EXTENSIVE CYSTIC LUNG DISEASE IN EXTRANODAL MARGINAL ZONE B CELL LYMPHOMA (MALT LYMPHOMA) OF THE LUNG WITH LIGHT CHAIN DEPOSITION DISEASE

TOPIC: Diffuse Lung Disease TYPE: Fellow Case Reports INTRODUCTION: Extranodal marginal zone lymphoma of mucosa associated lymphoid tissue (MALT Lymphoma) is a rare disorder, but the most common cause primary pulmonary involvement. Cystic changes along with nodularity has been previously reported in MALT lymphomas light chain deposition disease (LCDD). CASE PRESENTATION: A 44 y/o smoking female patient presented 3-year history progressive dyspnea setting extensive cystic lung disease. Her cysts had raised concern for lymphangioleiomyomatosis (LAM) and she undergone an open biopsy (OLB) about 2 years prior. She also 10-year Rheumatoid Arthritis (RA) which received methotrexate, adalimumab leflunomide. The OLB was negative LAM, no alternative diagnosis made based on results. Due to dyspnea, our facility where fresh evaluation her case undertaken. repeat CT Chest again confirmed that were not present 12 ago minimally progressed from time two (figure 1). Pulmonary function testing (PFTs) showed severe obstructive pattern positive bronchodilator response. Laboratory results rheumatoid factor, CCP, ANA as well SSA & SSB antibodies. review presence atypical lymphoplasmacytic infiltrate nodular kappa overall consistent extranodal lymphoma). within deposits. PET scan extrathoracic started Rituximab. DISCUSSION: We Lymphoma LCDD presenting airflow obstruction. initially mistaken LAM appropriate therapy delayed years. are causes generally have good prognosis 5-year survival rate exceeding 80% median over 10 Given Sjogren's antibodies cysts; lymphocytic interstitial pneumonia (LIP) considered differential diagnosis. obstruction somewhat this component bronchiolitis obliterans RA could be entirely excluded. CONCLUSIONS: B cell can mimic other such LIP Birt Hogg Dube PLCH. Prognosis Rituximab commonly used initial treatment approach. REFERENCE #1: disease: retrospective cases. Baqir M et al. Respir Med. 2020 Apr; 164:105896. #2: Nodular entity Sjögren syndrome or lymphoma. Arrossi AV J Clin Pathol. 2016 Jun; 69(6): 490-6. #3: mucosa-associated lymphoidtissue revisited. Borie R Eur 2016; 47: 1244-1260. DISCLOSURES: No relevant relationships by Vaibhav Ahluwalia, source=Web Response Hasan Ahmad Albitar, Vivek Iyer,