Risk adjustment models for short-term outcomes after surgical resection for oesophagogastric cancer

International External Validation of Risk Prediction Model of 90-Day Mortality after Gastrectomy for Cancer Using Machine Learning

BACKGROUND

Radical gastrectomy remains the main treatment for gastric cancer, despite its high mortality. A clinical predictive model of 90-day mortality (90DM) risk after gastric cancer surgery based on the Spanish EURECCA registry database was developed using a matching learning algorithm. We performed an external validation of this model based on data from an international multicenter cohort of patients.

METHODS

A cohort of patients from the European GASTRODATA database was selected. Demographic, clinical, and treatment variables in the original and validation cohorts were compared. The performance of the model was evaluated using the area under the curve (AUC) for a random forest model.

RESULTS

The validation cohort included 2546 patients from 24 European hospitals. The advanced clinical T- and N-category, neoadjuvant therapy, open procedures, total gastrectomy rates, and mean volume of the centers were significantly higher in the validation cohort. The 90DM rate was also higher in the validation cohort (5.6%) vs. the original cohort (3.7%). The AUC in the validation model was 0.716.

CONCLUSION

The externally validated model for predicting the 90DM risk in gastric cancer patients undergoing gastrectomy with curative intent continues to be as useful as the original model in clinical practice.

Prediction of Morbidity and Mortality After Esophagectomy: A Systematic Review

BACKGROUND

Esophagectomy for esophageal cancer has a complication rate of up to 60%. Prediction models could be helpful to preoperatively estimate which patients are at increased risk of morbidity and mortality. The objective of this study was to determine the best prediction models for morbidity and mortality after esophagectomy and to identify commonalities among the models.

PATIENTS AND METHODS

A systematic review was performed in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and was prospectively registered in PROSPERO ( https://www.crd.york.ac.uk/prospero/ , study ID CRD42022350846). Pubmed, Embase, and Clarivate Analytics/Web of Science Core Collection were searched for studies published between 2010 and August 2022. The Prediction model Risk of Bias Assessment Tool was used to assess the risk of bias. Extracted data were tabulated and a narrative synthesis was performed.

RESULTS

Of the 15,011 articles identified, 22 studies were included using data from tens of thousands of patients. This systematic review included 33 different models, of which 18 models were newly developed. Many studies showed a high risk of bias. The prognostic accuracy of models differed between 0.51 and 0.85. For most models, variables are readily available. Two models for mortality and one model for pulmonary complications have the potential to be developed further.

CONCLUSIONS

The availability of rigorous prediction models is limited. Several models are promising but need to be further developed. Some models provide information about risk factors for the development of complications. Performance status is a potential modifiable risk factor. None are ready for clinical implementation.

Essential risk factors for operative mortality in elderly esophageal cancer patients registered in the National Clinical Database of Japan

BACKGROUND

With the aging of society and increasingly longer of life expectancy, elderly patients with esophageal cancer are more commonly encountered. This study aimed to identify the risk factors for operative mortality after esophagectomy in elderly patients.

METHODS

We used data from the National Clinical Database of Japan. After cleaning the data, 10,633 records obtained from 861 hospitals were analyzed. A risk model for operative mortality was developed using risk factors from the entire study population. Then, odds ratios (OR) were compared between age categories using this risk model.

RESULTS

In this study, 1959 (18.4%) patients were ≥ 75 years (defined as "elderly" in this study). Eighteen variables, including T4b, N2-N3, and M1 in the TNM classification, were included in the risk model for operative mortality. The ORs increased in age categories < 65, 65-74, and ≥ 75 years for N2-N3 (1.172, 1.200, and 1.588, respectively), and M1 (2.189, 3.164, and 4.430, respectively). Based on these results, we also focused on residual tumors, which are caused by extensive tumor development. The operative mortality in the elderly group with residual tumors increased to more than twice than that in the non-elderly groups (15.9 vs. 5.5 or 6.5%) and was much higher than that in elderly patients without residual tumors (15.9 vs. 4.6%).

CONCLUSION

We should carefully select the treatment for elderly patients with highly advanced tumors, which result in N2-N3 and M1, to avoid unfavorable short-term outcomes. In addition, R0 resection is important in preventing operative mortality among elderly patients.

Ketorolac Administration After Colorectal Surgery Increases Anastomotic Leak Rate: A Meta-Analysis and Systematic Review

Objective

This meta-analysis aimed to evaluate whether ketorolac administration is associated with an increased anastomotic leak rate after colorectal surgery.

