SESSION TITLE: Pulmonary Manifestations of Systemic Diesase SESSION TYPE: Fellow Case Report Posters PRESENTED ON: 10/09/2018 01:15 PM - 02:15 PM INTRODUCTION: Plasma cell leukemia (PCL) is a rare and aggressive plasma cell malignancy with an increased frequency of extramedullary involvement compared with multiple myeloma. We present a rare case of newly diagnosed PCL with multiple endobronchial lesions. CASE PRESENTATION: The patient is a 62-year-old woman with past medical history of COPD and granular cell tumor of the epiglottis who presented with increasing lethargy and altered mental status over a five-day period. She was cachectic and found to be oriented only to self, with initial lab work showing evidence of acute renal failure and hyperkalemia as well as a leukocytosis of 32,000/μl, hemoglobin level of 5.5 g/dl, and lipase of 7,676. Chest X-ray revealed multifocal opacities and broad-spectrum antibiotics were started for presumed pneumonia. CT of the head revealed a small intraventricular hemorrhage. She required intubation for progressive respiratory failure as well as vasopressors and CVVH. A bronchoscopy was performed, revealing two nodular endobronchial lesions in the right and left main stem bronchi; cryobiopsy of both lesions showed fibrotic tissue with a dense infiltrate of CD138-positive, lambda-restricted atypical cells, consistent with a high-grade plasma cell leukemia. Peripheral flow cytometry also revealed circulating plasma cells. Cultures sent from BAL were unrevealing. Critical illness precluded a more intensive regimen of chemotherapy and a course of intravenous dexamethasone was initiated. DISCUSSION: PCL is a rare and aggressive form of hematologic malignancy with a very poor prognosis, and can be either primary or secondary to end-stage multiple myeloma. It features a higher frequency of extramedullary involvement, anemia, thrombocytopenia, and acute renal failure than multiple myeloma. Extramedullary involvement in PCL is most commonly seen as hepatosplenomegaly and/or lymphadenopathy, with other reported sites of extraosseous involvement including soft tissue adjacent to bone, skin, liver, breast, and kidneys. Endobronchial involvement, particularly in multiple locations, appears to be an exceedingly rare form of extramedullary spread in both MM and PCL. A literature search reveals only two case reports describing the finding of multiple endobronchial plasmacytomas on histology obtained from bronchoscopy, neither in the setting of plasma cell leukemia. Plasma cell infiltration of the lung, termed “myeloma lung,” is a rare cause of acute respiratory failure in multiple myeloma & PCL, and may have explained persistent consolidations on CT scans that did not improve with antibiotics. Due to the severity of her illness, treatment was palliative, and she ultimately passed from complications of respiratory failure. CONCLUSIONS: The presence of multiple endobronchial plasmacytomas is a very rare presentation of extramedullary involvement in multiple myeloma and plasma cell leukemia and likely predicts an very poor prognosis. Reference #1: Niels W. C. J. van de Donk, Henk M. Lokhorst, Kenneth C. Anderson and Paul G. Richardson. “How I treat plasma cell leukemia.” Blood. 2012; 120(12):2376-2389. Reference #2: Joan Blade, Carlos Fernandez de Larrea, Laura Rosinol, Maria Teresa Cibeira, Raquel Jimenez, Ray Powles. “Soft-Tissue Plasmacytomas in Multiple Myeloma: Incidence, Mechanisms of Extramedullary Spread, and Treatment Approach.” Journal of Clinical Oncology. Oct 2011; 29(28):3805-3812. Reference #3: Carmen Montero, Ana Souto, Iria Vidal, Maria del Mar Fernandez, Marina Blanco, Hector Verea. Three Cases of Primary Pulmonary Plasmacytoma. Archivos de Bronconeumologia. 2009; 45(11):564-566. DISCLOSURES: No relevant relationships by Steven Cassady, source=Web Response No relevant relationships by Madhurima Koka, source=Web Response no disclosure on file for Matthew Paparo; No relevant relationships by Edward Pickering, source=Web Response No relevant relationships by Ashutosh Sachdeva, source=Web Response