Comparison of once daily radiotherapy to 60 Gy and twice daily radiotherapy to 45 Gy for limited stage small-cell lung cancer

BACKGROUND This study was designed to compare toxicities, disease control, and survival outcomes for limited disease small-cell lung cancer (LD-SCLC) treated with once daily (QD) versus twice daily (BID) radiotherapy. METHODS All of the patients received four to six cycles of platinum plus etoposide. In the QD group, irradiation was given via conventional radiotherapy with a dose of 60 Gy at 2 Gy per once-daily fraction. In the BID group, the dose was 45 Gy at 1.5 Gy per twice-daily fraction. RESULTS Data from a total of 143 LD-SCLC patients treated at the Shandong Cancer Hospital & Institute were retrospectively analyzed. Statistically significant differences were found in the rates of both grade 2 or higher esophagitis (P = 0.036) and pneumonitis (P = 0.043) between QD and BID groups, respectively. Grade 3 esophagitis occurred in 6% of patients receiving QD and 19% of those receiving BID therapy. The median overall survival (OS) of all patients was 30.4 months: 29.5 months for QD therapy, and 31.4 months for BID therapy. The two-year OS rate was 43.3% for QD therapy, and 48.8% for BID therapy. The two-year locoregional recurrence-free survival (LRFS) rate was 45% versus 63.4% for the QD group versus the BID group, respectively. CONCLUSIONS Pneumonitis was more common in the QD group, and esophagitis was more common in the BID group. Although there were no significant differences in OS and LRFS between the QD and BID groups, there was a trend toward improved local control in the BID group.