[Case of pulmonary inflammatory pseudotumor with cysts].

We herein report a case involving a 58-year-old female patient with multiple cystic lesions in the right lobe of the lung. The lesions were revealed on chest computed tomography in 2002 and followed up. Transbronchial lung biopsy showed no malignancy in June 2013. The lesions gradually increased in size and thickness and were associated with fluid-filled cysts. We performed a right lower lobectomy in November 2013. Pathological examination revealed inflammatory pseudotumor. Such a case of inflammatory pseudotumor presenting as a pulmonary cyst has not been previously described. Intractable infection and inflammation are regarded as common causes of inflammatory pseudotumor. This condition should be considered in patients with a medical history consistent with infectious disease and a pulmonary cyst found on chest computed tomography.