Does obesity affect outcomes in patients undergoing esophagectomy for cancer? A meta-analysis

Global trends in esophageal cancer and metabolic syndrome research: bibliometric analysis and visualization from 1995 to 2024

PURPOSE

Metabolic syndrome (MetS) plays a key role in the progression of esophageal cancer (EC), yet few studies have comprehensively explored research trends on this topic. To fill this gap, this study analyzes global research developments, hotspots, and collaborations related to MetS and EC.

METHODS

A total of 1008 publications from 1995 to 2024 were analyzed using bibliometric tools like VOSviewer, CiteSpace, and the R package 'bibliometrix', drawing from the Web of Science Core Collection.

RESULTS

The analysis includes contributions from 5,183 researchers at 1500 institutions across 85 countries, with publications appearing in 411 journals. The United States, China, and the United Kingdom are leading in both publication volume and research impact. Karolinska Institutet emerged as a prominent contributor to this body of work. Key journals include the Diseases of the Esophagus and Gastroenterology. Main areas cover metabolic factors, metabolic surgery, adipokines, lifestyle risk factors, cirrhosis & portal hypertension. Emerging trends focus on "metabolic syndrome and EC risk", "inflammation and adipokines", "bariatric surgery and EC prevention", "post-surgical outcomes", "early detection strategies".

CONCLUSION

As the first comprehensive bibliometric study on MetS and EC, this research highlights metabolism-related factors driving EC progression. Future research should focus on clarifying MetS-EC mechanisms and developing prevention and treatment strategies.

Cross-Talk Between Cancer and Its Cellular Environment-A Role in Cancer Progression

The tumor microenvironment is a dynamic and complex three-dimensional network comprising the extracellular matrix and diverse non-cancerous cells, including fibroblasts, adipocytes, endothelial cells and various immune cells (lymphocytes T and B, NK cells, dendritic cells, monocytes/macrophages, myeloid-derived suppressor cells, and innate lymphoid cells). A constantly and rapidly growing number of studies highlight the critical role of these cells in shaping cancer survival, metastatic potential and therapy resistance. This review provides a synthesis of current knowledge on the modulating role of the cellular microenvironment in cancer progression and response to treatment.

A scoping review of preoperative weight loss interventions on postoperative outcomes for patients with gastrointestinal cancer

BACKGROUND

Obesity is associated with increased risk of surgical complications in some settings.

OBJECTIVE

As a precursor to a systematic review, we conducted a scoping review of intentional preoperative weight loss to describe these interventions, their feasibility and effectiveness for patients with gastrointestinal cancer.

METHODS

In April 2024, Ovid MEDLINE, EMBASE, CINAHL, and Google Scholar were searched for primary studies of intentional weight loss before elective gastrointestinal cancer surgery. Extracted data encompassed recruitment and attrition, intervention types, adherence, anthropometric and body composition changes, and surgical outcomes. Study quality was assessed using the Risk of Bias In Non-randomized Studies of Interventions tool.

RESULTS

The search produced 7 articles (4 non-randomized clinical trials), which were all conducted in Japan, and involved 258 participants with a baseline BMI ≥25 kg/m2. Weight loss interventions included dietary modification (n = 3), exercise (n = 1), and combination (n = 3). None of the articles reported rates of recruitment, 2 adherence (97-100 %), and 4 reported attrition rates (0-18 %). All reported weight reductions of -1.3 to -6 kg and 4.5-6.9 % (n = 7), compared to baseline. Three of four non-randomized trials observed a reduction in postoperative complications, as compared to control; yet all trials were at critical risk of bias.

CONCLUSION

Strong conclusions could not be made due to the limited reporting and critical risk of bias; further systematic review is not recommended at this time. To establish more robust evidence, there is a clear need for high-quality trials.

Impact of Morbid Obesity on Post-esophagectomy Leak Rate: a NSQIP Analysis

BACKGROUND

Morbid obesity is becoming more prevalent and is a known risk factor for esophageal cancer. Esophagectomy in this population is technically more challenging than the non-obese, thus increasing the risks of surgery. This study hypothesizes that higher body mass index (BMI) is associated with higher anastomotic leak rates after esophagectomy.

METHODS

This study is a retrospective review of patients undergoing esophagectomy in the National Surgical Quality Improvement Program (NSQIP) Targeted Esophagectomy database from 2016 to 2019. Patients were stratified by BMI < 35 versus BMI > 35, with the primary outcome being leak post-esophagectomy. Univariate analyses were performed for demographics and post-operative outcomes, and multivariate analyses were performed specifically for the primary outcome of anastomotic leak (all diagnoses and malignancy/dysplasia subgroup). This study was approved by the Institutional Review Board.

RESULTS

Of 4165 patients, 439 (10.5%) had a BMI > 35. Patients with BMI > 35 were often younger (mean age 60 vs 64 years, p < 0.001), White (p < 0.001), female (p < 0.001), non-smoker (p < 0.001), diabetic (p < 0.001), with hypertension (p < 0.001), and ASA ≥ 3 (p < 0.001). There were no differences between BMI groups with regard to indication for esophagectomy (malignancy/dysphasia vs other), conversion to open, mortality, or length of stay. The BMI > 35 cohort reported higher operative times (p < 0.001), open operative approach (p = 0.04), superficial surgical site infection (p < 0.001), return to operating room (p = 0.01), and leak (13.5% vs 10.1%, p = 0.01). BMI > 35 was not an independent predictor of leak for all diagnoses; however, the subgroup analysis of esophagectomy for malignancy/dysplasia demonstrated that BMI > 35 was predictive of leak (OR 1.42, 95% CI 1.05-1.91), as well as operative time and hypertension.

