Nonmesothelial Spindle Cell Tumors of Pleura and Pericardium.

Spindle cell lesions of the pleura and pericardium are rare. Distinction from sarcomatoid mesothelioma, which has a range of morphologic patterns, can be difficult, but accurate diagnosis matters. This article provides practical guidance for the diagnosis of pleural spindle cell neoplasms, focusing on primary lesions.

Performance of CBNAAT on Pleural Biopsies Obtained by Semirigid Thoracoscopy for Diagnosis of Unexplained Pleural Effusion: A Prospective Study from North India.

BACKGROUND: Exudative pleural effusions are commonly encountered in clinical practice, but in about one-fourth of cases, etiology remains elusive after initial evaluation. Medical thoracoscopy with semirigid thoracoscope is a minimally invasive procedure with high diagnostic yield for diagnosing pleural diseases, especially these undiagnosed exudative pleural effusions. In tubercular endemic areas, often, these effusions turn out to be tubercular, but the diagnosis of tubercular pleural effusion is quite challenging due to the paucibacillary nature of the disease. Although culture is the gold standard, it is time-consuming. Cartridge-based nucleic acid amplification test (CBNAAT) is a novel rapid diagnostic test for tuberculosis (TB) and has been recommended as the initial diagnostic test in patients suspected of having extrapulmonary TB (EPTB). MATERIALS AND METHODS: We conducted a prospective observational study of 50 patients with undiagnosed pleural effusion admitted to our tertiary care hospital. The primary aim of the study is to evaluate the diagnostic performance of CBNAAT on thoracoscopic guided pleural biopsy and compare it with conventional diagnostic techniques like histopathology and conventional culture. RESULTS: Of 50 undiagnosed pleural effusions, TB (50%) was the most common etiology. The overall diagnostic yield of semirigid thoracoscopy in this study was 74%. Our study showed that CBNAAT of pleural biopsies had a sensitivity of 36% only but a specificity of 100%. The sensitivity of CBNAAT was not far superior to the conventional culture. CONCLUSION: Tuberculosis (TB) is a common cause of undiagnosed pleural effusion in our set-up. CBNAAT testing of pleural biopsy, though, is a poor rule-out test for pleural TB, but it may aid in the early diagnosis of such patients.

Solitary fibrous tumours of the pleura: do we need a different perspective on malignancy?

OBJECTIVES: Solitary fibrous tumours of the pleura (SFTP) are historically considered to be benign soft tissue neoplasms. However, a clinical relevant number of these neoplasms have malignant histological features. The objective of this study was to evaluate the percentage of SFTP presenting unfavourable clinical behaviour in order to predict negative long-term outcome. METHODS: A retrospective review of 74 patients treated at 4 hospitals between 1990 and 2013 was performed. The median follow-up was 10 years (range: 1-20 years). Risk of tumour recurrence and metastases (unfavourable clinical behaviour) with regard to histology using the Kaplan-Meier and Cox proportional hazards methods. RESULTS: The mean age was 61 years (SD 12.75 years). There were 31 male patients (58%) and 43 female patients (42%). Tumour size ranged from 1 to 30 cm (mean 9.09 cm; SD 6.22 cm). Complete resection (R0) was achieved by minimally invasive thoracoscopic resection in 29% and thoracotomy in 57%; 25% of SFTPs showed histological evidence of malignancy, according to England criteria. Recurrence occurred in 21% and 10% of patients had metastases; 83% of patients with metastases and 39% of patients with recurrence died within 5 years. The median recurrence-free survival for histologically benign SFTP was not reached, compared to 8 years for malignant SFTP. The five-year overall survival rate was 84%. Mitotic rate ≥1/10 HPF, high cellularity, nuclear atypia, Ki-67 level >5% and poorly circumscribed (sessile) growth pattern were associated with poor long-term outcome. CONCLUSIONS: Pathological differentiation of SFTP morphology into pedunculated, well circumscribed and poorly circumscribed (sessile) growth pattern is recommended. Due to the misleading classification into histologically benign and malignant, all unpedunculated SFTP should be classified as potentially aggressive. Lifelong follow-up is mandatory.

The association of visceral pleural invasion with skip N2 metastasis on clinical stage IA NSCLC.

