identified the V/S ratio as a significant predictor of EPSBO (odds ratio [OR] = 1.612, 95% [CI]: 1.102–1.605). ROC curve analysis demonstrated high sensitivity (92%) and specificity (100%) for the V/S ratio in predicting EPSBO, with a 0.83 AUC.
Conclusions
Our findings indicated a higher V/S ratio was a significant predictor of EPSBO following total gastrectomy for cardia cancer. Preoperative assessment of the V/S ratio can inform risk stratification and guide targeted interventions to improve postoperative outcomes.
Keywords
Introduction
Early postoperative small bowel obstruction (EPSBO) is a serious complication arising within the first 30 days after a surgical procedure 1 that poses considerable clinical challenges, particularly following total gastrectomy for cardia cancer. 2 EPSBO is typically characterized by crampy abdominal pain, vomiting, and radiographic findings indicative of intestinal obstruction, occurring after the initial return of intestinal function post-surgery. 3 Cardia cancer often necessitates total gastrectomy, a major surgical intervention with a noteworthy incidence of EPSBO. 4 This complication is frequently induced by postoperative adhesions, 5 which are believed to result from a local inflammatory reaction to surgical invasion. 6 The pathophysiological mechanisms underlying adhesion formation have been partially elucidated, pointing to the pivotal roles of interferon gamma (IFN-γ) produced by natural killer T (NKT) cells and the enhanced expression of plasminogen activator inhibitor type 1 (PAI-1). 7 These factors contribute substantially to the adhesion process and subsequent bowel obstruction. 8 Risk factors for developing postoperative small bowel obstruction have been identified in several studies. 9 Although male sex has been repeatedly reported as a risk factor, the reasons underlying this association have not been thoroughly investigated. 10 One pertinent hypothesis posits that the variance in EPSBO risk between sexes is linked to differences in body fat distribution. 11 Specifically, male individuals typically exhibit a higher visceral to subcutaneous fat area ratio (V/S ratio) compared with their female counterparts, a factor that may predispose them to EPSBO. 12
Visceral obesity, indicated by a high V/S ratio, is increasingly recognized as a risk factor for various postoperative complications. 13 For example, a high V/S ratio has been identified as a predictor of surgical site infection following gastrectomy. 14 Furthermore, evidence suggests that a high V/S ratio correlates more accurately with cardiometabolic risk than body mass index (BMI) and visceral fat area (VFA) alone. 15 Moreover, visceral obesity has been linked to increased PAI-1 expression, further implicating the V/S ratio in the pathogenesis of adhesions and EPSBO. 16 This underscores the importance of investigating the relationship between V/S ratio and EPSBO in patients undergoing total gastrectomy for cardia cancer. In this context, understanding the influence of visceral fat on postoperative outcomes can inform preoperative risk assessment and postoperative management to mitigate the risk of EPSBO. In this study, we aimed to prospectively examine the risks of developing EPSBO after total gastrectomy for cardia cancer and to assess the association between the V/S ratio and EPSBO.
Methods
Study population and data collection
We performed a retrospective analysis of all consecutive patients with cardia cancer who underwent elective total gastrectomy with esophagojejunostomy Roux-en-Y anastomosis without a stoma at the Thoracic Surgery Department of Nanjing Yimin Hospital between November 2019 and April 2024. All procedures in this study were conducted via the open surgical approach. Patients were divided into two groups based on the occurrence of EPSBO within the first 30 days following surgery. The exclusion criteria were patients with inflammatory bowel disease, a history of intraperitoneal irradiation, or unresectable peritoneal disseminated nodules.