CONCLUSION

Patients with a BMI > 35 and who undergo esophagectomy have a higher rate of anastomotic leak. BMI > 35 was also an independent predictor of leak when esophagectomy was performed for malignancy/dysplasia, but not for all diagnoses. The risk of anastomotic leak should be considered in morbidly obese patients undergoing esophagectomy, particularly for malignancy.

Obesity paradox as a new insight from postoperative complications in gastric cancer

The obesity paradox is reported to exist in various diseases. However, obesity is a pivotal issue in gastric cancer (GC) patients because of the surgical difficulty related to postoperative abdominal infectious complications (PAIC). This study clarified the existence of the obesity paradox in GC. Between 1997 and 2015, 1536 consecutive patients underwent curative gastrectomy. Of all patients, 18.6% (285/1536) were obese and tended to have a better prognosis (P = 0.073). In patients without PAIC, obesity was a significant prognostic factor for 5-year overall survival (P = 0.017). PAIC was an independent poor prognostic factor in both obese and non-obese patients (P < 0.001; hazard ratio [HR] 4.22 and 1.82). In pStage II-III patients, there was a large and significant prognostic difference between non-PAIC and PAIC obese patients (P = 0.006; 5-year overall survival: 69.7% vs. 43.8%) related to the higher incidence of peritoneal recurrence in PAIC obese patients (P = 0.035; 31% vs. 10%). Whereas, there was a small prognostic difference between non-PAIC and PAIC non-obese patients (P = 0.102; 5-year overall survival: 56.5% vs. 51.9%). Although the obesity paradox is present in GC, PAIC had a more negative prognostic impact through peritoneal recurrence in obese GC patients.

An Association Between Comorbidities and Postsurgical Complications in Adults Who Underwent Esophagectomy

Background Esophagectomy is the surgical excision of part or all of the esophagus and is associated with both common and serious complications. Various comorbidities, such as diabetes mellitus, smoking, and congestive heart failure (CHF), have been detected in individuals who have undergone esophagectomy. This study investigates the association of baseline characteristics and comorbidities with postoperative complications. Methods A retrospective cohort study based on data from the National Surgical Quality Improvement Program database was conducted, evaluating 2,544 patients who underwent esophagectomy between January 2016 and December 2018. Data included baseline characteristics, established comorbidities, and postoperative complications within 30 days of the procedure. Risk-adjusted and unadjusted logistic regressions were used to assess the odds of postoperative complications against baseline characteristics. Results The majority of our population were white males (80.8% male; 78.2% white), with a mean age of 63.5 years. More than half of the patients were overweight or obese. A minority of our patients had a smoking history, weight loss, diabetes mellitus, chronic obstructive pulmonary disease (COPD), or CHF. The most frequent postoperative complications were as follows: return to the operating room (15.7%), anastomotic leak (12.9%), pneumonia (12.7%), bleeding/transfusions (11.8%), readmissions (11.4%), and unplanned intubation (10.5%). Adjusted associations for odds of experiencing a postoperative complication were found to be statistically significant for age (odds ratio [OR] 1.02, 95% confidence interval [CI] 1.01-1.03, and P < 0.001), operation time (OR 1.002, 95% CI 1.001-1.003, and P < 0.001), race (not white) (OR 1.76, 95% CI 1.26-2.47, and P = 0.001), BMI (underweight) (OR 2.18, 95% CI 1.36-3.50, and P = 0.001), smoking (OR 1.42, 95% CI 1.14-1.76, and P = 0.001), and chemotherapy and/or radiation (OR 0.82, 95% CI 0.68-0.99, P = 0.038). Conclusions Our study found that age, operation time, nonwhite race, underweight BMI, and smoking were independently associated with an increased risk of developing a postoperative complication following esophagectomy. Additionally, neoadjuvant chemotherapy and/or radiation are associated with a decreased risk. Understanding how baseline characteristics and comorbidities can affect rates of postoperative complications may help to adjust care for patients in both pre- and postoperative settings.

Obesity Paradox: Fact or Fiction?

PURPOSE OF REVIEW

Obesity is related to several comorbidities such as type 2 diabetes mellitus, cardiovascular disease, heart failure, and various types of cancers. While the detrimental effect of obesity in both mortality and morbidity has been well established, the concept of the obesity paradox in specific chronic diseases remains a topic of continuous interest. In the present review, we examine the controversial issues around the obesity paradox in certain conditions such as cardiovascular disease, several types of cancer and chronic obstructive pulmonary disease, and the factors that may confound the relation between obesity and mortality.

RECENT FINDINGS

We refer to the obesity paradox when particular chronic diseases exhibit an interesting "paradoxical" protective association between the body mass index (BMI) and clinical outcomes. This association, however, may be driven by multiple factors among which the limitations of the BMI itself; the unintended weight loss precipitated by chronic illness; the various phenotypes of obesity, i.e., sarcopenic obesity or the athlete's obesity phenotype; and the cardiorespiratory fitness levels of the included patients. Recent evidence highlighted that previous cardioprotective medications, obesity duration, and smoking status seem to play a role in the obesity paradox. The obesity paradox has been described in a plethora of chronic diseases. It cannot be emphasized enough that the incomplete information received from a single BMI measurement may interfere with outcomes of studies arguing in favor of the obesity paradox. Thus, the development of carefully designed studies, unhampered by confounding factors, is of great importance.

