Rapid spontaneous malignant progression of supratentorial tanycytic ependymoma with sarcomatous features – “Ependymosarcoma”

Ependymosarcoma harboring C11orf95:RELA fusion transcript: Report of two cases and review of the literature

Ependymoma is a relatively rare glial tumor of the central nervous system that arise from the cells lining the ventricles and central canal of the spinal cord. Ependymosarcoma (ES) is a newly introduced tumor entity of uncertain prognosis characterized by a rare phenomenon of a malignant mesenchymal transition arising within an ependymoma. ESs are surgically challenging tumors for diagnosis and therapy with a high incidence of morbidity and mortality. Here, we report two diagnostically challenging cases of primary ES in a 25-year-old female and a 17-year-old male. Both the cases presented with progressive and sequential neurological deficits over a period of five to eight months, and histological examination revealed a biphasic gliomesenchymal architecture comprised of anaplastic ependymomatous and sarcomatous components. Molecular genetic analysis revealed the presence of type 1 C11orf95:RELA fusion transcript. To date, 22 cases of ES have been reported in the literature, and only one case harbored type 1 C11orf95:RELA fusion transcript.

Risk factors for the recurrence of world health organization grade Ⅱ ependymomas of spinal cord in adults after microsurgical resections: A retrospective study of 118 patients in a single center

OBJECTIVE

To identify the risk factors for recurrence of World Health Organization (WHO) grade Ⅱ ependymomas of spinal cord in adults after microsurgical resections.

PATIENTS AND METHODS

A total of 118 adult patients diagnosed with WHO grade Ⅱ ependymomas of spinal cord at west china hospital from January 2010 to December 2016 were reviewed retrospectively. To identify the risk factors for recurrence, we performed univariate analyses and multivariate logistic regression analyses successively.

RESULTS

Twelve patients had a recurrence with a median recurrence time of 30 months [inter-quartile range (IQR) 23.5-75.5 months]. Univariate analysis showed that age (p = 0.030), STR (p < 0.001), index of Ki-67 (p = 0.004), and Vimentin (+, p = 0.004) were associated with postoperative recurrence of ependymomas of spinal cord in adults, while univariate analysis showed that only STR [odds ratio (OR) = 18.838, 95 % confidence interval (CI): 3.068-115.673; p = 0.002], index of Ki-67 (OR = 1.381, 95 % CI: 1.021-1.868; p = 0.036), Vimentin (+; OR = 6.706, 95 % CI: 1.218-36.928; p = 0.029) were independent risk factors for recurrence.

CONCLUSIONS

The recurrence rate of WHO grade Ⅱ ependymomas of spinal cord in adults was about 13.6 %. Subtotal resection is a critical risk factor for recurrence. A high index of Ki-67 is another independent risk factor for recurrence. Positive Vimentin may also play a role in this process. GTR is very important to prevent recurrence after operation if it is safe to conduct. In cases with higher index Ki-67 and Vimentin (+), close follow-ups are necessary.

TERT Promoter Mutations but not the Alternative Lengthening of Telomeres Phenotype Are Present in a Subset of Ependymomas and Are Associated With Adult Onset and Progression to Ependymosarcoma

Genetic signatures related to telomere maintenance have emerged as powerful classifiers among CNS tumors. These include the alternative lengthening of telomeres (ALT) phenotype associated with mutations in the ATRX and DAXX genes and recurrent point mutations in the TERT gene promoter. We investigated a patient cohort covering the entire spectrum of childhood and adult ependymomas (n = 128), including subependymomas and myxopapillary ependymomas, for the presence of TERT promoter mutations, for loss of ATRX or DAXX expression by immunohistochemistry (as surrogates as underlying gene mutations), and for the ALT phenotype by fluorescence in situ hybridization (FISH). TERT promoter mutations were identified in 9/120 (7%) of tumors, all of which were conventional ependymomas occurring in adults. TERT promoter mutations were associated with older age and intracranial localization. Remarkably, 2 of these tumors progressed to ependymosarcoma upon recurrence. No tumors displayed an ALT phenotype by FISH or were ATRX or DAXX deficient by immunohistochemistry. In sum, TERT promoter mutations are present in a subset of mostly intracranial conventional ependymomas in adults and may be relevant for the uncommon progression to ependymosarcoma. Loss of ATRX immunoreactivity is a useful marker to rule out ependymoma in specific diagnostic settings.

Ependymosarcoma with eosinophilic granular cells

Ependymosarcoma is a new entity of malignant gliomas composed of ependymal and sarcomatous components. Were port a rare case of ependymosarcoma with eosinophlic cells which occurred to the right trigon of the lateral ventricle.A 62-year-old man complained of headaches over a 2-month period. A hard, gray mass was found in the right trigon of the lateral ventricle during the operation.Although he received radiation and chemotherapy, the patient died due to tumor disseminating through the whole brain within 7 months after the operation. The histological examination revealed that the anaplastic glial components intermingled with the sarcomatous components. Immunohistochemically, sarcomatous cells were positive for α smooth muscle actin and desmin. However, anaplasticglial cells were not positive for these markers. In addition, Masson trichrome stain showed a plethora of collagen fibers between sarcomatous cells, but no collagen fibers were produced by the glial tumor cells. Solid focal papillary lesions of the glial tumor showed dot-like epithelial membrane antigen and diffuse cytoplasmic D2-40 immunoreactivity. Based on the above findings, these anaplastic glial tumor cells should show focal ependymal differentiation, and sarcomatous cells show myofibroblastic differentiation. In addition, almost 10%of the tumor cells in the neoplasm showed bright eosinophilic granules in the cytoplasm. These cytoplasmic eosinophilic granules and bundles were negative on PAS staining. Intracytoplasmic eosinophilic granules of tumor cells were strongly positive for αB-crystallin, HSP 27 and GFAP, respectively. These findings suggest that the clinicopathological characteristics of the present case should be consistent with the criterion of ependymosarcoma by Rodriguez et al.

Identification of t(1;19)(q12;p13) and ploidy changes in an ependymosarcoma: a cytogenetic evaluation

Gliosarcoma, a recognized subtype of glioblastoma, is a biphasic tumor exhibiting distinct glial and sarcomatous components. Ependymosarcomas are rarer, biphasic ependymal tumors exhibiting sarcomatous change. Genetic abnormalities associated with this curious phenotype are not well understood. We are presenting the first karyotype of ependymosarcoma with identification of a clonal t(1;19)(q12;p13). Fluorescence in situ hybridization (FISH) was performed with a probe set targeting 1q23 and 19p13.3. Although the tumor did not show evidence of t(1;19)(q23;p13.3) by FISH, increased ploidy was a feature of the sarcomatous component. On clinical follow-up the patient is doing well without evidence of recurrence 55 months after initial resection, and postoperative treatment with irradiation and temozolomide. The significance of the genetic alterations we describe associated with sarcomatoid change in ependymal neoplasms, and ultimately their prognostic relevance, merits further study.