Molecular cytogenetic analysis of a gliosarcoma with osseous metaplasia

The clinical, radiological, and immunohistochemical characteristics and outcomes of primary intracranial gliosarcoma: a retrospective single-centre study

Primary intracranial gliosarcoma is a rare malignant brain tumour, and the most effective treatment for gliosarcoma remains unclear. This study aimed to identify risk factors for progression-free survival (PFS) and overall survival (OS) in these cases. This retrospective single-centre study evaluated 103 patients (median age, 51 years; 67 men [65%]) with primary intracranial gliosarcoma between 2006 and 2017. Treatments included surgery (GTR, 63 patients; STR, 39 patients; biopsy, 1 patient), radiotherapy (adjuvant, 76 patients; exclusive treatment, 1 patient), and chemotherapy (adjuvant temozolomide, 52 patients; adjuvant nimustine/teniposide, 19 patients; adjuvant bevacizumab, 1 patient; exclusive nimustine/teniposide treatment, 1 patient). The median OS was 13.3 months, and the median PFS was 9.1 months. In the multivariate analyses, the poor prognostic factors were ependymal lining enhancement of the lateral ventricle (PFS, HR 2.406, p = 0.005; OS, HR 2.946, p = 0.009) and enhancement in the motor functional cortex (PFS, HR 2.892, p = 0.002; OS, HR 2.639, p = 0.009). Good OS was predicted by adjuvant radiotherapy alone (HR 0.071, p < 0.001), adjuvant temozolomide-based chemotherapy alone (HR 0.063, p = 0.005), adjuvant temozolomide-based chemotherapy with concurrent radiotherapy (HR 0.056, p < 0.001), and salvage surgery at recurrence (HR 0.449, p = 0.031). The present study revealed that, in patients with primary intracranial gliosarcoma, enhancement in the functional motor cortex and ependymal lining enhancement of the lateral ventricle were both poor prognostic factors. Survival was optimized in cases treated using maximal safe resection followed by adjuvant temozolomide-based chemotherapy with concurrent radiotherapy. Furthermore, salvage surgery provided meaningful therapeutic benefits for recurrent gliosarcoma.

Clinical Characteristics of Gliosarcoma and Outcomes From Standardized Treatment Relative to Conventional Glioblastoma

Background: Gliosarcoma (GS) is a rare histopathologic variant of glioblastoma (GBM) characterized by a biphasic growth pattern consisting of both glial and sarcomatous components. Reports regarding its relative prognosis compared to conventional GBM are conflicting and although GS is treated as conventional GBM, supporting evidence is lacking. The aim of this study was to characterize demographic trends, clinical outcomes and prognostic variables of GS patients receiving standardized therapy and compare these to conventional GBM. Methods: Six hundred and eighty GBM patients, treated with maximal safe resection followed by radiotherapy with concomitant and adjuvant temozolomide at a single institution, were retrospectively reevaluated by reviewing histopathological records and tumor tissue for identification of GS patients. Clinico-pathological- and tumor growth characteristics were obtained via assessment of medical records and imaging analysis. Kaplan-Meier survival estimates were compared with log-rank testing, while Cox-regression modeling was tested for prognostic factors in GS patients. Results: The cohort included 26 primary gliosarcoma (PGS) patients (3.8%) and 7 secondary gliosarcoma (SGS) patients (1.0%). Compared to conventional GBM tumors, PGS tumors were significantly more often MGMT-unmethylated (73.9%) and located in the temporal lobe (57.7%). GS tumors often presented dural contact, while extracranial metastasis was only found in 1 patient. No significant differences were found between PGS and conventional GBM in progression-free-survival (6.8 and 7.6 months, respectively, p = 0.105) and in overall survival (13.4 and 15.7 months, respectively, p = 0.201). Survival following recurrence was not significantly different between PGS, SGS, and GBM. Temporal tumor location and MGMT status were found associated with PGS survival (p = 0.036 and p = 0.022, respectively). Conclusion: Despite histopathological and location difference between GS and GBM tumors, the patients present similar survival outcome from standardized treatment. These findings support continued practice of radiation and temozolomide for GS patients.

Multiple chromosomal monosomies are characteristic of giant cell ependymoma

Giant cell ependymoma, a rare ependymoma subtype, was recently recognized as a separate diagnostic entity with variations both in malignant potential and course of disease. We analyzed the first supratentorial giant cell ependymoma using G-band karyotyping, DNA ploidy analysis, and array comparative genomic hybridization. The tumor was hypodiploid, and the karyotype showed multiple monosomies. This novel cytogenetic pattern seems specific for giant cell ependymoma as the only previous cytogenetic analysis of a giant cell ependymoma found similar monosomies. We were also able to analyze cytogenetically the subsequent recurrent tumor, phenotypically an anaplastic ependymoma, allowing a first insight into the genetic events involved in disease progression.