A 69-YEAR-OLD MAN WITH HEAVY ASBESTOS EXPOSURE, DYSPNEA, AND PLEURAL SOFT-TISSUE THICKENING

Abstract

SESSION TITLE: Invasion of the PleuraSESSION TYPE: Case ReportsPRESENTED ON: 10/18/2022 11:15 am - 12:15 pmINTRODUCTION: Amyloidosis is a disease caused by autologous protein deposition in tissues in the form of fibrils. It can affect any organ and can be fatal if left untreated. Most common pulmonary involvement with amyloid is nodular amyloidosis. Pleural disease is very rare and presents most commonly as recurrent pleural effusion (1). It can mimic multiple diseases including malignant mesothelioma.CASE PRESENTATION: A 69-year-old male patient with a history of asbestos exposure presented for worsening dyspnea on exertion over 3 months accompanied with a dry cough. He worked installing asbestos from age 18-23. Physical exam was pertinent for decreased bibasilar breath sounds. Laboratory studies were unremarkable. PFTs showed severe restriction with severely reduced DLCO. CT chest showed bilateral pleural effusions and worsening multifocal pleural plaques compared to a prior CT chest. It was associated with pleural and soft tissue thickening invading the left upper mediastinum. PET CT showed low FDG uptake (Fig1A&B). Pleural fluid was exudative per Light's criteria. Microscopic evaluation of two pleural nodules showed extensive amyloid infiltration with a positive Congo red stain. Immunohistochemical stains were positive for CD20 and CD138 specific for small B-cells and plasma cells respectively (Fig1C&D). He was diagnosed with systemic amyloidosis and started on chemotherapyDISCUSSION: Our case represents a very rare presentation of pleural amyloidosis with disseminated amyloid lesions on the parietal, visceral and diaphragmatic pleura. Similar cases were only rarely reported in the literature. Whether extensive asbestos exposure can lead to pleural amyloidosis is unclear. Hiroshima et al described a case of nodular pulmonary amyloidosis in a patient with a history of asbestos exposure and suggested asbestos fibers as an etiology (2). The differential diagnosis of amyloidosis is broad including interstitial lung disease, malignant mesothelioma, pleural infection and malignancy. It has been thought to be strongly associated with lymphoproliferative disorders including plasma cell dyscrasias. A pathological diagnosis is crucial and evaluation for second organ involvement is vital for prognostication and gauging therapy. Furthermore, the finding of significantly reduced DACO suggests a process in addition to restriction affecting diffusion such as parenchymal involvement with amyloidosis or asbestosisCONCLUSIONS: In brief, the diagnosis of amyloidosis can be challenging as it can mimic other diseases including malignant mesothelioma. Our patient had a history of asbestos exposure and malignant mesothelioma was highly suspected. It is essential to keep a broad differential when approaching pleural diseases and recommend a thorough workup. First line therapy is stem cell transplant, Berk et al shows a significant survival rate in patients treated with SCT or chemotherapy compared to untreated patients (3).Reference #1: Dacic S, Colby TV, Yousem SA. Nodular Amyloidoma and Primary Pulmonary Lymphoma with Amyloid Production: A Differential Diagnostic Problem. Mod Pathol. 2000 Sep;13(9):934–40.Reference #2: Hiroshima K, Ohwada H, Ishibashi M, Yamamoto N, Tamiya N, Yamaguchi Y. Nodular pulmonary amyloidosis associated with asbestos exposure. Pathol Int. 1996 Jan;46(1):66–70.Reference #3: Berk JL, Keane J, Seldin DC, Sanchorawala V, Koyama J, Dember LM, et al. Persistent Pleural Effusions in Primary Systemic Amyloidosis. Chest. 2003 Sep;124(3):969–77.DISCLOSURES: No relevant relationships by Ahmed AlhusseinyNo relevant relationships by Jean-Pierre AssakerNo relevant relationships by Douglas Johnson SESSION TITLE: Invasion of the Pleura SESSION TYPE: Case Reports PRESENTED ON: 10/18/2022 11:15 am - 12:15 pm INTRODUCTION: Amyloidosis is a disease caused by autologous protein deposition in tissues in the form of fibrils. It can affect any organ and can be fatal if left untreated. Most common pulmonary involvement with amyloid is nodular amyloidosis. Pleural disease is very rare and presents most commonly as recurrent pleural effusion (1). It can mimic multiple diseases including malignant mesothelioma. CASE PRESENTATION: A 69-year-old male patient with a history of asbestos exposure presented for worsening dyspnea on exertion over 3 months accompanied with a dry cough. He worked installing asbestos from age 18-23. Physical exam was pertinent for decreased bibasilar breath sounds. Laboratory studies were unremarkable. PFTs showed severe restriction with severely reduced DLCO. CT chest showed bilateral pleural effusions and worsening multifocal pleural plaques compared to a prior CT chest. It was associated with pleural and soft tissue thickening invading the left upper mediastinum. PET CT showed low FDG uptake (Fig1A&B). Pleural fluid was exudative per Light's criteria. Microscopic evaluation of two pleural nodules showed extensive amyloid infiltration with a positive Congo red stain. Immunohistochemical stains were positive for CD20 and CD138 specific for small B-cells and plasma cells respectively (Fig1C&D). He was diagnosed with systemic amyloidosis and started on chemotherapy DISCUSSION: Our case represents a very rare presentation of pleural amyloidosis with disseminated amyloid lesions on the parietal, visceral and diaphragmatic pleura. Similar cases were only rarely reported in the literature. Whether extensive asbestos exposure can lead to pleural amyloidosis is unclear. Hiroshima et al described a case of nodular pulmonary amyloidosis in a patient with a history of asbestos exposure and suggested asbestos fibers as an etiology (2). The differential diagnosis of amyloidosis is broad including interstitial lung disease, malignant mesothelioma, pleural infection and malignancy. It has been thought to be strongly associated with lymphoproliferative disorders including plasma cell dyscrasias. A pathological diagnosis is crucial and evaluation for second organ involvement is vital for prognostication and gauging therapy. Furthermore, the finding of significantly reduced DACO suggests a process in addition to restriction affecting diffusion such as parenchymal involvement with amyloidosis or asbestosis CONCLUSIONS: In brief, the diagnosis of amyloidosis can be challenging as it can mimic other diseases including malignant mesothelioma. Our patient had a history of asbestos exposure and malignant mesothelioma was highly suspected. It is essential to keep a broad differential when approaching pleural diseases and recommend a thorough workup. First line therapy is stem cell transplant, Berk et al shows a significant survival rate in patients treated with SCT or chemotherapy compared to untreated patients (3). Reference #1: Dacic S, Colby TV, Yousem SA. Nodular Amyloidoma and Primary Pulmonary Lymphoma with Amyloid Production: A Differential Diagnostic Problem. Mod Pathol. 2000 Sep;13(9):934–40. Reference #2: Hiroshima K, Ohwada H, Ishibashi M, Yamamoto N, Tamiya N, Yamaguchi Y. Nodular pulmonary amyloidosis associated with asbestos exposure. Pathol Int. 1996 Jan;46(1):66–70. Reference #3: Berk JL, Keane J, Seldin DC, Sanchorawala V, Koyama J, Dember LM, et al. Persistent Pleural Effusions in Primary Systemic Amyloidosis. Chest. 2003 Sep;124(3):969–77. DISCLOSURES: No relevant relationships by Ahmed Alhusseiny No relevant relationships by Jean-Pierre Assaker No relevant relationships by Douglas Johnson