Methods

The literature was searched using the Web of Science, Embase, and PubMed databases, and the search ended on May 31, 2020. The Newcastle–Ottawa Scale was used to assess methodological quality. Statistical heterogeneity was assessed using the Chi-square Q test and I² statistics. Subgroup analysis was performed, and Egger's test was used to assess publication bias.

Results

This meta-analysis included seven studies with 400,822 patients. Our results demonstrated that ketorolac administration after surgery increases the risk of anastomotic leak [OR = 1.41, 95% CI: 0.81–2.49, Z = 1.21, P = 0.23]. Low heterogeneity was observed across these studies (I² = 0%, P = 0.51). The results of subgroup analysis showed that the use of ketorolac in case–control and retrospective cohort studies significantly increased the risk of anastomotic leak (P < 0.05). Furthermore, the subgroup analysis revealed that ketorolac use increased anastomotic leak rate in patients in the United States and Canada, and ketorolac plus morphine use did not increase anastomotic leak rate in Taiwanese patients (P < 0.05). No significant publication bias was observed (P = 0.126). Moreover, the analysis of risk factors related to anastomotic leak rate indicated that the total use of ketorolac did not increase the risk of anastomotic leak similar to the control group (P > 0.05).

Conclusion

The meta-analysis indicates that the use of ketorolac increases the risk of anastomotic leak after colorectal surgery.

Systematic Review Registration

PROSPERO, identifier CRD42020195724.

Influence of Damaged Stomach on Anastomotic Leakage following Cervical Esophagogastrostomy in Patients with Esophageal Cancer

BACKGROUND

Anastomotic leakage (AL) is one of the most common complications after esophagectomy. Although some patients have a history of peptic ulcers or other prior stomach diseases, the influence of a damaged stomach (DS) on AL incidence remains unclear. Therefore, we investigated the association between DS and incidence of AL in patients who underwent esophagectomy.

PATIENTS AND METHODS

Between 2015 and 2019, a total of 447 consecutive patients who underwent cervical esophagogastrostomy using gastric tube following esophagectomy were enrolled. DS was defined on the basis of endoscopic findings of ulcers or scars due to medical history or prior treatment. We compared the incidence of AL between patients with DS and those with a healthy stomach (HS). Univariate and multivariate logistic regression analyses were used to identify factors that could predict AL incidence.

RESULTS

Fifty-one patients (11.4%) had DS. Causes of DS included peptic ulcer (n = 36), endoscopic resection for early gastric cancer (n = 9), percutaneous endoscopic gastrostomies (n = 5), and post-chemotherapy scar for gastric malignant lymphoma (n = 1). Overall, AL occurred in 35 patients (7.8%). The incidence of AL in the DS group was significantly higher than in the HS group (15.7 vs. 6.8%, p = 0.03). DS was one of the independent predictive factors for AL (odds ratio, 2.75; 95% confidence interval, 1.10-6.92; p = 0.03) on multivariate analysis. Further, the diseases in the lower third of the conduit were associated with AL.

CONCLUSIONS

Presence of DS can predict AL in patients who underwent cervical esophagogastrostomy after esophagectomy.

Pneumonectomy for Lung Cancer Treatment in The Netherlands: Between-Hospital Variation and Outcomes

BACKGROUND

Pneumonectomy in lung cancer treatment is associated with considerable morbidity and mortality. Its use is reserved only for patients in whom a complete oncological resection by (sleeve) lobectomy is not possible. It is unclear whether a patients' risk of receiving a pneumonectomy is equally distributed. This study examined between-hospital variation of pneumonectomy use for primary lung cancer in the Netherlands.

METHODS

Data from the Dutch Lung Cancer Audit for Surgery from 2012 to 2016 were used to study the use of pneumonectomy for primary lung cancer in the Netherlands. Using multivariable logistic regression, factors associated with pneumonectomy use were identified and the expected number of pneumonectomies per hospital was determined. Subsequently, the observed/expected ratio (O/E ratio) per hospital was calculated to study between-hospital differences.

