RESUMEN
OBJECTIVE: Primary pulmonary lymphomas (PPL) are rarely taken into consideration in the differential diagnosis of lung lesions. The aim of this report is to characterize the symptoms, diagnosis and treatment of primary MALT lymphoma of the lung. CASE REPORT: We present the case of a 48-year-old man who was admitted to hospital with a history of coughing, fever, fatigue and non-specific lesions on his chest X-ray. RESULTS: The patient was treated for pneumonia, but showed no improvement. A computer tomography revealed atypical lesions. After an initial examination and tests, no diagnosis could be established. A thoracotomy with an open lung biopsy was performed and MALT lymphoma was finally diagnosed. The patient underwent chemotherapy and showed a significant improvement. CONCLUSIONS: Primary MALT lymphoma is a rare disease and its diagnosis is difficult. There is no non-invasive test that is specific enough, so a proper diagnosis can only be established by a histopathological examination. The disease has a slow and mild course and the response to treatment is satisfactory.