From: A single-center experience: management of patients with thymic epithelial tumors
Stage | Masaoka-Koga staging system |
---|---|
I | Grossly and microscopically completely encapsulated tumor |
II a | Microscopic transcapsular invasion |
II b | Macroscopic invasion into thymic or surrounding fatty tissue, or grossly adherent to but not breaking through mediastinal pleura or pericardium |
III | Macroscopic invasion into a neighboring organ (i.e., pericardium, great vessel, or lung) |
IV a | Pleural or pericardial metastases |
IV b | Lymphogenous or hematogenous metastasis |