Effect of Body Composition Change during Neoadjuvant Chemotherapy for Esophageal Squamous Cell Carcinoma

Effects of changes in body composition during neoadjuvant chemotherapy (NAC) on perioperative complications and prognosis are unknown in patients with esophageal squamous cell carcinoma (ESCC). A total of 175 patients who underwent surgery for ESCC in our hospital between 2016 and 2019 were examined. The psoas muscle index (PMI) was calculated from the total psoas muscle area, and the visceral fat mass (VFM) at the umbilical level was measured. We defined body composition change (BCC) group as those with increased VFM of ≥ 3% and decreased PMI of ≥ 3% during NAC. Sarcopenia (S) was defined as PMI < 5.89 (male) and <4.06 (female). Nutritional assessment using the Subjective Global Assessment tool was performed upon admission. The percentages of BCC group, pre-NAC S, and post-NAC S was 32.5%, 79.4%, and 80.0%, respectively. BCC group had significantly more postoperative complications (p < 0.01) and longer hospital stays (p = 0.03) than groups pre-NAC S and post-NAC S. Overall survival (OS) analysis using the Cox hazard model showed that stage III (p < 0.01) and post-NAC S (p = 0.03) were poor prognostic factors. Changes in body composition during NAC affected perioperative complications and prognosis of patients with ESCC.

Impact of Excess Body Weight on Postsurgical Complications

BACKGROUND

Obesity is considered a risk factor for postoperative complications as it can limit exposure to the operation field, thereby significantly prolonging surgery time. Obesity-associated comorbidities, such as low-grade systemic inflammation, impaired functional status, and type 2 diabetes, are independent risk factors for impaired anastomotic wound healing and nonsurgical site infections. If obesity itself is an independent risk factor for surgical complications remains controversial, but the reason for this is largely unexplored.

SUMMARY

A MEDLINE literature search was performed using the terms: "obesity," "excess body weight," and "surgical complications." Out of 65,493 articles 432 meta-analyses were screened, of which 25 meta-analyses were on the subject. The vast majority of complex oncologic procedures in the field of visceral surgery have shown higher complication rates in obese patients. Meta-analyses from the last 10 to 15 years with high numbers of patients enrolled consistently have shown longer operation times, higher blood loss, longer hospital stay for colorectal procedures, oncologic upper gastrointestinal (GI) procedures, and pancreatic surgery. Interestingly, these negative effects seem not to affect the overall survival in oncologic patients, especially in esophageal resections. A selection bias in oncologic upper GI patients may have influenced the results with higher BMI in upper GI cancer to be a predictor for better nutritional and performance status.

KEY MESSAGES

Contrary to bariatric surgery, only limited evidence indicated that site and type of surgery, the approach to the abdominal cavity (laparoscopic vs. open), institutional factors, and the type of perioperative care such as ERAS protocols may play a role in determining postsurgical complications in obese patients. The initial question remains therefore partially unanswered. Large nationwide register-based studies are necessary to better understand which aspects of obesity and its related comorbidities define it as a risk factor for surgical complications.

Utility of feeding jejunostomy in patients with esophageal cancer undergoing esophagectomy with a high risk of anastomotic leakage

BACKGROUND

Feeding jejunostomy is widely used for enteral nutrition (EN) after esophagectomy; however, its risks and benefits are still controversial. We aimed to evaluate the short-term and long-term outcomes of feeding jejunal tube (FJT) in patients undergoing esophagectomy for esophageal squamous cell carcinoma (ESCC) who were deemed high-risk for anastomotic leakage.

METHODS

We retrospectively analyzed 716 patients who underwent esophagectomy with (FJT group, n=68) or without (control group, n=648) intraoperative placement of FJT. Propensity score matching (PSM) was used for the adjustment of confounding factors. Risk level for anastomotic leakage was determined for every patient after PSM.

RESULTS

Patients in the FJT group were at higher risk of anastomotic leakage (14.9% vs. 11.3%), and had a statistically non-significant increase of postoperative complications [31.3% vs. 21.8%, odds ratio (OR) =1.139, 95% confidence interval (CI), 0.947-1.370, P=0.141] after PSM. Medical expenditure, length of postoperative hospital stay, and short-term mortality were similar between the FJT and control groups. Placement of FJT appeared to accelerate the recovery of anastomotic leakage (27.2 vs. 37.4 d, P=0.073). Patients in FJT group achieved comparable overall survival (OS) both before [hazard ratio (HR) =0.850, P=0.390] and after (HR =0.797, P=0.292) PSM.

CONCLUSIONS

FJT showed acceptable safety profile along with potential benefits for ESCC patients with a high presumed risk of anastomotic leakage. While FJT does not impact OS, placement of FJT should be considered in esophagectomy patients and tailored to individual patients based on their leak-risk profile.

The Obesity Paradox in Cancer: Epidemiologic Insights and Perspectives

PURPOSE OF REVIEW

Controversy exists whether excess body fatness (measured by body mass index (BMI)) is associated with better cancer survival ("obesity paradox"). Here, we review the obesity paradox in cancer research and discuss potential explanations and future research directions.

RECENT FINDINGS

Overweight and obese cancer patients have better survival for diverse cancers. This apparent obesity paradox may be largely explained by methodological limitations including reverse causation, selection bias, confounding, and reliance of BMI as a measure of adiposity in cancer patients. A growing number of studies show promising evidence that precisely quantified body composition can provide important prognostic information in cancer care, such that low muscle and high adiposity are associated with worse clinical outcomes in cancer patients. The term obesity paradox in cancer, implying a causally beneficial role of adiposity, is misleading. Understanding the role of muscle and adiposity may reduce the confusion and inform precision oncology care.

Obesity is Associated with Significantly More Anastomotic Leaks After Minimally Invasive Esophagectomy: A NSQIP Database Study

BACKGROUND

This study assessed the association between obesity status and postoperative outcomes for patients who underwent transthoracic esophagectomy (TTE) or transhiatal esophagectomy (THE) via an open or minimally invasive (MIE) surgical approach.

METHODS

The 2016-2018 national surgical quality improvement program esophagectomy-targeted database was used to identify adult patients who underwent TTE or THE, with stratification of patients by obesity status and surgical approach. Using a multivariable regression model for each outcome, the study evaluated whether the adjusted difference between obese and non-obese patients varied between the open and MIE approaches.

