Outcomes of brain metastasis in high-grade bone and soft tissue sarcoma: An analysis of clinicopathological characteristics and survival data

Brain metastases in sarcoma are exceedingly rare, with few published series documenting ranges from 1% to 8%. This study investigated the outcomes of sarcoma patients with brain metastases using a population-based analysis. This was a retrospective review of 5933 patients with high-grade sarcoma identified from the Surveillance, Epidemiology, and End Results database between 2010 and 2015. Of the eligible 5933 patients, 0.7% (n = 44) had brain metastasis. Kaplan-Meier was used to estimate survival and follow-up (reverse Kaplan-Meier), and a multivariable Cox proportional hazards model analyzed prognostic factors of disease-free survival (DFS). Median (IQR) follow-up of all eligible patients was 28 months (12; 47). Patients who developed brain metastasis had a higher proportion of N1 stage disease (p < 0.001), as well as synchronous metastasis to bones, liver, and lungs compared to those without brain metastasis (all p < 0.001). The median (IQR) DFS with brain metastasis was 6 months (2; 12), and survival with brain metastasis was significantly worse than DFS in patients without brain metastasis (p < 0.001). Among those with brain metastasis only, there was no difference in DFS with respect to sex, race, primary tumor origin, T stage or N stage disease, synchronous metastasis to bone, liver or lung, nor with respect to chemotherapy or radiation for treatment of the primary tumor (all p > 0.05). For sarcoma patients with brain metastasis, the outcomes are poor and do not appear to differ by clinicopathologic factors. However, patients with certain histologies and synchronous metastases may warrant more frequent surveillance as there was an association of brain metastasis with these factors.