A previously healthy 19-year-old female of Asian ethnic origin, visited our hospital for an evaluation of abnormal chest CT findings on routine physical examination. On admission the patient was asymptomatic, without fever, cough, lymphadenopathy, night sweats or weight loss. As shown in Table I, the patient had normal complete blood count. Additional tests revealed minimally elevated erythrocyte sedimentation rate. The antinuclear antibody test was negative. The levels of lactate dehydrogenase, beta2 microglobulin and liver function tests were normal. The tests for tuberculosis, human immunodeficiency virus and other viruses, including hepatitis A, B and C, were all negative. The spleen and liver were of normal size and echogenicity. Spiral lung CT revealed bilateral multiple pulmonary consolidations, with the largest lesion sized ~4.5x4.5 cm (Fig. 1). Bone marrow aspiration was negative for lymphoma involvement. The patient underwent CT image-guided biopsy and the diagnosis of pMALToma was confirmed. The microscopic examination revealed lymphoepithelial lesions characterized by diffuse infiltration of the lung parenchyma by small lymphocytes, monocytoid cells and plasma cells (Fig. 2). Immunohistochemical staining demonstrated that the cells were positive for CD20 and B-cell lymphoma 2 protein, with 10% nuclear staining for Ki-67. According to the pathological findings, the patient was treated with 6 courses of chemotherapy with 2 mg vincristine, 4 mg/day chlorambucil plus 30 mg/day prednisolone for 7 days. After 2 cycles of chemotherapy, all the pulmonary lesions were significantly reduced in size (Fig. 3). Complete remission of the lung consolidations was observed following 6 cycles of treatment, as visualized by CT scan (Fig. 4). Fifteen months after the last course of chemotherapy, the patient was in good condition without any evidence of relapse. The patient remains in follow-up.