Purpose: This was a randomized phase III study to test the schedule dependency of etoposide given as a conventional 3-day intravenous (IV) regimen versus a prolonged 21-day oral regimen for extensive-stage small-cell lung cancer (SCLC). Both regimens contained IV cisplatin. The objectives were to compare survival (primary end point) and to establish response rates, failure-free survival, and toxicity (secondary end points).
Patients and methods: Patients with untreated measurable or assessable disease and normal organ function were eligible. Randomization was stratified according to performance status 0 versus 1 or 2. Treatment consisted of etoposide 130 mg/m2/d IV for 3 days and cisplatin 25 mg/m2/d IV for 3 days every 21 days for eight courses (schedule 1) versus etoposide 50 mg/m2/d orally for 21 days and cisplatin 33 mg/m2/d IV for 3 days every 28 days for six courses (schedule 2). In 1990, bioavailability of oral etoposide was assumed to be 50%, and the study was designed to deliver the same total doses of etoposide and cisplatin on both regimens over 24 weeks without the use of growth factors.
Results: Between December 1990 and October 1993, 306 eligible patients were entered. Of these, 69% were male and 66% were > or = 60 years of age; 21% had a performance status of 0, 47% a performance status of 1, and 32% a performance status of 2; 156 were randomized to receive schedule 1 and 150 to receive schedule 2. Overall median survival estimates were 9.5 and 9.9 months (difference not significant) for schedule 1 and schedule 2, respectively. The 95% confidence interval (CI) for overall survival, 8 to 11 months, was the same for both schedules, with 126 and 117 deaths on schedule 1 and 2, respectively. Both schedules also resulted in the same median failure-free survival estimate of 7 months (95% CI, 6 to 8 months on either schedule). Complete and partial responses were observed in 15% and 42% of patients on schedule 1 and 14% and 47% on schedule 2, respectively. The overall maximal hematologic toxicities grade 3 and 4 for leukocytes, neutrophils, platelets, and hemoglobin were, respectively, as follows: schedule 1, 62%, 85%, 32%, and 32%; schedule 2, 83%, 83%, 52%, and 53%. Lethal toxicity due to neutropenia and infection occurred in 4% of patients on schedule 1 and 10% on schedule 2 (difference not statistically significant).
Conclusion: The two schedules of etoposide in combination with cisplatin did not result in differences in treatment outcome with respect to tumor response and survival. However, a significantly greater rate of severe or life-threatening hematologic toxicity was noted on the 21-day oral etoposide treatment schedule.