BACKGROUND: Lung lymphatic drainage occurs mainly through a peribronchial path, but it is hypothesized that visceral pleural invasion could alter this path. This study aims to investigate the association between visceral pleural invasion, node upstaging, and N2 skip metastasis and the impact on survival in a population of patients with non-small cell lung cancer of 3 cm or smaller. METHODS: We retrospectively queried our institutional database of lung cancer resection for all patients with clinical stage IA NSCLC between June 2009 and June 2022. We collected baseline characteristics and clinical and pathological staging data. Patients were classified into two groups: The non-VPI group with negative visceral pleural invasion and the VPI group with positive. The primary results analyzed were the occurrence of nodal upstaging, skip N2 metastasis and recurrence. RESULTS: There were 320 patients analyzed. 61.3 % were women; the median age was 65.4 years. The pleural invasion occurred in 44 patients (13.7 %). VPI group had larger nodules (2.3 vs. 1.7 cm; p < 0.0001), higher 18F-FDG uptake (7.4 vs. 3.4; p < 0.0001), and lymph-vascular invasion (35.7 % vs. 13.5 %, p = 0.001). Also, the VPI group had more nodal disease (25.6 % vs. 8.7 %; p = 0.001) and skip N2 metastasis (9.3 % vs. 1.8 %; p = 0.006). VPI was a statistically independent factor for skip N2 metastasis. Recurrence occurred in 17.2 % of the population. 5-year disease-free and overall survival were worse in the VPI group. CONCLUSIONS: The visceral pleural invasion was an independent factor associated with N2 skip metastasis and had worse disease-free and overall survival.

"Diffuse Hot Pleura" in a Case of Recurrent Squamous Cell Carcinoma of the Foot: 18 F-FDG PET/CT Findings.

ABSTRACT: Cutaneous squamous cell carcinoma (cSCC) is the second most common nonmelanoma skin cancer. Unlike basal cell carcinoma, regional lymph nodal metastases and subsequent distant site metastases are more common. Up to approximately 2% to 5% of cSCCs can result in distant metastases. Prognosis is dismal, and median survival is distinctly shortened in case of distant metastatic disease. Diffuse pleural metastases with distinctive overarching unilateral involvement are uncommon. Cutaneous SCC commonly metastasizes to lymph nodes, lungs, liver, bones, and skin. Diffuse unilateral pleural metastasis of cSCC of the foot is extremely rare. We report the case of a 54-year-old man with recurrent cSCC. On follow up restaging, 18 F-FDG PET/CT revealed diffuse nodular bipleural (visceral and parietal) hypermetabolic right pleural thickening, which was later biopsied and turned out to be diffuse pleural metastases from cSCC giving appearance of "hot pleura."

Exploring the molecular and immune-landscape of lung cancer associated with cystic airspaces.

To explore the molecular biological characteristics of lung cancer associated with cystic airspaces (LCCA) and its potential roles on prognosis. A total of 165 LCCAs and 201 non-LCCAs were enrolled in this study. Bulk RNA sequencing was implemented in eight LCCAs and nine non-LCCAs to explore the differentially expressed genes. TCGA data were used to analyze LCCA-specific genes that associated with overall survival (OS). The median age was 60 (IQR 53 to 65) years in LCCA cohort. We found LCCA were predominant in men and had less visceral pleura invasion (VPI) or lympho-vascular invasion (LVI). Moreover, LCCA presented with higher histological heterogeneity. Kaplan-Meier analysis showed that patients of age more than 60 and positive VPI had significantly less PFS in LCCA. Cox regression suggested that LCCA, micropapillary subtype proportion and VPI were the independent risk factors for PFS. LCCA had up-regulated pathways associated with EMT, angiogenesis and cell migration. In addition, LCCA displayed higher levels of immunosuppressor infiltration (M2 macrophages, CAFs and MDSCs) and distinct cell death and metabolic patterns. BCR/TCR repertoire analysis revealed less BCR richness, clonality and high-abundance shared clonotypes in LCCA. Finally, Cox regression analysis identified that four cystic-specific genes, KCNK3, NRN1, PARVB and TRHDE-AS1, were associated with OS of lung adenocarcinoma (LUAD). And cystic-specific risk scores (CSRSs) were calculated to construct a nomogram, which performance well. Our study for the first time indicated significantly distinct molecular biological and immune characteristics between LCCA and non-LCCA, which provide complementary prognostic values in early-stage non-small cell lung cancer (NSCLC).

Pleural epithelioid hemangioendothelioma in a 39-Year-old female: a case report.

