A Rare Case of Pulmonary Plasmacytoma with Multiple Myeloma Presenting with Bilateral Consolidative Cavitary Lung Lesions

Abstract

Primary pulmonary plasmacytoma is a rare plasma cell neoplasm. Most reported cases involve the upper aerodigestive tract. Here, we report a 58‐year‐old male presenting with bilateral consolidative cavitary lung lesions. After an extensive investigation, the diagnosis of pulmonary plasmacytoma was suggested and then confirmed with histological and immunohistochemical examinations in addition to kappa light chain paraproteinemia that progressed to multiple myeloma. An autoimmune work-up showed that cytoplasmic and perinuclear antineutrophil cytoplasmic antibodies (C-ANCA and P-ANCA) and other various antibodies being positive but without evidence of vasculitis or autoimmune disease. The patient was started on bortezomib, cyclophosphamide, and dexamethasone chemotherapy for three cycles but subsequently developed a respiratory infection that required intensive care management; he died after few months.