Australasian Malignant PLeural Effusion (AMPLE)-4 trial: study protocol for a multi-centre randomised trial of topical antibiotics prophylaxis for infections of indwelling pleural catheters.

BACKGROUND: Malignant pleural effusion (MPE) is a debilitating condition as it commonly causes disabling breathlessness and impairs quality of life (QoL). Indwelling pleural catheter (IPC) offers an effective alternative for the management of MPE. However, IPC-related infections remain a significant concern and there are currently no long-term strategies for their prevention. The Australasian Malignant PLeural Effusion (AMPLE)-4 trial is a multicentre randomised trial that evaluates the use of topical mupirocin prophylaxis (vs no mupirocin) to reduce catheter-related infections in patients with MPE treated with an IPC. METHODS: A pragmatic, multi-centre, open-labelled, randomised trial. Eligible patients with MPE and an IPC will be randomised 1:1 to either regular topical mupirocin prophylaxis or no mupirocin (standard care). For the interventional arm, topical mupirocin will be applied around the IPC exit-site after each drainage, at least twice weekly. Weekly follow-up via phone calls or in person will be conducted for up to 6 months. The primary outcome is the percentage of patients who develop an IPC-related (pleural, skin, or tract) infection between the time of catheter insertion and end of follow-up period. Secondary outcomes include analyses of infection (types and episodes), hospitalisation days, health economics, adverse events, and survival. Subject to interim analyses, the trial will recruit up to 418 participants. DISCUSSION: Results from this trial will determine the efficacy of mupirocin prophylaxis in patients who require IPC for MPE. It will provide data on infection rates, microbiology, and potentially infection pathways associated with IPC-related infections. ETHICS AND DISSEMINATION: Sir Charles Gairdner and Osborne Park Health Care Group Human Research Ethics Committee has approved the study (RGS0000005920). Results will be published in peer-reviewed journals and presented at scientific conferences. TRIAL REGISTRATION: Australia New Zealand Clinical Trial Registry ACTRN12623000253606. Registered on 9 March 2023.

Early Video-assisted Thoracoscopic Surgery or Intrapleural Enzyme Therapy in Pleural Infection: A Feasibility Randomized Controlled Trial. The Third Multicenter Intrapleural Sepsis Trial-MIST-3.

Rationale: Assessing the early use of video-assisted thoracoscopic surgery (VATS) or intrapleural enzyme therapy (IET) in pleural infection requires a phase III randomized controlled trial (RCT). Objectives: To establish the feasibility of randomization in a surgery-versus-nonsurgery trial as well as the key outcome measures that are important to identify relevant patient-centered outcomes in a subsequent RCT. Methods: The MIST-3 (third Multicenter Intrapleural Sepsis Trial) was a prospective multicenter RCT involving eight U.K. centers combining on-site and off-site surgical services. The study enrolled all patients with a confirmed diagnosis of pleural infection and randomized those with ongoing pleural sepsis after an initial period (as long as 24 h) of standard care to one of three treatment arms: continued standard care, early IET, or a surgical opinion with regard to early VATS. The primary outcome was feasibility based on >50% of eligible patients being successfully randomized, >95% of randomized participants retained to discharge, and >80% of randomized participants retained to 2 weeks of follow-up. The analysis was performed per intention to treat. Measurements and Main Results: Of 97 eligible patients, 60 (62%) were randomized, with 100% retained to discharge and 84% retained to 2 weeks. Baseline demographic, clinical, and microbiological characteristics of the patients were similar across groups. Median times to intervention were 1.0 and 3.5 days in the IET and surgery groups, respectively (P = 0.02). Despite the difference in time to intervention, length of stay (from randomization to discharge) was similar in both intervention arms (7 d) compared with standard care (10 d) (P = 0.70). There were no significant intergroup differences in 2-month readmission and further intervention, although the study was not adequately powered for this outcome. Compared with VATS, IET demonstrated a larger improvement in mean EuroQol five-dimension health utility index (five-level edition) from baseline (0.35) to 2 months (0.83) (P = 0.023). One serious adverse event was reported in the VATS arm. Conclusions: This is the first multicenter RCT of early IET versus early surgery in pleural infection. Despite the logistical challenges posed by the coronavirus disease (COVID-19) pandemic, the study met its predefined feasibility criteria, demonstrated potential shortening of length of stay with early surgery, and signals toward earlier resolution of pain and a shortened recovery with IET. The study findings suggest that a definitive phase III study is feasible but highlights important considerations and significant modifications to the design that would be required to adequately assess optimal initial management in pleural infection.The trial was registered on ISRCTN (number 18,192,121).

