Rapid regression of stage IVb invasive thymoma under palliative corticosteroid administration.

A 53-year-old woman was referred to Matsudo City Hospital for palliative care of stage IVb invasive thymoma with multiple pulmonary metastases and dissemination. Moderate doses of corticosteroid were administered for palliative effects during the preterminal stage of the disease for 2 years. The thymoma progressed slowly but continuously. At age 55, she was admitted to our hospital for a whole-body eruption and high body temperature. We could not identify the pathogen or allergen. Based on the results of a skin biopsy, with the exception of corticosteroid we stopped administering all suspicious medications, including folk medicines. After 1 month of antipyretic therapy, whole-body eruption disappeared and we encountered rapid regression of the thymoma. Unfortunately she died of interstitial pneumonitis only 2 months after the regression.