Shin, Kee‐Young

PURPOSE Stereotactic radiation (SRS/SRT) as opposed to whole-brain radiation (WBRT) represents the standard of care for patients with a limited number of brain metastases given the relatively favorable toxicity profile associated with stereotactic treatment. However, in patients with small cell lung cancer (SCLC), WBRT remains standard because of a lack of prospective data supporting SRS/SRT and concerns related to intracranial progression and neurologic death when WBRT is omitted. We conducted a single-arm, multicenter, phase II trial of SRS/SRT in patients with SCLC and 1-10 brain metastases to assess neurologic death rates relative to historical controls managed with WBRT (ClinicalTrials.gov identifier: NCT03391362 ). METHODS Patients were eligible if they had SCLC or an extrathoracic small cell primary and 1-10 brain metastases. Previous brain-directed radiation including prophylactic cranial irradiation was not permitted. Neurologic death was defined as marked, progressive, radiographic brain progression accompanied by corresponding neurologic symptomatology without systemic disease progression or systemic symptoms of a life-threatening nature. Close imaging-based surveillance of the brain post-SRS/SRT was used. RESULTS Between February 2018 and April 2023, 100 patients were enrolled. The median number of brain metastases was 2 (IQR, 1-4; range, 1-10). The median overall survival was 10.2 months; only 22% of patients required salvage WBRT. In total, 20 neurologic deaths were observed, relative to 64 non-neurologic deaths. The neurologic death rate at 1 year was 11.0% (95% CI, 5.8 to 18.1); the historical rate in patients managed with WBRT was 17.5%. CONCLUSION Our prospective, multi-institutional study demonstrated low rates of neurologic death when SRS/SRT as opposed to WBRT is used in patients with SCLC and 1-10 brain metastases who are surveilled closely post-treatment, supporting the utility of stereotactic approaches in this population.

2011 Background: Radiation therapy forms the mainstay of management for patients with brain metastases. Published randomized trials have found improved quality of life with stereotactic radiation (SRS/SRT) over whole brain radiation (WBRT) in patients with ≤ 4 brain metastases; comparative trials in patients with >4 brain metastases are lacking. In addition, prior randomized trials have demonstrated the superiority of hippocampal avoidance WBRT (HA-WBRT) over traditional WBRT, but no study has compared SRS/SRT to HA-WBRT. Accordingly, we conducted a multicenter, phase 3 randomized trial comparing SRS/SRT to HA-WBRT in patients with 5-20 brain metastases. Methods: Eligible patients were age 18-80 with 5-20 brain metastases secondary to a solid primary other than small cell lung cancer, were naïve to prior brain-directed radiation, and lacked leptomeningeal disease. The primary endpoint was the average of patient-reported symptom severity and interference over the first six months post-baseline relative to baseline, using the MD Anderson Symptom Inventory–Brain Tumor (MDASI-BT) module, a validated instrument assessing 22 symptoms and 6 interference measures integral to quality of life, each scored 0-10 with higher scores indicating greater symptomatology/interference in function. The target effect size was a symptom severity of 0.70, corresponding to 50% of the observed difference between patients with a good (90-100) versus poor (≤80) Karnofsky performance status; with 80% power and a two-sided alpha of 0.05, 196 patients were required. Results: Between 4/2017-5/2024, 196 patients enrolled, 98 in each arm. The median number of brain metastases was 14 (IQR 11-18); 25% of patients underwent prior neurosurgical resection. Baseline mean MDASI-BT symptom severity scores were 2.2 (SRS/SRT arm) and 1.9 (HA-WBRT arm), p=0.20; respective interference scores were 3.5 and 3.2 (p=0.40). The average of weighted post-baseline severity and interference scores relative to baseline indicated lower symptomatology/inference in the SRS/SRT arm, meeting the primary endpoint of the study (difference between SRS/SRT and HA-WBRT: -1.06, p<0.001). Averaged post-baseline symptom severity scores minus baseline were -0.03 and 0.59 in the SRS/SRT and HA-WBRT arms, respectively (difference -0.62, with lower symptom severity in the SRS/SRT arm, p<0.001); respective interference estimates were -0.62 and 0.89 (difference -1.50, with lower interference in the SRS/SRT arm, p<0.001). Median survival was 8.3 and 8.5 months in the SRS/SRT and HA-WBRT arms, respectively (p=0.30). Conclusions: This phase 3 randomized trial indicates that patients with 5-20 brain metastases experience fewer symptoms and less interference in function after SRS/SRT as opposed to HA-WBRT, without compromise of survival, supporting SRS/SRT as the standard of care in this population. Clinical trial information: NCT03075072 .