The association between preoperative cardiopulmonary exercise-test variables and short-term morbidity after esophagectomy: A hospital-based cohort study

Sex differences in survival following surgery for esophageal cancer: A systematic review and meta-analysis

The impact of sex on the prognosis of patients with esophageal cancer remains unclear. Evidence supports that sex- based disparities in esophageal cancer survival could be attributed to sex- specific risk exposures, such as age at diagnosis, race, socioeconomic status, smoking, drinking, and histological type. The aim of our study is to investigate the role of sex disparities in survival of patients who underwent surgery for esophageal cancer. A systematic review and meta-analysis of the existing literature in PubMed, EMBASE, and CENTRAL from December 1966 to February 2023, was held. Studies that reported sex-related differences in survival outcomes of patients who underwent esophagectomy for esophageal cancer were identified. A total of 314 studies were included in the quantitative analysis. Statistically significant results derived from 1-year and 2-year overall survival pooled analysis with Relative Risk (RR) 0.93 (95% Confidence Interval (CI): 0.90-0.97, I2 = 52.00) and 0.90 (95% CI: 0.85-0.95, I2 = 0.00), respectively (RR < 1 = favorable for men). In the postoperative complications analysis, statistically significant results concerned anastomotic leak and heart complications, RR: 1.08 (95% CI: 1.01-1.16) and 0.62 (95% CI: 0.52-0.75), respectively. Subgroup analysis was performed among studies with <200 and > 200 patients, histology types, study continent and publication year. Overall, sex tends to be an independent prognostic factor for esophageal carcinoma. However, unanimous results seem rather obscure when multivariable analysis and subgroup analysis occurred. More prospective studies and gender-specific protocols should be conducted to better understand the modifying role of sex in esophageal cancer prognosis.

Cardiopulmonary exercise variables and their association with postoperative morbidity and mortality after major oesophagogastric cancer surgery-a multicentre observational study

Background

Outcomes after oesophagogastric cancer surgery remain poor. Cardiopulmonary exercise testing (CPET) used for risk stratification before oesophagogastric cancer surgery is based on conflicting evidence. This study explores the relationship between CPET and postoperative outcomes, specifically for patients undergoing neoadjuvant treatment.

Methods

Patients undergoing oesophagogastric cancer resection and CPET (pre- or post-neoadjuvant treatment, or both) were retrospectively enrolled into a multicentre pooled cohort study. Oxygen uptake at peak exercise (VO2 peak) was compared with 1-yr postoperative survival. Secondary analyses explored relationships between patient characteristics, tumour pathology characteristics, CPET variables (absolute, relative to weight, ideal body weight, and body surface area), and postoperative outcomes (morbidity, 1-yr and 3-yr survival) were assessed using logistic regression analyses.

Results

Seven UK centres recruited 611 patients completing a 3-yr postoperative follow-up period. Oesophagectomy was undertaken in 475 patients (78%). Major complications occurred in 25%, with 18% 1-yr and 43% 3-yr mortality. No association between VO2 peak or other selected CPET variables and 1-yr survival was observed in the overall cohort. In the overall cohort, the anaerobic threshold relative to ideal body weight was associated with 3-yr survival (P=0.013). Tumour characteristics (ypT/ypN/tumour regression/lymphovascular invasion/resection margin; P<0.001) and Clavien-Dindo ≥3a (P<0.001) were associated with 1-yr and 3-yr survival. On subgroup analyses, pre-neoadjuvant treatment CPET; anaerobic threshold (absolute; P=0.024, relative to ideal body weight; P=0.001, body surface area; P=0.009) and VE/VCO2 at anaerobic threshold (P=0.026) were associated with 3-yr survival. No other CPET variables (pre- or post-neoadjuvant treatment) were associated with survival.

Conclusions

VO2 peak was not associated with 1-yr survival after oesophagogastric cancer resection. Tumour characteristics and major complications were associated with survival; however, only some selected pre-neoadjuvant treatment CPET variables were associated with 3-yr survival. CPET in this cohort of patients demonstrates limited outcome predictive precision.

Clinical trial registration

NCT03637647.

