Systematic review of prognostic roles of body mass index for patients undergoing lung cancer surgery: does the 'obesity paradox' really exist?

Association between body mass index and lymph node metastasis among women with cervical cancer: a systematic review and network meta-analysis

PURPOSE

Lymph node status is a determinant of survival in patients with early-stage cervical cancer. However, the relationship between obesity and lymph node status remains unclear. Therefore, this systematic review aims to evaluate the correlation between body mass index (BMI) and lymph node metastasis in cervical cancer.

METHODS

Cohort studies through six databases were reviewed until December 2021. Odds ratios (ORs) for lymphatic metastasis were estimated using random-effects models and network meta-analysis. BMI groups for lymph node metastasis were ranked. Heterogeneities were assessed using I2. Subgroup analyses were performed to determine possible sources of heterogeneity.

RESULTS

No significant difference was found between obese (BMI ≥ 25) and non-obese patients (BMI < 25) (OR = 1.01; 95% CI 0.69-1.47; P = 0.97). In subgroup analyses, obesity was associated with higher risk among the Americans and advanced-stage patients. The grouping analysis based on BMI and the rankogram values revealed that the '35 ≤ BMI' group had the highest risk of lymph node metastasis.

CONCLUSION

Although there were no significant differences in lymph node metastasis between obese and non-obese cervical cancer patients in overall analysis, patients with BMI ≥ 35 were at significantly higher risk of lymph node metastasis.

Association between insulin resistance, metabolic syndrome and its components and lung cancer: a systematic review and meta-analysis

BACKGROUND

A growing body of evidence points to the association between insulin resistance (IR), metabolic syndrome (MetS) and its components and lung cancer incidence, but remains controversial and unknown.

METHODS

A systematic search was conducted through PubMed, Embase, Cochrane Library, the China National Knowledge Infrastructure (CNKI) and Wanfang databases for the corresponding studies. Each study reported the risk estimate and 95% confidence intervals (CI) for lung cancer, and a fixed effects model or random effects model was used for outcome.

RESULTS

We included 31 publications involving 6,589,383 people with 62,246 cases of lung cancer. Diabetes mellitus (DM) (RR = 1.11, 95% CI  1.06-1.16, P = 0.000) and IR (RR = 2.35, 95% CI  1.55-3.58, P = 0.000) showed a positive association with lung cancer risk. BMI (RR = 0.66, 95% CI  0.54-0.81, P = 0.000) and HDL-C (RR = 0.88, 95% CI  0.79-0.97, P = 0.010) were negatively correlated with lung cancer. MetS(RR = 0.99, 95% CI  0.90-1.09, P = 0.801), TC (RR = 0.93, 95% CI  0.81-1.06, P = 0.274), TG (RR = 0.99, 95% CI  0.88-1.12,P = 0.884), LDL-C (RR = 1.01, 95% CI  0.87-1.16, P = 0.928), hypertension (RR = 1.01, 95% CI  0.88-1.15, P = 0.928), FBG (RR = 1.02, 95% CI  0.92-1.13, P = 0.677) and obesity (RR = 1.11, 95% CI  0.92-1.35, P = 0.280) were not associated with lung cancer.

CONCLUSION

Our study showed that the risk of lung cancer is correlated with DM, IR, BMI, and HDL-C. Timely control of these metabolic disorders may have a positive effect on preventing lung cancer. Trial registration Our study has been registered in the Prospective Register of Systematic Reviews (PROSPERO), ID: CRD42023390710.

Lung cancer, comorbidities, and medication: the infernal trio

Most patients with lung cancer are smokers and are of advanced age. They are therefore at high risk of having age- and lifestyle-related comorbidities. These comorbidities are subject to treatment or even polypharmacy. There is growing evidence of a link between lung cancer, comorbidities and medications. The relationships between these entities are complex. The presence of comorbidities and their treatments influence the time of cancer diagnosis, as well as the diagnostic and treatment strategy. On the other hand, cancer treatment may have an impact on the patient's comorbidities such as renal failure, pneumonitis or endocrinopathies. This review highlights how some comorbidities may have an impact on lung cancer presentation and may require treatment adjustments. Reciprocal influences between the treatment of comorbidities and anticancer therapy will also be discussed.

Nomogram for predicting postoperative pulmonary complications in spinal tumor patients

OBJECTIVES

Although several independent risk factors for postoperative pulmonary complications (PPCs) after spinal tumor surgery have been studied, a simple and valid predictive model for PPC occurrence after spinal tumor surgery has not been developed.

PATIENTS AND METHODS

We collected data from patients who underwent elective spine surgery for a spinal tumor between 2013 and 2020 at a tertiary hospital in China. Data on patient characteristics, comorbidities, preoperative examinations, intraoperative variables, and clinical outcomes were collected. We used univariable and multivariable logistic regression models to assess predictors of PPCs and developed and validated a nomogram for PPCs. We evaluated the performance of the nomogram using the area under the receiver operating characteristic curve (ROC), calibration curves, the Brier Score, and the Hosmer-Lemeshow (H-L) goodness-of-fit test. For clinical use, decision curve analysis (DCA) was conducted to identify the model's performance as a tool for supporting decision-making.

RESULTS

Among the participants, 61 (12.4%) individuals developed PPCs. Clinically significant variables associated with PPCs after spinal tumor surgery included BMI, tumor location, blood transfusion, and the amount of blood lost. The nomogram incorporating these factors showed a concordance index (C-index) of 0.755 (95% CI: 0.688-0.822). On internal validation, bootstrapping with 1000 resamples yielded a bias-corrected area under the receiver operating characteristic curve of 0.733, indicating the satisfactory performance of the nomogram in predicting PPCs. The calibration curve demonstrated accurate predictions of observed values. The decision curve analysis (DCA) indicated a positive net benefit for the nomogram across most predicted threshold probabilities.

CONCLUSIONS

We have developed a new nomogram for predicting PPCs in patients who undergo spinal tumor surgery.

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

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

The effect of perioperative immunonutritional support on nutritional and inflammatory status in patients undergoing lung cancer surgery: a prospective, randomized controlled study

PURPOSE

Nutritional status is affected in patients who undergo lung cancer surgery (LCS). This study is aimed at investigating the effects of the use of immunonutritional support in the perioperative period on nutritional and inflammatory status in patients undergoing LCS.

METHODS

A single-center, prospective, randomized controlled clinical trial was conducted with seventy patients planning to have LCS and randomized into treatment (TG) and control groups (CG). Immunonutritional support was given orally twice a day for ten days before the operation and five days after the operation in the treatment group. The nutritional status of the patients was screened with the Patient-Generated Subjective Global Assessment (PG-SGA); the Prognostic Nutrition Index (PNI) and the Systemic Inflammation Index (SII) were calculated. The physical activity status was assessed with the Eastern Cooperative Oncology Group Performance Status (ECOG-PS).

RESULTS

Post-op nutritional status of the TG patients was better than the CG group (p = 0.009). Post-operative PG-SGA score was higher than preoperative PG-SGA score in both groups (p < 0.001). In the post-operative period, nutritional status (in terms of PG-SGA score category) in the patients in the TG was better than the CG (p = 0.046). In both groups, post-op ECOG score was higher than the pre-op ECOG score (p < 0.001). Post-op physical performance status was found to be better in the TG compared to the CG (p = 0.001). PNI level decreased statistically and significantly in the post-op period compared to the pre-op period, SII levels increased.

CONCLUSION

Patients who will undergo LCS should be supported in terms of immunonutrition starting from the preoperative period.

