Randomized Phase II Study Comparing Prophylactic Cranial Irradiation Alone to Prophylactic Cranial Irradiation and Consolidative Extracranial Irradiation for Extensive-Disease Small Cell Lung Cancer (ED SCLC): NRG Oncology RTOG 0937. J Thorac Oncol 2017 Oct;12(10):1561-1570
Date
06/27/2017Pubmed ID
28648948Pubmed Central ID
PMC5610652DOI
10.1016/j.jtho.2017.06.015Scopus ID
2-s2.0-85027876406 (requires institutional sign-in at Scopus site) 109 CitationsAbstract
INTRODUCTION: NRG Oncology RTOG 0937 is a randomized phase II trial evaluating 1-year overall survival (OS) with prophylactic cranial irradiation (PCI) or PCI plus consolidative radiation therapy (PCI+cRT) to intrathoracic disease and extracranial metastases for extensive-disease SCLC.
METHODS: Patients with one to four extracranial metastases were eligible after a complete response or partial response to chemotherapy. Randomization was to PCI or PCI+cRT to the thorax and metastases. Original stratification included partial response versus complete response after chemotherapy and one versus two to four metastases; age younger than 65 years versus 65 years or older was added after an observed imbalance. PCI consisted of 25 Gy in 10 fractions. cRT consisted of 45 Gy in 15 fractions. To detect an improvement in OS from 30% to 45% with a 34% hazard reduction (hazard ratio = 0.66) under a 0.1 type 1 error (one sided) and 80% power, 154 patients were required.
RESULTS: A total of 97 patients were randomized between March 2010 and February 2015. Eleven patients were ineligible (nine in the PCI group and two in the PCI+cRT group), leaving 42 randomized to receive PCI and 44 to receive PCI+cRT. At planned interim analysis, the study crossed the futility boundary for OS and was closed before meeting the accrual target. Median follow-up was 9 months. The 1-year OS was not different between the groups: 60.1% (95% confidence interval [CI]: 41.2-74.7) for PCI and 50.8% (95% CI: 34.0-65.3) for PCI+cRT (p = 0.21). The 3- and 12-month rates of progression were 53.3% and 79.6% for PCI and 14.5% and 75% for PCI+cRT, respectively. Time to progression favored PCI+cRT (hazard ratio = 0.53, 95% CI: 0.32-0.87, p = 0.01). One patient in each arm had grade 4 therapy-related toxicity and one had grade 5 therapy-related pneumonitis with PCI+cRT.
CONCLUSIONS: OS exceeded predictions for both arms. cRT delayed progression but did not improve 1-year OS.
Author List
Gore EM, Hu C, Sun AY, Grimm DF, Ramalingam SS, Dunlap NE, Higgins KA, Werner-Wasik M, Allen AM, Iyengar P, Videtic GMM, Hales RK, McGarry RC, Urbanic JJ, Pu AT, Johnstone CA, Stieber VW, Paulus R, Bradley JDAuthors
Elizabeth M. Gore MD Professor in the Radiation Oncology department at Medical College of WisconsinCandice A. Johnstone MD, MPH Professor in the Radiation Oncology department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
AdultAged
Aged, 80 and over
Brain Neoplasms
Cranial Irradiation
Female
Humans
Lung Neoplasms
Male
Middle Aged
Small Cell Lung Carcinoma
Survival Rate