Thymic atrophy and rebound enlargement following chemotherapy for testicular cancer.

Serial thoracic CT scans of 50 consecutive patients with testicular cancer were reviewed. In 30 of them with metastatic disease treated according to the Einhorn Scheme changes in thymic size caused by cytostatic agents were studied. During chemotherapy 78.6 per cent of all patients examined developed thymic atrophy, followed by rebound enlargement that reached its culminating point 13 months after initiation of treatment. After that a slow (approximately 2 years) involution process began, until the initial size or somewhat smaller size was re-achieved. The other 20 patients with no evidence of metastases, and therefore not treated with chemotherapy, showed no changes in thymic size. Rebound thymic enlargement following cytostatic therapy for metastatic testicular cancer should not be mistaken for lymphadenopathy.