Decoding Pulmonary Mucosa-Associated Lymphoid Tissue Lymphoma: A Journey Through Unilateral Cystic Pulmonary Manifestations—A Rare Case and Literature Review

Abstract We presented an atypical case of a 62-year-old female diagnosed with pulmonary Mucosa-Associated Lymphoid Tissue (p-MALT) lymphoma, uniquely manifesting as a singular cystic lesion in the lung. Diagnostic evaluations, including comprehensive imaging, bronchoscopy, and CT-guided lung biopsy, revealed this uncommon radiological presentation. Detailed histopathological and immunohistochemical assessments further cemented the diagnosis. To determine the disease's extent, systemic evaluations such as whole-body PET-CT, gastroscopy, colonoscopy, and bone marrow biopsy were conducted, confirming its localized nature. Following the definitive diagnosis, the patient underwent a Rituximab-centric therapeutic regimen, yielding significant clinical improvement. This case accentuates the importance of recognizing distinctive cystic lung features in p-MALT lymphoma and the indispensable role of holistic diagnostic approaches in guiding precise therapeutic and prognostic decisions.