Differential diagnosis of proptosis: report of 2 cases.

We rarely encounter patients with proptosis, however, it is known that inflammation and extension of paranasal sinus tumors may cause this condition. We should consider the diseases that may cause proptosis to facilitate the diagnosis. Recently, we treated proptosis in 2 cases, one with inflammatory myofibroblastic tumor (IMT) and the other with malignant lymphoma. As these 2 diseases show various clinical features and these features frequently overlap, it is difficult to differentiate between IMT and malignant lymphoma without pathological examinations. In this study, we review the relevant literature reports and discuss the difficulties in establishing a clinicopathological diagnosis and present a slight distinction in magnetic resonance imaging.