Clinical identification of malignant pleural effusions

INTRODUCTION

Pleural effusions frequently signal disseminated cancer. Diagnostic markers of pleural malignancy at presentation that would assess cancer risk and would streamline diagnostic decisions remain unidentified.

METHODS

A consecutive cohort of 323 patients with pleural effusion (PE) from different etiologies were recruited between 2013 and 2017 and was retrospectively analyzed. Data included history, chest X-ray, and blood/pleural fluid cell counts and biochemistry. Group comparison, receiver-operator characteristics, unsupervised hierarchical clustering, binary logistic regression, and random forests were used to develop the malignant pleural effusion detection (MAPED) score. MAPED was validated in an independent retrospective UK cohort (n = 238).

RESULTS

Five variables showed significant diagnostic power and were incorporated into the 5-point MAPED score. Age > 55 years, effusion size > 50% of the most affected lung field, pleural neutrophil count 〈 2,500/mm3, effusion protein 〉 3.5 g/dL, and effusion lactate dehydrogenase > 250 U/L, each scoring one point, predicted underlying cancer with the area under curve(AUC) = 0.819 (P < 10-15) in the derivation cohort. The integrated discrimination improvement of MAPED scores showed an increase compared to cytology (p <0.001). Decision curve analysis indicated that the MAPED score generated net clinical benefit. In the validation dataset, the AUC of MAPED scores was 0.723 ( P = 3 × 10-9) for the MAPED score. Interestingly, MAPED correctly identified 33/42(79%) of cytology-negative patients that indeed had cancer.

CONCLUSIONS

The MAPED score identifies malignant pleural effusions with satisfactory accuracy and can be used complementary to cytology to streamline diagnostic procedures.

CONDENSED ABSTRACT

Diagnostic markers for malignant pleural effusions remain uncertain. The MAPED score identifies malignant pleural effusions and complements cytology and confers no additional risk to the patient or cost to the healthcare system.

Medical treatment of pleural infection: antibiotic duration and corticosteroid usefulness

The data about the optimal duration of antibiotics and the usefulness of corticosteroids in the management of parapneumonic effusion and pleural infection are scarce. Two randomised controlled trials evaluating short antibiotic courses (ODAPE and SLIM) and another trial assessing the benefit from corticosteroid use (STOPPE) in this setting were recently published. The aim of this journal club is to present these trials and discuss their significance and limitations. ODAPE compared the efficacy and safety of a short (2 weeks) versus an extended (3 weeks) course of amoxicillin-clavulanate in community-acquired complicated parapneumonic effusions, while SLIM compared the efficacy and safety of short (14-21 days) versus longer (28-42 days) antibiotic courses in patients with community- or hospital-acquired pleural infection. STOPPE assessed the benefit from dexamethasone use in patients with community-acquired pneumonia and concomitant pleural effusion. Both ODAPE and SLIM found that shorter antibiotic courses produce less adverse events while being equally efficacious to the longer courses in a subgroup of patients, such as those with pleural infection that is stabilised with only medical treatment and does not require surgery. In contrast, STOPPE found no benefit from the use of dexamethasone in unselected patients with pneumonia and pleural effusion. Due to the significant limitations of these trials, further studies are required to confirm these findings.

Commentary on

Hassan M, et al. The Short versus Long Antibiotic Course for Pleural Infection Management (SLIM) randomised controlled open-label trial. ERJ Open Res 2023; 9: 00635-2022.Porcel JM, et al. Two vs. three weeks of treatment with amoxicillin-clavulanate for stabilized community-acquired complicated parapneumonic effusions. A preliminary non-inferiority, double-blind, randomized, controlled trial. Pleura Peritoneum 2020; 5: 20190027.Fitzgerald DB, et al. Steroid Therapy and Outcome of Parapneumonic Pleural Effusions (STOPPE): a pilot randomized clinical trial. Am J Respir Crit Care Med 2022; 205: 1093-1101.