RESULTS

Of the 8446 included patients, 659 (7.8%) underwent a pneumonectomy with a mean postoperative mortality of 7.1% (n = 47). Factors associated with receiving a pneumonectomy were age, gender, cardiac and pulmonary comorbidities, tumor side, size and histopathology. The pneumonectomy use in the Netherlands varied considerably between hospitals (IQR 5.5-10.1%). Three hospitals out of 51 performed significantly less pneumonectomies than expected (O/E ratio < 0.5) and three significantly more (O/E ratio > 1.7). In the latter group, severe complications were more frequent, taking other influencing factors into account (OR 1.51, 95% CI 1.05-2.19).

CONCLUSIONS

There is a considerable between-hospital variation in pneumonectomy use in lung cancer treatment. To further optimize surgical lung cancer care, we suggest center-specific feedback on pneumonectomy use and the development of a risk-adjusted pneumonectomy indicator.

Effect of Case-Mix and Random Variation on Breast Cancer Care Quality Indicators and Their Rankability

OBJECTIVES

Hospital comparisons to improve quality of care require valid and reliable quality indicators. We aimed to test the validity and reliability of 6 breast cancer indicators by quantifying the influence of case-mix and random variation.

METHODS

The nationwide population-based database included 79 690 patients with breast cancer from 91 Dutch hospitals between 2011 and 2016. The indicator-scores calculated were: (1) irradical breast-conserving surgery (BCS) for invasive disease, (2) irradical BCS for ductal carcinoma-in-situ, (3) breast contour-preserving treatment, (4) magnetic resonance imaging (MRI) before neo-adjuvant chemotherapy, (5) radiotherapy for locally advanced disease, and (6) surgery within 5 weeks from diagnosis. Case-mix and random variation adjustments were performed by multivariable fixed and random effect logistic regression models. Rankability quantified the between-hospital variation, representing unexplained differences that might be the result of the level of quality of care, as low (<50%), moderate (50%-75%), or high (>75%).

RESULTS

All of the indicators showed between-hospital variation with wide (interquartile) ranges. Case-mix adjustment reduced variation in indicators 1 and 3 to 5. Random variation adjustment (further) reduced the variation for all indicators. Case-mix and random variation adjustments influenced the indicator-scores of individual hospitals and their ranking. Rankability was poor for indicator 1, 2, and 5, and moderate for 3, 4, and 6.

CONCLUSIONS

The 6 indicators lacked validity and/or reliability to a certain extent. Although measuring quality indicators may stimulate quality improvement in general, comparisons and judgments of individual hospital performance should be made with caution if based on indicators that have not been tested or adjusted for validity and reliability, especially in benchmarking.

From Multiple Quality Indicators of Breast Cancer Care Toward Hospital Variation of a Summary Measure

OBJECTIVES

To improve quality in breast cancer care, large numbers of quality indicators are collected per hospital, but benchmarking remains complex. We aimed to assess the validity of indicators, develop a textbook outcome summary measure, and compare case-mix adjusted hospital performance.

METHODS

From a nationwide population-based registry, all 79 690 nonmetastatic breast cancer patients surgically treated between 2011 and 2016 in 91 hospitals in The Netherlands were included. Twenty-one indicators were calculated and their construct validity tested by Spearman's rho. Between-hospital variation was expressed by interquartile range (IQR), and all valid indicators were included in the summary measure. Standardized scores (observed/expected based on case mix) were calculated as above (>100) or below (<100) expected. The textbook outcome was presented as a continuous and all-or-none score.

RESULTS

The size of between-hospital variation varied between indicators. Sixteen (76%) of 21 quality indicators showed construct validity, and 13 were included in the summary measure after excluding redundant indicators that showed collinearity with others owing to strong construct validity. The median all-or-none textbook outcome score was 49% (IQR 42%-54%) before and 49% (IQR 48%-51%) after case-mix adjustment. From the total of 91 hospitals, 3 hospitals were positive (3%) and 9 (10%) were negative outliers.

CONCLUSIONS

The textbook outcome summary measure showed discriminative ability when hospital performance was presented as an all-or-none score. Although indicator scores and outlier hospitals should always be interpreted cautiously, the summary measure presented here has the potential to improve Dutch breast cancer quality indicator efforts and could be implemented to further test its validity, feasibility, and usefulness.

