Pulmonary Marginal Zone B-Cell Lymphoma of Mucosa-Associated Lymphoid Tissue (PMZL-MALT) Diagnosed by Radial Probe Endobronchial Ultrasound-Guided Biopsy: A Case Report.

This case report presents a rare case of primary pulmonary marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (PMZL-MALT). Follow-up lung imaging performed 17 months after the initial presentation showed persistent pulmonary consolidation. After a radial probe endobronchial ultrasound (RP-EBUS)-guided transbronchial lung biopsy, histopathological analysis confirmed the diagnosis of primary PMZL-MALT. Notably, while RP-EBUS is commonly used for solitary peripheral pulmonary lesions, its value in asymptomatic, bilateral, nonspecific consolidations-an easily misdiagnosed scenario often leading to unnecessary invasive procedures-remains underrecognized, which this case is aimed at highlighting. Our report is aimed at raising clinical awareness of this disease and promoting early diagnosis and treatment.