Concurrent Etoposide/Cisplatin Combination Chemotherapy (EP) and Thoracic Radiotherapy after Two Cycles of EP for Limited Stage Small Cell Lung Cancer

Sohn, Hee Jung; Kim, Sang We; Ahn, Jin Hee; Kang, Hye Jin; Park, Sarah; Jung, Heon Nyoung; Suh, Cheol Won; Kim, Woo Kun; Lee, Sang Wook; Choi, Eun Kyung; Lee, Sang Do; Kim, Woo Sung; Kim, Dong Sun; Kim, Won Dong; Lee, Jung Shin

Abstract

Purposes: Although the standard management of limited stage small cell lung cancer is concurrent platinum-based chemotherapy with thoracic radiotherapy (TRT), the optimal timing of the TRT remains controversial. We investigated the feasibility of concurrent chemoradiation for the patients with limited stage small cell lung cancer after 2 cycles of combination chemotherapy with Etoposide/Cisplatin (EP).
MATERIALS AND METHODS
EP consisted of Etoposide 100 mg/m2 on day 1 to 3 and Cisplatin 70 mg/m2 on day 1. Six cycles were given to the responders every 4 weeks. Total 55 Gy (1.8 Gy once-daily or 1.2 Gy twice-daily, 5 days per week) of TRT were given to the patients who showed at least a partial response after 2 cycles of EP. The other patients were treated by the physician's decision. The patients with complete remission were recommended to receive prophylactic cranial irradiation.
RESULTS
Fifty patients were enrolled. Thirty-five (70%) of them showed responses (2 complete remissions and 33 partial remissions) after 2 cycles of EP. Thirty-three of the responders were given TRT starting with the 3rd cycle of EP. The nonresponders were treated with salvage chemotherapy and TRT. After completion of treatment for 50 patients, the overall response rate was 86% (29 complete remissions, 14 partial remissions). One patient (2%) showed stable disease, and 6 (12%) showed a progressive disease. The median progression free survival was 326 days and the median survival time was 410 days. One-, 2-, 3-, 4- and 5-year survival rates were 62%, 24%, 14%, 9% and 6%, respectively. As hematologic toxicities during chemoradiation, 35.1% with grade III/IV neutropenia and 18.9% with grade III/IV thrombocytopenia were noted. Grade II/III radiation pneumonitis and radiation esophagitis were noted in 5/1 and 13/1 patients (15.2%/ 3.0% and 39.4%/3.0%), respectively. One patient died of septicemia during chemoradiation.
CONCLUSION
The concurrent EP and TRT after 2 cycles of EP was feasible in limited stage small cell lung cancer. Further study is required for the indentification of optimum timing of TRT during combination chemotherapy.