Clinical trial of post-chemotherapy consolidation thoracic radiotherapy for extensive-stage small cell lung cancer.

Abstract

To define the rate of development of symptomatic chest failures in extensive stage small cell lung cancer (ES-SCLC) after undergoing post-chemotherapy chest radiotherapy (RT). Patients had ES-SCLC, attained an objective response to chemotherapy and signed study consent. Target accrual was 33 patients. Patients were offered prophylactic cranial irradiation (PCI) as per department policy. PCI (25 Gy/10 fractions) and chest RT (40 Gy/15 fractions) were given simultaneously 4-8 weeks after chemotherapy completion. Thoracic target volume was the post-chemotherapy residual chest disease plus margin. Patients were evaluated for RT toxicities, local control, disease-free and overall survival. Thirty-two patients were evaluable. Twenty-nine patients completed RT without delay. There were 4 complete responses and 28 partial responses to chemotherapy. All study patients received PCI. Maximal acute RT toxicity was grade 2 esophagitis (18 patients). There were no RT-related deaths. Median time to disease progression and overall survival were 4.2 and 8.3 months, respectively (median follow-up=21.8 months). Of 16 chest recurrences, 7 were in the irradiated region and 5 were symptomatic. Post-chemotherapy consolidation chest RT for ES-SCLC patients on this trial was well tolerated and associated with symptomatic chest recurrences in only 5/32 treated patients.