BACKGROUND: Epithelioid hemangioendothelioma (EHE) is a rare malignancy of vascular origin which can be primarily be seen in various tissues. EHE originating from the pleura is an even more uncommon subtype which may mimic mesothelioma and pleural carcinomatosis. The prognosis of pleural EHE is poor and there is no consensus on the optimal therapeutic approach. CASE PRESENTATION: A 39-year-old middle-eastern female presented with progressive dyspnea and left shoulder discomfort. Chest computed tomography scan revealed a left side pleural effusion and pleural thickening. Pleuroscopy was done and biopsies were taken which were positive for CD31, CD34, CK, factor 8-R-antigen, and vimentin. Patient was diagnosed with pleural epithelioid hemangioendothelioma (PEHE) and chemotherapy was started and underwent extrapleural pneumonectomy 7 months later. Unfortunately, the patient passed away 10 months after diagnosis due to disease complications. CONCLUSIONS: Once PEHE is suspected in histology it can be confirmed with immunohistochemistry. Chemotherapy, surgery or a combination of both is currently used as the treatment but the standard treatment remains a question.

Single-cell transcriptomic analysis of human pleura reveals stromal heterogeneity and informs in vitro models of mesothelioma.

The pleural lining of the thorax regulates local immunity, inflammation and repair. A variety of conditions, both benign and malignant, including pleural mesothelioma, can affect this tissue. A lack of knowledge concerning the mesothelial and stromal cells comprising the pleura has hampered the development of targeted therapies. Here, we present the first comprehensive single-cell transcriptomic atlas of the human parietal pleura and demonstrate its utility in elucidating pleural biology. We confirm the presence of known universal fibroblasts and describe novel, potentially pleural-specific, fibroblast subtypes. We also present transcriptomic characterisation of multiple in vitro models of benign and malignant mesothelial cells, and characterise these through comparison with in vivo transcriptomic data. While bulk pleural transcriptomes have been reported previously, this is the first study to provide resolution at the single-cell level. We expect our pleural cell atlas will prove invaluable to those studying pleural biology and disease. It has already enabled us to shed light on the transdifferentiation of mesothelial cells, allowing us to develop a simple method for prolonging mesothelial cell differentiation in vitro.

Accidental Detection of Tuberculous Empyema at Health Check-Up.

BACKGROUND: Patients with tuberculous empyema (TE) can have a serious impact on lung function as their disease progresses, and, if left untreated, can cause damage to other parts of the body such as the thorax and spine, causing pain and inconvenience to the patient. Early diagnosis and the search for appropriate treatment are key to improving the survival rate of the disease. METHODS: We report a case of a young patient with an unexpected finding of right pleural effusion on physical examination, who was eventually diagnosed with TE using next-generation sequencing of pleural tissue. We analyzed the literature to improve clinicians' understanding of TE and how to properly diagnose and treat the disease. RESULTS: Laboratory results of the pleural effusion suggested a possible Mycobacterium tuberculosis infection, but pathogen-related tests were negative, and the diagnosis was eventually successfully confirmed by thoracoscopic pleural biopsy. CONCLUSIONS: The diagnosis of TE should be considered in young patients with pleural thickening of the empyema. Adenosine deaminase may provide diagnostic direction in patients with unexplained thorax abscess. Pleural biopsy, although an invasive procedure, is an essential diagnostic tool in some cases.

Defining Optimal Settings for Lung Cryobiopsy in End-Stage Pulmonary Disease. A Human, Ex Vivo, Diseased Lung Clinical Trial.

BACKGROUND: To evaluate optimal settings of probe size, freezing time, and distance to the pleura that influence the size and quality of biopsy specimens during transbronchial lung cryobiopsies in ESPD. METHODS: We prospectively recruited 17 patients undergoing lung transplantation. We created a nonperfused ex vivo bronchoscopy setting to perform multiple cryobiopsies with different probe sizes (1.7, 1.9, and 2.4 mm), freezing times (3, 5, 7, 10, 20, 30 seconds), and probe distance from pleura (5, 10, and 20 mm). Alveolated pulmonary parenchyma area≥50% in histology was considered a good quality biopsy, with a minimum procedural artifact. We used logistic regression to identify independent parameters as risk factors for histologic adequacy. RESULTS: A total of 545 cryobiopsies were obtained from 34 explanted lungs after pneumonectomy for lung transplantation. The mean maximum diameter of the specimen achieved with the 1.7 probe was larger (13.5 mm) than those obtained with 1.9 and 2.4 mm probes (11.3 and 10.7 mm, P= 0.07). More pleural macroscopic damage and pleural tissue in histology occurred with the 2.4 mm probe ( P <0.001). There was no difference in the quality of specimens between the different freezing times and the distance from the pleura. CONCLUSIONS: Freezing time and distance from the pleura did not affect the histologic quality for diagnosing ESPD in severely damaged lungs. Smaller cryoprobe size did not negatively affect sample adequacy.