Achieving Molecular Profiling in Pleural Biopsies: A Multicenter, Retrospective Cohort Study.

BACKGROUND: Pleural biopsy findings offer greater diagnostic sensitivity in malignant pleural effusions compared with pleural fluid. The adequacy of pleural biopsy techniques in achieving molecular marker status has not been studied, and such information (termed "actionable" histology) is critical in providing a rational, efficient, and evidence-based approach to diagnostic investigation. RESEARCH QUESTION: What is the adequacy of various pleural biopsy techniques at providing adequate molecular diagnostic information to guide treatment in malignant pleural effusions? STUDY DESIGN AND METHODS: This study analyzed anonymized data on 183 patients from four sites across three countries in whom pleural biopsy results had confirmed a malignant diagnosis and molecular profiling was relevant for the diagnosed cancer type. The primary outcome measure was adequacy of pleural biopsy for achieving molecular marker status. Secondary outcomes included clinical factors predictive of achieving a molecular diagnosis. RESULTS: The median age of patients was 71 years (interquartile range, 63-78 years), with 92 of 183 (50%) male. Of the 183 procedures, 105 (57%) were local anesthetic thoracoscopies (LAT), 12 (7%) were CT scan guided, and 66 (36%) were ultrasound guided. Successful molecular marker analysis was associated with mode of biopsy, with LAT having the highest yield and ultrasound-guided biopsy the lowest (LAT vs CT scan guided vs ultrasound guided: LAT yield, 95%; CT scan guided, 86%; and ultrasound guided, 77% [P = .004]). Biopsy technique and size of biopsy sample were independently associated with successful molecular marker analysis. LAT had an adjusted OR for successful diagnosis of 30.16 (95% CI, 3.15-288.56; P = .003) and biopsy sample size an OR of 1.18 (95% CI, 1.02-1.37) per millimeter increase in tissue sample size (P < .03). INTERPRETATION: Although previous studies have shown comparable overall diagnostic yields, in the modern era of targeted therapies, this study found that LAT offers far superior results to image-guided techniques at achieving molecular profiling and remains the optimal diagnostic tool.

Objective Thoracoscopic Criteria in Differentiation between Benign and Malignant Pleural Effusions.

BACKGROUND: Thoracoscopy is the "gold standard" diagnostic modality for investigation of suspected pleural malignancy. It is postulated that meticulous assessment of the pleural cavity may be adequate to indicate malignancy through the macroscopic findings of nodules, pleural thickening, and lymphangitis. We attempted to critically assess this practice, by precisely defining objective macroscopic criteria which might differentiate benign from malignant pleural diseases according to intrapleural pattern and anatomical location, and thereby to explore the predilection of abnormalities to specific sites on pleural surfaces. METHODS: A structured review of recorded video footage from medical thoracoscopy procedures in 96 patients was conducted by 2 independent assessors. Abnormalities were scored on agreed, objective criteria for the presence of nodules, lymphangitis and inflammation on each of the costoparietal, visceral and diaphragmatic surfaces. The costoparietal pleura was divided into 6 levels (apical, middle, and inferior surfaces of the lateral and posterior parietal pleura). The anterior surface of the costoparietal pleura was excluded from analysis after interim review as this surface was rarely seen. RESULTS: In the benign group, inflammation was the predominant finding in 65% (n = 33; costoparietal), 44% (n = 21; visceral), and 42% (n = 15; diaphragmatic). Nodules were detected in 24% (n = 12; costoparietal), 8% (n = 4; visceral), and 8% (n = 3; diaphragmatic). The most affected surfaces with inflammation were the middle lateral (60%) and the inferior lateral (57.8%) parts of the costoparietal pleura. In the malignant group, nodules were the predominant finding according to surface in 73% (n = 33; costoparietal), 32% (n = 13; visceral) and 48% (n = 17; diaphragmatic). Inflammation was detected in 44% (n = 20; costoparietal), 25% (n = 10; visceral), and 29% (n = 10; diaphragmatic). The most affected surfaces with nodules were the middle lateral (67.4%) and inferior lateral (66.7%) costoparietal pleural surfaces. CONCLUSION: This is the first detailed, anatomical description of abnormalities in the pleural space during thoracoscopy. While nodules were the predominant pattern in malignant pleural effusion, they were detected in 24% of benign diagnoses. Detection of nodules in >1 area of the costoparietal pleura was in favor of a malignant diagnosis. Inflammation was the predominant pattern in benign pleural effusion. Our results suggest that macroscopic nodules in malignant diagnoses have a predilection for the middle and inferior surfaces of the lateral costoparietal pleura.

