A Rare Case of Inflammatory Myofibroblastic Tumor Causing Left Pulmonary Artery Stenosis and Successfully Treated with Localized Radiotherapy in a Patient with Perinuclear Antineutrophil Cytoplasmic Antibody Vasculitis

Inflammatory myofibroblastic tumor (IMT) of the lung is a rare neoplasm that commonly behaves in an indolent fashion and is generally treated with complete surgical excision. The management of unresectable IMT presents a significant challenge, especially in cases with multiple comorbidities, and a consensus has yet to be reached on the most appropriate first-line modality. We present a case of unresectable IMT causing severe stenosis of the left pulmonary artery in a patient on immunosuppressive therapy for perinuclear antineutrophil cytoplasmic antibody vasculitis. The patient was successfully treated with localized radiotherapy to a total dose of 45 Gy in five weeks, and has been followed for more than seven years since treatment. In this case report, we review the pertinent literature and illustrate the difficulties in diagnosing and treating rare neoplasms in a patient with significant medical comorbidities.