Malignant pleural effusion (MPE) is a common complication of thoracic and extrathoracic malignancies and is associated with high mortality and elevated costs to healthcare systems. Over the last decades the understanding of pathophysiology mechanisms, diagnostic techniques and optimal treatment intervention in MPE have been greatly advanced by recent high-quality research, leading to an ever less invasive diagnostic approach and more personalized management. Despite a number of management options, including talc pleurodesis, indwelling pleural catheters and combinations of the two, treatment for MPE remains symptom directed and centered around drainage strategy. In the next future, because of a better understanding of underlying tumor biology together with more sensitive molecular diagnostic techniques, it is likely that combined diagnostic and therapeutic procedures allowing near total outpatient management of MPE will become popular. This article provides a review of the current advances, new discoveries and future directions in the pathophysiology, diagnosis and management of MPE.

Background: Diagnostic yield (DY) and safety of computed tomography (CT)- and thoracic ultrasound (TUS)-guided biopsies in the diagnosis of pleural lesions have been investigated in a number of studies, but no synthesis of data from the literature has ever been performed. Objectives: We aimed to provide the first systematic review and meta-analysis on the DY and safety of CT- versus TUS-guided biopsy in the diagnosis of pleural lesions. Method: We searched MEDLINE and EMBASE for all studies reporting outcomes of interest published up to April 2018. Two authors reviewed all titles/abstracts and retrieved selected full text to identify studies according to predefined selection criteria. Summary estimates were derived using the random-effects model. Cumulative meta-analysis assessed the influence of increasing adoption of the procedures over time. Results: Thirty original studies were included in the present review; the number of studies on TUS-guided biopsy was almost three-fold higher than those on CT-guided biopsy. The pooled DYs of the 2 procedures were overall excellent and differed <10%, being 84% for TUS-guided biopsy and 93% for CT-guided biopsy. Safety profiles were reassuring for both the techniques, being 7 and 3% for CT- and TUS-guided biopsy, respectively. DY of ultrasound technique significantly improved over time, while no time effect was observed for CT-guided biopsy. Conclusions: Data show that CT- and TUS-guided biopsies in the diagnosis of pleural lesions are both excellent procedures, without meaningful differences in DYs and safety. Considering that TUS is non-ionizing and easily performed at the bedside, it should be the preferred approach in presence of adequate skills.

The incidence of non-malignant pleural effusions far outweighs that of malignant pleural effusions and is estimated to be at least 3-fold higher. These so-called benign effusions do not follow a “benign course” in many cases, with mortality rates matching and sometimes exceeding those of malignant pleural effusions. In addition to the impact on patients, healthcare systems are also significantly affected, with recent US epidemiological data demonstrating that 75% of resource allocation for pleural effusion management is spent on non-malignant pleural effusions (excluding empyema). Despite this significant burden of disease, and by existing at the junction of multiple medical specialties, reflecting a heterogenous constellation of medical conditions, non-malignant pleural effusions are rarely the focus of research or the subject of management guidelines. With this European Respiratory Society Task Force, we assembled a multispecialty collaborative across 11 countries and three continents to provide a statement based on systematic searches of the medical literature to highlight evidence in the management of the following clinical areas: a diagnostic approach to transudative effusions, heart failure, hepatic hydrothorax, end-stage renal failure, benign asbestos-related pleural effusion, post-surgical effusion and nonspecific pleuritis.

Pleural mesothelioma (PM) is a type of cancer that is highly related to exposure to asbestos fibers. It shows aggressive behavior, and the current therapeutic approaches are usually insufficient to change the poor prognosis. Moreover, apart from staging and histological classification, there are no validated predictors of its response to treatment or its long-term outcomes. Numerous studies have investigated minimally invasive biomarkers in pleural fluid or blood to aid in earlier diagnosis and prognostic assessment of PM. The most studied marker in pleural effusion is mesothelin, which exhibits good specificity but low sensitivity, especially for non-epithelioid PM. Other biomarkers found in pleural fluid include fibulin-3, hyaluronan, microRNAs, and CYFRA-21.1, which have lower diagnostic capabilities but provide prognostic information and have potential roles as therapeutic targets. Serum is the most investigated matrix for biomarkers of PM. Several serum biomarkers in PM have been studied, with mesothelin, osteopontin, and fibulin-3 being the most often tested. A soluble mesothelin-related peptide (SMRP) is the only FDA-approved biomarker in patients with suspected mesothelioma. With different serum and pleural fluid cut-offs, it provides useful information on the diagnosis, prognosis, follow-up, and response to therapy in epithelioid PM. Panels combining different markers and proteomics technologies show promise in terms of improving clinical performance in the diagnosis and monitoring of mesothelioma patients. However, there is still no evidence that early detection can improve the treatment outcomes of PM patients.

Thoracostomy and chest tube placement are key procedures in treating pleural diseases involving the accumulation of fluids (e.g., malignant effusions, serous fluid, pus, or blood) or air (pneumothorax) in the pleural cavity. Initially described by Hippocrates and refined through the centuries, chest drainage achieved a historical milestone in the 19th century with the creation of closed drainage systems to prevent the entry of air into the pleural space and reduce infection risk. The introduction of plastic materials and the Heimlich valve further revolutionized chest tube design and function. Technological advancements led to the availability of various chest tube designs (straight, angled, and pig-tail) and drainage systems, including PVC and silicone tubes with radiopaque stripes for better radiological visualization. Modern chest drainage units can incorporate smart digital systems that monitor and graphically report pleural pressure and evacuated fluid/air, improving patient outcomes. Suction application via wall systems or portable digital devices enhances drainage efficacy, although careful regulation is needed to avoid complications such as re-expansion pulmonary edema or prolonged air leak. To prevent recurrent effusion, particularly due to malignancy, pleurodesis agents can be applied through the chest tube. In cases of non-expandable lung, maintaining a long-term chest drain may be the most appropriate approach and procedures such as the placement of an indwelling pleural catheter can significantly improve quality of life. Continued innovations and rigorous training ensure that chest tube insertion remains a cornerstone of effective pleural disease management. This review provides a comprehensive overview of the historical evolution and modern advancements in pleural drainage. By addressing both current technologies and procedural outcomes, it serves as a valuable resource for healthcare professionals aiming to optimize pleural disease management and patient care.