RESULTS

In this study, 1260 patients underwent TTE (28.1% obese; 51.7% MIE), and 386 patients underwent THE (29.3% obese; 43.0% MIE). The obese patients in the TTE cohort who underwent MIE had 3.4 times higher odds of failing to wean from mechanical ventilation within 48 h (95% confidence interval [CI] 1.8-6.4), 1.7 times greater odds of returning to the operating room (95% CI 1.1- 3.0), 2.4 times greater odds of having an index hospital stay longer than 30 days, (95% CI 1.0-6.0), and 2.5 times greater odds of experiencing a grade 3 anastomotic leak (95% CI 1.3-4.9). No differences between obese and non-obese patients were observed among those who underwent TTE via an open approach or THE.

CONCLUSIONS

The findings showed that obese patients undergoing TTE via an MIE approach had greater odds of failing to wean from mechanical ventilation within 48 h, returning to the operating room, having an index hospital stay longer than 30 days, and having a grade 3 anastomotic leak. These results are in contrast to the previously published literature and require replication as additional data become available.

Friend or foe: Multiple roles of adipose tissue in cancer formation and progression

Obesity is well-known as the second factor for tumorigenesis after smoking and is bound up with the malignant progression of several kinds of cancers, including esophageal cancer, liver cancer, colorectal cancer, kidney cancer, and ovarian cancer. The increased morbidity and mortality of obesity-related cancer are mostly attributed to dysfunctional adipose tissue. The possible mechanisms connecting dysfunctional adipose tissue to high cancer risk mainly focus on chronic inflammation, obesity-related microenvironment, adipokine secretion disorder, and browning of adipose tissue, and so forth. The stromal vascular cells in adipose tissue trigger chronic inflammation through secreting inflammatory factors and promote cancer cell proliferation. Hypertrophic adipose tissues lead to metabolic disorders of adipocytes, such as abnormal levels of adipokines that mediate cancer progression and metastasis. Cancer patients often show adipose tissue browning and cancerous cachexia in an advanced stage, which lead to unsatisfied chemotherapy effect and poor prognosis. However, increasing evidence has shown that adipose tissue may display quite opposite effects in cancer development. Therefore, the interaction between cancers and adipose tissue exert a vital role in mediates adipose tissue dysfunction and further leads to cancer progression. In conclusion, targeting the dysfunction of adipose tissue provides a promising strategy for cancer prevention and therapy.

Anastomotic leak and neoadjuvant chemoradiotherapy in esophageal cancer

Background

Anastomotic leaks (AL) cause significant morbidity after esophagectomy. Most patients receive neoadjuvant chemoradiation (NCR) prior to esophagectomy which has been associated with increase perioperative complications and mortality. We report on a comparison of AL rates in upfront surgical (UFS) and NCR patients.

Methods

An esophagectomy database was queried for UFS and NCR patients treated between 1996 and 2015. Predictors of AL rate were identified using univariate and multivariate (MVA) analysis and propensity score matching (PSM).

Results

We identified 820 patients (UFS, 288; NCR, 532). Overall AL rate was 5.4%. Decreased AL rate was observed in NCR patients on MVA (8.0% vs. 4.1%; P=0.02) but no difference was seen after PSM (7.7% vs. 4.2%; P=0.14). MVA of factors associated with decreased AL in UFS patients included distal esophageal tumors and body mass index (BMI) >25. Age, gender, year of surgery, histology, anastomotic location, and diabetes were not prognostic. Before PSM, MVA of NCR patients of factors associated with decreased AL revealed that only thoracic anastomosis was prognostic. However, this was not observed after PSM. MVA of factors associated with decreased AL in all patients revealed thoracic anastomosis, NCR, and BMI 25-30. After PSM, only distal esophageal tumors and thoracic anastomosis were prognostic for decreased AL.

Conclusions

There is no difference in the AL rate between UFS and NCR patients. Decreased AL rate was observed in patients with distal esophageal tumors and thoracic anastomosis.

Impact of high body mass index on surgical outcomes and long-term survival among patients undergoing esophagectomy: A meta-analysis

BACKGROUND

The impact of high body mass index (BMI, >23/25 kg/m) on surgical outcomes and prognosis in patients with esophageal carcinoma (EC) after undergoing esophagectomy remains controversial. We herein conducted a systematic review and meta-analysis to determine the relationship between high BMI and surgical outcomes and prognosis in patients undergoing esophagectomy for EC.

METHODS

The study search was conducted by retrieving publications from the PubMed, Embase, Web of Science, and CNKI (up to September 8, 2017). Nineteen studies with 13,756 patients were included in this meta-analysis.

RESULTS

We found that high BMI was closely associated with a higher incidence of wound infection (odds ratio [OR]: 1.41, 95% confidence interval [CI]: 1.02-1.97, P = .04), cardiovascular complications (OR: 2.51, 95% CI, 1.65-3.81, P < .0001), and anastomotic leakage (OR: 1.50, 95% CI, 1.21-1.84, P = .0002), but a lower incidence of chylous leakage (OR: 0.59, 95% CI, 0.40-0.88, P = .01) when compared with normal BMI. The high BMI group was not associated with better or worse overall survival (OS) (hazard ratio [HR]: 0.95, 95% CI, 0.85-1.07, P = .4) and disease-free survival (HR: 0.95, 95% CI, 0.72-1.25, P = .72) than the normal BMI group. However, in the subgroup analysis, the pooled result of HRs generated from multivariate analyses suggested that high BMI could improve OS in EC patients (HR: 0.84, 95% CI, 0.76-0.93, P < .01).

CONCLUSIONS

Overweight patients with EC should not be denied surgical treatment, but intraoperative prevention and careful postoperative monitoring for several surgical complications must be stressed for this population. Besides, high BMI might be a prognostic predictor in EC patients; further studies are warranted.

