Ectopic thymoma of the chest wall

A case of ectopic thymoma arising from the chest wall is reported. A chest wall tumour involving the third and fourth ribs and extending extrapleurally and subpectorally was resected following a histopathological diagnosis of hemangioendothelioma obtained at initial incision biopsy. Pathological examination of the excised mass, revealed appearances consistent with a malignant thymoma. No primary thymic tumour was present in the anterior mediastinum so we conclude that the tumour originated in ectopic thymic tissue. To our knowledge a primary thymoma arising within the chest wall has not been reported.