Thymic tumour

The most common anterior mediastinal tumours in adults.

Thymomas account for the vast majority of thymic neoplasms and are often associated with myasthenia gravis.

About 50% of thymic tumours are diagnosed on incidental finding. A chest CT with intravenous contrast is usually diagnostic.

Small encapsulated tumours are resected for both pathological diagnosis and treatment. Unresectable tumours are usually treated with induction therapy (chemotherapy ± radiotherapy) followed by reassessment for surgery. Patients with myasthenia gravis should have their myasthenia optimised before surgery.

Thymomas are relatively indolent tumours with high cure rates. Prognosis depends on Masaoka's stage, WHO histology, and resection status.

Thymic tumours are rare,[1]Engels EA, Pfeiffer RM. Malignant thymoma in the United States: demographic patterns in incidence and association with subsequent malignancies. Int J Cancer. 2003;105:546-551. http://www.ncbi.nlm.nih.gov/pubmed/12712448?tool=bestpractice.com although they are the most common anterior mediastinal tumours in adults.[2]Girard N, Ruffini E, Marx A, et al. Thymic epithelial tumours: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol. 2015;26(suppl 5):v40-v55. http://annonc.oxfordjournals.org/content/26/suppl_5/v40.long http://www.ncbi.nlm.nih.gov/pubmed/26314779?tool=bestpractice.com Thymomas account for the majority of thymic neoplasms. Common presenting symptoms include chest discomfort, cough, and muscle weakness involving ocular, facial, oropharyngeal and respiratory, and/or limb muscles due to associated myasthenia gravis.[3]Detterbeck FC, Parsons AM. Thymic tumors. Ann Thorac Surg. 2004;77:1860-1869. http://www.ncbi.nlm.nih.gov/pubmed/15111216?tool=bestpractice.com However, about 50% of thymic tumours are diagnosed as an incidental finding.