Thoracic Surgery Considerations in Obese Patients

The obesity epidemic in the United States has increased greatly over the past several decades, and thoracic surgeons are likely to see obese patients routinely in their practices. Obesity has direct deleterious health effects such as metabolic disorder and cardiovascular disease, and is associated with many cancers. Obese patients who need thoracic surgery pose practical challenges to many of the routine elements in perioperative management. Preoperative assessment of obesity-related comorbid conditions and risk stratification for surgery, thorough intraoperative planning for anesthesia and surgery, and postoperative strategies to optimize pulmonary hygiene and mobility minimize the risk of adverse outcomes.

Spirometric Lung Age Predicts Postoperative Pneumonia After Esophagectomy

BACKGROUND

Despite advances in treatment, postoperative pneumonia remains a major problem after esophagectomy. Lung age has been proposed as a comprehensive indicator for respiratory function. The aim of this study is to reveal the efficacy of lung age in predicting occurrence of pneumonia after esophagectomy.

METHODS

We assessed 342 consecutive patients who underwent subtotal esophagectomy for primary esophageal cancer from 2011 to 2014. Lung age was calculated from the preoperative spirometric test using the methods advocated by the Japanese Respiratory Society. We investigated factors predicting the occurrence of postoperative pneumonia after esophagectomy.

RESULTS

The incidence of postoperative pneumonia was 28.9 %. According to the Clavien-Dindo classification, grade II and grade III-V pneumonia were observed in 21.3 and 7.6 % patients, respectively. In multivariate logistic regression analysis for the factors predicting the occurrence of postoperative pneumonia, higher lung age (p = 0.010) and lower body mass index (p = 0.006) were independent factors. Patients with grade III-V pneumonia tended to have higher lung age than those with grade II pneumonia (p = 0.084). In addition, lung age was significantly higher in patients who experienced pneumonia within postoperative days 7 than those who experienced pneumonia after postoperative days 7 (p = 0.028).

CONCLUSION

Spirometric lung age was associated with occurrence, severity, and time of onset of postoperative pneumonia after esophagectomy. This simple parameter deserves a greater consideration as a predictor of postoperative pneumonia after esophagectomy and can support both surgeons and patients in understanding the status of respiratory function.

Oesophageal cancer

Oesophageal cancer is the sixth most common cause of cancer-related death worldwide and is therefore a major global health challenge. The two major subtypes of oesophageal cancer are oesophageal squamous cell carcinoma (OSCC) and oesophageal adenocarcinoma (OAC), which are epidemiologically and biologically distinct. OSCC accounts for 90% of all cases of oesophageal cancer globally and is highly prevalent in the East, East Africa and South America. OAC is more common in developed countries than in developing countries. Preneoplastic lesions are identifiable for both OSCC and OAC; these are frequently amenable to endoscopic ablative therapies. Most patients with oesophageal cancer require extensive treatment, including chemotherapy, chemoradiotherapy and/or surgical resection. Patients with advanced or metastatic oesophageal cancer are treated with palliative chemotherapy; those who are human epidermal growth factor receptor 2 (HER2)-positive may also benefit from trastuzumab treatment. Immuno-oncology therapies have also shown promising early results in OSCC and OAC. In this Primer, we review state-of-the-art knowledge on the biology and treatment of oesophageal cancer, including screening, endoscopic ablative therapies and emerging molecular targets, and we discuss best practices in chemotherapy, chemoradiotherapy, surgery and the maintenance of patient quality of life.

Variation by stage in the effects of prediagnosis weight loss on mortality in a prospective cohort of esophageal cancer patients

Cancer cachexia is increasingly recognized as a poor prognostic marker for various tumor types. Weight loss in esophageal cancer is multifactorial, as patients with bulky tumors also have reduced ability to eat. We aimed to investigate the relationship between prediagnosis weight loss and mortality in esophageal cancer and to determine whether these associations vary with tumor stage. We conducted a prospective cohort study of esophageal cancer patients at two tertiary centers. We recorded baseline patient characteristics including medications, smoking, body mass index, and weight loss in the year prior to diagnosis, and collected data on treatment and outcomes. We used Cox regression modeling to determine the associations between percent weight loss and outcomes. The main outcome of interest was all-cause mortality; secondary endpoints were esophageal cancer-specific mortality and development of metastases. We enrolled 134 subjects, the majority of whom had adenocarcinoma (82.1%); median percent weight loss was 4.7% (IQR: 0%-10.9%). Increasing percent weight loss was not associated with all-cause mortality (ptrend = 0.36). However, there was evidence of significant interaction by tumor stage (p = 0.02). There was a strong and significant association between prediagnosis weight loss and mortality in patients with T stages 1 or 2 (adjusted HR 8.26 for highest versus lowest tertile, 95%CI 1.11-61.5, ptrend = 0.03) but not for T stages 3 or 4 (ptrend = 0.32). Body mass index one year prior to diagnosis was not associated with mortality. Prediagnosis weight loss was associated with increased all-cause mortality only in patients with early stage esophageal cancer. This suggests that tumor-related cachexia can occur early in esophageal cancer and represents a poor prognostic marker.

