Treatment of invasive thymoma with single-agent ifosfamide

Purpose: To evaluate single-agent ifosfamide in the treatment of inversive thymoma. Patients and Methods: Fifteen patients (eight merle and seven female) with histologically confirmed invasive thymoma were treated. The median age was 48 years (range, 23 ta 76 years). Four patients had stage III disease, seve n patients had stage IVa disease, and four patients had stage IVb disease. The most common histologic type was lymphoepithelial, Seven patients had re ceived prior treatment, including one patient who received chemotherapy. If osfamide 1.5 g/m(2) was given on days 1 to 5, with mesna as a uroprotector. Results: Thirteen patients were assessable for response. Five complete resp onses (38.5%; 95% confidence interval [CI], 17.7% to 64.5%) and one partial response (7.7%; 95% CI, 1.4% to 33.3%) were seen. The median duration of c omplete response was 66 + months (range, 25 to 87 months), and the estimate d survival rate 5 years after ifosfamide treatment was 57% (SE, 32% to 79%) . The most frequent toxicities were nausea, vomiting, and leucopenia, but t hese were well tolerated. Conclusion: Single-agent ifosfamide possesses significant activity against invasive thymoma and is comparable to currently used combination regimens. The inclusion of ifosfamide in combination therapy, particularly in place o f cyclophosphamide in regimens such as cisplatin, doxorubicin, and cyclopho sphamide, needs to be evaluated. (C) 1999 by American Society of Clinical O ncology.