Validation of the NUn score as a predictor of anastomotic leak and major complications after Esophagectomy

Predicting major anastomotic leak (AL) and major complications (Clavien-Dindo 3-5) following esophagectomy improves postoperative management of patients. The role of the NUn score in their prediction is controversial. This study aims to evaluate the predictive ability of this simple score. Data were retrospectively collected for consecutive esophagectomies over a 10-year period, and NUn scores were retrospectively calculated for each patient from informatics data. A standardized definition of major AL was used, excluding minor asymptomatic, radiologically detected leaks. The predictive accuracy of the NUn score and its constituent parts, for major AL and major complications, was assessed using area under receiver operating characteristics curves (AUROCs). Of 382 patients, 48 (13%) developed major AL and 123 (32%) developed major complications. The NUn score calculated on postoperative day 4 was significantly predictive of both outcomes, with AUROCs of 0.77 and 0.71, respectively (both P < 0.001). A NUn score cut-off of 10 had a negative predictive value of 95% for major AL. The NUn score was predictive of major complications on multivariable analysis. The NUn score was found to be a significant predictor of major AL, suggesting that this is a useful early warning score for major AL. The score may also be useful in identifying patients that are the most likely to benefit from enhanced recovery protocols.

Benchmark analyses in minimally invasive esophagectomy-impact on surgical quality improvement

Over the last decades, benchmarking has become an established management tool to improve quality in commercial economics. It is a rather new concept in the healthcare industry, and a confusingly wide range of approaches referring to "benchmarking" have been employed in the field of minimally invasive esophageal cancer surgery. It is our conviction that benchmarking will be an essential element of surgical research in the future. Therefore, defining and implementing standards is not only a desirable, but a vital step. Recently, we have introduced a standardized method of establishing valid benchmarks for surgical quality improvement including ideal outcome thresholds for total minimally invasive transthoracic esophagectomy (ttMIE). The present article aims at discussing the actual literature on benchmarking in minimally invasive esophagectomy (MIE) and at fueling the debate on how to further improve the current practice of surgical outcome research.

Ketorolac and Other NSAIDs Increase the Risk of Anastomotic Leakage After Surgery for GEJ Cancers: a Cohort Study of 557 Patients

OBJECTIVE

The objective of this study is to investigate the impact of ketorolac and other nonsteroidal anti-inflammatory drugs on anastomotic leakage after surgery for gastro-esophageal-junction cancer. Within the last two decades, the incidence of gastro-esophageal-junction cancer has increased in the western world and surgery is the curative treatment modality of choice. Anastomotic leakage is a feared complication of gastro-esophageal surgery, as it increases recurrence, morbidity, and mortality. Nonsteroidal anti-inflammatory drugs are widely used for postoperative pain relief. Nonsteroidal anti-inflammatory drugs have, however, in colorectal surgery, been shown to increase the risk of anastomotic leakage.

METHOD

In a historical cohort study, we investigated the impact of nonsteroidal anti-inflammatory drugs on anastomotic leakage in 557 patients undergoing surgery for gastro-esophageal-junction cancer. Data were collected from a prospective maintained database, the Danish National Patient Registry, and patient medical records. Data were analyzed using univariate and multivariate statistical models and were stratified for theoretical confounders.

RESULTS

In univariate analysis, we did not observe any difference in age, gender, tobacco exposure, or comorbidity status between patients experiencing anastomotic leakage and those without. In multivariate analysis, gender, histology, and type of anastomosis proved to affect odds ratios for anastomotic leakage. After adjustment for possible confounders, we found an odds ratio of 6.05 (95% confidence interval 2.71; 13.5) for ketorolac use and of 5.24 (95% confidence interval 1.85; 14.8) for use of other nonsteroidal anti-inflammatory drugs for anastomotic leakage during the first seven postoperative days.

CONCLUSION

In the present study, we found a strong association between the postoperative use of ketorolac and other nonsteroidal anti-inflammatory drugs and the risk for anastomotic leakage after surgery for gastro-esophageal-junction cancers.

Prediction models for patients with esophageal or gastric cancer: A systematic review and meta-analysis

Background

Clinical prediction models are increasingly used to predict outcomes such as survival in cancer patients. The aim of this study was threefold. First, to perform a systematic review to identify available clinical prediction models for patients with esophageal and/or gastric cancer. Second, to evaluate sources of bias in the included studies. Third, to investigate the predictive performance of the prediction models using meta-analysis.

Methods

MEDLINE, EMBASE, PsycINFO, CINAHL, and The Cochrane Library were searched for publications from the year 2000 onwards. Studies describing models predicting survival, adverse events and/or health-related quality of life (HRQoL) for esophageal or gastric cancer patients were included. Potential sources of bias were assessed and a meta-analysis, pooled per prediction model, was performed on the discriminative abilities (c-indices).