Two-sided roles of adipose tissue: Rethinking the obesity paradox in various human diseases from a new perspective

Overweight and obesity, as a result of excess fat accumulation, have become a worldwide public health issue. Recent studies have shown that obesity is closely related to many human diseases, such as cancer, cardiovascular diseases, and type 2 diabetes mellitus, in which adipose tissue plays a dual role. In addition to thermal and mechanical insulation and a critical role in energy storage and heat production, adipose tissue is also a highly plastic endocrine and signaling organ that secretes multiple bioactive molecules for inter-organ crosstalk. The phenotypic and biological changes of adipose tissue under pathological conditions, especially in obesity, increase the challenge of deciphering the positive or negative effects of adipose tissue in disease. Despite numerous studies on obesity and adipose tissue, the ambiguous role of adipose tissue on specific organs or tissues in different diseases is not fully understood, and the definite mechanisms remain obscure. In this review, we first summarize the basic biological characteristics of adipose tissue in the physiological state and the abnormal remodeling of adipose tissue during obesity. We then discuss the complex and disparate effects of obesity on various human diseases, with a particular focus on the dual roles and underlying mechanisms of adipose tissue, a quintessential player in obesity, in this process. More importantly, rethinking the causes of the "obesity paradox" phenomenon in diseases from the perspective of adipose homeostasis and dysfunction provides a novel strategy for disease treatment by intervening in fat function.

Role of adipocytokines in endometrial cancer progression

Endometrial cancer is considered a significant barrier to increasing life expectancy and remains one of the most common malignant cancers among women in many countries worldwide. The increasing mortality rates are potentially proportional to the increasing obesity incidence. Adipose tissue secretes numerous adipocytokines, which may play important roles in endometrial cancer progression. In this scenario, we describe the role of adipocytokines in cell proliferation, cell invasion, cell adhesion, inflammation, angiogenesis, and anti-apoptotic action. A better understanding of the mechanisms of these adipocytokines may open up new therapeutic avenues for women with endometrial cancer. In the future, larger prospective studies focusing on adipocytokines and specific inhibitors should be directed at preventing the rapidly increasing prevalence of gynecological malignancies.

Preoperative High Visceral Fat Increases Severe Complications but Improves Long-Term Prognosis after Gastrectomy for Patients with Advanced Gastric Cancer: A Propensity Score Matching Analysis

This study investigated the paradox of high visceral fat mass increasing severe complications but improving long-term prognosis after radical gastrectomy for gastric cancer. This was a retrospective cohort study of consecutive patients with primary stage I–III gastric cancer who underwent gastrectomy between April 2008 and June 2018. The visceral adipose tissue index (VAI) was calculated by dividing the visceral fat mass preoperatively measured on computed tomography by the square of the height. Patients with VAIs below the median cut-off value were classified as low-VAI, while those above it were classified as high-VAI. We compared the postoperative complication rate and overall survival (OS) in the low- and high-VAI groups after adjusting patient characteristics using propensity score matching (PSM). There were 155 patients in both groups after PSM. After matching, there was no significant difference in factors other than BMI and VAI that were not adjusted. The high-VAI group had more severe postoperative complications (p = 0.018), but the OS was significantly better in the high-VAI group (hazard ratio 0.611, 95%CI 0.403–0.928, p = 0.021). Preoperative high visceral fat mass not only increased severe complications, but also improved OS after gastrectomy in patients with advanced gastric cancer.

Visceral Obesity in Non-Small Cell Lung Cancer

While obesity measured by body mass index (BMI) has been paradoxically associated with reduced risk and better outcome for lung cancer, recent studies suggest that the harm of obesity becomes apparent when measured as visceral adiposity. However, the prevalence of visceral obesity and its associations with demographic and tumor features are not established. We therefore conducted an observational study of visceral obesity in 994 non-small cell lung cancer (NSCLC) patients treated during 2008-2020 at our institution. Routine computerized tomography (CT) images of the patients, obtained within a year of tumor resection or biopsy, were used to measure cross-sectional abdominal fat areas. Important aspects of the measurement approach such as inter-observer variability and time stability were examined. Visceral obesity was semi-quantified as visceral fat index (VFI), the fraction of fat area that was visceral. VFI was found to be higher in males compared to females, and in former compared to current or never smokers. There was no association of VFI with tumor histology or stage. A gene expression-based measure of tumor immunogenicity was negatively associated with VFI but had no bearing with BMI. Visceral obesity is appraisable in routine CT and can be an important correlate in lung cancer studies.

Is Age-Predicted Maximal Heart Rate Applicable in Patients With Heart or Lung Disease?

Objective

To compare the predicted and actual maximal heart rate (HRmax) values in the cardiopulmonary exercise test (CPET).

Methods

We retrospectively investigated 1,060 patients who underwent a CPET between January 2016 and April 2020 at our institution’s cardiopulmonary rehabilitation center. The following patients were included: those aged >20 years, those tested with a treadmill, and those who underwent symptom-limited maximum exercise testing— reaching ≥85% of the predicted HRmax (62% if taking beta-blockers) and highest respiratory exchange ratio ≥1.1. Ultimately, 827 patients were included in this study. Data on diagnosis, history of taking beta-blockers, age, body mass index (BMI), and CPET parameters were collected. Subgroup analysis was performed according to age, betablockers, BMI (low <18.5 kg/m², normal, and high ≥25 kg/m²), and risk classification.

Results

There was a significant difference between the actual HRmax and the predicted value (p<0.001). Betablocker administration resulted in a significant difference in the actual HRmax (p<0.001). There were significant differences in the moderate-to-high-risk and low-risk groups and the normal BMI and high BMI groups (p<0.001). There was no significant difference between the elderly and younger groups. We suggest new formulae for HRmax of cardiopulmonary patients: estimated HRmax=183-0.76×age (the beta-blocker group) and etimated HRmax=210-0.91×age (the non-beta-blocker group).

Conclusion

Age-predicted HRmax was significantly different from the actual HRmax of patients with cardiopulmonary disease, especially in the beta-blocker group. For participants with high BMI and moderate-tosevere risk, the actual HRmax was significantly lower than the predicted HRmax.

Mortality risk in patients with underweight or obesity with peripheral artery disease: a meta-analysis including 5,735,578 individuals

OBJECTIVES

The "obesity paradox" - in which patients with obesity exhibit superior survival than normal-weight counterparts - has been reported for several diseases. However, obesity is a well-known risk factor for cardiovascular disease, and whether the obesity paradox is present in peripheral artery disease (PAD) is unknown.

METHODS

A comprehensive search for studies that reported mortality in patients with PAD grouped by BMI identified 12 studies. We compared the survival of underweight patients with those who were not underweight, and patients with obesity against those without. Underweight was defined by a BMI value of <18.5 kg/m² in most studies and obesity by BMI ≥ 30 kg/m². Subgroup analyses were performed according to length of follow-up, presentation of PAD, and mode of revascularization. Meta-regression analyses were conducted, with covariates including age, sex, presence of coronary artery disease (CAD) and diabetes mellitus (DM).

RESULTS

The mortality risk of underweight patients with PAD was significantly higher compared to those who are not underweight (HR 1.72, 95% CI 1.38-2.14; I² = 84.2%). In contrast, the mortality risk of patients with obesity with PAD was significantly lower than those without (HR 0.78, 95% CI 0.62-0.97; I² = 89.8%). These findings remained consistent regardless of the presentation of PAD, revascularization, age, sex, or presence of CAD. The risk of death in the short-term of underweight patients (HR 1.50, 95% CI 0.47-4.72) and patients with obesity (HR 0.86, 95% CI 0.66-1.13) were not significantly different from their counterparts. The meta-regression showed that of the association between obesity and better survival was more pronounced in studies with a greater proportion of patients with concomitant CAD (regression coefficient -0.029, 95% CI -0.054 to -0.004).

