Lung Adenocarcinoma Required the Differentiation from Wegener Granulomatosis
A 68-year-old man was admitted to our hospital for examination of a nodular shadow newly detected in the right middle lung field, and an inhomogeneous shadow in the left lower lung field detected two years earlier. He had a past history of ulcerative colitis of eight years duration. At first, we suspected Wegener granulomatosis because of elevation of cytoplasmic anti-neutrophil cytoplasmic antibody (C-ANCA) as a laboratory finding on admission. A chest CT scan revealed that the two nodular shadows had cavities, and a bronchoscopic examination was performed. However, because a definite diagnosis could not be made, we carried out video-assisted thoracoscopic surgery (VATS) of the new nodular shadow in the right middle lung field. Subsequently, it was diagnosed as adenocarcinoma. Afterwards, since his C-ANCA level did not decrease even after repeated measurements, we treated the inhomogeneous shadow in the left lower lung field surgically without excluding the possibility of Wegener granulomatosis. Finally, both nodular shadows were diagnosed as adenocarcinoma because there was no leukocytoclastic vasculitis or necrotizing granulomatosis on the histological finding of VATS suspecting of Wegener granulomatosis and we made a diagnosis of primary adenocarcinoma of the left lower lobe of the lung because no malignant lesions were detected in other organs on radiological examinations. We cansidered this case in which C-ANCA was elevated due to ulcerative colitis than to Wegener granulomatosis as noteworthy because the C-ANCA level did not change after surgical resection of the lung cancer.