[A case of pulmonary low-grade B cell lymphoma (MALT type) presenting seven years after gastric lymphoma resection].

A 71-year-old man was admitted to our hospital because of systemic edema and exertional dyspnea. Chest radiographs revealed infiltrative shadows in both lung fields, pleural effusion, and pericardial effusion. Seven years before, he had undergone gastric surgery for a gastric ulcer with lymphoid hyperplasia. In the pathologic diagnosis based on the percutaneous lung biopsy, hyalinizing granuloma was suspected. For a more thorough diagnosis, the patient was subjected to an open lung biopsy, and the final diagnosis was low-grade B-cell lymphoma of the MALT (mucosa-associated lymphoid tissue) type. Gallium scintigraphy showed accentuated accumulation in the left neck and hypothyroidism was present. Histologic re-examination of the resected stomach revealed infiltration of centrocyte-like cells and lymphoepithelial lesions, compatible with the pathologic features of MALT lymphoma. We considered that the gastric neoplasm and the pulmonary, pleural, and thyroid tumors of MALT lymphoma had occurred seven years apart in this case. Thyroid hormone replacement and CHOP therapy improved the symptoms and decreased the lung tumor size by 73%. MALT lymphomas tend to remain localized for a long period. The multiorgan involvement seen in this case is rather rare.