CONCLUSIONS

In patients with PAD, mortality is higher among underweight patients and lower among patients with obesity. The mechanisms underlying the obesity paradox in patients with PAD remain to be elucidated, and further evidence is required to guide optimal weight control strategies in these patients.

Obesity Does Not Increase Perioperative Outcomes in Older Patients Undergoing Thoracoscopic Anatomic Lung Cancer Surgery

Objectives

To investigate the relationship between obesity status and perioperative outcomes in elderly patients undergoing thoracoscopic anatomic lung cancer surgery.

Methods

From January 2016 to December 2018, we performed a monocentric retrospective cohort study among 4164 consecutive patients aged 65 years or older who underwent thoracoscopic anatomic lung cancer surgery at Shanghai Chest Hospital. Two groups were stratified by body mass index (BMI): nonobese (BMI<28kg/m²) and obese status (BMI≥28kg/m²). Using a 1:1 propensity score matching (PSM) analysis to compare perioperative outcomes between two groups.

Results

4035 older patients were eventually enrolled, with a mean age of 69.8 years (range: 65-87), and 305 patients were eligible for obese status, with a mean BMI of 29.8 ± 1.7kg/m². Compared with nonobese patients, obese patients were more likely to have higher rates of intraoperative hypoxemia (1.2% vs 3.9%, P=0.001) and new-onset arrhythmia (2.3% vs 4.3%, P=0.034). The difference in intraoperative transfusion and conversion rates and postoperative outcomes regarding pulmonary complications, new-onset arrhythmia, transfusion, length of hospital stay, 30-day readmission and hospitalization costs between two groups were not significant (P>0.05). After a 1:1 PSM analysis, the difference in both intraoperative and postoperative complications among two groups were not significant (P>0.05). In subgroup analysis, patients with BMI≥30kg/m² had a similar incidence of perioperative complications compared to patients with BMI between 28 and 30 kg/m² (P>0.05).

Conclusions

Our research data support evidence for “obesity paradox” and also contribute the growing body of evidence that obesity in older patients should not exclude candidates for thoracoscopic anatomic lung cancer surgery.

Obesity is associated with improved postoperative overall survival, independent of skeletal muscle mass in lung adenocarcinoma

BACKGROUND

Although the obesity paradox is a topic of immense interest for oncologists and epidemiologists, the mechanism underlying this unexpected benefit of obesity is poorly understood. We explored the prognostic value of obesity and its association with skeletal muscle mass.

METHODS

This retrospective study evaluated the data of patients who underwent surgical excision for lung adenocarcinoma between January 2011 and December 2015. Body mass index was categorized according to the criteria of the Asia-Pacific classification. Cross-sectional areas of the skeletal muscle, subcutaneous fat, and visceral fat were measured. Skeletal muscle mass status was defined based on the cut-offs of skeletal muscle index (cm² /m² ), calculated as the area of skeletal muscle divided by height squared. Overall survival was estimated using the Kaplan-Meier method, and differences in survival probabilities were compared using the log-rank test. Cox proportional hazards regression analysis was conducted to determine the association with overall survival.

RESULTS

A total of 636 patients with a median age of 61 years (interquartile range, 54.0-68.5 years; 321 men and 315 women) were included. Obese patients (body mass index ≥ 25 kg/m² ) had longer overall survival than non-obese patients (mean, 110.2 months vs. 98.7 months; log-rank P = 0.015). Under multivariable Cox proportional hazard regression analysis, obesity was associated with longer overall survival after adjusting for covariates (hazard ratio, 0.59; 95% confidence interval, 0.40-0.86; P = 0.007). The prognostic value of obesity remained and predicted favourable overall survival after additional adjusting for skeletal muscle mass status (hazard ratio, 0.57; 95% confidence interval, 0.36-0.89; P = 0.014), skeletal muscle index (hazard ratio, 0.53; 95% confidence interval, 0.33-0.84; P = 0.008), or skeletal muscle area (hazard ratio, 0.61; 95% confidence interval, 0.38-0.98; P = 0.041). No association was observed between skeletal muscle mass status and the impact of body mass index on overall survival (P for interaction = 0.512).

CONCLUSIONS

Obesity was associated with favourable overall survival, independent of skeletal muscle mass, after surgical excision of lung adenocarcinoma.

Exploring the Impact of the Obesity Paradox on Lung Cancer and Other Malignancies

Simple Summary

Studies have shown that obesity is associated with many adverse health effects, including worse cancer outcomes. Many studies paradoxically suggest a survival benefit for obesity in treatment outcomes of cancers such as non-small-cell lung cancer. This relationship is not seen in animal models. We hypothesize that this relationship is secondary to suboptimal quantification of adiposity, enhanced immunotherapy response, and variables such as sex, medications, and smoking status. There are many ways to measure and classify adiposity, but the ability to distinguish abdominal obesity is likely key in predicting accurate prognosis. There are many ways obesity impacts cancer treatment course from diagnosis to survivorship. In this paper, we aim to analyze the factors contributing to the obesity paradox and its effect on lung cancer. This can aid the treatment and prognosis of lung cancer and may support further research into obesity-specific impacts on this malignancy.

Abstract

There is a paradoxical relationship between obesity, as measured by BMI, and many types of cancer, including non-small-cell lung cancer. Obese non-small-cell lung cancer patients have been shown to fare better than their non-obese counterparts. To analyze the multifaceted effects of obesity on oncologic outcomes, we reviewed the literature on the obesity paradox, methods to measure adiposity, the obesity-related derangements in immunology and metabolism, and the oncologic impact of confounding variables such as gender, smoking, and concomitant medications such as statins and metformin. We analyzed how these aspects may contribute to the obesity paradox and cancer outcomes with a focus on lung cancer. We concluded that the use of BMI to measure adiposity is limited and should be replaced by a method that can differentiate abdominal obesity. We also concluded that the concomitant metabolic and immunologic derangements caused by obesity contribute to the obesity paradox. Medications, gender, and smoking are additional variables that impact oncologic outcomes, and further research needs to be performed to solidify the mechanisms.

The ambiguous role of obesity in oncology by promoting cancer but boosting antitumor immunotherapy

Obesity is nowadays considered a pandemic which prevalence's has been steadily increasingly in western countries. It is a dynamic, complex, and multifactorial disease which propitiates the development of several metabolic and cardiovascular diseases, as well as cancer. Excessive adipose tissue has been causally related to cancer progression and is a preventable risk factor for overall and cancer-specific survival, associated with poor prognosis in cancer patients. The onset of obesity features a state of chronic low-grade inflammation and secretion of a diversity of adipocyte-derived molecules (adipokines, cytokines, hormones), responsible for altering the metabolic, inflammatory, and immune landscape. The crosstalk between adipocytes and tumor cells fuels the tumor microenvironment with pro-inflammatory factors, promoting tissue injury, mutagenesis, invasion, and metastasis. Although classically established as a risk factor for cancer and treatment toxicity, recent evidence suggests mild obesity is related to better outcomes, with obese cancer patients showing better responses to treatment when compared to lean cancer patients. This phenomenon is termed obesity paradox and has been reported in different types and stages of cancer. The mechanisms underlying this paradoxical relationship between obesity and cancer are still not fully described but point to systemic alterations in metabolic fitness and modulation of the tumor microenvironment by obesity-associated molecules. Obesity impacts the response to cancer treatments, such as chemotherapy and immunotherapy, and has been reported as having a positive association with immune checkpoint therapy. In this review, we discuss obesity's association to inflammation and cancer, also highlighting potential physiological and biological mechanisms underlying this association, hoping to clarify the existence and impact of obesity paradox in cancer development and treatment.