The study endpoints comprised successfully capturing data at both entry and follow-up to ensure valid information regarding the diagnosis and management of EPSBO. Preoperative, intraoperative, and postoperative factors were meticulously monitored in this study. Preoperative factors included patient demographics such as age, sex, and BMI, as well as clinical history including previous abdominal surgery, American Society of Anesthesiologists (ASA) grade, tumor location, maximum tumor diameter, cancer stage, and bowel preparation using whole bowel irrigation. Intraoperative factors comprised the operative procedure, size of the abdominal incision, levels of lymph node dissection, operative time, estimated blood loss, infusion volume, transfusion, use of intraperitoneal irrigation, application of antiadhesive materials like sodium hyaluronate-based bioresorbable membrane, repositioning of the small intestine before wound closure, closure of mesenteric defects, and placement of intraperitoneal drains. Postoperative factors included wound infection (classified as Clavien–Dindo Grade ≥1), anastomotic leakage (Grade ≥2), and the use of epidural anesthesia. The relationship between these factors and the development of EPSBO was analyzed. Additionally, the impact of the V/S ratio on the occurrence of EPSBO was examined. Data on the incidence of EPSBO were collected through postoperative outpatient visits or telephone surveys. The V/S ratio was calculated using computed tomography (CT) scans at the umbilical level with specifically designed software, Slice-O-Matic. Preoperative staging CT scans, conducted within approximately 3 months prior to surgery, served as the basis for this analysis. Except for a few instances, non-contrast CT images were used for the Slice-O-Matic software. Fat areas were identified through a semiautomated segmentation process performed by two clinicians. We used the definition of anastomotic leakage (AL) established by the United Kingdom Surgical Infection Study Group (1991), which includes fecaloid discharge, fecal material emission from the wound, contrast extravasation on enema, postoperative peritonitis at reintervention, and/or fluid or air in the anastomotic region on CT.17,18
An exemption was received regarding ethical approval for this retrospective study from the Institutional Review Board of Nanjing Yimin Hospital. Written informed consent was obtained from all participants in the study. The investigators de-identified all patient information. The reporting of this study conforms to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. 19
Surgical technique
Initially, the patient is positioned supine under general anesthesia. An appropriate abdominal wall incision, typically a vertical midline incision in the upper abdomen, is selected based on the patient’s condition. The transverse colon is elevated, and the gastrocolic ligament is dissected along the avascular zone using electrocautery. Dissection proceeds through the anterior leaf of the transverse mesocolon to the anterior capsule of the pancreas, which is then cleared. The right gastroepiploic vessels, at the root of the upper margin of the pancreatic head, are ligated and divided. Lymph nodes in group 6 are removed along with associated lymphatic and connective tissues at the anterior wall of the duodenum. The duodenum is transected using a 6.0-cm linear cutter stapler and reinforced with interrupted 4-0 absorbable sutures. The right gastric vessels are ligated and divided. The hepatogastric ligament is dissected close to the liver with electrocautery, removing any enlarged lymph nodes. The stomach is retracted to the left, continuing the dissection of the anterior pancreatic capsule. Dissection extends along the common hepatic artery to the celiac trunk, where the left gastric vein is ligated and divided. The root of the left gastric artery is identified, double-ligated with locking clips, and divided.
The gastrosplenic ligament is opened, and locking clips are applied to the left gastroepiploic vessels, which are then divided along with the surrounding lymph nodes. The short gastric arteries are also clipped and divided. Dissection continues proximally toward the stomach, clearing groups 1 and 2 lymph nodes and surrounding tissues, and transecting the vagus nerve.
The esophagus is dissected free for approximately 7 cm. At a point 3.5 cm above the cardia, a purse-string clamp is applied, and the esophagus is transected. The entire stomach specimen is then removed. A 21-mm anvil head is inserted, the purse-string suture tightened, and the anvil head secured. The jejunal mesentery is incised 15 cm distal to the ligament of Treitz. The vascular arcades are ligated and divided. The jejunum is transected at this point. The distal jejunal segment is prepared with a 21-mm anastomotic stapler. An esophagojejunostomy is performed anterior to the colon, ensuring that the anastomotic margins are smooth and free of tension. Reinforcement is achieved with interrupted 4-0 absorbable sutures, and the jejunal stump is closed using a 6.0-cm linear cutter stapler. A side-to-side anastomosis between the proximal and distal jejunum is created 40 cm below the esophagojejunostomy. The distal jejunum is clamped with a purse-string clamp, and a 25-mm anvil head is placed. The proximal segment is also prepared with a 25-mm anastomotic stapler, and a jejunojejunostomy is performed. The seromuscular layer is reinforced with interrupted 4-0 absorbable sutures, and the proximal stump is closed using a 6.0-cm linear cutter stapler. Mesenteric defects are routinely closed with 4-0 absorbable sutures.
