Aggressive pulmonary inflammatory pseudotumors

Pulmonary inflammatory pseudotumors are usually unique lesions of unknown e tiology with good prognosis, We report two severe cases with mediastinal in vasion, local recurrence, extrathoracic locations, one of them with a fatal evolution. Certain microscopic features, which were present in our cases ( increased cellularity nuclear pleomorphism, mitotic activity, focal necrosi s, bizarre giant cells, vascular invasion), may have prognostic relevance i n determining an aggressive behavior of these tumors. Surgical resection is the recommended treatment, and incomplete resection, as in our cases, seem s to be a risk factor for developing recurrent inflammatory pseudotumor Imm unosuppressive therapy was ineffective as weld as radiotherapy in one of ou r cases. Only high doses of corticosteroids seemed to slow the evolution of the disease.