Aggressive angiomyxoma of the lung.

Aggressive angiomyxoma (AAM) is a rare mesenchymal neoplasm that usually occurs in the pelvic-perineal region. Only two cases of AAM occurring outside this region have been reported. The case of AAM reported here originated from lung. A 70-year-old woman was admitted for evaluation of an incidentally detected pulmonary mass on chest radiography. Tumour resection under the thoracoscopy was performed. Pathological examination revealed microscopical features that were characteristic of AAM. The features were oval- to spindle-shaped tumour cells in a myxoid stroma, hyalinised thick vessels, and characteristic immunophenotype. The differential diagnosis of AAM and other mesenchymal neoplasms of lung is also discussed.