SOLITARY EXTRAMEDULLARY PLASMACYTOMA CAUSING PROXIMAL ENDOBRONCHIAL OBSTRUCTION

TOPIC: Lung Cancer TYPE: Medical Student/Resident Case Reports INTRODUCTION: Extramedullary plasmacytomas can arise in patients with systemic multiple myeloma and should not be confused solitary extramedullary plasmacytoma (SEP). SEP refers to a non-osseous plasma cell neoplasm without evidence of myeloma. SEP, observed 3% all neoplasms, is usually located the upper aerodigestive tract.1 Endobronchial obstruction due very rare. CASE PRESENTATION: We report case 50 year old non-smoking male history asthma left sided pneumonia who presented three nonproductive cough dyspnea. Computerized tomography chest showed 4 cm mass extending into mainstem bronchus (LMB), post-obstructive atelectasis, mediastinal adenopathy pleural thickening (figure 1). His labs did demonstrate anemia, hypercalcemia, or renal insufficiency. Bronchoscopy demonstrated 99% occlusion proximal LMB by an exophytic tumor 2). He underwent extensive endobronchial debulking. biopsy 3) confirmed monoclonal neoplasm. Mass spectrometry kappa immunoglobulin light chains no amyloid-associated proteins. Bone marrow normocellular mildly increased cells. Serum protein electrophoresis show spike. Beta-2-microglobulin was normal. Positron emission scan FDG uptake mild uptake. The patient diagnosed received targeted external beam radiotherapy (4500 cGy 25 fractions) favorable response. DISCUSSION: lungs, while rare, most frequently presents as lung nodules. involvement uncommon occur proximally trachea bronchi distally. Only two other have shown chain extracellular deposits.2 Most pulmonary are treated surgical resection, radiation therapy, palliative bronchoscopic interventions.3 Initial reports suggested that therapy may superior however, assertion has been challenged. Nevertheless, these tumors do appear highly radiosensitive. CONCLUSIONS: rare cause obstruction. Proper immunohistopathology confirms SEP. While options used some instances, intent cure considered for disease. REFERENCE #1: Dores GM, Landgren O, McGlynn KA, Curtis RE, Linet MS, Devesa SS. Plasmacytoma bone, plasmacytoma, myeloma: incidence survival United States, 1992-2004. Br J Haematol. 2009 Jan;144(1):86-94. doi: 10.1111/j.1365-2141.2008.07421.x. Epub 2008 Nov 11. PMID: 19016727; PMCID: PMC2610331. #2: Liu HY, Luo XM, Zhou SH, Zheng ZJ. Prognosis expression lambda head neck: literature review. Int Med Res. 2010 Jan-Feb;38(1):282-8. 10.1177/147323001003800133. 20233540. #3: Park JI, Lee YY, SS, Ahn JH. A primary plasmacytoma. Thoracic Cancer. 2021;12:958–961. https://doi.org/10.1111/1759-771 4.1385 DISCLOSURES: No relevant relationships Urbee Haque, source=Web Response Randall Harris, Sonya Joshi, Jason Lane, Sujith Modugula, Sanjiv Tewari,