A Case of Inflammatory Pseudotumor of the Lung Infiltrating the Chest Wall

Abstract

Differential diagnosis between an inflammatory pseudotumor infiltrating the chest wall and neoplasm was difficult. A 67-year-old man was admitted due to a mass with cavitation in the right upper lung field in the chest roentogenogram. The lesion gradually increased in size. Right upper lobectomy with chest wall resection was performed. The 48-54mm tumor was fixed to the chest wall suggesting invasion by malignant tumor. Histologically, the tumor was formed by spindle cells. Lymphocytes, histiocytes, plasma cells infiltrated bundles of spindle cells.
Immunohistochemical staining of the tumor cells revealed strongly positive findings for PCNA in both tumor and site of infiltration. However, the tumor cells had no immunoactivity for P53. Flow cytometric determination of the tumor cell DNA content conducted on paraffin-embedded tissues revealed a diploid pattern. The patients have remained well for three years without recurrence.