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 , 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, β2 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 ~4.5×4.5 cm (). 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 (). 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 (). Complete remission of the lung consolidations was observed following 6 cycles of treatment, as visualized by CT scan (). 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.
An 83-year-old male with past medical history of mild Alzheimer's dementia, nonischemic cardiomyopathy, aortic regurgitation, and an ascending aortic aneurysm measured at 4.1 cm presented to the pulmonology clinic with an abnormal CT of the chest. He was seen by his PCP recently for follow-up of ascending aortic aneurysm and had a CT chest without contrast performed which showed 14.8 mm pleural-based nodular density in the posterior medial right upper lobe, irregular 20.5 mm right lower lobe nodule, and a 2 mm left upper lobe partially calcified nodule []. He had no respiratory or constitutional symptoms. He was a lifelong nonsmoker without any significant occupational exposures. [18F]Fluorodeoxyglucose-positron emission tomography with CT (18F –FDG PET/CT) was performed showing multiple 18F –FDG avid nodules in the right upper lobe, right lower lobe, and left upper lobe []. Initially thought to be inflammatory in nature, a 3-month follow-up CT chest was recommended; however, the patient opted for CT-guided transthoracic biopsy. Because the tissue sample was a core needle biopsy of a pleural-based nodule, it did not include any bronchial epithelium; therefore, the presence of lymphoepithelial lesions could not be evaluated. Immunohistochemical staining showed CD20 positive neoplastic B cells with CD3 positive small benign T cells. CD21 stain was also positive within the residual dendritic cell network, such that the marginal zones appeared to be expanded. These findings support a histopathologic diagnosis of low-grade B-cell NHL most consistent with marginal zone lymphoma []. The patient was referred to oncology for further management.