Brain Metastases from Adult Sarcomas: A Retrospective Cohort Study from the Hellenic Group of Sarcomas and Rare Cancers (HGSRC)

Brain metastases are rare events in patients with sarcoma and the available information is relatively limited. We retrospectively reviewed medical records of patients with sarcoma who developed brain metastases between April 2010 and April 2020 in six centers. Thirty-four adult patients were included with a median age at brain metastases diagnosis of 55.5 years (range, 18-75). The primary sarcomas originated either from soft tissue (n = 27) or bone (n = 7) and the most common subtypes were leiomyosarcoma (n = 8), Ewing sarcoma/peripheral neuroectodermal tumor (PNET) (n = 7) and osteosarcoma (n = 3). Most primary tumors were of high grade and located mainly in the extremities (n = 18). The vast majority of patients at the time of brain metastasis diagnosis already had extracranial metastatic disease (n = 26). The median time from sarcoma diagnosis to cerebral metastasis diagnosis was 16 months (range, 1-136). Treatment modalities for brain metastatic disease included whole-brain radiation therapy (WBRT) (n = 22), chemotherapy (n = 17), exclusive palliative care (n = 5), surgery (n = 9), targeted therapy (n = 6) or stereotactic radiosurgery (n = 2). Most patients experienced a progression of brain metastases (n = 11). The median overall survival from brain metastasis diagnosis was 3 months (range, 0-80). OS was significantly influenced by time-to-brain metastases (p = 0.041), WBRT (p = 0.018), surgery (p = 0.002) and chemotherapy (p = 0.006). In a multivariate analysis, only the localization of the primary (p = 0.047) and WBRT (p = 0.038) were associated with survival with statistical significance. Patients with sarcoma brain metastases have a particularly poor prognosis and an appropriate therapeutic approach is yet to be defined.