Thymic hyperplasia following successful chemotherapy. A report of two cases and review of the literature

True thymic hyperplasia is rare in adults. The authors have encountered this entity in two patients who were deemed disease-free following combination chemotherapy for malignant disease. It cannot be assumed that the development of a mediastinal mass or its persistence following chemotherapy is due to recurrent or residual disease. The interrelationship between the immunosuppressive effects of neoplasia and chemotherapy with the resultant thymic overgrowth remains to be clarified.