Results

A total of 61 studies were included (45 development and 16 validation studies), describing 47 prediction models. Most models predicted survival after a curative resection. Nearly 75% of the studies exhibited bias in at least 3 areas and model calibration was rarely reported. The meta-analysis showed that the averaged c-index of the models is fair (0.75) and ranges from 0.65 to 0.85.

Conclusion

Most available prediction models only focus on survival after a curative resection, which is only relevant to a limited patient population. Few models predicted adverse events after resection, and none focused on patient’s HRQoL, despite its relevance. Generally, the quality of reporting is poor and external model validation is limited. We conclude that there is a need for prediction models that better meet patients’ information needs, and provide information on both the benefits and harms of the various treatment options in terms of survival, adverse events and HRQoL.

The Effect of Neoadjuvant Chemoradiation on Anastomotic Leak and Additional 30-Day Morbidity and Mortality in Patients Undergoing Total Gastrectomy for Gastric Cancer

INTRODUCTION

In addition to increased perioperative morbidity, anastomotic leak following gastric resection for gastric cancer can have detrimental effects on overall and disease-free survival. The risk of anastomotic leak following neoadjuvant therapy remains unknown. The purpose of this study is to investigate the association of preoperative chemotherapy and radiation therapy with postoperative anastomotic leak and additional 30-day morbidity and mortality outcomes following total gastrectomy with reconstruction for gastric cancer using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP).

METHODS

Patients who underwent total gastrectomy with reconstruction for gastric cancer from 2005 to 2012 were identified. Within the NSQIP database, anastomotic leak is captured as an organ space infection. The association of preoperative chemotherapy and radiation therapy with anastomotic leak and additional 30-day morbidity and mortality outcomes was investigated using chi-squared analysis, Fisher's exact test, and Student's t test.

RESULTS

A total of 1135 patients met inclusion criteria; 121 (10.7%) patients underwent preoperative chemotherapy within 30 days of surgery, and 53 (4.7%) patients underwent preoperative radiation therapy within 90 days of surgery. Neither preoperative chemotherapy nor radiation therapy was associated with an increased risk of anastomotic leak (p = 0.12 and p = 0.58, respectively). When compared to patients who did not undergo neoadjuvant therapy, patients who underwent either preoperative chemotherapy or radiation therapy did not experience a higher frequency of 30-day mortality (p = 0.41), cardiac (p = 0.49), wound (p = 0.76), renal (p = 0.13), septic (p = 0.55), or venous thromboembolism (p = 0.19) events and were significantly less likely to experience a pulmonary event (p = 0.02).

CONCLUSION

Neoadjuvant therapy prior to gastric resection for gastric cancer is not associated with an increased risk of anastomotic leak or other additional short-term morbidity or mortality.

Significance of baseline FDG-PET/CT scan as a method of staging regional lymph nodes in patients with operable distal oesophageal or gastroesophageal junction adenocarcinoma

BACKGROUND

The new American Joint Committee on Cancer eighth edition (AJCC8) staging is the first to describe separate clinical and pathology staging systems, but still has low performance to predict prognosis in patients with oesophageal/gastroesophageal junction (O/GOJ) adenocarcinoma, who are candidates for surgery. Recent studies have demonstrated that O/GOJ cancer patients with 18F-fluorodeoxyglucose (FDG) avid regional lymph nodes (RLNs) may have poor prognosis. The aim of our study was to examine whether the baseline assessment of the FDG uptake of RLN improves the prognostic accuracy of the new AJCC8 staging.

PATIENTS AND METHODS

This single-centre retrospective study included patients with operable FDG avid O/GOJ adenocarcinoma treated with perioperative chemotherapy. All patients were reclassified according to the new AJCC8 clinical staging. Prognostic factors for time-to-progression (TTP) and overall survival (OS) were explored.

RESULTS

Of 430 patients included in the study, 180 (41.9%) had FDG avid RLN at baseline PET/CT scan before starting perioperative chemotherapy. The presence of FDG avid RLN was significantly and independently associated with shorter TTP and OS, especially in clinical stage III patients (p < .001 in both cases). Stage III patients with FDG avid RLN had similar TTP and OS to those with stage IVA. Classifying stage III patients with FDG avid RLN into stage IVA led to a significant improvement of the prognostic accuracy of the new AJCC8 clinical staging system (Harrell's concordance index improved from 0.555 to 0.588, p < .001). Of 430 patients starting perioperative chemotherapy, 332 underwent radical tumour resection. The presence of FDG avid RLN before starting perioperative chemotherapy could additionally predict a significantly shorter postoperative time-to-relapse and OS (p < .001 in both cases).