Identifying the limitations of cardiopulmonary exercise testing prior to esophagectomy using a pooled analysis of patient-level data

Preoperative cardiopulmonary exercise testing (CPET) provides an objective assessment of aerobic fitness in patients undergoing surgery. While peak oxygen uptake during exercise (VO2peak) and anaerobic threshold have demonstrated a moderate correlation with the development of complications following esophagectomy, no clinically useful threshold values have been defined. By pooling patient level data from existing studies, we aimed to define optimal thresholds for preoperative CPET parameters to predict patients at high risk of postoperative complications. Studies reporting on the relationship between preoperative CPET variables and post-esophagectomy complications were determined from a comprehensive literature search. Patient-level data were obtained from six contributing centers for pooled-analyses. Outcomes of interest included cardiopulmonary and non-cardiopulmonary complications, unplanned intensive care unit readmission, and 90-day and 12-month all-cause mortality. Receiver operating characteristic curves and logistic regression models estimated the predictive value of CPET parameters for each individual outcome of interest. This analysis comprised of 621 patients who underwent CPET prior to esophagectomy during the period from January 2004 to March 2017. For both anaerobic threshold and VO2peak, none of the receiver operating characteristic curves achieved an area under the curve value > 0.66 for the outcomes of interest. The discriminatory ability of CPET for determining high-risk patients was found to be poor in patients undergoing an esophagectomy. CPET may only carry an adjunct role to clinical decision-making.

Decrease of physical fitness during neoadjuvant chemoradiotherapy predicts the risk of pneumonia after esophagectomy

Although neoadjuvant chemoradiotherapy (nCRT) is frequently used in esophageal cancer patients undergoing treatment with curative intent, it can negatively impact patients' physical fitness. A decline in physical fitness during chemoradiotherapy may be an indication of vulnerability. The aim of this study was to evaluate whether changes in physical fitness, weight, and fat-free mass index (FFMI) during nCRT can predict the risk of postoperative pneumonia. A retrospective longitudinal observational cohort study was performed in patients who received curative treatment for esophageal cancer between September 2016 and September 2018 in a high-volume center for esophageal cancer surgery. Physical fitness (handgrip strength, leg extension strength, and exercise capacity), weight, and FFMI were measured before and after chemoradiotherapy. To be included in the data analyses, pre- and post-nCRT data had to be available of at least one of the outcome measures. Logistic regression analyses were performed to evaluate the predictive value of changes in physical fitness, weight, and FFMI during nCRT on postoperative pneumonia, as defined by the Uniform Pneumonia Scale. In total, 91 patients were included in the data analyses. Significant associations were found between the changes in handgrip strength (odds ratio [OR] 0.880, 95% confidence interval [CI]: 0.813-0.952) and exercise capacity (OR 0.939, 95%CI: 0.887-0.993) and the occurrence of postoperative pneumonia. All pneumonias occurred in patients with declines in handgrip strength and exercise capacity after nCRT. A decrease of handgrip strength and exercise capacity during nCRT predicts the risk of pneumonia after esophagectomy for cancer. Measuring physical fitness before and after chemoradiotherapy seems an adequate method to identify patients at risk of postoperative pneumonia.

Exercise capacity in the stair-climbing test predicts outcomes of operable esophageal cancer in minimally invasive era

INTRODUCTION

The risk of complications after esophagectomy highlights the need for careful preoperative assessment. Aim was to assess whether stair-climbing test (SCT) could predict outcomes of patients with operable esophageal cancer in minimally invasive era.

MATERIALS AND METHODS

Patients with esophageal cancer were evaluated for surgical treatment in Central Finland Central Hospital from 2012 to March 2021. Of evaluated 162 patients, 138 were scheduled to eventually undergo surgery. The exercise capacity was evaluated with symptom limited SCT. Patients were divided into four study groups on intent-to-treat basis: surgery and the SCT >14 m (Group 1), surgery and the SCT <11 m (Group 2), non-surgical therapy and the SCT <11 m (Group 3) and non-surgical therapy and the SCT >14 m (Group 4). Results were adjusted for confounders.

RESULTS

Major complication rate was 10.1% vs 40.0% between Group 1 and 2 (p = 0.006), and 90-day mortality 0% vs 20.0% (p < 0.001). Overall survival rates in Groups 1-4 at 1-year were 92.3% vs 72.2% vs 46.8% vs 81.8%, at 3-year 68.5% vs 52.7% vs 15.6% vs 27.3% and at 5-year 58.7% vs 39.5% vs 0% vs 0%, respectively (p < 0.001). In adjusted analysis when compared to Group 1, other groups had increased 5-year mortality hazard (Group 2 HR 2.88 (95% CI 1.25-6.63), Group 3 HR 15.6 (95% CI 5.57-43.5) and Group 4 HR 5.35 (95% CI 2.08-13.7)).

