A phase I study of split-dose cisplatin and etoposide with concurrent accelerated hyperfractionated thoracic radiotherapy in elderly patients with limited-disease small cell lung cancer

Objective: The optimal treatment for elderly patients with limited-disease small cell lung cancer has not been defined. We therefore performed a Phase I study for split-dose cisplatin plus etoposide combined with early concurrent accelerated hyperfractionated thoracic radiotherapy in elderly (70 years of age or older) patients with limited-disease small cell lung cancer. Methods: Chemotherapy consisted of cisplatin at 20 or 25 mg/m² and etoposide at 80 mg/m², both administered on Days 1-3 of a 28-day cycle. Radiotherapy was initiated at the onset of chemotherapy and administered at a dose of 1.5 Gy twice daily over 3 weeks up to a total dose of 45 Gy. Results: Twelve patients with a median age of 76 years (range, 70-85) were enrolled. Dose-limiting toxicities occurred in two (hyponatremia of Grade 4 or cardiac ischemia of Grade 3) of the six patients treated at dose Level 1 as well as in three (perforation of the sigmoid colon of Grade 3, febrile neutropenia of Grade 3, or hyponatremia of Grade 3) of the six patients treated at dose Level 2. The most frequent non-hematologic adverse events included anorexia, fatigue, esophagitis and pneumonitis, but most of these events were of Grade 1 or 2. Conclusions: The recommended dose for cisplatin and etoposide chemotherapy administered on Days 1-3 was determined to be 20 and 80 mg/m², respectively. Our results indicate that split-dose cisplatin plus etoposide chemotherapy combined with early concurrent accelerated hyperfractionated thoracic radiotherapy is well tolerated by elderly patients with limited-disease small cell lung cancer.