Oncometabolic surgery: Emergence and legitimacy for investigation

The Metabolic Effects and Effectiveness of the Different Reconstruction Methods used in Gastric Cancer Surgery: A Systematic Review and Meta-Analysis

Gastric Cancer (GC) is the fifth most common cancer worldwide. Early stages of GC began being detected, giving rise to a new concern, Quality of Life. This study aimed to systematically assess the effects of different GC reconstruction techniques on postoperative type 2 diabetes mellitus (T2DM), hypertension (HBP), and body mass index (BMI) reduction rate and to provide an overview of recent research on oncometabolic surgery (OS). We performed a systematic review and meta-analysis by searching three databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We performed a meta-analysis of risk ratios and mean differences to estimate the impact of duodenal bypass, Roux-en-Y reconstruction, and residual stomach on T2DM, HBP, and BMI reduction rate. Heterogeneity was assessed using the I2 statistics. At the end of the follow-up, the duodenal bypass group compared to Billroth I had a significantly higher postoperative remission of T2DM and HBP, with a relative risk (RR) of 1.43 (95% confidence interval (95% CI) [1.27; 1.62]) and 1.3 (95% CI [1.00; 1.69]), respectively. Compared with the Billroth II group, Roux-en-Y reconstruction had significantly greater T2DM remission after gastrectomy (RR = 1.19; 95% CI [1.08; 1.31]), while HBP showed no significant differences. Regarding the improvement of HBP, total gastrectomy was significantly superior to subtotal gastrectomy (95% CI [1.01; 2.64]). A trend towards Roux-en-Y Esophagojejunostomy as the best option for T2DM remission was observed (95% CI [0.98; 2.77]; p = 0.06). Gastrectomy with Roux-en-Y reconstruction appears to be the most effective treatment for T2DM remission. Further research is needed to assess the impact of OS on metabolic diseases.

Comparative Risk of Type 2 Diabetes after Gastrectomy and Endoscopic Resection for Gastric Cancer: A Nationwide Cohort Study

BACKGROUND

Patients with gastric cancer (GC) experience 2 characteristic treatment modalities (gastrectomy or endoscopic resection), which may induce heterogeneity in the risk of post-cancer treatment type 2 diabetes (T2D). We investigated differences in the risk for T2D development in survivors of GC according to the 2 treatment methods.

STUDY DESIGN

This retrospective nationwide population-based cohort study included 14,646 patients with GC who underwent gastrectomy (n = 12,918) or endoscopic resection (n = 1,728). We enrolled patients who survived for at least 5 years after gastrectomy or endoscopic resection, had no history of diabetes, and had not received adjuvant chemotherapy. T2D risk was evaluated using Cox regression for the gastrectomy group and compared to that of the endoscopic resection group. Because of the competing risks of incident T2D and death, a competing risk regression was performed.

RESULTS

After a median follow-up duration of 8.1 years, the incidence rates of T2D in the endoscopic resection group and gastrectomy group were 7.58 and 6.98 per 1,000 person-years, respectively. Patients undergoing gastrectomy showed a significantly higher risk for developing T2D than patients undergoing endoscopic resection (hazard ratio [HR], 1.37; 95% CI 1.18 to 1.58; p < 0.0001). In subgroup analyses, gastrectomy was associated with increased T2D risk in female patients (HR, 1.72; 95% CI 1.22 to 2.43; p = 0.030 for interaction).

CONCLUSIONS

Among GC survivors, patients undergoing gastrectomy showed a 37% increased risk of T2D development compared to patients undergoing endoscopic resection. Subgroup analyses showed that T2D risk increased by up to 72% in female patients. These results provide insights for establishing screening and preventive strategies for GC survivors to prevent T2D according to different treatment modalities.

Diabetes Mellitus and Gastric Cancer: Correlation and Potential Mechanisms

This review summarizes the correlation between diabetes mellitus (DM) and gastric cancer (GC) from the perspectives of epidemiology, drug use, and potential mechanisms. The association between DM and GC is inconclusive, and the positive direction of the association reported in most published meta-analyses suggests that DM may be an independent risk factor for GC. Many clinical investigations have shown that people with DM and GC who undergo gastrectomy may have better glycemic control. The potential link between DM and GC may involve the interaction of multiple common risk factors, such as obesity, hyperglycemia and hyperinsulinemia, H. pylori infection, and the use of metformin. Although in vitro and in vivo data support that H. pylori infection status and metformin can influence GC risk in DM patients, there are conflicting results. Patient survival outcomes are influenced by multiple factors, so further research is needed to identify the patients who may benefit.

