P-387: Pulmonary Complications in Plasma Cell Dyscrasia: A Case Series Highlighting Clinical Challenges and Management Strategies

Introduction: Plasma cell dyscrasia (PCD), including multiple myeloma (MM) and AL amyloidosis, significantly impacts pulmonary health. This case-series illustrates the spectrum of pulmonary effects, from plasma cell infiltration to amyloid protein deposition affecting lung function. Despite numerous case reports, systematic reviews and clear epidemiological data on these pulmonary manifestations are limited, highlighting the complexity and variability of respiratory system involvement.

Methods: We present a case-series of five patients treated in our JACIE-accredited Hematology Department. Data were collected retrospectively from systematic chart reviews.

Results: Patient 1: A 75-year-old male presented with a 3-month history of dry cough, dyspnea, and chest pain. 18F-FDG PET/CT revealed a large infiltrating hypermetabolic lung tumor. Biopsy diagnosed solitary primary pulmonary plasmacytoma. The patient achieved complete response with a daratumumab-based regimen.



Patient 2: A 57-year-old with end-stage relapse/refractory MM, presented with shortness of breath. Chest x-rays showed multiple pulmonary nodules. CT-guided lung biopsy confirmed myeloma origin. Pulmonary dissemination of MM is rare, occurring in less than 5% of cases, often misleading clinicians.



Patient 3: A 61-year-old woman with a history of autoimmune disease and light chain MGUS, presented with cardiopulmonary symptoms. Chest x-ray showed lung and pleural calcifications. Pulmonary function testing revealed evidence of impaired CO diffusion. 18F-FDG PET/CT confirmed multiple subpleural and parenchymal hypermetabolic nodules. Biopsy confirmed pulmonary nodular amyloidosis. The patient remains stable without specific treatment. Pulmonary amyloidosis, a rare form of localized amyloidosis, is often asymptomatic and incidentally diagnosed.



Patients 4 and 5, both diagnosed with IgG lambda multiple myeloma: Patient 4, a 66-year-old woman with high-risk cytogenetics at diagnosis, developed cytology-proven myelomatous pleural infiltration and bone progression under second-line daratumumab-based treatment. Switched to teclistamab, she experienced grade III CRS with hypoxemia and acute respiratory distress syndrome, requiring ICU care. Patient 5, a 67-year-old man, developed pleural myeloma invasion during carfilzomib treatment. Despite third-line isatuximab therapy, his disease progressed. He received teclistamab, developing grade II CRS with hypoxemia and CMV disease. Due to active pleural effusion, talc pleurodesis and a thoracic drain were performed. Both of the patients died with uncontrolled pleural effusion. The incidence of myelomatous pleural effusion is estimated to be around 5%. These effusions can lead to a higher risk of severe CRS, and remain difficult to treat.

Conclusions: This case series highlights the pulmonary involvement in PCD. Comparative analysis emphasizes the need for early recognition and tailored interventions to manage pulmonary complications, ultimately improving clinical outcomes.