Survival and local control rates for limited stage small-cell lung cancer patients treated with either once-daily or twice-daily thoracic radiation plus cisplatin(Drug information on cisplatin) (Platinol) and etoposide(Drug information on etoposide) (VePesid) are substantially better than with previously reported treatment regimens, preliminary results of RTOG 88-15 indicate.
The 358 eligible patients were randomized to one of two arms of the study. In one arm, patients received thoracic irradiation once a day to a total dose of 45 Gy in 5 weeks.
In the other arm, patients received 1.5 Gy twice daily to a total dose of 45 Gy in 3 weeks.
All patients underwent the same chemotherapy regimen of four cycles of cisplatin (60 mg/m² on day one of radiation treatment) and etoposide (120 mg/m² on days one, two, and three). This regimen was repeated at 21-day intervals.
Patients with complete response underwent prophylactic cranial irradiation (25 Gy given in 10 fractions over 2 weeks).
The median survival for patients treated twice a day with radiation was 20.3 months, said Dr. Wally Curran, an author of the study. It was 18.6 months for patients treated once a day, he said. That compares to about 14 months for patients who undergo standard treatment. The local failure rate was 61% for patients treated daily, and 48% for those treated twice daily.
According to Dr. Curran, 15% of patients treated daily had grade 3 or worse toxicities, compared with 30% for those treated twice daily.
"Because we observed better local control and survival rates, RTOG is continuing to pursue twice-daily treatment as a schedule for limited stage small-cell lung cancer patients," said Dr. Curran. RTOG has two limited stage small-cell lung cancer trials open: RTOG 93-07 and RTOG 93-12.
RTOG 88-15 was an intergroup trial, coordinated by the Eastern Cooperative Oncology Group. RTOG contributed about one-third of the patients to the study.
The results of RTOG 88-15 were presented at the recent annual meeting of the American Society for Therapeutic Radiology and Oncology.