This Phase II randomized study is to determine whether once-daily simultaneous modulated accelerated thoracic radiotherapy (RT) resulted in better survival than twice-daily RT for patients with limited-stage small-cell lung cancer (LD-SCLC).

This Phase II randomized study is to determine whether once-daily (qd)simultaneous modulated accelerated thoracic radiotherapy resulted in better survival than twice-daily(bid) RT for patients with limited-stage small-cell lung cancer (LD-SCLC).

All patients receive four to six cycles of etoposide and cisplatin (EP) every 3 weeks. Thoracic RT is initiated with cycle 1-3 of chemotherapy. Qd RT includes the delivery of 65 Gy in 26 fractions delivered on weekdays for a total of 33 days. Bid RT includes the delivery of 45 Gy in 30 fractions delivered on weekdays for a total of 19 days. After the chest RT and the last cycle of EP, prophylactic cranial irradiation is administered to those patients with a complete or partial remission.

Inclusion Criteria:

• Pathologic confirmation of SCLC. Imaging studies' confirmation of limited stage.
• No previous chest radiotherapy, chemotherapy or biotherapy.
• Patients have measurable or evaluable lesions based on the Response Evaluation Criteria in Solid Tumors (RECIST) criteria.
• White blood cell count ≥4×109 /L, platelet count≥100×109 /L, hemoglobin ≥100 g /L; serum creatinine and total bilirubin 1.5 times or less the upper limits of normal (ULN), aspartate aminotransferase two times or less the ULN.
• Eastern Cooperative Oncology Group (ECOG) performance status 0-1.
• Weight loss ≤10% within the past 3 months.
• Forced expiratory volume in 1 s >1 L.

Exclusion Criteria:

• Previous or recent another malignancy.
• A myocardial infarction within 6 months or had uncontrolled congestive heart failure, uncontrolled arrhythmia.
• Malignant pleural or pericardial effusion.
• Pregnant or Lactating.
• Weight loss >10% within the past 3 months.
• Drug addiction, long-term alcohol abuse and AIDS patients.