A 7 mm lung adenocarcinoma with mediastinal involvement and lymphangiosis carcinomatosa: a case report.

We report a case of a 46-year-old man with a 7 mm lung adenocarcinoma with mediastinal nodal involvement and lymphangiosis carcinomatosa. The resected right middle lobe contained a 7 mm well-differentiated papillary adenocarcinoma and lymphatic vessels towards the hilum were severely involved. The disease was pathologically diagnosed as T1N2M0. Six months after the operation, malignant pleural effusion and multiple bone metastases developed and he died 21 months after the operation. This case indicates that even a very small-sized lung cancer, 1 cm or smaller, could be biologically highly malignant.