A nationwide survey of radiation oncologists showed a decline in the use of prophylactic cranial irradiation (PCI) for extensive-stage small cell lung cancer (ES-SCLC) after the release of phase 3 study results by Takahashi et al.
The recent study by Toshiaki Takahashi, MD, and colleagues (Lancet Oncol. 2017;18[5]:663-71) demonstrated no overall survival benefit when comparing active magnetic resonance imaging surveillance with PCI in patients with ES-SCLC. The results challenged the formerly accepted belief of the benefit of PCI for patients with ES-SCLC.
“We conducted a nationwide survey study of radiation oncologists to assess changes in the use of PCI for patients with ES-SCLC following publication of the trial by Takahashi et al.,” wrote Olsi Gjyshi, MD, PhD, of the University of Texas MD Anderson Cancer Center, Houston, and colleagues. The findings were reported in a research letter published in JAMA Network Open.
Dr. Gjyshi and colleagues distributed the anonymous survey to 3,851 United States–based radiation oncologists registered with the American Society for Radiation Oncology (ASTRO). In total, 487 members (12.6%) completed the survey.
After analysis, the researchers found that 72% of respondents regularly offered PCI to patients before the publication of the study by Takahashi et al., while only 44% do so currently (difference, 28%; 95% confidence interval, 25%-31%; P less than .001).
With respect to radiation oncologists in private versus academic settings, no significant difference in practice patterns was observed (P = .71).
“Regression analysis showed no difference in likelihood of offering PCI based on practice setting, location, or size; volume of patients treated for lung cancer; or years in practice,” the researchers wrote.
In respondents unaware of the Takahashi et al. study, 85% continued to propose PCI, which was greater than those aware of the trial (odds ratio, 0.11; 95% CI, 0.04-0.32; P less than .001).
The researchers acknowledged a key limitation of the study was that radiation oncologists familiar with the study by Dr. Takahashi and colleagues may have been more apt to respond to the survey. As a result, participation bias could have influenced the results.
“These results highlight the continued lack of consensus for PCI in SCLC and support ongoing investigations,” they concluded.
No funding sources were reported. One co-author reported financial affiliations with Novocure, Inc. The other authors reported no conflicts of interest.
SOURCE: Gjyshi O et al. JAMA Netw Open. 2019 Aug 14. doi: 10.1001/jamanetworkopen.2019.9135.