A first-in-class pan-lysyl oxidase inhibitor impairs stromal remodeling and enhances gemcitabine response and survival in pancreatic cancer

The lysyl oxidase family represents a promising target in stromal targeting of solid tumors due to the importance of this family in crosslinking and stabilizing fibrillar collagens and its known role in tumor desmoplasia. Using small-molecule drug-design approaches, we generated and validated PXS-5505, a first-in-class highly selective and potent pan-lysyl oxidase inhibitor. We demonstrate in vitro and in vivo that pan-lysyl oxidase inhibition decreases chemotherapy-induced pancreatic tumor desmoplasia and stiffness, reduces cancer cell invasion and metastasis, improves tumor perfusion and enhances the efficacy of chemotherapy in the autochthonous genetically engineered KPC model, while also demonstrating antifibrotic effects in human patient-derived xenograft models of pancreatic cancer. PXS-5505 is orally bioavailable, safe and effective at inhibiting lysyl oxidase activity in tissues. Our findings present the rationale for progression of a pan-lysyl oxidase inhibitor aimed at eliciting a reduction in stromal matrix to potentiate chemotherapy in pancreatic ductal adenocarcinoma.

Practice variation in anastomotic leak after esophagectomy: Unravelling differences in failure to rescue

INTRODUCTION

Failure to rescue (FTR) is an important outcome measure after esophagectomy and reflects mortality after postoperative complications. Differences in FTR have been associated with hospital resection volume. However, insight into how centers manage complications and achieve their outcomes is lacking. Anastomotic leak (AL) is a main contributor to FTR. This study aimed to assess differences in FTR after AL between centers, and to identify factors that explain these differences.

METHODS

TENTACLE - Esophagus is a multicenter, retrospective cohort study, which included 1509 patients with AL after esophagectomy. Differences in FTR were assessed between low-volume (<20 resections), middle-volume (20-60 resections) and high-volume centers (≥60 resections). Mediation analysis was performed using logistic regression, including possible mediators for FTR: case-mix, hospital resources, leak severity and treatment.

RESULTS

FTR after AL was 11.7%. After adjustment for confounders, FTR was lower in high-volume vs. low-volume (OR 0.44, 95%CI 0.2-0.8), but not versus middle-volume centers (OR 0.67, 95%CI 0.5-1.0). After mediation analysis, differences in FTR were found to be explained by lower leak severity, lower secondary ICU readmission rate and higher availability of therapeutic modalities in high-volume centers. No statistically significant direct effect of hospital volume was found: high-volume vs. low-volume 0.86 (95%CI 0.4-1.7), high-volume vs. middle-volume OR 0.86 (95%CI 0.5-1.4).

CONCLUSION

Lower FTR in high-volume compared with low-volume centers was explained by lower leak severity, less secondary ICU readmissions and higher availability of therapeutic modalities. To reduce FTR after AL, future studies should investigate effective strategies to reduce leak severity and prevent secondary ICU readmission.

Laparoscopic fundoplication performed in community hospital settings: A protocol for systematic review

BACKGROUND

Laparoscopic fundoplication (LF) is well-established as the surgical intervention of choice for management of refactory gastro-esophageal reflux disease. Much of its success lies in the reported benefits in symptom control outlined by the postoperative patient. It is unclear whether patient-reported outcomes differ according to the institution type providing care. This review aimed to address this knowledge gap by reviewing the available evidence examining patient-reported outcomes of LF in non-metropolitan centers.

OBJECTIVES

To investigate patient-reported outcomes of LF performed in regional or community-based hospitals.

DATA SOURCES

Four electronic databases, and citations of relevant articles.

STUDY ELIGIBILITY CRITERIA

Only studies that separately reported patient-reported outcomes of LF performed in regional or community hospitals were included; papers deemed to be unclear about the type of facility in which LF surgeries were performed, or in which data from LF surgeries performed in regional/community hospitals was combined with data from major metropolitan hospitals, were excluded.

STUDY APPRAISAL

Only studies that were graded as fair or good using Quality Assessment Tool for Observational Cohort and Cross-sectional studies were eligible for inclusion in this review. Seven studies were then eligible for inclusion, all of which were observational cohort studies with 6 of the studies reporting on a single intervention arm.

RESULTS

Seven observational cohort studies were included in the review, with a combined total of 1071 patients who underwent LF at non-metropolitan centers. Of these, data was collected for 742 patients, yielding an overall response rate of 69.3%. All 7 studies assessed patients' post-operative outcomes through questionnaires that were based on a modified Likert scale or a similar tool. Overall patient satisfaction was high (86%) and a significant majority of patients stated they would recommend the procedure to others (93.3%). Post-operative prevalence of reflux and dysphagia compared favorably to rates generally reported in the literature (11.9% and 17.6% respectively). Further research is required to ascertain the safety of performing these procedures in non-metropolitan hospitals.

CONCLUSION

Current evidence suggests that patient-reported outcomes are favorable for patients undergoing LF in community settings, and are broadly comparable to those undergoing LF in tertiary-level centers.