Twenty-Year Survival of Patients Operated on for Non-Small-Cell Lung Cancer: The Impact of Tumor Stage and Patient-Related Parameters

Surgery is the mainstay treatment of non-small-cell lung cancer (NSCLC), but its impact on very-long-term survival (beyond 15 years) has never been evaluated.

METHODS

All patients operated on for major lung resection (Jun. 2001-Dec. 2002) for NSCL in the Thoracic Surgery Department at Paris-Hôtel-Dieu-University-Hospital were included. Patients' characteristics were prospectively collected. Vital status was obtained by checking INSEE database and verifying if reported as "non-death" by the hospital administrative database and direct phone interviews with patients of families.

RESULTS

345 patients were included. The 15- and 20-year survival rates were 12.2% and 5.7%, respectively. At univariate analysis, predictors of worse survivals were: increasing age at surgery (p = 0.0042), lower BMI (p = 0.009), weight loss (p = 0.0034), higher CRP (p = 0.049), pathological stage (p = 0.00000042), and, among patients with adenocarcinoma, higher grade (p = 0.028). Increasing age (p = 0.004), cumulative smoking (p = 0.045), lower BMI (0.046) and pathological stage (p = 0.0026), were independent predictors of long-term survival at Cox multivariate analysis. In another model, increasing age (p = 0.013), lower BMI (p = 0.02), chronic bronchitis (p = 0.03), lower FEV1% (p = 0.00019), higher GOLD class of COPD (p = 0.0079), and pathological stage (p = 0.000024), were identified as independent risk factors.

CONCLUSIONS

Very-long-term survivals could be achieved after surgery of NSCLC, and factors classically predicting 5- and 10-years survival also determined longer outcomes suggesting that both initial tumor aggressiveness and host's characteristics act beyond the period usually taken into account in oncology.

Short-term Mortality and Postoperative Complications of Abdominal Aortic Aneurysm Repair in Obese versus Non-obese Patients

Background

Obesity is a risk factor not only for abdominal aortic aneurysm (AAA) but also for complications after vascular surgery. This study was to determine the effect of obesity on short-term mortality and post-intervention complications after AAA repair.

Methods

A systematic review and meta-analysis were performed. A systematic search was performed in PubMed; the articles describing the differences in post-intervention complications after open or endovascular repair of an AAA between obese and non-obese patients were selected. The primary outcome was short-term mortality defined as in-hospital mortality or mortality within 30 days after AAA repair. The secondary outcomes were cardiac complications, pulmonary failure, renal failure, and wound infections. The meta-analysis was performed using OpenMeta.

Results

Four articles were included in the meta-analysis; these articles included 35,989 patients of which 10,917 (30.3%) were obese. The meta-analysis showed no significant differences for short-term mortality (odds ratio [OR], 0.85; 95% confidence interval [CI], 0.69-1.04). Also, no significant difference was found in pulmonary failure (OR, 1.09; 95% CI, 0.85-1.42). However, obese patients were less likely to suffer from cardiac complications (OR, 0.73; 95% CI, 0.55-0.96). Nevertheless, there was a significantly higher risk of renal failure (OR, 1.16; 95% CI, 1.05-1.30) and wound infections (OR, 1.92; 95% CI, 1.55-2.38) in obese patients.

Conclusion

Obesity is not a risk factor for short-term mortality after AAA repair compared to non-obesity. Moreover, obese patients suffer less from cardiac complications than non-obese patients.

A Novel Nomogram for Early Identification and Intervention in Colorectal Cancer Patients at Risk for Malnutrition

BACKGROUND

Malnutrition is under-recognized in cancer patients and can lead to poor treatment outcomes. We aim to develop an outpatient-focused score based on the Malnutrition Screening Tool (MST) to help identify colorectal cancer (CRC) profiles at high risk for malnutrition.

METHODS

506 CRC patients during initial outpatient oncology consultation at our tertiary referral outpatient oncology clinic completed the MST. Objective and subjective data were collected through chart review. Data gathered are as follows: demographics, anthropometrics, laboratory values, patient-reported symptoms, MST score, cancer history, performance status, socioeconomic status, and Charlson Comorbidity. Predictors of malnutrition were identified by logistic regression. Receiver operating curve (ROC), area under the curve (AUC), and our model's predictability were determined.

RESULTS

Significant predictors of malnutrition are as follows: younger age (20-39 vs >40 years) (P = .007), normal-to-low body mass index at presentation (P = .019), Eastern Cooperative Oncology Group classification 2-3 (P = .012), metastatic disease (P = .046), albumin <3.0 g/dL (P = .033), fatigue (P < .001), and change in stool/bowel habits (P = .002). In our derived malnutrition score, risk of malnutrition increased from 11% for score 0, to 100% for scores 9-10. Receiver operating curve showed AUC .745 (95% CI, .697-.793).

DISCUSSION

An outpatient clinic-derived malnutrition score obtained from objective and patient-reported variables may facilitate identification of CRC patients at highest risk for malnutrition. Rapid identification and intervention in high-risk patients may improve treatment recovery, therapy tolerance, and quality of life. Our tool requires external validation before application in clinical practice.

Association of Obesity With Survival Outcomes in Patients With Cancer: A Systematic Review and Meta-analysis

Importance

Obesity, defined as a body mass index (BMI) greater than 30, is associated with a significant increase in the risk of many cancers and in overall mortality. However, various studies have suggested that patients with cancer and no obesity (ie, BMI 20-25) have worse outcomes than patients with obesity.

Objective

To assess the association between obesity and outcomes after a diagnosis of cancer.

Data Sources

PubMed, the Cochrane Library, and EMBASE were searched from inception to January 2020.

Study Selection

Studies reporting prognosis of patients with obesity using standard BMI categories and cancer were included. Studies that used nonstandard BMI categories, that were limited to children, or that were limited to patients with hematological malignant neoplasms were excluded. Screening was performed independently by multiple reviewers. Among 1892 retrieved studies, 203 (17%) met inclusion criteria for initial evaluation.

Data Extraction and Synthesis

The Meta-analysis of Observational Studies in Epidemiology (MOOSE) and Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines were reporting guideline was followed. Data were extracted by multiple independent reviewers. Risk of death, cancer-specific mortality, and recurrence were pooled to provide an adjusted hazard ratio (HR) with a 95% CI . A random-effects model was used for the retrospective nature of studies.

Main Outcomes and Measures

The primary outcome of the study was overall survival (OS) in patients with cancer, with and without obesity. Secondary end points were cancer-specific survival (CSS) and progression-free survival (PFS) or disease-free survival (DFS). The risk of events was reported as HRs with 95% CIs, with an HR greater than 1 associated with a worse outcome among patients with obesity vs those without.

Results

A total of 203 studies with 6 320 365 participants evaluated the association of OS, CSS, and/or PFS or DFS with obesity in patients with cancer. Overall, obesity was associated with a reduced OS (HR, 1.14; 95% CI, 1.09-1.19; P < .001) and CSS (HR, 1.17; 95% CI, 1.12-1.23; P < .001). Patients were also at increased risk of recurrence (HR, 1.13; 95% CI, 1.07-1.19; P < .001). Conversely, patients with obesity and lung cancer, renal cell carcinoma, or melanoma had better survival outcomes compared with patients without obesity and the same cancer (lung: HR, 0.86; 95% CI, 0.76-0.98; P = .02; renal cell: HR, 0.74; 95% CI, 0.53-0.89; P = .02; melanoma: HR, 0.74; 95% CI, 0.57-0.96; P < .001).

