Preliminary results of randomized phase II study of etoposide plus lobaplatin or etoposide plus cisplatin with concurrent thoracic radiotherapy in the treatment of limited-stage small cell lung cancer

The purpose is to compare the clinical efficacy and toxicity of etoposide plus lobaplatin (EL) or etoposide plus cisplatin (EP) with concurrent thoracic radiotherapy during the treatment of limited-stage small cell lung cancer (LS-SCLC). Forty-two patients with LS-SCLC were randomly divided into EL ( n = 19) or EP ( n = 23) regimens combined with thoracic intensity-modulated radiotherapy. The primary endpoint was 1-year progression-free survival (PFS) rate. The 1-, 2-, and 3-year PFS rates in the EL and EP cohorts were 50.8, 38.1, and 12.7%; and 56.5, 43.5, and 29.0%, respectively ( P = 0.527), whereas the 1-, 2-, and 3-year overall survival (OS) rates were 72.2, 52.5, and 43.8%; and 73.9, 48.4, and 48.4%, respectively ( P = 0.923). The hematological toxicities were similar in two cohorts. However, gastrointestinal reactions were more severe in the EP group. The incidence of nausea and vomiting in EL and EP cohorts were 31.6% vs. 73.9% ( P = 0.006) and 20.1% vs. 60.9% ( P = 0.009), respectively. The two cohorts did not show ≥grade 4 radiation esophagitis and ≥grade 3 radiation pneumonitis. The incidence of acute radiation esophagitis in EL group was lower ( P = 0.038), both groups showed a similar incidence of radiation pneumonitis ( P = 1.000). EL or EP chemotherapy with concurrent thoracic radiotherapy showed similar PFS and OS. The EL group showed milder gastrointestinal toxicity and radiation esophagitis. Radiation pneumonitis and hematological toxicity were similar in the two regimens, which can be tolerated by patients.