Management of acute appendicitis during the COVID-19 pandemic: a retrospective cohort study

BACKGROUND

The Coronavirus Disease 2019 (COVID-19) pandemic profoundly impacted delivery of health care. South Western Sydney Local Health District (SWSLHD) experienced some of the highest cases, admissions and deaths during the Delta and Omicron waves in New South Wales. This study aims to determine the impact of the pandemic on emergency surgery services for adults presenting with acute appendicitis.

METHODS

A retrospective review of patient records was performed of adults presenting with acute appendicitis between 1st March 2021 and 31st March 2022, which was compared to a pre-COVID control period of the same dates in 2019-2020. Patients managed operatively or conservatively were included.

RESULTS

1556 patients were included in the operative arm; 723 and 833 respectively in the study and control groups, which were comparable at baseline. 1.66% were COVID positive. During the pandemic, patients were significantly more likely to be investigated with computered tomography (CT) scan (p ≤ 0.001), present with complicated appendicitis (p = 0.03), and require caecectomy (p = 0.005). They had higher American Society of Anaesthesiology (ASA) scores (p = 0.001) and significantly lower negative appendectomy rates (p = 0.001). Fifty-two patients were included in the conservative arm; 29 and 23 respectively in the pandemic and control groups. Patients were comparable at baseline. There were two COVID positive patients. During the pandemic, there was a significant reduction in complications (p = 0.033), readmissions (0.044) and interval appendicectomy (p = 0.0044).

CONCLUSION

We identified higher rates of complicated appendicitis, caecectomies and greater reliance on CT imaging preoperatively during the pandemic in SWSLHD.

Elective surgery system strengthening: development, measurement, and validation of the surgical preparedness index across 1632 hospitals in 119 countries

BACKGROUND

The 2015 Lancet Commission on global surgery identified surgery and anaesthesia as indispensable parts of holistic health-care systems. However, COVID-19 exposed the fragility of planned surgical services around the world, which have also been neglected in pandemic recovery planning. This study aimed to develop and validate a novel index to support local elective surgical system strengthening and address growing backlogs.

METHODS

First, we performed an international consultation through a four-stage consensus process to develop a multidomain index for hospital-level assessment (surgical preparedness index; SPI). Second, we measured surgical preparedness across a global network of hospitals in high-income countries (HICs), middle-income countries (MICs), and low-income countries (LICs) to explore the distribution of the SPI at national, subnational, and hospital levels. Finally, using COVID-19 as an example of an external system shock, we compared hospitals' SPI to their planned surgical volume ratio (SVR; ie, operations for which the decision for surgery was made before hospital admission), calculated as the ratio of the observed surgical volume over a 1-month assessment period between June 6 and Aug 5, 2021, against the expected surgical volume based on hospital administrative data from the same period in 2019 (ie, a pre-pandemic baseline). A linear mixed-effects regression model was used to determine the effect of increasing SPI score.

FINDINGS

In the first phase, from a longlist of 103 candidate indicators, 23 were prioritised as core indicators of elective surgical system preparedness by 69 clinicians (23 [33%] women; 46 [67%] men; 41 from HICs, 22 from MICs, and six from LICs) from 32 countries. The multidomain SPI included 11 indicators on facilities and consumables, two on staffing, two on prioritisation, and eight on systems. Hospitals were scored from 23 (least prepared) to 115 points (most prepared). In the second phase, surgical preparedness was measured in 1632 hospitals by 4714 clinicians from 119 countries. 745 (45·6%) of 1632 hospitals were in MICs or LICs. The mean SPI score was 84·5 (95% CI 84·1-84·9), which varied between HIC (88·5 [89·0-88·0]), MIC (81·8 [82·5-81·1]), and LIC (66·8 [64·9-68·7]) settings. In the third phase, 1217 (74·6%) hospitals did not maintain their expected SVR during the COVID-19 pandemic, of which 625 (51·4%) were from HIC, 538 (44·2%) from MIC, and 54 (4·4%) from LIC settings. In the mixed-effects model, a 10-point increase in SPI corresponded to a 3·6% (95% CI 3·0-4·1; p<0·0001) increase in SVR. This was consistent in HIC (4·8% [4·1-5·5]; p<0·0001), MIC (2·8 [2·0-3·7]; p<0·0001), and LIC (3·8 [1·3-6·7%]; p<0·0001) settings.

INTERPRETATION

The SPI contains 23 indicators that are globally applicable, relevant across different system stressors, vary at a subnational level, and are collectable by front-line teams. In the case study of COVID-19, a higher SPI was associated with an increased planned surgical volume ratio independent of country income status, COVID-19 burden, and hospital type. Hospitals should perform annual self-assessment of their surgical preparedness to identify areas that can be improved, create resilience in local surgical systems, and upscale capacity to address elective surgery backlogs.

