High-dose carboplatin with etoposide in patients with recurrent thymoma: the Indiana University experience

Thymoma is a chemotherapy-sensitive tumor with a 30-50% 5-year survival in previously untreated patients. Unfortunately, durable CRs with salvage chemotherapy are rarely observed. We initiated a phase II trial of high-dose carboplatin and etoposide in patients with relapsed thymoma or thymic carcinoma. All patients had progressive disease (PD) after initial or salvage chemotherapy, but were not cisplatin-refractory. PBSCs were mobilized using 10 mug/kg/day G-CSF. Patients received carboplatin 700 mg/m(2) and etoposide 750 mg/m(2) i.v. on days -5, -4, -3. Five patients were enrolled and evaluated after tandem transplants 4 weeks apart. All patients had pleural-based and lung parenchymal metastasis, one or two prior surgeries and two or more courses of prior cisplatin-based chemotherapy regimens. Chemotherapy was well tolerated, although grade IV hematological toxicity occurred in all patients. Progression-free survival following HDC ranged from 3.5 to 16.5 months. One patient maintained a CR for 12.8 months, then died from an unrelated cause. With a minimum of 2 years follow-up for all patients, three of five patients remain alive at 26+, 36+, and 49+ months. High-dose carboplatin and etoposide in relapsed thymoma is feasible with acceptable toxicity, however, these limited data do not appear superior to standard-dose salvage therapy.