HEART FAILURE OR MALIGNANT MESOTHELIOMA? A RARE PRESENTATION OF A RARE DISEASE

Abstract

SESSION TITLE: Medical Student/Resident Disorders of the Pleura Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Malignant pleural mesothelioma is a rare asbestos-related neoplasm that typically presents with nonspecific symptoms such as dyspnea, cough, and chest pain. Imaging usually reveals unilateral pleural disease. Here we present a case of a man who presented with bilateral disease and initial suspicion for cardiogenic etiology. CASE PRESENTATION: A 88-year-old man presented with 2 months of progressive dyspnea on exertion, orthopnea, and unintentional weight loss of 30 pounds. Past medical history included nonobstructive coronary artery disease, chronic diastolic heart failure, diabetes, hypertension, and alcohol abuse. Social history was notable for asbestos exposure through building construction. Physical exam revealed a new oxygen requirement and decreased breath sounds on auscultation bilaterally without other signs of hypervolemia. Troponin-T and NT-proBNP were normal. Chest X-ray showed mild cardiomegaly with bilateral pleural effusions and prominence of the pulmonary vasculature. Cardiac stress test showed a partial inferior reversible perfusion defect, which led to plans for catheterization and echocardiogram. Thoracentesis revealed an exudative effusion (protein 4.3, LDH 271) with negative cytology. Pulmonary function testing showed restrictive lung disease with DLCO 48%. A chest CT scan revealed diffuse interstitial thickening with bilateral bronchial wall and pleural thickening, and a medial right lower lobe mass-like consolidation. PET/CT showed FDG-avid pleural thickening bilaterally with multiple FDG-avid lymph nodes. Ultrasound-guided core biopsy of the right pleura revealed epithelioid malignant mesothelioma. DISCUSSION: Malignant pleural mesothelioma can cause exudative pleural effusions and requires a tissue biopsy for definitive diagnosis. Studies suggest the disease is bilateral in only 10% of cases. As seen in this patient, bilateral pleural effusions in the setting of a recent positive stress test with known CHF history may lead providers to initially attribute the effusions to CHF and possibly defer thoracentesis. Rare presentations of rare diseases are likely low on a provider’s initial differential diagnosis, but thoracentesis should be considered for new effusions especially if there is clinical suspicion for an alternative etiology to CHF. Further diagnostic evaluation may be required if thoracentesis does not yield a definitive diagnosis. Had pulmonary work-up not been pursued for this patient, the diagnosis of malignant mesothelioma may have been delayed. CONCLUSIONS: Malignant pleural mesothelioma should be considered when evaluating new pleural effusions in patients with respiratory symptoms and known asbestos exposure. This case also highlights the importance of maintaining a broad differential diagnosis for a patient with new nonspecific respiratory symptoms. Reference #1: Neumann, V.; Löseke, S.; Nowak, D.; Herth, F.J.; Tannapfel, A. Malignant pleural mesothelioma: Incidence, etiology, diagnosis, treatment, and occupational health. Dtsch. Arztebl. Int. 2013;110:319–326. Reference #2: Gill RR. Imaging of mesothelioma. Recent Results Cancer Res. 2011;189:27-43. Reference #3: Karkhanis VS, and Joshi JM. Pleural effusion: diagnosis, treatment, and management. Open Access Emerg. Med. 2012;4:31–52. DISCLOSURES: No relevant relationships by Sydney Bowmaster, source=Web Response No relevant relationships by Matthew Gosse, source=Web Response No relevant relationships by Jeff Wilson, source=Web Response