CONCLUSIONS

We propose that the incorporation of RLN status (by FDG PET/CT scan) into the AJCC8 staging system of O/GOJ adenocarcinoma improves its prognostic accuracy and may also improve treatment stratification.

External validation of the NUn score for predicting anastomotic leakage after oesophageal resection

Early detection of anastomotic leakage (AL) after oesophageal resection for malignancy is crucial. This retrospective study validates a risk score, predicting AL, which includes C-reactive protein, albumin and white cell count in patients undergoing oesophageal resection between 2003 and 2014. For validation of the NUn score a receiver operating characteristic (ROC) curve is estimated. Area under the ROC curve (AUC) is reported with 95% confidence interval (CI). Among 258 patients (79.5% male) 32 patients showed signs of anastomotic leakage (12.4%). NUn score in our data has a median of 9.3 (range 6.2–17.6). The odds ratio for AL was 1.31 (CI 1.03–1.67; p = 0.028). AUC for AL was 0.59 (CI 0.47–0.72). Using the original cutoff value of 10, the sensitivity was 45.2% an the specificity was 73.8%. This results in a positive predictive value of 19.4% and a negative predictive value of 90.6%. The proportion of variation in AL occurrence, which is explained by the NUn score, was 2.5% (PEV = 0.025). This study provides evidence for an external validation of a simple risk score for AL after oesophageal resection. In this cohort, the NUn score is not useful due to its poor discrimination.

In-hospital clinical outcomes after upper gastrointestinal surgery: Data from an international observational study

AIMS

Previous research suggests that patients undergoing upper gastrointestinal surgery are at high risk of poor postoperative outcomes. The aim of our study was to describe patient outcomes after elective upper gastrointestinal surgery at a global level.

METHODS

Prospective analysis of data collected during an international seven-day cohort study of 474 hospitals in 27 countries. Patients undergoing elective upper gastrointestinal surgery were recruited. Outcome measures were in-hospital complications and mortality at 30-days. Results are presented as n(%) and odds ratios with 95% confidence intervals.

RESULTS

2139 patients were included, of whom 498 (23.2%) developed one or more postoperative complications, with 30 deaths (1.4%). Patients with complications had longer median hospital stay 11 (6-18) days vs. 5 (2-10) days. Infectious complications were most frequent, affecting 368 (17.2%) patients. 328 (15.3%) patients were admitted to critical care postoperatively, of whom 161 (49.1%) developed a complication with 14 deaths (4.3%). In a multivariable logistic regression model we identified age (OR 1.02 [1.01-1.03]), American Society of Anesthesiologists physical status III (OR 2.12 [1.44-3.16]) and IV (OR 3.23 [1.72-6.09]), surgery for cancer (OR 1.63 [1.27-2.11]), open procedure (OR 1.40 [1.10-1.78]), intermediate surgery (OR 1.75 [1.12-2.81]) and major surgery (OR 2.65 [1.72-4.23]) as independent risk factors for postoperative complications. Patients undergoing major surgery for upper gastrointestinal cancer experienced twice the rate of complications compared to those undergoing other procedures (224/578 patients [38.8%] versus 274/1561 patients [17.6%]).

CONCLUSIONS

Complications and death are common after upper gastrointestinal surgery. Patients undergoing major surgery for cancer are at greatest risk.

Minimally invasive and open gallbladder cancer resections: 30- vs 90-day mortality

BACKGROUND

Minimally invasive surgery is increasingly used for gallbladder cancer resection. Postoperative mortality at 30 days is low, but 90-day mortality is underreported.

METHODS

Using National Cancer Database (1998-2012), all resection patients were included. Thirty- and 90-day mortality rates were compared.

RESULTS

A total of 36 067 patients were identified, 19 139 (53%) of whom underwent resection. Median age was 71 years and 70.7% were female. Ninety-day mortality following surgical resection was 2.3-fold higher than 30-mortality (17.1% vs 7.4%). There was a statistically significant increase in 30- and 90-day mortality with poorly differentiated tumors, presence of lymphovascular invasion, tumor stage, incomplete surgical resection and low-volume centers (P<0.001 for all). Even for the 1885 patients who underwent minimally invasive resection between 2010 and 2012, the 90-day mortality was 2.8-fold higher than the 30-day mortality (12.0% vs 4.3%).

