[A case of inflammatory pseudotumor of the lung: relation to metastasizing leiomyoma]

A 61-year-old woman was referred to our clinic because of an abnormal shadow in the left lower lung field on an X-ray taken at a regular checkup. She had no subjective symptoms. Past history included myoma uteri at 47 yr and iatrogenic left pneumothorax subsequent to acupuncture for muscle pain in the shoulder. On CT, a solitary round lesion 2.5 cm in diameter and smooth margin was located at S5 just below the visceral pleura. Since we were unable to obtain a histological diagnosis by bronchofiberscopy, thoracotomy was carried out and the lesion was resected. The intraoperative pathological diagnosis was a benign lesion resembling leiomyoma. After surgery, re-evaluation of the myoma uteri specimen resected 14 years previously was done, as well as desmin immunohistochemical staining of the lung lesion, which demonstrated no evidence of a smooth muscle component in the latter. The final diagnosis was inflammatory pseudotumor.