Extremes of body mass index and postoperative complications after esophagectomy

Obesity has been variously associated with reduced or similar rates of postoperative complications compared to normal weight patients undergoing esophagectomy for cancer. In contrast, little is known about esophagectomy risks in the underweight population. The relationship between the extremes of body mass index (BMI) and postoperative complications after esophagectomy was evaluated. Consecutive esophagectomy patients (2000-2013) were reviewed. The patients were stratified based on BMI at the time of diagnosis: underweight (<18.5), normal (18.5-24.9), overweight (25-29.9), obese I (30-34.9), and obese II or III (≥35). Hospital length of stay as well as postoperative complications and their accordion severity grading were evaluated according to the BMI category. Of 388 patients, 78.6% were male with a median age of 62 years at the time of operation. Pathologic cancer stage was 0 to I in 53%. BMI distribution was as follows: 5.6% underweight, 28.7% normal, 31.4% overweight, 22.8% obese I, and 11.5% obese II or III. Performance status was 0 or 1 in 99.2%. Compared to normal BMI patients, underweight patients had increased pulmonary complications (odds ratio (OR) 3.32, P = 0.014) and increased other postoperative complications (OR 3.00, P = 0.043). Patients who were overweight did not have increased complications compared to normal BMI patients. BMI groups did not differ in mortality rates or complication accordion severity grading. Hospital length of stay trended toward a longer duration in the underweight population (P = 0.06). Underweight patients are at increased risk for postoperative pulmonary and other complications. Underweight patients may benefit from preoperative nutritional repletion and mitigation for sarcopenia. Aggressive postoperative pulmonary care may help reduce complications in these patients. In contrast, the operative risk in overweight and obese patients is similar to normal BMI patients.

Peculiarities of the obese patient with cancer: a national consensus statement by the Spanish Society for the Study of Obesity and the Spanish Society of Medical Oncology

The relationship between obesity and cancer is clear and is present at all times during course of the disease. The importance of obesity in increasing the risk of developing cancer is well known, and some of the most prevalent tumours (breast, colorectal, and prostate) are directly related to this risk increase. However, there is less information available on the role that obesity plays when the patient has already been diagnosed with cancer. Certain data demonstrate that in some types of cancer, obese patients tolerate the treatments more poorly. Obesity is also known to have an impact on the prognosis, favouring lower survival rates or the appearance of secondary tumours. In this consensus statement, we will analyse the scientific evidence on the role that obesity plays in patients already diagnosed with cancer, and the available data on how obesity control can improve the quality of daily life for the cancer patient.

Influence of body mass index on the long-term outcomes of patients with esophageal squamous cell carcinoma who underwent esophagectomy as a primary treatment: A 10-year medical experience

We explored the influence of body mass index (BMI) on long-term outcomes in patients with esophageal squamous cell carcinoma (ESCC) who underwent esophagectomy as a primary treatment. BMI is a risk factor for development of esophageal cancer. However, the details of the relationship between BMI and cancer prognosis remains unclear. Patients who underwent esophagectomy as an initial treatment in 2000 to 2009 period were included. The patients were divided into 3 groups according to Asian-specific BMI cut-offs. The associations between BMI and long-term outcomes were explored. This study included 1082 ESCC patients between 2000 and 2009; all the patients underwent esophagectomy. The median overall survival (OS) of the BMI <18.5, 18.5 ≤ BMI <23, and BMI ≥23 kg/m groups were 21, 24, and 29.5 months, respectively; they differed significantly (P = 0.005). The 5-year survival rates of the 3 groups were 24.6%, 30.4%, and 35.3%, respectively. Multivariate analysis showed that lower BMI was an independent risk factor for a shorter OS (18.5 ≤ BMI <23 kg/m vs. BMI ≥23 kg/m, hazard ratio [HR] = 1.18; 95% confidence interval [CI] = 1.00-1.40, P = 0.054, BMI <18.5 kg/m vs. BMI ≥23 kg/m, HR = 1.38; 95% CI = 1.09-1.75, P = 0.007). The better OS of the BMI ≥23 kg/m patients remained statistically significant in never-smoking patients (P < 0.05). In conclusion, patients with BMIs ≥23 kg/m experienced better OS, and multivariate analysis further indicated that BMI ≥23 kg/m was an independent predictor of survival. When stratified by smoking status, BMI ≥23 kg/m was still a factor in better OS among never smokers.

Understanding Complete Pathologic Response in Oesophageal Cancer: Implications for Management and Survival

Despite significant improvement over recent decades, oesophageal cancer survival rates remain poor. Neoadjuvant chemoradiotherapy followed by oesophageal resection is mainstay of therapy for resectable oesophageal tumours. Operative morbidity and mortality associated with oesophagectomy remain high and complications arise in up to 60% of patients. Management strategies have moved towards definitive chemoradiotherapy for a number of tumour sites (head and neck, cervical, and rectal) particularly for squamous pathology. We undertook to perform a review of the current status of morbidity and mortality associated with oesophagectomy, grading systems determining pathologic response, and data from clinical trials managing patients with definitive chemoradiotherapy to inform a discussion on the topic.

Influence of body mass index on outcomes after major resection for cancer

BACKGROUND

Evidence supporting worse outcomes among obese patients is inconsistent. This study examined associations between body mass index (BMI) and outcomes after major resection for cancer.

METHODS

Data from the 2005-2012 ACS-NSQIP were used to identify cancer patients (≥18 years) undergoing 1 of 6 major resections: lung surgery, esophagectomy, hepatectomy, gastrectomy, colectomy, or pancreatectomy. We used crude and multivariable regression to compare differences in 30-day mortality, serious and overall morbidity, duration of stay, and operative time among 3 BMI cohorts defined by the World Health Organization: normal versus underweight, overweight-obese I, and obese II-III. Propensity-scored secondary assessment and resection type-specific stratified analyses corroborated results.

RESULTS

A total of 529,955 patients met inclusion criteria; 32.06% had normal BMI, 3.45% were underweight, 32.52% overweight, and 17.76%, 7.51%, and 4.94% obese I-III, respectively. Risk-adjusted outcomes for underweight patients consistently were worse. Overweight-obese I fared similarly to patients with normal BMI but had greater odds of isolated complications. Obese II-III patients experienced only marginally increased odds of morbidity. Analyses among propensity-scored cohorts and stratified by cancer-resection type reported similar trends. Worse outcomes were observed among morbidly obese hepatectomy and pancreatectomy patients.