Conclusions and Relevance

In this study, obesity was associated with greater mortality overall in patients with cancer. However, patients with obesity and lung cancer, renal cell carcinoma, and melanoma had a lower risk of death than patients with the same cancers without obesity. Weight-reducing strategies may represent effective measures for reducing mortality in these patients.

Exploring the Impact of Obesity on Skeletal Muscle Function in Older Age

Sarcopenia is of important clinical relevance for loss of independence in older adults. The prevalence of obesity in combination with sarcopenia (“sarcopenic-obesity”) is increasing at a rapid rate. However, whilst the development of sarcopenia is understood to be multi-factorial and harmful to health, the role of obesity from a protective and damaging perspective on skeletal muscle in aging, is poorly understood. Specifically, the presence of obesity in older age may be accompanied by a greater volume of skeletal muscle mass in weight-bearing muscles compared with lean older individuals, despite impaired physical function and resistance to anabolic stimuli. Collectively, these findings support a potential paradox in which obesity may protect skeletal muscle mass in older age. One explanation for these paradoxical findings may be that the anabolic response to weight-bearing activity could be greater in obese vs. lean older individuals due to a larger mechanical stimulus, compensating for the heightened muscle anabolic resistance. However, it is likely that there is a complex interplay between muscle, adipose, and external influences in the aging process that are ultimately harmful to health in the long-term. This narrative briefly explores some of the potential mechanisms regulating changes in skeletal muscle mass and function in aging combined with obesity and the interplay with sarcopenia, with a particular focus on muscle morphology and the regulation of muscle proteostasis. In addition, whilst highly complex, we attempt to provide an updated summary for the role of obesity from a protective and damaging perspective on muscle mass and function in older age. We conclude with a brief discussion on treatment of sarcopenia and obesity and a summary of future directions for this research field.

The Role of Obesity in Early and Long-Term Outcomes after Surgical Excision of Lung Oligometastases from Colorectal Cancer

Obesity correlates with better outcomes in many neoplastic conditions. The aim of this study was to assess its role in the prognosis and morbidity of patients submitted to resection of lung oligometastases from colorectal cancer. Seventy-six patients undergoing a first pulmonary metastasectomy were retrospectively included in the study. Seventeen (22.3%) were obese (body mass index (BMI) >30 kg/m²). Assessed outcomes were overall survival, time to recurrence, and incidence of post-operative complications. Median follow-up was 33 months (IQR 16-53). At follow-up, 37 patients (48.6%) died, whereas 39 (51.4%) were alive. A significant difference was found in the 3-year overall survival (obese 80% vs. non-obese 56.8%, p = 0.035). Competing risk analysis shows that the cumulative incidence of recurrence was not different between the two groups. Multivariate analysis reveals that the number of metastases (p = 0.028), post-operative pneumonia (p = 0.042), and DFS (p = 0.007) were significant predictors of death. Competing risk regression shows that no independent risk factor for recurrence has been identified. The complication rate was not different between the two groups (17.6% vs. 13.6%, p = 0.70). Obesity is a positive prognostic factor for survival after pulmonary metastasectomy for colorectal cancer. Overweight patients do not experience more post-operative complications. Our results need to be confirmed by large multicenter studies.

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.

GNRI as a Prognostic Factor for Outcomes in Cancer Patients: A Systematic Review of the Literature

Oncologic patients often suffer from malnutrition which in turn, might have negative impact on treatment outcomes. The Geriatric Nutritional Risk Index (GNRI), as an index of impaired nutritional status, has emerged as a significant prognostic factor for short-and long-term outcomes in cancer patients. The aim of the current systematic review is to determine whether the GNRI is an independent prognostic factor of postoperative complications and survival in cancer patients. A systematic search was conducted to identify studies, published from 2005 to 2019, which assessed associations between GNRI and short- and long-term outcomes in cancer patients. Eighteen studies fulfilled the eligibility criteria and were included in the analysis. Low scores of GNRI were associated with increased risk for developing postoperative complications and impaired survival of cancer patients in most studies. Our findings support the use of the GNRI in the clinical practice, since it is a simple and reliable tool for assessing nutritional status in oncologic patients. More prospective, multi-centered studies are warranted to confirm the current results, as well as the role of nutritional support in improving the prognosis of cancer patients.

Pre-Disease and Pre-Surgery BMI, Weight Loss and Sarcopenia Impact Survival of Resected Lung Cancer Independently of Tumor Stage

Lower pre-surgery Body Mass Index (BMI) and low muscle mass impact negatively long-term survival of non-small cell lung cancer (NSCLC). We investigated their influence on survival after major lung resection for NSCLC.

METHODS

A retrospective analysis of a prospectively collected database was made on 304 consecutive patients.

RESULTS

Underweight, normal, overweight and obese patients represented 7.6%, 51.6%, 28.6%, and 12.6% of the pre-disease population. Weight loss and gain were recorded in 5% and 44.4% of patients, respectively. Low muscle mass was more frequently associated with BMI < 25 kg/m2 (p < 0.000001). Overall survival was positively affected by pre-disease (p = 0.036) and pre-surgery (p = 0.017) BMI > 25 kg/m2, and, even more, in case of BMI > 25 kg/m2 and increasing weight (p = 0.012). Long-term outcome was negatively influenced by low muscle mass (p = 0.042) and weight loss (p = 0.0052) as well as age (p = 0.017), ASA categories (p = 0.025), extent of resection (p = 0.0001), pleural invasion (p = 0.0012) and higher pathologic stage (p < 0.0001). Three stepwise multivariable models confirmed the independent favorable prognostic value of higher pre-disease (RR 0.66[0.49-0.89], p = 0.006) and pre-surgery BMI (RR 0.72[0.54-0.98], p = 0.034), and the absence of low muscle mass (RR 0.56[0.37-0.87], p = 0.0091).

CONCLUSIONS

Body reserves assessed by simple clinical markers impact survival of surgically treated NSCLC. Strategies improving body fat and muscular mass before surgery should be considered.

Does obesity impact the outcome of severely burned patients?

Although obesity appears to be an important predictor of mortality and morbidity, little data about the impact of body mass index (BMI) on the outcome of severely burned patients are available. Patients admitted to the General Hospital Vienna between 1994 and 2014, who underwent surgery because of burn injuries, were enrolled in this study. BMI was used to divide patients into five groups: BMI 18.5 to 24.9, 25 to 29.9, 30 to 34.9, 35 to 39.9, and > 40. The groups were compared in terms of difference of mortality and morbidity. Of 460 patients, 34.3% (n = 158) died. Mortality rates were the lowest in patients with obesity class III and the highest in patients with BMI 35 to 39.9 (BMI 18.5‐24.9: 30.5%, BMI 25‐29.9: 31.5%, BMI 30‐34.9: 41.3%, BMI 35‐39.9: 55.5%, BMI > 40: 30%; P = .031). BMI was not found to be an independent risk factor when corrected with age, percent total body surface area burned, full‐thickness burns, and inhalation injury. No significant differences in length of stay, inhalation trauma, pneumonia, wound infection, sepsis, and invasive ventilation were observed. BMI as an independent risk factor for severely burned patients could not be confirmed via multivariate analysis.

The Prognostic Values of a Novel Preoperative Inflammation-Based Score in Japanese Patients With Non-Small Cell Lung Cancer

Background

Several previous researchers have investigated the prognostic value of the combinations of systemic inflammatory markers. However, the prognostic power of these systemic inflammatory markers is not identical. We aimed to establish a novel prognostic score based on systemic inflammatory markers.