The association between weight change after gastric cancer surgery and type 2 diabetes risk: A nationwide cohort study

BACKGROUND

Although gastric cancer patients generally experience drastic weight decrease post-gastrectomy, the impact of weight decrease on type 2 diabetes risk remains unclear. We investigated the type 2 diabetes risk after gastric cancer surgery according to postoperative weight decrease in gastric cancer survivors in South Korea, the country with the world's highest rate of gastric cancer survival.

METHODS

This retrospective nationwide cohort study included gastric cancer surgery recipients between 2004 and 2014 who survived for ≥5 years post-surgery. We included patients without a history of diabetes at the time of surgery and those who had not received adjuvant chemotherapy before or after the surgery. Postoperative weight loss was defined as the per cent body weight loss at 3 years post-surgery compared with the baseline. The type 2 diabetes risk was evaluated using Cox regression analyses for five groups of postoperative weight decrease.

RESULTS

In 5618 included gastric cancer surgery recipients (mean age, 55.7 [standard deviation, SD, 10.9] years; 21.9% female; mean body mass index, 23.7 [SD, 2.9] kg/m² ), 331 patients (5.9%) developed postoperative type 2 diabetes during follow-up duration of 8.1 years (median; interquartile range, 4.8 years; maximum, 15.2 years). Compared with those who gained weight post-surgery, patients with ≥ -15% to < -10% of postoperative weight decrease (hazard ratio, 0.65; 95% confidence interval, 0.49-0.87; P = 0.004) had the lowest type 2 diabetes risk. A non-linear association occurred between postoperative weight decrease and the type 2 diabetes risk in gastrectomy recipients (Akaike's information criterion [AIC] for non-linear model, 5423.52; AIC for linear model, 5425.61).

CONCLUSIONS

A U-shaped non-linear association occurred between the type 2 diabetes risk and postoperative weight decrease in gastric cancer survivors who underwent gastrectomy. The lowest type 2 diabetes risk occurred in patients with ≥ -15% to < -10% of postoperative weight decrease at 3 years.

Prediction of antidiabetic effect after gastrectomy with Roux-en-Y reconstruction in patients with gastric cancer and type 2 diabetes

This study investigated the antidiabetic outcomes after gastrectomy with long-limb RY reconstruction (LRYR) and the prognostic factors for remission after 1 year in patients with type 2 diabetes (T2DM) and gastric cancer. In 25 Koreans with T2DM and gastric cancer, plasma glucose and insulin levels were measured during a 75 g oral glucose tolerance test, before and 1 week after gastrectomy with LRYR. Patients were examined after 1 year and we defined glycemic control as "remission" when the HbA1c level after 1 year was <6.0% without medication. One year after surgery, 12 patients achieved HbA1c < 6.0% without medication. Among the preoperative indices, the duration of diabetes was shorter in the remission group than that in the non-remission group (median 2.0 [0-6.5] years vs 7.0 [4.5-10.0] years, P = .023). At 1 week after surgery, significant improvements in fasting, 30 minutes, 60 minutes, 90 minutes stimulated glucose levels and insulin resistance (HOMA-IR and Matsuda index) were found only in the remission group. The multivariable logistic regression analysis results showed that higher 30 minutes stimulated glucose level and HOMA-IR index at 1 week after surgery were independent factors for lower odds of 1-year diabetes remission. Shorter duration of diabetes and early postoperative improvements in 30 minutes stimulated glucose level and HOMA-IR were important determinants of long-term antidiabetic outcomes after gastrectomy with LRYR in patients with T2DM and gastric cancer.

Impact of Preoperative Type 2 Diabetes Mellitus on the Outcomes of Gastric Cancer Patients Following Gastrectomy: A Propensity Score Matching Analysis

Purpose

The current study aims to explore the outcomes of type 2 diabetes mellitus (T2DM) on gastric cancer patients following gastrectomy through propensity score matching (PSM) analysis.

Methods

A retrospective study of gastric cancer patients following gastrectomy was conducted in a single clinical center from January 2014 to December 2019. The short-term outcomes, overall survival (OS) and disease-free survival (DFS) were analyzed between T2DM group and Non-T2DM group.

Results

A total of 703 patients were enrolled in this study. After 1:1 PSM, 84 patients in T2DM group and 84 patients in Non-T2DM were matched for final analysis. No significant difference was found in terms of operation time, intra-operative blood loss, retrieved lymph nodes, postoperative stay, blood transfusion and complications between T2DM group and Non-T2DM group (p > 0.05). The Kaplan-Meier curve implied that T2DM had no impact on OS or DFS. Cox regression was conducted to identify predictive factors for prognosis. Body mass index (BMI) (p = 0.039 < 0.05, HR = 0.725, 95% CI = 0.534–0.983), pre-operative lymphocyte (p = 0.017 < 0.05, HR = 0.678, 95% CI = 0.493–0.932), pathological tumor node metastasis (pTNM) stage (p = 0.000 < 0.05, HR = 2.619, 95% CI = 2.048–3.349) and complications (p = 0.006 < 0.05, HR = 1.528, 95% CI = 1.132–2.061) were predictive factors for OS, and BMI (p = 0.013 < 0.05, HR = 0.524, 95% CI = 0.315–0.872), pTNM stage (p = 0.000 < 0.05, HR = 2.619, 95% CI = 2.048–3.349) and complications (p = 0.008 < 0.05, HR = 1.892, 95% CI = 1.179–3.036) were independent predictive factors for DFS.

