Pikis, Stylianos

BACKGROUND: Intraventricular metastases (IVMs) are uncommon, and their optimal management remains debatable. OBJECTIVE: To define the safety and efficacy of stereotactic radiosurgery (SRS) in the treatment of IVMs. METHODS: This retrospective, multicenter study included patients managed with SRS for IVMs. SRS-induced adverse events, local tumor or intracranial progression, and the frequency of new-onset hydrocephalus or leptomeningeal spread were documented. Analyses of variables related to patient neuroimaging or clinical outcomes were also performed. RESULTS: The cohort included 160 patients from 11 centers who underwent SRS for treatment of 1045 intracranial metastases, of which 196 were IVMs. The median survival from SRS was 10 months. Of the 154 patients and 190 IVMs with imaging follow-up, 94 patients (61%) experienced distant intracranial disease progression and 16 IVMs (8.4%) progressed locally. The 12- and 24-month local IVM control rates were 91.4% and 86.1%, respectively. Sixteen (10%) and 27 (17.5%) patients developed hydrocephalus and leptomeningeal dissemination post-SRS, respectively. Adverse radiation effects were documented in 24 patients (15%). Eleven patients (6.9%) died because of intracranial disease progression. CONCLUSION: SRS is an effective treatment option for IVMs, with a local IVM control rate comparable with SRS for parenchymal brain metastases. Leptomeningeal spread and hydrocephalus in patients with IVM occur in a minority of patients, but these patients warrant careful follow-up to detect these changes.

OBJECTIVE Stereotactic radiosurgery (SRS) is an effective treatment for intracranial metastatic disease, but its role in triple-negative breast cancer requires further study. Herein, the authors report overall survival (OS) and local tumor control in a multiinstitutional cohort with triple-negative breast cancer metastases treated with SRS. METHODS Patients treated from 2010 to 2019 at 9 institutions were included in this retrospective study if they had biopsy-proven triple-negative breast cancer with intracranial metastatic lesions treated with SRS. Patients were excluded if they had undergone prior SRS, whole-brain radiation therapy, or resection of the metastatic lesions. A retrospective chart review was conducted to determine OS, local control, and treatment efficacy. RESULTS Sixty-eight patients with 315 treated lesions were assessed. Patients had a median Karnofsky Performance Status of 80 (IQR 70–90) and age of 57 years (IQR 48–67 years). Most treated patients had 5 or fewer intracranial lesions, with 34% of patients having a single lesion. Treated lesions were small, having a median volume owf 0.11 cm3 (IQR 0.03–0.60 cm3). Patients were treated with a median margin dose of 18 Gy (IQR 18–20 Gy) to the median 71% isodose line (IQR 50%–84%). Overall, patients had a 1-year OS of 43% and 2-year OS of 20%. Most patients (88%) were followed until death, by which time local tumor progression had occurred in only 7% of cases. Furthermore, 76% of the lesions demonstrated regression. Tumor volume was correlated with local tumor progression (p = 0.012). SRS was very well tolerated, and only 3 patients (5%) developed symptomatic radiation necrosis. CONCLUSIONS SRS is a safe and efficacious treatment for well-selected patients with triple-negative breast cancer, especially for those with a favorable performance status and small- to moderate-volume metastatic lesions.

Background: Brain metastases (BM) from differentiated thyroid cancer are rare. Stereotactic radiosurgery (SRS) is commonly used for the treatment of BMs; however, the experience with SRS for thyroid cancer BMs remains limited. The goal of this international, multi-centered study was to evaluate the efficacy and safety of SRS for thyroid cancer BMs. Methods: From 10 institutions participating in the International Radiosurgery Research Foundation, we pooled patients with established papillary or follicular thyroid cancer diagnosis who underwent SRS for histologically confirmed or radiologically suspected BMs. We investigated patient overall survival (OS), local tumor control, and adverse radiation events (AREs). Results: We studied 42 (52% men) patients who underwent SRS for 122 papillary (83%) or follicular (17%) thyroid cancer BMs. The mean age at SRS was 59.86 ± 12.69 years. The mean latency from thyroid cancer diagnosis to SRS for BMs was 89.05 ± 105.49 months. The median number of BMs per patient was 2 (range: 1–10 BMs). The median SRS treatment volume was 0.79 cm 3 (range: 0.003–38.18 cm 3 ), and the median SRS prescription dose was 20 Gy (range: 8–24 Gy). The median survival after SRS for BMs was 14 months (range: 3–58 months). The OS was significantly shorter in patients harboring ≥2 BMs, when compared with patients with one BM (Log-rank = 5.452, p = 0.02). Two or more BMs (odds ratio [OR] = 3.688; confidence interval [CI]: 1.143–11.904; p = 0.03) and lower Karnofsky performance score at the time of SRS (OR = 0.807; CI: 0.689–0.945; p = 0.008) were associated with shorter OS. During post-SRS imaging follow-up of 25.21 ± 30.49 months, local failure (progression and/or radiation necrosis) of BMs treated with SRS was documented in five (4%) BMs at 7.2 ± 7.3 months after the SRS. At the last imaging follow-up, the majority of patients with available imaging data had stable intracranial disease (33%) or achieved complete (26%) or partial (24%) response. There were no clinical AREs. Post-SRS peritumoral T2/fluid attenuated inversion recovery signal hyperintensity was noted in 7% BMs. Conclusion: The SRS allows durable local control of papillary and follicular thyroid cancer BMs in the vast majority of patients. Higher number of BMs and worse functional status at the time of SRS are associated with shorter OS in patients with thyroid cancer BMs. The SRS is safe and is associated with a low risk of AREs.