CONCLUSION

Evidence-based assessment of outcomes after major resection for cancer suggests that obese patients should be treated with the aim for optimal oncologic standards without being hindered by a misleading perception of prohibitively increased perioperative risk. Underweight and certain types of morbidly obese patients require targeted provision of appropriate care.

A high body mass index in esophageal cancer patients is not associated with adverse outcomes following esophagectomy

PURPOSE

There is no consensus about the impact of a high BMI on postoperative morbidity and survival after esophagectomy. The aim of this study was to determine the influence of a high BMI on postoperative complications and survival in a large cohort of esophageal cancer patients.

METHODS

From January 2006 to December 2012, 1,342 consecutive esophageal cancer patients who underwent esophagectomy were included in this study. Patients were divided into three groups: 950 patients were classified as normal BMI (BMI 18.5-24.9 kg/m(2)), 279 were classified as high BMI (BMI ≥ 25 kg/m(2)), and 113 as low BMI (BMI < 18.5 kg/m(2)). Multivariate logistic regression models were used to identify confounding factors associated with postoperative complications. The impact of BMI on overall survival (OS) was estimated by the Kaplan-Meier method and Cox proportional hazard models.

RESULTS

The predominance of pathological type was esophageal squamous cell carcinoma (n = 1,280, 95.4 %). Overall morbidity, mortality, and hospital stay did not differ among groups. The incidence of pneumonia was higher in patients with high BMI compared with those with normal BMI (14.7 vs. 9.9 %, P = 0.025). However, chylothorax was less frequent in high-BMI group (0.4 % in high-BMI group, 3.1 % in normal group, and 3.5 % in low group, P = 0.011). Logistic regression analysis revealed high BMI was independently associated with decreased incidence of chylothorax [HR 0.86; 95 % confidence interval 0.76-0.97]. Overweight and obese patients had significantly better overall survival than underweight patients (median OS 55.6 vs. 32.5 months, P = 0.013), while the pathological stage was significantly higher in underweight patients (P = 0.001). In multivariate analysis, T status, N status, differentiation grade, and tumor length were identified as independent prognostic factors.

CONCLUSION

A high BMI is not associated with increased overall morbidity following esophagectomy; moreover, it is associated with decreased incidence of chylothorax. The better overall survival in patients with high BMI compared with those with low BMI might be due to a relatively low pathological stage. A high BMI should therefore not be a relative contraindication for esophagectomy.

Prognostic significance of the pN classification supplemented by body mass index for esophageal squamous cell carcinoma

Background

Body mass index (BMI) has been associated with the risk of esophageal cancer. But the influence of BMI on postoperative complications and prognosis has always been controversial.

Methods

Between 2000 and 2007, 424 patients with esophageal squamous cell carcinoma (ESCC) underwent R0 esophagectomy at our center without neoadjuvant therapy. We performed univariate and multivariate analyses to identify prognostic factors for survival.

Results

Patients were divided into three groups according to Asian-specific BMI cut-off value: underweight (n = 45), normal weight (n = 228), and overweight and obese (n = 151). Mean follow-up time was 39 months. The five-year overall survival (OS) rate was 19%, 34%, and 42% for underweight, normal weight, and overweight and obese, respectively (P < 0.001). The five-year disease-free survival (DFS) rate was 24%, 41%, and 74% for underweight, normal weight, and overweight and obese, respectively (P < 0.001). Multivariate analysis showed that pT, pN, and BMI were independent prognostic factors for DFS and OS. The C-index to the combined model showed improved predictive ability when compared to the pN classification (0.779 vs. 0.734).

Conclusion

Preoperative BMI was an independent prognostic factor for OS and DFS. The proposed new prognostic model with the pN classification supplemented by BMI might improve the ability to discriminate ESCC patients’ outcome.

Diabetes and risk of anastomotic leakage after gastrointestinal surgery

BACKGROUND

Anastomotic leakage (AL) is one of the most common and lethal complications in gastrointestinal surgery. However, the relationship between AL risk and diabetes mellitus (DM) remains ambiguous. This meta-analysis was to evaluate the association between DM and AL risk in patients after gastrointestinal resection.

METHODS

Odds ratios (OR) estimate with their corresponding 95% confidence intervals (CIs) were combined and weighted to produce pooled OR using the fixed-effects model. Relative risks were calculated in subgroup analysis of prospective studies. We calculated publication bias by Begg rank correlation test and Egger linear regression test.

RESULTS

DM was significantly and independently associated with an increased risk of AL morbidity in colorectal patients, 1.661 times in total patients (95% CIs = 1.266-2.178), 1.995 times in a subgroup of case-control studies, 1.581 times in cohort investigations, 1.688 times in retrospective trials, and 1.562 times in prospective designs. After adjusting for the factor of obesity and/or body mass index in the subgroup analyses of colorectal surgery, DM patients without obesity experienced a significantly increased risk of AL (OR = 1.572, 95% CIs = 1.112-2.222). Furthermore, when obesity had not been adjusted, DM patients endured a dramatical increase of AL incidence (OR = 1.812, 95% CIs = 1.171-2.804). Perforation incidence after gastric resection showed borderline association with DM (OR = 2.170, 95% CIs = 0.956-4.926).

CONCLUSIONS

The present meta-analysis provides strong evidence for the first time that DM is significantly and independently associated with an increased risk of AL mortality in colorectal surgery.

Impact of body mass index on surgical outcomes after esophagectomy for patients with esophageal squamous cell carcinoma

BACKGROUND

Patients with overweight reportedly have more comorbidities, including diabetes mellitus and cardiovascular disease, and longer operating times as well as more blood loss during surgery compared with those with normal weight. However, the impact of overweight on the short-term outcome after transthoracic esophagectomy for patients with esophageal squamous cell carcinoma (ESCC) remains unclear. We hypothesized that overweight has a negative impact on short-term surgical outcomes after esophagectomy for patients with ESCC.

