A progressive ground-glass opacity occupied the lower left lung in a postoperative colon cancer patient, what it will be?—a case report

Primary pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma is a type of non-Hodgkin lymphoma, and it occurs frequently in the stomach and rarely in the lungs. They are rarely taken into consideration in the differential diagnosis of lung lesions. MALT lymphomas affecting the lung show various styles on chest CT, which range from typical nodules or areas of consolidation to findings that are extremely rare, such as a progressive ground glass opacity (GGO) that never been reported before especially in a postoperative colon cancer patient. The postoperative pathologic diagnosis of the progressive GGO was extranodal marginal zone B-cell lymphoma of MALT. And during 2-year follow-up, the patient was in good condition and there was no sign of recurrence. This case would enrich the manifestations and increase the understanding in MALT, and inappropriate treatment would be avoided.