Statistical analysis
Continuous variables are reported as mean and standard deviation, and categorical variables are reported as number and percentage. The normality of the data was assessed using the D’Agostino–Pearson test. The Friedman test was used to analyze the changes in C-reactive protein (CRP) and procalcitonin (PCT) levels at specific time points. Nonparametric analysis was performed using the Mann–Whitney test to compare differences between groups. The diagnostic accuracy of CRP and PCT for detecting AL was determined by constructing a receiver operating characteristic (ROC) curve and calculating the area under the ROC curve (AUC). A p value of <0.05 was considered statistically significant. All statistical analyses were conducted using IBM SPSS software, version 26.0 (IBM Corp., Armonk, NY, USA).
Results
A total of 175 patients who underwent elective total gastrectomy for cardia cancer were included in this study. Among these, 27 patients (15.4%) developed EPSBO. The propensity-matched cohort consisted of 50 patients, with 25 in the EPSBO group and 25 in the non-EPSBO group. The demographic and clinical characteristics of the patients are summarized in Table 1. The mean age of patients in the EPSBO group was significantly higher than that in the non-EPSBO group (69.1 ± 5.3 years vs. 58.4 ± 9.7 years, p = 0.031). BMI was also significantly higher in the EPSBO group (28.5 ± 3.2 kg/m2 vs. 21.4 ± 8.1 kg/m2, p = 0.013). There were no significant differences in the sex distribution, tobacco use, or previous abdominal surgery between the two groups.
Comparison of clinical characteristics between patients in the EPSBO group and non-EPSBO group.
EPSBO, early postoperative small bowel obstruction; BMI, body mass index; ASA, American Society of Anesthesiologists; SD, standard deviation.
Perioperative indices were compared between the EPSBO and non-EPSBO groups, as shown in Table 2. The duration of the operation was significantly longer in the EPSBO group (204 ± 22.5 minutes vs. 175 ± 17.4 minutes, p = 0.021). There were no significant differences in white blood cell count, CRP levels, procalcitonin levels, albumin levels, hemoglobin levels, or estimated blood loss between the two groups. However, the incidence of wound infection and anastomotic leakage was significantly higher in the EPSBO group (wound infection: 5 [20%] vs. 2 [8%], p = 0.023; anastomotic leakage: 6 [24%] vs. 3 [12%], p = 0.016).
Comparison of perioperative indices between patients in the EPSBO group and non-EPSBO group.
Values in the table are mean ± standard deviation unless otherwise noted.
EPSBO, early postoperative small bowel obstruction.
The abdominal anatomical characteristics, including the subcutaneous fat area (SFA), VFA, and V/S ratio, were compared between the EPSBO and non-EPSBO groups (Table 3). The VFA was significantly higher in the EPSBO group (895.46 ± 85.65 cm2 vs. 727.06 ± 45.54 cm2, p = 0.006). The V/S ratio was also significantly higher in the EPSBO group (1.76 ± 1.05 vs. 1.01 ± 0.54, p = 0.029). There was no significant difference in SFA between the two groups.
Comparison of abdominal anatomical characteristics between patients in the EPSBO group and non-EPSBO group
EPSBO, early postoperative small bowel obstruction; SD, standard deviation.
Logistic regression analysis was performed to identify risk factors for EPSBO (Table 4). The analysis revealed that anastomotic leakage (OR = 1.206, 95% CI: 1.098–1.575, p = 0.037), duration of operation (OR = 1.034, 95% CI: 0.802–1.082, p = 0.021), VFA (OR = 1.069, 95% CI: 0.903–1.183, p = 0.003), and V/S ratio (OR = 1.612, 95% CI: 1.102–1.605, p = 0.013) were significant predictors of EPSBO.
Results of logistic regression for risk factors of early postoperative small bowel obstruction.
OR, odds ratio; CI, confidence interval; V/S ratio, visceral to subcutaneous fat area ratio.
The predictive value of the V/S ratio for EPSBO was further evaluated using ROC curve analysis (Table 5, Figure 1). The V/S ratio demonstrated a high sensitivity (92%) and specificity (100%) for predicting EPSBO, with an AUC of 0.83 (p = 0.016). The optimal cut-off value for the V/S ratio was determined to be 1.82. In addition to the V/S ratio, other parameters were also evaluated for their predictive value. The duration of operation showed a sensitivity of 89% and specificity of 96.04% with an AUC of 0.71 (p = 0.034), indicating that longer operative times are a significant predictor of EPSBO. Anastomotic leakage had a sensitivity of 78% and specificity of 72.54%, with an AUC of 0.58 (p = 0.042), suggesting a moderate predictive value. The VFA demonstrated a sensitivity of 77% and specificity of 78.94%, with an AUC of 0.65 (p = 0.043), indicating that a higher VFA is associated with an increased risk of EPSBO.
