Pulmonary mucosa-associated lymphoid tissue lymphoma masquerading as pneumonia in a 63-year-old female

SESSION TITLE: Lung Cancer Case Report Posters 12 SESSION TYPE: Case Report Posters PRESENTED ON: 10/09/2023 02:10 pm - 02:55 pm INTRODUCTION: Mucosa-associated lymphoid tissue (MALT) lymphomas are a subset of non-Hodgkin lymphomas, predominantly arising in the gastrointestinal tract. They can occasionally manifest in other extranodal sites, including the lungs. (1) We present a case of pulmonary MALT lymphoma in a 63-year-old female with symptoms mimicking pneumonia, emphasizing the necessity of comprehensive diagnostic workup and consideration of rare etiologies in patients presenting with progressive respiratory symptoms. CASE PRESENTATION: A 63-year-old female with a medical history significant for hyperparathyroidism, herpes simplex 1 infection, and asthma was admitted to the hospital with a three-month history of worsening cough and shortness of breath. Contrast CT chest revealed near-complete consolidation of the left upper lobe, multifocal airspace densities bilaterally, small left pleural effusion, lymphadenopathy involving paratracheal, prevascular, aorticopulmonary window, and subcarinal. The patient was initially started on broad-spectrum antibiotics, which were subsequently narrowed down to Unasyn. However, her symptoms worsened, with an increase in cough and hypoxia. The patient underwent bronchoalveolar lavage (BAL) and transbronchial biopsies from the left upper lobe, along with endobronchial ultrasound (EBUS) sampling of the lymph nodes. Flow cytometry demonstrated a monoclonal B-cell population. Pathology results from the biopsy sample confirmed the presence of MALT lymphoma. The patient was subsequently started on Cytoxan and Rituxan. DISCUSSION: Pulmonary MALT lymphoma can present with non-specific symptoms, such as cough and shortness of breath, often leading to an initial diagnosis of pneumonia. (2-3) However, the lack of clinical improvement following appropriate antibiotic treatment should prompt clinicians to consider alternative diagnoses. The comprehensive diagnostic workup, including imaging, BAL, transbronchial biopsies, and EBUS sampling, was crucial in identifying the underlying MALT lymphoma in this case. Early recognition and appropriate management of such rare etiologies can significantly impact patient outcomes. CONCLUSIONS: Clinicians should be aware of the potential for MALT lymphoma to masquerade as pneumonia, particularly in cases where patients do not respond to conventional therapies as expected. Thorough diagnostic workup and timely intervention are essential to ensure optimal patient outcomes. REFERENCE #1: 1. Nahorecki A, Chabowski M, Straszak E, Teplicki A, Szuba A, Langfort R, Janczak D. Primary pulmonary MALT lymphoma-case report and literature overview. Eur Rev Med Pharmacol Sci. 2016 May 1;20(10):2065-9. REFERENCE #2: 2. Graham BB, Mathisen DJ, Mark EJ, Takvorian RW. Primary pulmonary lymphoma. The Annals of thoracic surgery. 2005 Oct 1;80(4):1248-53. REFERENCE #3: 3. Borie R, Wislez M, Thabut G, Antoine M, Rabbat A, Couderc LJ, Monnet I, Nunes H, Blanc FX, Mal H, Bergeron A. Clinical characteristics and prognostic factors of pulmonary MALT lymphoma. European Respiratory Journal. 2009 Dec 1;34(6):1408-16. DISCLOSURES: No relevant relationships by Hemanth Krishna Boppana No relevant relationships by Ming-Yan Chow No relevant relationships by Ahmed Elkhapery No relevant relationships by Unaiza Faizan No relevant relationships by Chengu Niu No relevant relationships by Hina Ukrani No relevant relationships by Qian Zhang No relevant relationships by Jing Zhang