KRAS signaling in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) arises from mesothelial cells lining the pleural cavity of asbestos‐exposed individuals and rapidly leads to death. MPM harbors loss‐of‐function mutations in BAP1, NF2, CDKN2A, and TP53, but isolated deletion of these genes alone in mice does not cause MPM and mouse models of the disease are sparse. Here, we show that a proportion of human MPM harbor point mutations, copy number alterations, and overexpression of KRAS with or without TP53 changes. These are likely pathogenic, since ectopic expression of mutant KRAS^G12D in the pleural mesothelium of conditional mice causes epithelioid MPM and cooperates with TP53 deletion to drive a more aggressive disease form with biphasic features and pleural effusions. Murine MPM cell lines derived from these tumors carry the initiating KRAS^G12D lesions, secondary Bap1 alterations, and human MPM‐like gene expression profiles. Moreover, they are transplantable and actionable by KRAS inhibition. Our results indicate that KRAS alterations alone or in accomplice with TP53 alterations likely play an important and underestimated role in a proportion of patients with MPM, which warrants further exploration.

Bacteriology, antibiotic resistance and risk stratification of patients with culture-positive, community-acquired pleural infection

Background

Community-acquired pleural infection (CAPI) is a growing health problem worldwide. Although most CAPI patients recover with antibiotics and pleural drainage, 20% require surgical intervention. The use of inappropriate antibiotics is a common cause of treatment failure. Awareness of the common causative bacteria along with their patterns of antibiotic resistance is critical in the selection of antibiotics in CAPI-patients. This study aimed to define CAPI bacteriology from the positive pleural fluid cultures, determine effective antibiotic regimens and investigate for associations between clinical features and risk for death or antibiotic-resistance, in order to advocate with more invasive techniques in the optimal timing.

Methods

We examined 158 patients with culture positive, CAPI collected both retrospectively (2012-2013) and prospectively (2014-2018). Culture-positive, CAPI patients hospitalized in six tertiary hospitals in Greece were prospectively recruited (N=113). Bacteriological data from retrospectively detected patients were also used (N=45). Logistic regression analysis was performed to identify clinical features related to mortality, presence of certain bacteria and antibiotic resistance.

Results

Streptococci, especially the non-pneumococcal ones, were the most common bacteria among the isolates, which were mostly sensitive to commonly used antibiotic combinations. RAPID score (i.e., clinical score for the stratification of mortality risk in patients with pleural infection; parameters: renal, age, purulence, infection source, and dietary factors), diabetes and CRP were independent predictors of mortality while several patient co-morbidities (e.g., diabetes, malignancy, chronic renal failure, etc.) were related to the presence of certain bacteria or antibiotic resistance.

Conclusions

The dominance of streptococci among pleural fluid isolates from culture-positive, CAPI patients was demonstrated. Common antibiotic regimens were found highly effective in CAPI treatment. The predictive strength of RAPID score for CAPI mortality was confirmed while additional risk factors for mortality and antibiotic resistance were detected.

P238 Chemotherapy venous access port endocarditis in a patient with breast cancer

Funding Acknowledgements

No funding

Background/Introduction

Right sided infective endocarditis (IE) accounts for less than 10% of all IE cases. Predisposing factors include portal of entry, implanted foreign material and unrepaired congenital heart disease with conduit. Fungal endocarditis (FE) constitutes the most severe form of IE and is etiologically connected predominantly to Candida and Aspergillus species. Among these two agents, Candida species is a common nosocomial infection with increasing prevalence and mortality rates up to 40% in cases of systemic candidiasis. Individuals with different forms of solid or hematological malignancies, under chemotherapy regimens or bone marrow transplantation comprise a particularly susceptible patient population.