Diagnostic performance and prognostic value of CT-defined visceral pleural invasion in early-stage lung adenocarcinomas.

OBJECTIVES: To analyze the diagnostic performance and prognostic value of CT-defined visceral pleural invasion (CT-VPI) in early-stage lung adenocarcinomas. METHODS: Among patients with clinical stage I lung adenocarcinomas, half of patients were randomly selected for a diagnostic study, in which five thoracic radiologists determined the presence of CT-VPI. Probabilities for CT-VPI were obtained using deep learning (DL). Areas under the receiver operating characteristic curve (AUCs) and binary diagnostic measures were calculated and compared. Inter-rater agreement was assessed. For all patients, the prognostic value of CT-VPI by two radiologists and DL (using high-sensitivity and high-specificity cutoffs) was investigated using Cox regression. RESULTS: In 681 patients (median age, 65 years [interquartile range, 58-71]; 382 women), pathologic VPI was positive in 130 patients. For the diagnostic study (n = 339), the pooled AUC of five radiologists was similar to that of DL (0.78 vs. 0.79; p = 0.76). The binary diagnostic performance of radiologists was variable (sensitivity, 45.3-71.9%; specificity, 71.6-88.7%). Inter-rater agreement was moderate (weighted Fleiss κ, 0.51; 95%CI: 0.43-0.55). For overall survival (n = 680), CT-VPI by radiologists (adjusted hazard ratio [HR], 1.27 and 0.99; 95%CI: 0.84-1.92 and 0.63-1.56; p = 0.26 and 0.97) or DL (HR, 1.44 and 1.06; 95%CI: 0.86-2.42 and 0.67-1.68; p = 0.17 and 0.80) was not prognostic. CT-VPI by an attending radiologist was prognostic only in radiologically solid tumors (HR, 1.82; 95%CI: 1.07-3.07; p = 0.03). CONCLUSION: The diagnostic performance and prognostic value of CT-VPI are limited in clinical stage I lung adenocarcinomas. This feature may be applied for radiologically solid tumors, but substantial reader variability should be overcome. CLINICAL RELEVANCE STATEMENT: Although the diagnostic performance and prognostic value of CT-VPI are limited in clinical stage I lung adenocarcinomas, this parameter may be applied for radiologically solid tumors with appropriate caution regarding inter-reader variability. KEY POINTS: • Use of CT-defined visceral pleural invasion in clinical staging should be cautious, because prognostic value of CT-defined visceral pleural invasion remains unexplored. • Diagnostic performance and prognostic value of CT-defined visceral pleural invasion varied among radiologists and deep learning. • Role of CT-defined visceral pleural invasion in clinical staging may be limited to radiologically solid tumors.

Mesenchymal tumours of the pleura: review and update.

Primary mesenchymal tumours of the pleura are uncommon and can be diagnostically challenging due to their overlapping histopathologic and immunophenotypic features. Herein we discuss selected mesenchymal tumours of the pleura, including solitary fibrous tumour, calcifying fibrous tumour, desmoid fibromatosis, synovial sarcoma, schwannoma, malignant peripheral nerve sheath tumour, inflammatory myofibroblastic tumour, follicular dendritic cell sarcoma, epithelioid hemangioendothelioma, and desmoplastic small round cell tumour. We review their clinicopathologic characteristics, along with an update on the relevant immunohistochemical and molecular features.

Recognizing the pleura in asbestos-related pleuropulmonary disease: Known and new manifestations of pleural fibrosis.

Pleural thickening (PT) is a major consequence of exposure to all fiber types of asbestos. In recent decades, it is more prevalent than parenchymal asbestosis. Its manifestations occupy a full clinical and radiographic spectrum. Six major manifestations can be identified: (a) acute pleuritis generally with effusion; (b) diffuse PT or fibrous pleuritis; (c) rounded atelectasis; (d) circumscribed PT or plaques; (e) chronic pleuritic pain; and (f) mesothelioma. Review of the experience of workers and community members in Libby, MT to asbestiform fibers in vermiculite has confirmed the appearance of these previously known benign and malignant asbestos-related diseases as well as a unique pleuropulmonary disease characterized as lamellar PT and associated with progressive decline in pulmonary function and pleuritic pain. Despite previous literature asserting that PT represents a marker for asbestos exposure without significant effect on pulmonary function and physiology, the experience of Libby amphibole (LA) disease, along with other studies, indicates that PT plays a role in declining vital capacity in those with prolonged or unusual exposures such as those arising from LA.