Update on biology and management of mesothelioma.

Malignant pleural mesothelioma is an aggressive, incurable cancer that is usually caused by asbestos exposure several decades before symptoms arise. Despite widespread prohibition of asbestos production and supply, its incidence continues to increase. It is heterogeneous in its presentation and behaviour, and diagnosis can be notoriously difficult. Identification of actionable gene mutations has proven challenging and current treatment options are largely ineffective, with a median survival of 10-12 months.However, the past few years have witnessed major advances in our understanding of the biology and pathogenesis of mesothelioma. This has also revealed the limitations of existing diagnostic algorithms and identified new treatment targets.Recent clinical trials have re-examined the role of surgery, provided new options for the management of associated pleural effusions and heralded the addition of targeted therapies. The increasing complexity of mesothelioma management, along with a desperate need for further research, means that a multidisciplinary team framework is essential for the delivery of contemporary mesothelioma care.This review provides a synthesised overview of the current state of knowledge and an update on the latest research in the field.

Critical analysis of the utility of initial pleural aspiration in the diagnosis and management of suspected malignant pleural effusion.

INTRODUCTION: Current guidelines recommend an initial pleural aspiration in the investigation and management of suspected malignant pleural effusions (MPEs) with the aim of establishing a diagnosis, identifying non-expansile lung (NEL) and, at times, providing a therapeutic procedure. A wealth of research has been published since the guidelines suggesting that results and outcomes from an aspiration may not always provide sufficient information to guide management. It is important to establish the validity of these findings in a 'real world' population. METHODS: A retrospective analysis was conducted of all patients who underwent pleural fluid (PF) sampling, in a single centre, over 3 years to determine the utility of the initial aspiration. RESULTS: A diagnosis of MPE was confirmed in 230/998 (23%) cases, a further 95/998 (9.5%) were presumed to represent MPE. Transudative biochemistry was found in 3% of cases of confirmed MPE. Positive PF cytology was only sufficient to guide management in 45/140 (32%) cases. Evidence of pleural thickening on CT was associated with both negative cytology (χ2 1df=26.27, p<0.001) and insufficient samples (χ2 1df=10.39, p=0.001). In NEL 44.4% of patients did not require further procedures after pleurodesis compared with 72.7% of those with expansile lung (χ2 1df=5.49, p=0.019). In patients who required a combined diagnostic and therapeutic aspiration 106/113 (93.8%) required further pleural procedures. CONCLUSIONS: An initial pleural aspiration does not achieve either definitive diagnosis or therapy in the majority of patients. A new pathway prioritising symptom management while reducing procedures should be considered.

Patient-derived malignant pleural mesothelioma cell cultures: a tool to advance biomarker-driven treatments.

Malignant pleural mesothelioma (MPM) is an aggressive cancer, associated with poor prognosis. We assessed the feasibility of patient-derived cell cultures to serve as an ex vivo model of MPM. Patient-derived MPM cell cultures (n=16) exhibited stemness features and reflected intratumour and interpatient heterogeneity. A subset of the cells were subjected to high-throughput drug screening and coculture assays with cancer-specific cytotoxic T cells and showed diverse responses. Some of the biphasic MPM cells were capable of processing and presenting the neoantigen SSX-2 endogenously. In conclusion, patient-derived MPM cell cultures are a promising and faithful ex vivo model of MPM.

Multidisciplinary approaches to the management of malignant pleural effusions: a guide for the clinician.

INTRODUCTION: Malignant pleural effusion (MPE) is a complication of advanced cancer, associated with significant mortality and morbidity. This entity is commonly treated by respiratory physicians, oncologists, and thoracic surgeons. There have been various randomized clinical trials assessing the relative merits of chest drain pleurodesis, indwelling pleural catheters, treatment of septated MPEs, the use of thoracoscopy and pleurodesis and pleurodesis through IPCs in the past decade which have addressed some key areas in the management of MPEs, with an increasing focus on patient related outcome. AREAS COVERED: In this review, we examine and review the literature for management strategies for MPEs and discuss future directions. A detailed search of scientific literature and clinical trial registries published in the past two decades was undertaken. EXPERT OPINION: Tremendous progress has been made in management of MPE in the past decade and current strategy involves patient preference along with local expertise that is available.