Case presentation

A 58 year old woman with personal history of triple negative breast adenocarcinoma stage IV under palliative chemotherapy, administered for metastatic mass riknosis in the gastrointestinal tract, was admitted to the Emergency Department of our Hospital due to persistent fever, malaise and dyspnea on effort. Chemotherapy was infused via an implantable venous access port (intraport catheter). Methods/Results: Her heart auscultation revealed a holosystolic ejection type murmur of 3/6 located in the third intercostal space of changing quality. Candida tropicalis was isolated in three separate blood cultures. Transthoracic echocardiography demonstrated a good overall left ventricular systolic function. The right cavities were moderately dilated with moderate tricuspid regurgitation and a pulmonary pressure estimated at 45 mmHg. A large vegetation (approximately 2 cm maximal diameter) at the atrial surface of the posterior and diaphragmatic leaflets of the tricuspid valve with parts of the vegetation periodically apparent in the right ventricle was observed. Transesophageal echocardiography confirmed the findings of the transthoracic study and elucidated in the bicaval view the connection of the vegetation in the tricuspid valve with the edge of the intraport catheter. Moreover computed tomography scan revealed multiple pulmonary emboli in the segmental branches of the bronchial tree and a circumscribed peripheral pulmonary infarct of the left inferior lobe. A multidisciplinary team concluded that the best treatment strategy would require aggressive intravenous combined antifungal therapy until eradication followed by removal of the implantable venous access port, which was uncomplicated.

Conclusions

The majority of fungal endocarditis episodes represented healthcare-associated infections in vulnerable subsets of patients. Treatment of Candida endocarditis can prove challenging because of the formation of biofilms on prosthetic devices often requiring combination therapy. Septic pulmonary embolism with multiple loci is a frequent complication in right sided infective endocarditis. Removal of the prosthetic device if feasible in addition to antifungal treatment is linked to a more favorable prognosis.

Abstract P238 Figure. Chemotherapy intraport endocarditis

Tricuspid Valve Fungal Endocarditis in a Patient with Breast Cancer and an Implantable Chemotherapy Venous Access Port

Fungal endocarditis, a rare and lethal infection, is aetiologically connected with Candida and Aspergillus species. Among these two agents, Candida is a common nosocomial infection with increasing rates over the last years and mortality up to 40% in cases of systemic candidiasis. In the present paper, we describe the case of a 58 year old woman with metastatic breast cancer under palliative chemotherapy who was hospitalized for recurrent episodes of fever due to fungal endocarditis of the implantable venous access port. Such cases may elude the attention of the physician and need to be taken into account especially in oncologic patients with implantable devices under chemotherapy regimens. The treatment of Candida endocarditis can be difficult because of the formation of biofilms on prosthetic devices. The prognosis of these patients may be ameliorated with the combination of fungal and invasive treatment.

Lung nodules: A comprehensive review on current approach and management

In daily clinical practice, radiologists and pulmonologists are faced with incidental radiographic findings of pulmonary nodules. Deciding how to manage these findings is very important as many of them may be benign and require no further action, but others may represent early disease and importantly early-stage lung cancer and require prompt diagnosis and definitive treatment. As the diagnosis of pulmonary nodules includes invasive procedures which can be relatively minimal, such as bronchoscopy or transthoracic aspiration or biopsy, but also more invasive procedures such as thoracic surgical biopsies, and as these procedures are linked to anxiety and to cost, it is important to have clearly defined algorithms for the description, management, and follow-up of these nodules. Clear algorithms for the imaging protocols and the management of positive findings should also exist in lung cancer screening programs, which are already established in the USA and which will hopefully be established worldwide. This article reviews current knowledge on nodule definition, diagnostic evaluation, and management based on literature data and mainly recent guidelines.

Mediastinal staging by videomediastinoscopy in clinical N1 non-small cell lung cancer

Lung cancer is the number one cause of death due to cancer worldwide. According to the World Health Organization, it accounted for 1.69 million new cases in 2015, whereas in Europe, 20.8% of all deaths due to cancer (>266 000 cases) were attributable to lung cancer in 2011 [1, 2].

