Stereotactic RT Cuts Neurologic Deaths in SCLC, Brain Mets

Medscape

2 days ago

TOPLINE:
A phase 2 trial found that compared with whole brain radiation (WBRT), stereotactic radiation reduced neurologic deaths in patients with small cell lung cancer (SCLC) and 1-10 brain metastases.
METHODOLOGY:
SCLC carries a high risk for brain metastases and has traditionally been managed with WBRT or prophylactic cranial irradiation. Stereotactic radiosurgery/radiotherapy has become standard for patients with limited brain metastases from other solid tumors, but prospective data are lacking in those with SCLC.
Researchers conducted a multicenter, phase 2 trial of 100 patients (median age, 68 years; 55% women) with SCLC or extrathoracic small cell primaries and 1-10 brain metastases.
Participants received brain-directed stereotactic radiation — 20 Gy in a single fraction for lesions under 2 cm and fractionated schedules (30 Gy in five fractions) when necessary. Grossly resected cavities received 25-30 Gy in five fractions with a simultaneous integrated boost.
The primary endpoint was neurologic death — defined as progressive radiographic brain disease with corresponding neurologic symptoms in the absence of systemic progression. The control group was a historical cohort of 35 patients with 1-6 brain metastases who underwent WBRT between 2008 and 2015.
Secondary endpoints included overall survival, incidence of new brain metastases, leptomeningeal disease, and salvage brain-directed radiation. Median follow-up for survivors was 22 months.
TAKEAWAY:
Twenty neurologic deaths and 64 nonneurologic deaths occurred. The 1-year incidence of neurologic death was 11.0% among patients who received stereotactic radiation vs 17.5% in the WBRT group; 2–year rates were 20.3% and 35.2%, respectively.
Median overall survival was 10.2 months. New brain metastases developed in 61% of patients (1-year estimate, 59.0%). Overall, 39% of the total population received salvage stereotactic radiation, while 22% required salvage WBRT, indicating that 78% avoided WBRT entirely.
Looking at 2-year estimates, leptomeningeal disease occurred in 9% of patients (1-year estimate, 7%), systemic progression in 66% (1-year estimate, 58%), local recurrence in 17% (1-year estimate, 15%), radiographic radiation necrosis in 8% (1-year estimate, 6%), and symptomatic necrosis in 5.4% (1-year estimate, 3%).
IN PRACTICE:
'Our phase 2 trial supports the viability of SRS/SRT [stereotactic radiation] in the management of patients with SCLC and a limited number of brain metastases who are naive to previous brain-directed radiation, including PCI [prophylactic cranial irradiation],' the authors wrote. Ongoing trials comparing stereotactic radiation to hippocampal-sparing WBRT will offer additional insights, the authors noted.
SOURCE:
This study, led by Ayal A. Aizer, MD, MHS, Brigham and Women's Hospital, Dana-Farber Cancer Institute, Boston, was published online in the Journal of Clinical Oncology.
LIMITATIONS:
Limitations included a lack of concurrent WBRT control and reliance on data from a historical cohort from a single institution. The results might not be applicable to patients with more than 10 lesions. Additionally, frequent surveillance and early use of salvage stereotactic radiation mitigated the risk for neurologic death that might have otherwise been seen.
DISCLOSURES:
This study was supported by the Joint Center for Radiation Therapy, Boston. Several authors reported receiving research funding or honoraria or having ties with various sources. Additional disclosures are noted in the original article.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.