CONCLUSION

Exercise capacity measured with SCT in esophageal cancer patients is a strong predictor of complications and survival, and is a potential parameter to be included in any risk or prognostic models.

Preoperative Cardiopulmonary Exercise Test Associated with Postoperative Outcomes in Patients Undergoing Cancer Surgery: A Systematic Review and Meta-Analyses

BACKGROUNDS

There is mixed evidence on the value of preoperative cardiorespiratory exercise test (CPET) to predict postoperative outcomes in patients undergoing a cancer surgical procedure. The purpose of this review was to investigate the association between preoperative CPET variables and postoperative complications, length of hospital stay, and quality of life in patients undergoing cancer surgery.

METHODS

A search was conducted on MEDLINE, Embase, AMED, and Web of science from inception to April 2020. Cohort studies investigating the association between preoperative CPET variables, including peak oxygen uptake (peak VO₂), anaerobic threshold (AT), or ventilatory equivalent for carbon dioxide (V_E/V_CO2), and postoperative outcomes (complications, length of stay, and quality of life) were included. Risk of bias was assessed using the QUIPS tool. A random-effect model meta-analysis was performed whenever possible.

RESULTS

Fifty-two unique studies, including 10,030 patients were included. Overall, most studies were rated as having low risk of bias. Higher preoperative peak VO₂ was associated with absence of postoperative complications (mean difference [MD]: 2.28; 95% confidence interval [CI]: 1.26-3.29) and no pulmonary complication (MD: 1.47; 95% CI: 0.49-2.45). Preoperative AT and V_E/V_CO2 also demonstrated some positive trends. None of the included studies reported a negative trend.

CONCLUSIONS

This systematic review and meta-analysis demonstrated a significant association between superior preoperative CPET values, especially peak VO₂, and better postoperative outcomes. The assessment of preoperative functional capacity in patients undergoing cancer surgery has the potential to facilitate treatment decision making.

Does Cardiopulmonary Testing Help Predict Long-Term Survival After Esophagectomy?

Background

Esophagectomy is associated with a high rate of morbidity and mortality. Preoperative cardiopulmonary fitness has been correlated with outcomes of major surgery. Variables derived from cardiopulmonary exercise testing (CPET) have been associated with postoperative outcomes. It is unclear whether preoperative cardiorespiratory fitness of patients undergoing esophagectomy is associated with long-term survival. This study aimed to evaluate whether any of the CPET variables routinely derived from patients with esophageal cancer may aid in predicting long-term survival after esophagectomy.

Methods

Patients undergoing CPET followed by trans-thoracic esophagectomy for esophageal cancer with curative intent between January 2013 and January 2017 from single high-volume center were retrospectively analyzed. The relationship between predictive co-variables, including CPET variables and survival, was studied with a Cox proportional hazard model. Receiver operation curve (ROC) analysis was performed to find cutoff values for CPET variables predictive of 3-year survival.

Results

The study analyzed 313 patients. The ventilatory equivalent for carbon dioxide (VE/VCO₂) at the anerobic threshold was the only CPET variable independently predictive of long-term survival in the multivariable analysis (hazard ratio [HR], 1.049; 95% confidence interval [CI], 1.011–1.088; p = 0.011). Pathologic stages 3 and 4 disease was the other co-variable found to be independently predictive of survival. An ROC analysis of the VE/VCO₂ failed to demonstrate a predictive cutoff value of 3-year survival (area under the curve, 0.564; 95% CI, 0.499–0.629; p = 0.056).

Conclusions

A high VE/VCO₂ before esophagectomy for malignant disease is an independent predictor of long-term survival and may be an important variable for clinicians to consider when counseling patients.

Myosteatosis predicts higher complications and reduced overall survival following radical oesophageal and gastric cancer surgery

INTRODUCTION

Low muscle attenuation, as governed by increased intramuscular fat infiltration (myosteatosis), may associate with adverse surgical outcomes. We aimed to determine whether myosteatosis is associated with an increased risk of postoperative complications and reduced long-term survival after oesophago-gastric (OG) cancer surgery.

METHODS

Patients who underwent radical OG cancer surgery with preoperative abdominal computed tomography (CT) imaging were included. Myosteatosis was evaluated using previously defined cut-points for low skeletal muscle attenuation measured by CT. Oncological, surgical, complications, and outcome data were obtained from a prospective database.