CONCLUSIONS

Ninety-day mortality following gallbladder cancer resection is significantly higher than 30-day mortality. Postoperative mortality is associated with tumor grade, lymphovascular invasion, tumor stage, type and completeness of surgical resection as well as type and volume of facility.

Adjusted Hospital Outcomes of Abdominal Aortic Aneurysm Surgery Reported in the Dutch Surgical Aneurysm Audit

OBJECTIVE/BACKGROUND

The Dutch Surgical Aneurysm Audit (DSAA) is mandatory for all patients with primary abdominal aortic aneurysms (AAAs) in the Netherlands. The aims are to present the observed outcomes of AAA surgery against the predicted outcomes by means of V-POSSUM (Vascular-Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity). Adjusted mortality was calculated by the original and re-estimated V(physiology)-POSSUM for hospital comparisons.

METHODS

All patients operated on from January 2013 to December 2014 were included for analysis. Calibration and discrimination of V-POSSUM and V(p)-POSSUM was analysed. Mortality was benchmarked by means of the original V(p)-POSSUM formula and risk-adjusted by the re-estimated V(p)-POSSUM on the DSAA.

RESULTS

In total, 5898 patients were included for analysis: 4579 with elective AAA (EAAA) and 1319 with acute abdominal aortic aneurysm (AAAA), acute symptomatic (SAAA; n = 371) or ruptured (RAAA; n = 948). The percentage of endovascular aneurysm repair (EVAR) varied between hospitals but showed no relation to hospital volume (EAAA: p = .12; AAAA: p = .07). EAAA, SAAA, and RAAA mortality was, respectively, 1.9%, 7.5%, and 28.7%. Elective mortality was 0.9% after EVAR and 5.0% after open surgical repair versus 15.6% and 27.4%, respectively, after AAAA. V-POSSUM overestimated mortality in most EAAA risk groups (p < .01). The discriminative ability of V-POSSUM in EAAA was moderate (C-statistic: .719) and poor for V(p)-POSSUM (C-statistic: .665). V-POSSUM in AAAA repair overestimated in high risk groups, and underestimated in low risk groups (p < .01). The discriminative ability in AAAA of V-POSSUM was moderate (.713) and of V(p)-POSSUM poor (.688). Risk adjustment by the re-estimated V(p)-POSSUM did not have any effect on hospital variation in EAAA but did in AAAA.

CONCLUSION

Mortality in the DSAA was in line with the literature but is not discriminative for hospital comparisons in EAAA. Adjusting for V(p)-POSSUM, revealed no association between hospital volume and treatment or outcome. Risk adjustment for case mix by V(p)-POSSUM in patients with AAAA has been shown to be important.

Quantitative Shotgun Proteomics Unveils Candidate Novel Esophageal Adenocarcinoma (EAC)-specific Proteins

Esophageal cancer is the eighth most common cancer worldwide and the majority of patients have systemic disease at presentation. Esophageal adenocarcinoma (OAC), the predominant subtype in western countries, is largely resistant to current chemotherapy regimens. Selective markers are needed to enhance clinical staging and to allow targeted therapies yet there are minimal proteomic data on this cancer type. After histological review, lysates from OAC and matched normal esophageal and gastric samples from seven patients were subjected to LC MS/MS after tandem mass tag labeling and OFFGEL fractionation. Patient matched samples of OAC, normal esophagus, normal stomach, lymph node metastases and uninvolved lymph nodes were used from an additional 115 patients for verification of expression by immunohistochemistry (IHC).

Over six thousand proteins were identified and quantified across samples. Quantitative reproducibility was excellent between technical replicates and a moderate correlation was seen across samples with the same histology. The quantitative accuracy was verified across the dynamic range for seven proteins by immunohistochemistry (IHC) on the originating tissues. Multiple novel tumor-specific candidates are proposed and EPCAM was verified by IHC.

This shotgun proteomic study of OAC used a comparative quantitative approach to reveal proteins highly expressed in specific tissue types. Novel tumor-specific proteins are proposed and EPCAM was demonstrated to be specifically overexpressed in primary tumors and lymph node metastases compared with surrounding normal tissues. This candidate and others proposed in this study could be developed as tumor-specific targets for novel clinical staging and therapeutic approaches.