Multiple inflammatory myofibroblastic tumors involving lung and mediastinum: a rare clinical entity

Inflammatory myofibroblastic tumors (IMT) are a rare clinical entity. We retrospectively reviewed the clinicopathological characteristics and prognosis for all patients with surgically resected IMTs of the lung at our institution.

From January 1995 through February 2007, 16 patients, 9 men and 7 women ranging in age from 18 to 64 years with a median age of 46 years, were admitted to our hospital for IMT of the lung, mediastinum and thoracic outlet. Nine of them (56.3 %) had a history of pneumonia, while in the rest it was documented as an incidental finding on chest X-ray. Five of our patients (31.3 %) were under immunosuppressive therapy. CT scan was the diagnostic tool routinely used and PET performed turned out to be positive in 5 cases. Wedge resection was performed in the majority of cases along with 2 lobectomies and 2 segmentectomies. The resected lesions were studied histologically and immunohistochemically. There were no operative deaths. Follow-up was complete in all patients and ranged from 9 months to 135 months. No recurrence was observed.

Overall 5-year survival was 93.8 %. Fifteen patients are still alive and the cause of death in one case was not related to the pseudotumor. Cox regression analysis was performed for different factors such as age, sex, previous pneumonia and immunosuppression. None of them was found to play a role in the development of an IMT. The type of intervention also did not seem to affect the prognosis in our series.

IMTs are a rare clinical entity. An accurate preoperative diagnosis is difficult and complete resection remains the treatment of choice and leads to an excellent survival.