RESULTS

Of 108 patients, 56% (n = 61) had myosteatosis. Patients with myosteatosis were older (69.1 ± 9.1 vs. 62.8 ± 9.8 years, p = 0.001) and had a similar body mass index (BMI) (23.4 ± 5.3 vs. 25.9 ± 6.7 kg/m², p = 0.766) compared to patients with normal muscle attenuation. Patients with myosteatosis had a higher rate of anastomotic leaks (15% vs. 2%, p = 0.041). On multivariate analysis, myosteatosis was an independent predictor of overall (OR 3.03, 95% CI 1.31-6.99, p = 0.009) and severe complications (OR 4.33, 95% CI 1.26-14.9, p = 0.020). Patients with myosteatosis had reduced 5 year overall (54.1% vs. 83%, p = 0.004) and disease-free (55.2% vs. 87.2%, p = 0.007) survival.

CONCLUSION

Myosteatosis is associated with a significantly increased risk of overall and severe complications as well as substantially reduced long-term survival. Assessment of muscle attenuation provides analysis beyond standard anthropometrics and may form part of preoperative physiological staging tools used to improve surgical outcomes.

Cardiopulmonary Exercise Testing in Oesophagogastric Surgery: a Systematic Review

BACKGROUND

Cardiopulmonary exercise testing (CPX) can objectively measure fitness and oxygen uptake at anaerobic threshold. The relationship between fitness and postoperative outcomes after upper gastro-intestinal surgery is unclear. The aim of the present review is to assess the prognostic ability of CPX in predicting postoperative outcome associated with oesophagogastric surgery.

METHODS

Relevant studies were identified through a systematic search of EMBASE, Medline, CINAHL, Cochrane Library, and Web of Science to July 2019. The eligibility criteria for studies included prognostic studies of upper gastro-intestinal surgery among adult populations using a preoperative CPX and measurement of postoperative outcome (mortality or morbidity or length of stay). Risk of bias was assessed using the QUIPS Quality in Prognostic Studies validated tool.

RESULTS

Thirteen papers with a total of 1735 participants were included in data extraction. A total of 7 studies examined the association between CPX variables and postoperative mortality. Patients undergoing gastro-intestinal surgery with lower anaerobic threshold values were found to have an increased risk of postoperative mortality. Similarly, a lower rate of oxygen consumption was found to be associated with higher mortality. There was conflicting evidence regarding the association between CPX variables and postoperative morbidity. The evidence did not demonstrate any association between preoperative CPX variables and hospital length of stay.

CONCLUSION

Studies report an association between CPX variables and postoperative mortality; however, there is conflicting evidence regarding the association between CPX variables and postoperative morbidity.

Performance of cardiopulmonary exercise testing for the prediction of post-operative complications in non cardiopulmonary surgery: A systematic review

INTRODUCTION

Cardiopulmonary exercise testing (CPET) is widely used within the United Kingdom for preoperative risk stratification. Despite this, CPET's performance in predicting adverse events has not been systematically evaluated within the framework of classifier performance.

METHODS

After prospective registration on PROSPERO (CRD42018095508) we systematically identified studies where CPET was used to aid in the prognostication of mortality, cardiorespiratory complications, and unplanned intensive care unit (ICU) admission in individuals undergoing non-cardiopulmonary surgery. For all included studies we extracted or calculated measures of predictive performance whilst identifying and critiquing predictive models encompassing CPET derived variables.

RESULTS

We identified 36 studies for qualitative review, from 27 of which measures of classifier performance could be calculated. We found studies to be highly heterogeneous in methodology and quality with high potential for bias and confounding. We found seven studies that presented risk prediction models for outcomes of interest. Of these, only four studies outlined a clear process of model development; assessment of discrimination and calibration were performed in only two and only one study undertook internal validation. No scores were externally validated. Systematically identified and calculated measures of test performance for CPET demonstrated mixed performance. Data was most complete for anaerobic threshold (AT) based predictions: calculated sensitivities ranged from 20-100% when used for predicting risk of mortality with high negative predictive values (96-100%). In contrast, positive predictive value (PPV) was poor (2.9-42.1%). PPV appeared to be generally higher for cardiorespiratory complications, with similar sensitivities. Similar patterns were seen for the association of Peak VO2 (sensitivity 85.7-100%, PPV 2.7-5.9%) and VE/VCO2 (Sensitivity 27.8%-100%, PPV 3.4-7.1%) with mortality.

CONCLUSIONS

In general CPET's 'rule-out' capability appears better than its ability to 'rule-in' complications. Poor PPV may reflect the frequency of complications in studied populations. Our calculated estimates of classifier performance suggest the need for a balanced interpretation of the pros and cons of CPET guided pre-operative risk stratification.