Conclusion

T2DM did not have an impact on gastric cancer patients following gastrectomy in terms of short-term outcomes and prognosis.

Hypertension Remission after Colorectal Cancer Surgery: A Single-Center Retrospective Study

The purpose of this study was to evaluate the effect of colorectal cancer surgery on hypertension. Patients who underwent colorectal cancer surgery were retrospectively enrolled. Hypertension before and 1 year after colorectal cancer surgery was recorded. As a result, eighty patients had remission of hypertension, 307 patients had no remission 1 year after colorectal cancer surgery, and the remission rate was 20.7%. In conclusion, patients with concurrent colorectal cancer and hypertension had a 20.7% remission rate 1 year after colorectal cancer surgery. Age, but not the type of surgery, was a predictive factor for the remission of hypertension.

Effect of oncometabolic surgery on gastric cancer: The remission of hypertension, type 2 diabetes mellitus, and beyond

This review summarizes the definition and surgical methods of oncometabolic surgery according to previous studies. Then, the authors discuss the beneficial effects observed after gastrectomy in gastric cancer (GC) patients with concurrent hypertension or type 2 diabetes mellitus (T2DM). The authors summarize the current studies analyzing the remission rate and the hypotheses of the mechanisms underlying these effects. The remission rate ranged from 42.5%-65.4% in T2DM patients and from 11.1%-57.6% among those with hypertension. Furthermore, the remission of T2DM could have an impact on overall survival rates as well. The mechanisms underlying the remission of hypertension and T2DM is unclear in current studies, but oncometabolic surgery is expected to be applied in clinical practice. In addition, the effect of oncometabolic surgery on other chronic metabolic comorbidities is expected to be proven in further studies. Therefore, the purpose of this review is to discuss the effects of oncometabolic surgery reported in current studies with a primary focus on the remission of hypertension and T2DM after gastrectomy in GC patients. The possibility of the remission of other metabolic comorbidities in GC patients who undergo oncometabolic surgery is also discussed.

The Relationship between Diabetes Mellitus and Gastric Cancer and the Potential Benefits of Metformin: An Extensive Review of the Literature

The objective of this review is to summarize the findings of published research that investigated the relationship between diabetes mellitus and gastric cancer (GCa) and the potential benefits of metformin on GCa. Related literature has been extensively reviewed, and findings from studies investigating the relationship between diabetes mellitus and GCa suggest that hyperglycemia, hyperinsulinemia and insulin resistance are closely related to the development of GCa. Although not supported by all, most observational studies suggest an increased risk of GCa in patients with type 2 diabetes mellitus, especially in women and in Asian populations. Incidence of second primary malignancy diagnosed after GCa is significantly higher in diabetes patients. Diabetes patients with GCa may have more complications after gastrectomy or chemotherapy and they may have a poorer prognosis than patients with GCa but without diabetes mellitus. However, glycemic control may improve in the diabetes patients with GCa after receiving gastrectomy, especially after procedures that bypass the duodenum and proximal jejunum, such as Roux-en-Y gastric bypass or Billroth II reconstruction. The potential links between diabetes mellitus and GCa may involve the interactions with shared risk factors (e.g., obesity, hyperglycemia, hyperinsulinemia, insulin resistance, high salt intake, smoking, etc.), Helicobacter pylori (HP) infection, medications (e.g., insulin, metformin, statins, aspirin, proton pump inhibitors, antibiotics, etc.) and comorbidities (e.g., hypertension, dyslipidemia, vascular complications, heart failure, renal failure, etc.). With regards to the potential benefits of metformin on GCa, results of most observational studies suggest a reduced risk of GCa associated with metformin use in patients with T2DM, which can be supported by evidence derived from many in vitro and animal studies. Metformin use may also reduce the risk of HP infection, an important risk factor of GCa. In patients with GCa, metformin users may have improved survival and reduced recurrence. More studies are required to clarify the pathological subtypes/anatomical sites of GCa associated with type 2 diabetes mellitus or prevented by metformin, to confirm whether GCa risk can also be increased in patients with type 1 diabetes mellitus and to explore the possible role of gastric microbiota in the development of GCa.