Methods

Four hundred non-small cell lung cancer (NSCLC) patients who underwent surgery and were followed more than 5 years were included. Univariate and multivariate analyses were calculated by the Cox proportional hazards regression model.

Results

Among systemic inflammatory markers which were used for the previously reported indexes, preoperative serum C-reactive protein (CRP) and body mass index (BMI) were independent prognostic markers in multivariate analysis, while serum albumin level, neutrophil to lymphocyte ratio and platelet to lymphocyte ratio were not. Based on this result, a novel score was established. Patients with both normal CRP (< 0.13 ng/dL) and high BMI (> 20.6 kg/m²) were allocated a score of 0. Patients in whom only one of these abnormalities was present were allocated a score of 1, whilst those with both high CRP and low BMI were given a score of 2. Patients with score 0 had 84.44% of 5-year cancer-specific survival, while patients with score 1 - 2 had a 61.88%. On multivariate analysis, this novel score was an independent prognostic factor.

Conclusion

This novel score based on CRP and BMI might serve as an efficient prognostic indicator in resected NSCLC.

Influence of obesity on in-hospital and postoperative outcomes of hepatic resection for malignancy: a 10-year retrospective analysis from the US National Inpatient Sample

OBJECTIVES

The influence of obesity on the outcomes of curative liver resection for malignancies remains controversial. We aimed to compare the in-hospital outcomes of liver resection for malignancy between obese and non-obese patients.

DESIGN

This was a population-based, retrospective, observational study using data from the Nationwide Inpatient Sample (NIS), the largest all-payer US inpatient care database.

SETTING

Hospitalisations of adults ≥18 years old with diagnoses of primary hepatobiliary malignancy or secondary malignant neoplasms of liver in the USA were identified from the NIS database between 2005 and 2014.

PARTICIPANTS

Data of 18 398 patients ≥18 years old and underwent liver resection without pancreatic resection in the NIS were extracted. All included subjects had primary hepatobiliary malignancy or secondary malignant neoplasms of the liver. Patients were divided into obese and non-obese groups. These groups were compared with respect to postoperative complications, length of hospital stay and hospital cost according to surgical extent and approach.

INTERVENTIONS

Patients were undergoing lobectomy of liver or partial hepatectomy.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary endpoints of this study were postoperative complications, length of hospital stay and hospital cost.

RESULTS

After adjustment, obese patients were significantly more likely to experience postoperative complications than were non-obese patients (adjusted OR 1.25, 95% CI 1.10 to 1.42), regardless of whether lobectomy or partial hepatectomy was performed. Furthermore, obesity was significantly associated with increased risk of postoperative complications in patients who underwent open liver resection, but not laparoscopic resection. No significant difference was observed in length of hospital stay or total hospital costs between obese and non-obese patients.

CONCLUSIONS

After adjustment for preoperative comorbidities and other potential confounders, obesity is significantly associated with greater risk of complications in patients undergoing open liver resection for malignancy, but not laparoscopic resection.

Modifiable Host Factors in Melanoma: Emerging Evidence for Obesity, Diet, Exercise, and the Microbiome

PURPOSE OF REVIEW

We discuss how potentially modifiable factors including obesity, the microbiome, diet, and exercise may impact melanoma development, progression, and therapeutic response.

RECENT FINDINGS

Obesity is unexpectedly associated with improved outcomes with immune and targeted therapy in melanoma, with early mechanistic data suggesting leptin as one mediator. The gut microbiome is both a biomarker of response to immunotherapy and a potential target. As diet is a major determinant of the gut microbiome, ongoing studies are examining the interaction between diet, the gut microbiome, and immunity. Data are emerging for a potential role of exercise in reducing hypoxia and enhancing anti-tumor immunity, though this has not yet been well-studied in the context of contemporary therapies. Recent data suggests energy balance may play a role in the outcomes of metastatic melanoma. Further studies are needed to demonstrate mechanism and causality as well as the feasibility of targeting these factors.

Estimated intraoperative blood loss correlates with postoperative cardiopulmonary complications and length of stay in patients undergoing video-assisted thoracoscopic lung cancer lobectomy: a retrospective cohort study

Background

The purpose of our study was to estimate the influence of estimated intraoperative blood loss (EIBL) on postoperative cardiopulmonary complications (PCCs) in patients undergoing video-assisted thoracoscopic surgery (VATS) lobectomy for non-small-cell lung cancer (NSCLC).

Methods

We conducted a single-center retrospective analysis on the clinical data of consecutive patients in our institution between April 2015 and February 2016. Demographic differences between PCC group and non-PCC group were initially assessed. Receiver operating characteristic (ROC) analysis was performed to determine the threshold value of EIBL for the prediction of PCCs. Demographic differences in the PCC rates and length of stay between two groups of patients divided by this cutoff were further evaluated. A multivariable logistic-regression model involving the clinicopathological parameters with P-value< 0.05 was finally established to identify independent risk factors for PCCs.

Results

A total of 429 patients with operable NSCLC were included and 80 of them developed PCCs (rate = 18.6%). The mean EIBL in PCC group was significantly higher than that in non-PCC group (133.3 ± 191.3 vs. 79.1 ± 107.1 mL; P < 0.001). The ROC analysis showed an EIBL of 100 mL as the threshold value at which the joint sensitivity (50.0%) and specificity (73.4%) was maximal. The PCC rate in patients with EIBL≥100 mL was significantly higher than that in patients with EIBL< 100 mL (30.1 vs. 13.5%; P < 0.001). Both the length of stay and chest tube duration were significantly prolonged in the patients with EIBL≥100 mL. Finally, EIBL≥100 mL was identified to be predictive of PCCs by multivariable logistic-regression analysis (odds ratio = 3.01; 95% confidence interval = 1.47–6.16; P = 0.003).

Conclusions

EIBL serves as a significant categorical predictor for cardiopulmonary complications following VATS lobectomy for NSCLC. Thoracic surgeons should minimize the EIBL and strive for the ‘bloodless’ goal to optimize surgical outcomes.

Electronic supplementary material

The online version of this article (10.1186/s12893-018-0360-0) contains supplementary material, which is available to authorized users.

Association of body mass index and outcomes following lobectomy for non-small-cell lung cancer

Background

Obesity and overweight have become increasingly prevalent, but no consensus has been reached regarding the effect of body mass index (BMI) on surgical outcomes. In this study, we sought to examine the influence of BMI on perioperative outcomes in a large cohort of patients with non-small-cell lung cancer (NSCLC) who underwent lobectomy.

Methods

A retrospective study was conducted in 1198 patients who underwent lobectomy for primary NSCLC at Shandong Provincial Hospital between November 2006 and January 2017. BMI was calculated using measured height and weight on admission and categorized as obese (≥ 30 kg/m²), overweight (25 to 29.9 kg/m²), normal (18.5 to 24.9 kg/m²), or underweight (< 18.5 kg/m²). Patients’ baseline characteristics and outcomes were abstracted from medical records following institutional review board approval. Endpoints included operative mortality, perioperative complications, and length of stay (LOS). Complications were divided into four groups as respiratory, cardiovascular, other, and overall. Logistic regression models were constructed to assess the association between BMI and adverse outcomes.

Results

When compared with normal BMI, obesity and overweight did not increase the risk of complications in any category, operative mortality, or prolonged LOS. In fact, the incidence of operative mortality and respiratory complications tended to be lower in overweight patients than in normal weight patients (P = 0.047 and P = 0.041, respectively). Conversely, underweight patients experienced significantly more operative mortality, respiratory complications, and prolonged LOS (P = 0.004, P = 0.011, and P = 0.003, respectively).

