Key Points

• International collaborative organizations have dramatically expanded the knowledge base regarding thymic malignancies.
• A reliable clinical diagnosis of thymic malignancy is usually possible for an experienced clinician based on demographic features, radiographic characteristics, and the clinical presentation.
• All thymomas are malignant (but often only slowly progressive).
• Thymomas are frequently associated with a wide variety of autoimmune and neurologic syndromes (most commonly myasthenia gravis).
• Thymic carcinoma and Neuroendocrine tumors of the thymus are more aggressive than thymoma.
• Complete surgical resection is the main treatment intervention.
• Postoperative radiotherapy after R0 resection of stage I thymoma is not beneficial.
• The role of postoperative radiotherapy in thymic carcinoma and stage III thymoma after an R0 resection is unclear.
• Multimodality treatment (e.g., preoperative chemo(radio)therapy, complete resection, adjuvant radiotherapy) for thymic malignancies that are locally advanced or manifest pleural dissemination yields reasonable long-term results.
• Several active chemotherapy regimens have been identified.
• When possible, resection of recurrence (plus chemo- or radiotherapy) results in reasonable long-term outcomes.