Factors predicting early postoperative small bowel obstruction.
UC, area under the receiver operating characteristic curve; V/S ratio, visceral to subcutaneous fat area ratio.

ROC analysis of risk factors for EPSBO prediction. ROC curves for anastomotic leakage, V/S ratio, duration of operation, and VFA in predicting EPSBO in patients receiving elective total gastrectomy with esophagojejunostomy Roux-en-Y anastomosis. ROC, receiver operating characteristic; VFA, visceral fat area; EPSBO, early postoperative small bowel obstruction; V/S ratio, visceral to subcutaneous fat area ratio.
Discussion
In this study, we aimed to elucidate the relationship between the V/S ratio and the incidence of EPSBO following total gastrectomy for cardia cancer. Our findings indicate that a higher V/S ratio is a significant predictor of EPSBO, corroborating the hypothesis that visceral obesity plays a crucial role in postoperative complications.
Our analysis revealed that patients who developed EPSBO had a significantly higher V/S ratio compared with those who did not (1.76 ± 1.05 vs. 1.01 ± 0.54, p = 0.029). This finding aligns with previous studies that have identified visceral obesity as a risk factor for various postoperative complications, including surgical site infections and cardiometabolic risks.14,15 The V/S ratio demonstrated high sensitivity (92%) and specificity (100%) for predicting EPSBO, with an AUC of 0.83, indicating its robust predictive value.
In logistic regression analysis, we further identified anastomotic leakage, the duration of operation, VFA, and V/S ratio as significant predictors of EPSBO. Specifically, the V/S ratio had an OR of 1.612 (95% CI: 1.102–1.605, p = 0.013), underscoring its importance in the pathogenesis of EPSBO. These results suggest that the V/S ratio could serve as a valuable preoperative risk assessment tool, enabling clinicians to identify high-risk patients and implement targeted interventions to mitigate the risk of EPSBO.
The pathophysiological mechanisms underlying the association between a high V/S ratio and EPSBO may involve several factors. Visceral obesity increases the expression of PAI-1, which plays a pivotal role in adhesion formation and subsequent bowel obstruction.20,21 Additionally, the local inflammatory response to surgical invasion, mediated by IFN-γ that is produced by NKT cells, may be exacerbated in patients with greater visceral fat, further contributing to adhesion formation and EPSBO.22,23
The identification of the V/S ratio as a predictor of EPSBO has important clinical implications. Preoperative assessment of the V/S ratio using CT scans can help stratify patients based on their risk of developing EPSBO. For high-risk patients, strategies such as using meticulous surgical techniques to minimize tissue trauma, the use of antiadhesive materials, and enhanced postoperative monitoring may be warranted. Additionally, lifestyle interventions aimed at reducing visceral fat prior to surgery could potentially lower the risk of EPSBO.
Despite the strengths of this study, including a well-defined patient cohort and comprehensive data collection, several limitations should be acknowledged. The retrospective nature of the study may introduce selection bias, and the single-center design may limit the generalizability of the findings. Future prospective, multicenter studies are needed to validate these results and further explore the underlying mechanisms linking visceral obesity to EPSBO.24–26 Moreover, although the V/S ratio demonstrated high predictive value, it is essential to consider other potential risk factors and their interactions. Integrating the V/S ratio with other clinical parameters into a multifactorial risk assessment model could enhance its predictive accuracy and clinical utility.
Conclusion
This study provides compelling evidence that a higher V/S ratio is a significant predictor of EPSBO following total gastrectomy for cardia cancer. The V/S ratio offers a valuable preoperative risk assessment tool that can inform clinical decision-making and guide targeted interventions to improve postoperative outcomes. Further research is warranted to validate these findings and explore strategies to mitigate the risk of EPSBO in high-risk patients.
Footnotes
Acknowledgements
The authors would like to thank the patients for their cooperation and consent for the publication of this report.
Author contributions
Changfeng Fan drafted the manuscript and performed the literature review. Hailu Yang analyzed the data and approved the final manuscript.
Data availability statement
The datasets used or analyzed during the current study are available from the corresponding author on reasonable request.
Declaration of conflicting interest
The authors declare that there is no conflict of interest.
Funding
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