Conclusions

Obesity and overweight did not confer adverse surgical outcomes. Underweight patients presented increased risk of respiratory complications, perioperative death, and prolonged LOS. Thus, overweight and obesity should not be a relative contraindication for lobectomy. Meanwhile, nurses and surgeons should focus on perioperative management of underweight patients.

The obesity paradox in cancer: clinical insights and perspectives

A series of evidence demonstrated that obesity represents an established risk factor for an increase in the incidence of multiple cancer types and for poor cancer survival. Nevertheless, recent studies suggested that, in a series of cancers, patients with a normal body mass index (BMI) have worse outcomes than obese patients. This phenomenon, named 'obesity paradox' or 'reverse epidemiology' in cancer, is not well understood and presents controversial aspects. Therefore, this review aims to explore the available studies concerning the relationship between obesity and cancer incidence or survival and to highlight the hypothetical explanations and the methodological framework. In this regard, we underline the limits of BMI as a potential marker of adiposity and the relevance to assessing body composition, beyond the body size. Further studies are needed to define the impact of obesity in cancer patients, to tailor weight management after cancer diagnosis and to hopefully improve overall clinical outcome.

Effects of degree of pulmonary fissure completeness on major in-hospital outcomes after video-assisted thoracoscopic lung cancer lobectomy: a retrospective-cohort study

Background

To evaluate the clinical significance of degree of pulmonary fissure completeness (PFC) on major in-hospital outcomes following video-assisted thoracoscopic (VATS) lobectomy for non-small-cell lung cancer (NSCLC).

Materials and methods

We carried out a single-center retrospective analysis on the prospectively maintained database at our unit between August 2014 and October 2015. Patients were divided into two groups based on their fissure sum average (FSA). Patients with FSA >1 (1< FSA ≤3) were considered to have incomplete pulmonary fissures (group A), while patients with FSA of 0–1 were considered to have complete pulmonary fissures (group B). Demographic differences in perioperative characteristics and surgical outcomes between these two groups were initially assessed. Then, a multivariate logistic-regression analysis was further conducted to identify the independent predictors for major in-hospital outcomes.

Results

A total of 563 patients undergoing VATS lobectomy for NSCLC were enrolled. There were 190 patients in group A and 373 patients in group B. The overall morbidity and mortality rates of our cohort were 30.6% and 0.5%, respectively. Group A patients had a significantly higher overall morbidity rate than group B patients (42.1% vs 24.7%, P<0.001). Both minor morbidity (40.5% vs 22%, P<0.001) and major morbidity (11.1% vs 5.6%, P=0.021) rates in group A patients were also significantly higher than group B patients. No significant difference was observed in mortality rate between these two groups (1.1% vs 0.3%, P=0.26). The incomplete degree of PFC was significantly correlated with length of stay and chest-tube duration (log-rank P<0.001) after surgery. Finally, the incomplete degree of PFC was found to be predictive of overall morbidity (OR 2.08, P<0.001), minor morbidity (OR 2.39, P<0.001), and major morbidity (OR 2.06, P=0.031) by multivariate logistic-regression analyses.

Conclusion

Degree of PFC is an excellent categorical predictor for both major and minor morbidity after VATS lobectomy for NSCLC.

Presence of pleural adhesions can predict conversion to thoracotomy and postoperative surgical complications in patients undergoing video-assisted thoracoscopic lung cancer lobectomy

Background

The purpose of our cohort study was to investigate the effects of pleural adhesions on perioperative outcomes in patients undergoing video-assisted thoracoscopic surgery (VATS) lobectomy for non-small-cell lung cancer (NSCLC).

Methods

We performed a single-center retrospective analysis on the prospectively-maintained dataset at our unit from February 2014 to November 2015. Patients were divided into two groups (Group A: presence of pleural adhesions; Group B: absence of pleural adhesions) according to our grading system of pleural adhesions when entering the chest cavity. Demographic differences in perioperative outcomes between these two groups were initially estimated. A multivariate logistic-regression analysis was then performed to confirm the predictive value of the presence of pleural adhesions.

Results

A total of 593 NSCLC patients undergoing VATS lobectomy were enrolled. The conversion and postoperative morbidity rates were 3.2% and 29.2%, respectively. There were 154 patients with pleural adhesions (Group A) and 439 patients without pleural adhesions (Group B). Group A patients had significantly higher rates of conversion to thoracotomy (9.1% vs. 1.1%; P<0.001) and surgical complications (24.0% vs. 14.4%; P=0.006) than those of Group B patients. No significant difference was found in the overall morbidity and cardiopulmonary complication rates between these two groups. The presence of pleural adhesions was also significantly associated with the prolonged length of chest tube drainage (log-rank P<0.001) and length of stay (log-rank P=0.032). Finally, the presence of pleural adhesions was identified as an independent risk factor for conversion to thoracotomy [odds ratio (OR) =5.49; P=0.003] and surgical complications (OR =1.94; P=0.033) by multivariate logistic-regression analyses.

Conclusions

Presence of pleural adhesions can predict conversion to thoracotomy and postoperative surgical complications in patients undergoing VATS lobectomy for NSCLC. Our study calls for an internationally accepted grading system for the presence of pleural adhesions to stratify the surgical risk.

Enhanced recovery programs in lung cancer surgery: systematic review and meta-analysis of randomized controlled trials

Background

Enhanced recovery after surgery (ERAS) program is an effective evidence-based multidisciplinary protocol of perioperative care, but its roles in thoracic surgery remain unclear. This systematic review of randomized controlled trials (RCTs) aims to investigate the efficacy and safety of the ERAS programs for lung cancer surgery.

Materials and methods

We searched the PubMed and EMBASE databases to identify the RCTs that implemented an ERAS program encompassing more than four care elements within at least two phases of perioperative care in lung cancer surgery. The heterogeneity levels between studies were estimated by the Cochrane Collaborations. A qualitative review was performed if considerable heterogeneity was revealed. Relative risk (RR) and weighted mean difference served as the summarized statistics for the meta-analyses. Additional analyses were also performed to perceive potential bias risks.

Results

A total of seven RCTs enrolling 486 patients were included. The meta-analysis indicated that the ERAS group patients had significantly lower morbidity rates (RR=0.64; p<0.001), especially the rates of pulmonary (RR=0.43; p<0.001) and surgical complications (RR=0.46; p=0.010), than those of control group patients. No significant reduction was found in the in-hospital mortality (RR=0.70; p=0.58) or cardiovascular complications (RR=1.46; p=0.25). In the qualitative review, most of the evidence reported significantly shortened length of hospital and intensive care unit stay and decreased hospitalization costs in the ERAS-treated patients. No significant publication bias was detected in the meta-analyses.

Conclusion

Our review demonstrates that the implementation of an ERAS program for lung cancer surgery can effectively accelerate postoperative recovery and save hospitalization costs without compromising patients’ safety. A worldwide consensus guideline is urgently required to standardize the ERAS protocols for elective lung resections in the future.

[Enhanced Lung Recovery after Surgery, Is It A Necessary for Precision Therapy?]

