The clinicoradiological features and surgical outcomes of primary intracranial fibrosarcoma: a single-institute experience with a systematic review.

Primary intracranial fibrosarcoma (PIF) was a rare tumor with a high relapse rate and dismal survival rate. This study aimed to delineate the clinical characteristics of primary intracranial fibrosarcoma (PIF) and the risk factors for outcomes. We reviewed 15 PIF patients, who underwent surgical treatment at our institution from January 2009 to December 2018. Meanwhile, 36 cases from the prior literature between November 1962 and December 2019 were also retrieved and pooled to identify the risk factors. In our cohort, while cystic component (46.7%), perilesional edema (83.3%), and vascular flow void (66.7%) were commonly observed, no patient was accurately diagnosed. The 2-year relapse-free survival (RFS) and overall survival (OS) were 12.2% and 30.2%, respectively. Based on the pooled data, tumor size (p = 0.006), Ki-67 index (p = 0.004), and radiotherapy dose (p = 0.029) were prognostic factors for RFS in univariate analysis. In the univariate analysis, tumor size (p = 0.002), NGTR (p = 0.049), and high Ki-67 index (p = 0.019) were significant predictors for OS; and further multivariate analysis (n = 18) showed that large tumor size (≥ 5 cm; HR 14.613, p = 0.022) and high Ki-67 index (≥ 30%; HR 5.879, p = 0.020) were the independent risk factors for OS. Due to the rarity and nonspecific clinicoradiological features, the correct diagnosis of PIF before surgery was challenging. The outcomes of PIF were poor, and GTR plus radiotherapy (at least 60 Gy) might benefit to the outcomes and were recommended. Future study with a large cohort was needed to verify our findings.

Primary intracranial fibrosarcoma in a southern sea otter Enhydra lutris nereis.

Southern sea otters Enhydra lutris nereis, a threatened marine mammal species, face numerous environmental and infectious disease challenges in their native habitat of coastal California, USA. However, there are few published cases describing neoplasia in sea otters despite their relatively long life span when cared for in aquarium settings. An 18 yr old neutered male southern sea otter, born and raised in human care, presented with an acute onset of seizures and dull mentation. Magnetic resonance imaging of the head revealed a large, central brain lesion. After no improvement with treatment, euthanasia was elected due to a poor prognosis. Grossly, a poorly demarcated, granular, tan mass expanded the cranial meninges in the longitudinal fissure at the level of the cruciate sulcus and extended into the underlying gray matter and superficial white matter. Histologically, the mass was composed of spindle cells, forming haphazardly arranged interlacing bundles and herringbone patterns, with a high mitotic count, moderate cellular pleomorphism, and prominent vascularization. Neoplastic cells demonstrated positive immunoreactivity for vimentin and negative immunoreactivity for smooth muscle actin, factor VIII-related antigen, S100, melan-A, E-cadherin, desmin, glial fibrillary acidic protein, and cytokeratin AE1/AE3. Based on gross, histologic, and immunohistochemical findings, the mass was most consistent with a primary intracranial fibrosarcoma (PIF). PIFs are a rare neoplasm in both humans and other animals with few reports in the veterinary literature. This is the first recorded case of a PIF in a sea otter.