[Research progress on immunohistochemical diagnostic markers for malignant pleural mesothelioma].

Malignant pleural mesothelioma (MPM) is a malignant tumor originating from the pleura, characterized by insidious onset, strong local invasiveness, short survival period, and poor prognosis. Clinical diagnosis is of paramount importance for the treatment and prognosis of MPM. Currently, the gold standard for diagnosing MPM is the results of histopathological examinations. Immunohistochemistry (IHC) is an effective auxiliary method in pathological diagnosis. Preliminary examinations can use two positive markers and two negative markers to distinguish pleural metastatic tumors, with additional antibodies selected based on differential diagnosis. The combined use of IHC markers plays a crucial role in the differential diagnosis between MPM and other tumors. This article primarily introduces commonly used IHC markers in MPM and the research progress of novel IHC markers in screening and differential diagnosis, aiming to provide reference for the clinical diagnosis and treatment of MPM.

Staging by Thoracoscopy in potentially radically treatable Lung Cancer associated with Minimal Pleural Effusion (STRATIFY): protocol of a prospective, multicentre, observational study.

INTRODUCTION: Recurrence rate following radical therapy for lung cancer remains high, potentially reflecting occult metastatic disease, and better staging tools are required. Minimal pleural effusion (mini-PE) is associated with particularly high recurrence risk and is defined as an ipsilateral pleural collection (<1/3 hemithorax on chest radiograph), which is either too small to safely aspirate fluid for cytology using a needle, or from which fluid cytology is negative. Thoracoscopy (local anaesthetic thoracoscopy (LAT) or video-assisted thoracoscopic surgery (VATS)) is the gold-standard diagnostic test for pleural malignancy in patients with larger symptomatic effusions. Staging by Thoracoscopy in potentially radically treatable Lung Cancer associated with Minimal Pleural Effusion (STRATIFY) will prospectively evaluate thoracoscopic staging in lung cancer associated-mini-PE for the first time. METHODS AND ANALYSIS: STRATIFY is a prospective multicentre observational study. Recruitment opened in January 2020. The primary objective is to determine the prevalence of detectable occult pleural metastases (OPM). Secondary objectives include assessment of technical feasibility and safety, and the impact of thoracoscopy results on treatment plans, overall survival and recurrence free survival. Inclusion criteria are (1) suspected/confirmed stages I-III lung cancer, (2) mini-PE, (3) Performance Status 0-2 (4), radical treatment feasible if OPM excluded, (5) ≥16 years old and (6) informed consent. Exclusion criteria are any metastatic disease or contraindication to the chosen thoracoscopy method (LAT/VATS). All patients have LAT or VATS within 7 (±5) days of registration, with results returned to lung cancer teams for treatment planning. Following an interim analysis, the sample size was reduced from 96 to 50, based on a lower-than-expected OPM rate. An MRI substudy was removed in November 2022 due to pandemic-related site setup/recruitment delays. These also necessitated a no-cost recruitment extension until October 2023. ETHICS AND DISSEMINATION: Protocol approved by the West of Scotland Research Ethics Committee (Ref: 19/WS/0093). Results will be published in peer-reviewed journals and presented at international meetings. TRIAL REGISTRATION NUMBER: ISRCTN13584097.

Established and new treatment roadmaps for pleural mesothelioma: opinions of the Turkish Collaborative Group.

Pleural mesothelioma (PM) is a cancer of the pleural surface, which is aggressive and may be rapidly fatal. PM is a rare cancer worldwide, but is a relatively common disease in Turkey. Asbestos exposure is the main risk factor and the most common underlying cause of the disease. There have been significant improvements in diagnoses and treatments of many malignancies; however, there are still therapeutic challenges in PM. In this review, we aimed to increase the awareness of health care professionals, oncologists, and pulmonologists by underlining the unmet needs of patients with PM and by emphasizing the need for a multidisciplinary treatment and management of PM. After reviewing the general information about PM, we further discuss the treatment options for patients with PM using immunotherapy and offer evidence for improvements in the clinical outcomes of these patients because of these newer treatment modalities.

Pulmonary manifestations of amyloidosis.

Amyloidosis is caused by abnormal protein deposition in various tissues, including the lungs. Pulmonary manifestations of amyloidosis may be categorized by areas of involvement, such as parenchymal, large airway and pleural involvement. We describe four distinct manifestations of amyloidosis involving the lung and review their clinical, radiological and pathological features and summarize the evidence for treatment in each of these presentations. We describe alveolar-septal amyloidosis, cystic amyloid lung disease, endobronchial amyloidosis and pleural amyloidosis.