背景与目的

绿原酸类物质可通过调节细胞周期、诱导凋亡、抑制细胞生长等途径产生抗癌作用，Notch信号通路与人类许多肿瘤都存在密切的关系，本研究旨在探讨绿原酸通过Notch1信号通路控制非小细胞肺癌细胞凋亡的作用机制，为临床应用以及Notch1靶向药物的研究提供依据。

方法

MTT法检测不同浓度的绿原酸对非小细胞肺癌细胞系A549细胞形态和细胞增殖的影响；流式细胞仪检测绿原酸对A549细胞的凋亡和细胞周期的影响；建立A549细胞的裸鼠荷瘤模型；测量肿瘤大小和重量；实时荧光定量PCR法检测Notch信号通路相关因子的mRNA表达水平；免疫印迹法检测Notch信号通路相关因子的蛋白表达水平。

结果

绿原酸抑制A549细胞增殖，诱导A549细胞凋亡，增加细胞G₂期/M期细胞百分比增加（P < 0.05），并且呈现剂量依赖趋势。在A549细胞的裸鼠荷瘤模型中，实验组肿瘤大小和体积明显小于对照组，差异具有统计学意义（P < 0.01）。试验组Notch1、VEGF、Delta4、HES1、HEY1 mRNA表达量较对照组明显减少（P < 0.05）。实验组Notch1蛋白明显减少，PTEN、p-PTEN、p-AKT明显增加（P < 0.05）。

结论

在动物水平，绿原酸可能通过Notch1信号通路调控非小细胞肺癌的凋亡，可能是通过减少VEGF的表达，下调Delta 4水平，从而抑制Notch1信号通路的活化。Notch1信号通路可能通过PTEN与PI3K/AKT通路存在交叉调控作用。

Body surface area: a novel predictor for conversion to thoracotomy in patients undergoing video-assisted thoracoscopic lung cancer lobectomy

BACKGROUND

The purpose of our study was to explore the value of body surface area (BSA) for predicting conversion to thoracotomy in patients undergoing video-assisted thoracoscopic (VATS) lobectomy for non-small cell lung cancer (NSCLC).

METHODS

We performed a monocentric retrospective analysis based on a prospectively-maintained dataset of consecutive patients between March 2014 and August 2015 at our unit. The median value of BSA was used as the cut-off. Patients with BSA > median value were classified as the "large" group, while those with BSA ≤ median value were classified as the "non-large" group. The conversion rate and post-VATS morbidity between these two groups were evaluated. Finally, a multivariate logistic-regression analysis was performed to identify the predictors for conversion to thoracotomy.

RESULTS

A total of 475 patients with a median BSA of 1.73 m² were enrolled. There were 16 patients converted to thoracotomy (ratio =3.4%). The overall morbidity rate was 28.4%. The "large" group (BSA >1.73 m²) included 236 patients, while the "non-large" group (BSA ≤1.72 m²) included the remaining 239 patients. The conversion (5.5% vs. 1.3%; P=0.010) in the "large" patients was significantly higher than that in the "non-large" patients. No difference was found in the overall morbidity rate between these two groups (32.2% vs. 24.7%; P=0.069). The multivariate logistic-regression analysis demonstrated that BSA >1.73 m² could be a strongly independent predictor for conversion to thoracotomy [odds ratio (OR): 7.17; P=0.028].

CONCLUSIONS

BSA is an excellent categorical predictor for conversion to thoracotomy in NSCLC patients undergoing VATS lobectomy. It may be considered when informing patients about intraoperative risks and selecting cases in the early learning curve of VATS techniques.

[Evidence and Practice of Enhanced Lung Recovery after Surgery in Patients Undergoing Lung Surgery]

加速康复外科（enhanced recovery after surgery, ERAS）方案临床应用的多样性，取决于病种和团队而不同。肺术后都有哪些证据有利于加速肺康复（enhanced lung recovery after surgery, ELRAS）的临床实践呢？本文主要从围手术期可采用的措施及方法进行回顾性分析：术前强调教育及高危因素的评估及预防，术中微创手术及流程优化，术后关注以疼痛为主的症状管理。

Body surface area is a novel predictor for surgical complications following video-assisted thoracoscopic surgery for lung adenocarcinoma: a retrospective cohort study

Background

Body surface area (BSA) is a biometric unit to measure the body size. Its clinical significance in video-assisted thoracoscopic surgery (VATS) was rarely understood. We aimed to estimate the predictive value of BSA for surgical complications following VATS anatomical resections for lung adenocarcinoma (LAC).

Methods

A single-center retrospective analysis was performed on the consecutive patients between July 2014 and January 2016 in our institution. The differences in mean BSA values were evaluated between groups of patients classified by the development of postoperative surgical complications (PSCs), overall morbidity and cardiopulmonary complications, respectively. Receiver operating characteristic (ROC) analysis was performed to determine a threshold value of BSA on prediction of PSC occurrence. A multivariate logistic-regression model involving this optimal cut-off value and other significant parameters was established to identify the predictors for PSCs.

Results

During the study period, a total of 442 patients undergoing VATS anatomical resections for LAC were enrolled in this study. There were 135 patients developed with one or more complications (rate = 30.5%). PSCs occupied the largest percentages of all these complications (n = 81, rate = 18.3%). The mean BSA in PSC group was significantly higher than that in non-PSC group (1.76 ± 0.15 m² vs 1.71 ± 0.16 m²; P = 0.016). No difference was found in mean BSA values between groups classified by any other complication. The ROC analysis determined a BSA value of 1.68 m² to be the threshold value with the maximum joint sensitivity of 72.8% and specificity of 48.5%. Compared to patients with BSA ≤ 1.68 m², patients with BSA > 1.68 m² had significantly higher incidences of prolonged air leak (P = 0.006) and chylothorax (P = 0.004). Further multivariate logistic-regression analysis indicated that BSA > 1.68 m² could be an independent risk factor for PSCs (odds ratio: 2.03; P = 0.025).

Conclusions

BSA is an excellent categorical predictor for surgical complications following VATS anatomical resections for LAC. It may be considered when informing patients about surgical risks and selecting cases in the early learning curve. Large-scale and multi-institutional studies are expected to confirm and modify our findings in the future.

Electronic supplementary material

The online version of this article (doi:10.1186/s12893-017-0264-4) contains supplementary material, which is available to authorized users.

The Influence of Body Mass Index on Overall Survival Following Surgical Resection of Non-Small Cell Lung Cancer

BACKGROUND

Population studies suggest that high body mass index (BMI) correlates with a reduced risk for death from lung cancer. The aim of our study was to evaluate definitively the influence of BMI on long-term overall survival (OS) in surgical patients with NSCLC.

METHODS

The study population consisted of 1935 patients who underwent surgical resection for lung cancer at M. D. Anderson Cancer Center (2000-2014). Study variables included both patient- and treatment-related characteristics. Univariate and multivariate Cox regression analyses were performed to identify variables associated with OS.

RESULTS

On univariate analysis, significant predictors of improved survival were higher BMI, pathologic tumor stage (stage I versus stage II, III, or IV), type of surgical procedure (lobectomy/pneumonectomy versus wedge resection/segmentectomy), younger age, female sex, and adenocarcinoma histologic subtype (versus squamous) (all p < 0.05). Morbidly obese patients (BMI ≥ 35) demonstrated a trend toward better outcomes than those classified as obese (BMI ≥30 and <35 kg/m²) (p = 0.05), overweight (BMI ≥ 25 and <30 kg/m²) (p = 0.13), or healthy weight (BMI <25 kg/m²) (p = 0.37) (hazard ratio = 0.727, 0.848, 0.926, and 1, respectively). On multivariate analysis, BMI remained an independent predictor of survival (p = 0.02). Propensity matching analysis demonstrated significantly better OS (p = 0.003) in patients with a BMI of 30 kg/m² or higher as compared with a BMI of 25 kg/m².

CONCLUSIONS

In this large, retrospective, single-center series, after control for disease stage and other variables, higher BMI was associated with improved OS after surgical resection of NSCLC. Further studies are necessary to elucidate the precise relationship between BMI and treatment outcomes.