VAM(LA) has adequate sensitivity to be considered as the approach of choice for preoperative mediastinal staging in the subgroup of early-stage operable NSCLC patientshttp://ow.ly/42Wn30m78Zw

Myeloid-derived interleukin-1β drives oncogenic KRAS-NF-κΒ addiction in malignant pleural effusion

Malignant pleural effusion (MPE) is a frequent metastatic manifestation of human cancers. While we previously identified KRAS mutations as molecular culprits of MPE formation, the underlying mechanism remained unknown. Here, we determine that non-canonical IKKα-RelB pathway activation of KRAS-mutant tumor cells mediates MPE development and this is fueled by host-provided interleukin IL-1β. Indeed, IKKα is required for the MPE-competence of KRAS-mutant tumor cells by activating non-canonical NF-κB signaling. IL-1β fuels addiction of mutant KRAS to IKKα resulting in increased CXCL1 secretion that fosters MPE-associated inflammation. Importantly, IL-1β-mediated NF-κB induction in KRAS-mutant tumor cells, as well as their resulting MPE-competence, can only be blocked by co-inhibition of both KRAS and IKKα, a strategy that overcomes drug resistance to individual treatments. Hence we show that mutant KRAS facilitates IKKα-mediated responsiveness of tumor cells to host IL-1β, thereby establishing a host-to-tumor signaling circuit that culminates in inflammatory MPE development and drug resistance.

Asbestos and the lung: highlights of a detrimental relationship

“Asbestos” is a term used to characterise a number of natural mineral fibres of silica that can be categorised according to their structure in the serpentine-type fibres, mainly represented by chrysotile, and the amphibole-type fibres, which include crocidolite, amosite, anthophyllite, actinolite and tremolite [1]. Due to its remarkable durability and fire resistance, asbestos has been used in pottery and clothing since for at least 4500 years. However, modern commercial production of asbestos began during the second half of the 19th century when industry started to exploit its unique chemical characteristics for manufacturing various products, such as pipe insulation, brake linings, cement pipes, protective clothing, etc. With the increasing use of such materials, individuals working in the construction (e.g. builders, plumbers, etc.) and ship building (e.g. dockyard workers) industries began to be exposed to high concentrations of inhaled asbestos fibres. Approximately 50–70 years after the introduction of asbestos in commercial use, the first reports of asbestos-related diseases emerged [1]. Since then, multiple studies have connected asbestos exposure with a variety of malignant and non-malignant lung disorders.

Novel aspects of the pathogenesis of asbestos-related diseases are still coming to lighthttp://ow.ly/EPDa30e8JqK

Pleural mesothelioma in a young male patient

We present the case of a 33-year-old male patient suffering from lymphocytic pleural effusion, as a result of pleural mesothelioma. Mesothelioma is a malignant tumor of the pleura that is mainly caused by chronic exposure to asbestos fibers and more than 40 years of exposure are needed to develop the disease. Early studies on the relationship of asbestos and mesothelioma were issued in the 1960s. Fibers migrate from the parenchyma of the lung to the visceral pleura. It is widely known that asbestos is an oncogenic factor which can cause damage to DNA. A chest x-ray may reveal pleural effusion with or without pleural thickening, whereas a chest CT may also reveal pleural thickening, uniform and/or lobular. Specific tests, such as immunohistochemical staining, are used in order to help differential diagnosis. Extrapleural pneumonectomy is used as a therapeutic option which involves removal of the lung as well as both the visceral and parietal pleura, the affected part of the pericardium and diaphragm. Surgery should be followed up by radiotherapy and chemotherapy. The surgery may lead to a mean survival rate of approximately 9-21 months. The case presented underlines that in the event of pleural effusion with a lymphocyte type physicians should consider the possibility of a pleural mesothelioma during differential diagnosis, even in relatively young patients.