METHODS

A total of 304 patients who underwent transthoracic esophagectomy for ESCC were included in this study. Body mass index (BMI) was classified into three categories, <18.49, 18.50-24.99, and >25.00 (kg/m(2)), defined as low, normal, and high BMI, respectively, according to the World Health Organization criteria. We investigated the association of BMI status with patient demographics and surgical outcomes after esophagectomy for patients with ESCC. In addition, overall survival and relapse-free survival stratified by BMI were compared.

RESULTS

Fifty-nine (19.4 %) and 41 (13.4 %) patients were classified to low BMI and high BMI, respectively. The high-BMI group had significantly higher comorbidity rates of diabetes mellitus (p < 0.01) and anastomotic leakage (p = 0.011) than the normal-BMI group. There were no significant association between high BMI and another various complications except for an anastomotic leakage, severe complications defined by Clavien-Dindo classification and in-hospital mortality. In multivariate analysis, high BMI was a significant risk factor for anastomotic leakage (p = 0.030, hazard ratio; 3.423, 95%CI; 1.128-10.38). On the other hand, no significant association was observed between low BMI and short surgical outcomes. There were no significant differences in overall and relapse-free survival among the three BMI groups in univariate and multivariate analysis (p = 0.128 and p = 0.584, respectively).

CONCLUSION

The surgical treatment should not be denied for patients with ESCC due to overweight and underweight. However, intraoperative prevention and postoperative careful monitoring for anastomotic leakage might be required after esophagectomy for overweight patients with ESCC.

Obesity was associated with a decreased postoperative recurrence of rectal cancer in a Japanese population

PURPOSE

Obesity contributes to the technical difficulty of rectal surgery and is considered to be a risk factor for postoperative complications. The impact of obesity on the long-term outcomes of rectal cancer surgery remains unclear.

METHODS

A total of 263 consecutive rectal cancer patients who underwent surgery were categorized into two groups according to the body mass index (BMI) based on the Asian BMI classification: non-obese (BMI <25 kg/m(2)) and obese (BMI ≥25 kg/m(2)). The postoperative survival and recurrence rates and oncological surgical quality indicators were compared between groups using the univariate and multivariate analyses. The differences in recurrence patterns were assessed by a competing risk regression analysis.

RESULTS

64 (24%) patients were included in the obese group. The number of retrieved lymph nodes was significantly greater in the non-obese group than in the obese group (22.4 vs. 16.0, P < 0.01). The 5-year disease-free survival (DFS) rates were 86.5 and 68.8% in the obese and non-obese groups, respectively (P = 0.01). The multivariate analysis demonstrated that obesity significantly decreased the postoperative recurrence rate (P = 0.04). Moreover, the BMI was significantly associated with distant metastasis (P = 0.04).

CONCLUSIONS

Obese rectal cancer patients have high DFS rates and a decreased incidence of distant metastases compared to non-obese patients. The BMI may be a key factor for predicting the postoperative prognosis and determination of an appropriate strategy for the treatment of rectal cancer patients.

Update on clinical impact, documentation, and management of complications associated with esophagectomy

The assessment and monitoring of complications associated with esophageal resection suffers from the absence of an internationally recognized system for documenting the incidence and severity of complications. The impact of complications is significant, with direct effects being identified on mortality, length of stay, postoperative quality of life, and long-term survival. Newer systems of assessing surgical complication severity and the resources required to treat complications include the Accordion and Clavien grading systems. New endoscopic and interventional approaches to treating anastomotic leak and stricture and chyle leak can selectively decrease length of stay and costs of managing complications.

The impact of body mass index on complication and survival in resected oesophageal cancer: a clinical-based cohort and meta-analysis

Background:

Body mass index (BMI) has been associated with the risk of oesophageal cancer. But the influence of BMI on postoperative complication and prognosis has always been controversial.

Methods:

In total, 2031 consecutive patients who underwent oesophagectomy between 1998 and 2008 were classified according to Asian-specific BMI (kg m⁻²) cutoff values. The impact of BMI on overall survival (OS) was estimated using the Kaplan–Meier method and Cox proportional hazard models. We performed a meta-analysis to examine the association of BMI with OS and postoperative complication.

Results:

Patients with higher BMI had more postoperative complication (P=0.002), such as anastomotic leakage (P=0.016) and cardiovascular diseases (P<0.001), but less incidence of chylous leakage (P=0.010). Logistic regression analysis showed that BMI (P=0.005) was a confounding factor associated with postoperative complication. Multivariate analysis showed that overweight and obese patients had a more favourable survival than normal weight patients (HR (hazard ratio) = 0.80, 95% CI (confidence interval): 0.70–0.92, P=0.001). Subgroup analysis showed that the association with higher BMI and increased OS was observed in patients with oesophageal squamous cell carcinoma (ESCC) (P<0.001), oesophageal adenocarcinoma (EA) (P=0.034), never-smoking (P=0.035), ever-smoking (P=0.035), never alcohol consumption (P=0.005), weight loss (P=0.003) and advanced pathological stage (P<0.001). The meta-analysis further corroborated that higher BMI was associated with increased complication of anastomotic leakage (RR (risk ratio)=1.04, 95% CI: 1.02–1.06, P=0.001), wound infection (RR=1.03, 95% CI: 1.00–1.05, P=0.031) and cardiovascular diseases (RR=1.02, 95% CI: 1.00–1.05, P=0.039), but decreased incidence of chylous leakage (RR=0.98, 95% CI: 0.96–0.99, P<0.001). In addition, high BMI could significantly improved OS (HR=0.78, 95% CI: 0.71–0.85, P<0.001).

Conclusion:

Preoperative BMI was an independent prognostic factor for survival, and strongly associated with postoperative complications in oesophageal cancer.