FUNDING

National Institute for Health Research (NIHR) Global Health Research Unit on Global Surgery, NIHR Academy, Association of Coloproctology of Great Britain and Ireland, Bowel Research UK, British Association of Surgical Oncology, British Gynaecological Cancer Society, and Medtronic.

Prognostic models to predict survival in patients with pancreatic cancer: a systematic review

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) has poor survival. Current treatments offer little likelihood of cure or long-term survival. This systematic review evaluates prognostic models predicting overall survival in patients diagnosed with PDAC.

METHODS

We conducted a comprehensive search of eight electronic databases from their date of inception through to December 2019. Studies that published models predicting survival in patients with PDAC were identified.

RESULTS

3297 studies were identified; 187 full-text articles were retrieved and 54 studies of 49 unique prognostic models were included. Of these, 28 (57.1%) were conducted in patients with advanced disease, 17 (34.7%) with resectable disease, and four (8.2%) in all patients. 34 (69.4%) models were validated, and 35 (71.4%) reported model discrimination, with only five models reporting values >0.70 in both derivation and validation cohorts. Many (n = 27) had a moderate to high risk of bias and most (n = 33) were developed using retrospective data. No variables were unanimously found to be predictive of survival when included in more than one study.

CONCLUSION

Most prognostic models were developed using retrospective data and performed poorly. Future research should validate instruments performing well locally in international cohorts and investigate other potential predictors of survival.

International variation in oesophageal and gastric cancer survival 2012-2014: differences by histological subtype and stage at diagnosis (an ICBP SURVMARK-2 population-based study)

OBJECTIVE

To provide the first international comparison of oesophageal and gastric cancer survival by stage at diagnosis and histological subtype across high-income countries with similar access to healthcare.

METHODS

As part of the ICBP SURVMARK-2 project, data from 28 923 patients with oesophageal cancer and 25 946 patients with gastric cancer diagnosed during 2012-2014 from 14 cancer registries in seven countries (Australia, Canada, Denmark, Ireland, New Zealand, Norway and the UK) were included. 1-year and 3-year age-standardised net survival were estimated by stage at diagnosis, histological subtype (oesophageal adenocarcinoma (OAC) and oesophageal squamous cell carcinoma (OSCC)) and country.

RESULTS

Oesophageal cancer survival was highest in Ireland and lowest in Canada at 1 (50.3% vs 41.3%, respectively) and 3 years (27.0% vs 19.2%) postdiagnosis. Survival from gastric cancer was highest in Australia and lowest in the UK, for both 1-year (55.2% vs 44.8%, respectively) and 3-year survival (33.7% vs 22.3%). Most patients with oesophageal and gastric cancer had regional or distant disease, with proportions ranging between 56% and 90% across countries. Stage-specific analyses showed that variation between countries was greatest for localised disease, where survival ranged between 66.6% in Australia and 83.2% in the UK for oesophageal cancer and between 75.5% in Australia and 94.3% in New Zealand for gastric cancer at 1-year postdiagnosis. While survival for OAC was generally higher than that for OSCC, disparities across countries were similar for both histological subtypes.

CONCLUSION

Survival from oesophageal and gastric cancer varies across high-income countries including within stage groups, particularly for localised disease. Disparities can partly be explained by earlier diagnosis resulting in more favourable stage distributions, and distributions of histological subtypes of oesophageal cancer across countries. Yet, differences in treatment, and also in cancer registration practice and the use of different staging methods and systems, across countries may have impacted the comparisons. While primary prevention remains key, advancements in early detection research are promising and will likely allow for additional risk stratification and survival improvements in the future.

Loop and drain technique for prevention of surgical site infection in upper gastrointestinal surgery

INTRODUCTION

Hepatobiliary and pancreatic surgery is frequently complicated by surgical site infections (SSI) with significant postoperative morbidity and mortality rates contributing to the economic burden on healthcare. Advancements in operative techniques to prevent SSI are gaining traction in clinical practice. This study compares the effectiveness of the 'loop and drain technique (LDT)', a combination method utilizing a continuous subcutaneous vessel loop and subcuticular suture for surgical wound closure in patients undergoing upper gastrointestinal surgery at a Metropolitan Hospital in Sydney.

METHODS

A retrospective review of patients who underwent an upper gastrointestinal procedure was conducted at Bankstown-Lidcombe hospital between 2017 and 2019. There were 77 patients in the LDT group and 123 patients included in the control group. The primary outcome assessed was the rate of SSI. Secondary outcomes included length of stay (LOS) and drainage of surgical site infections.

RESULT

Two hundred adult patients were treated for an upper gastrointestinal procedure. The most common operation was a Whipple procedure (35.0%). The rate of SSI was 12.5% with all these patients receiving intravenous antibiotics. The LDT cohort had a significantly lower rate of SSI compared to their counterparts (3.9% vs. 17.9%, P = 0.004).

CONCLUSION

The LDT method is associated with a decreased incidence of SSI and should be considered as a cost-effective operative technique to improve patient outcomes after upper gastrointestinal surgery.