Thoracic irradiation in 3weeks for limited-stage small cell lung cancer: Is twice a day fractionation really needed?

Abstract

Purpose: Many Canadian institutions treat limited-disease small cell lung cancer with 40Gy in 15 fractions delivered once-a-day in 3weeks concomitantly with chemotherapy. This regimen is convenient and seems to be effective. Here, we report and compare with a literature review the outcomes of patients with limited-stage small cell lung cancer treated in our institution with this hypofractionated regimen.

Patients and methods: From January 2004 to December 2012, patients with limited-stage small cell lung cancer treated curatively with platinum-based chemotherapy and concurrent thoracic radiotherapy at a dose of 40Gy in 16 fractions once-a-day were eligible for this review.

Results: Sixty-eight patients fit the analysis criteria, including ten patients with small pleural effusion. The median age was 66years old. After a median follow-up of 77months for those alive, the median survival was 28months. At 3 and 5years respectively, the locoregional control rates were 67 and 64%, while the overall survival rates were 40 and 35%. Prophylaxis cranial irradiation was delivered to 68% of the patients. Grade 2 and 3 acute esophagitis occurred in respectively 49 and 9% of the patients. There was no grade 4 radiation-induced toxicity. All patients, except for one, completed their thoracic irradiation course without interruption.

Conclusion: Once-a-day hypofractionated radiation with concurrent chemotherapy followed by prophylactic cranial irradiation is a practical regimen. Based on our experience and the published literature, it appears to be similarly effective as regimens using twice-daily fractionation in 3weeks, or once-daily in 6 to 7weeks with higher radiotherapy doses. Further prospective comparisons of hypofractionation with the current recommendations are needed.

Keywords: Chimiothérapie concomitante; Concomitant chemoradiation; Dédoublement cellulaire rapide; Hypofractionation; Hypofractionnement; Irradiation panencéphalique prophylaxique; Prophylactic cranial irradiation; Tumor cell rapid doubling time.