Gliosarcoma | |
---|---|
Other names | Sarcomatous glioblastoma [1] |
Micrograph showing a gliosarcoma. Elastic van Gieson's stain. | |
Specialty | Neuro-oncology |
Usual onset | Between 40 and 60 years old [2] |
Prognosis | Five-year survival rate: 5.6% [2] |
Frequency | ~215 new diagnoses per year (United States) [2] |
Gliosarcoma is a rare type of glioma, a cancer of the brain that comes from glial, or supportive, brain cells, as opposed to the neural brain cells. Gliosarcoma is a malignant cancer, and is defined as a glioblastoma consisting of gliomatous and sarcomatous components. [3] Primary gliosarcoma (PGS) is classified as a grade IV tumor and a subtype of glioblastoma multiforme in the 2007 World Health Organization classification system (GBM). [4] Because of a lack of specific and clear diagnostic criteria, the word "gliosarcoma" was frequently used to refer to glial tumours with mesenchymal properties, [5] such as the ability to make collagen and reticulin. [6]
It is estimated that approximately 2.1% of all glioblastomas are gliosarcomas. Although most gliomas rarely show metastases outside the cerebrum, gliosarcomas have a propensity to do so, most commonly spreading through the blood to the lungs, and also liver and lymph nodes. [7]
They most commonly present in the temporal lobe [8] [9] and frontal lobe. [10]
Early reports claimed that the hyperplastic blood vessels that are frequently present in high grade gliomas underwent neoplastic change to become the sarcomatous components. [6] Feigin's early reports components of perivascular sarcomatous and hyperplastic arteries in gliosarcoma offered evidence for the "collision tumor" hypothesis. [11] Also, Studies demonstrating the sarcomatous component's histological sensitivity to markers of vascular endothelium such factor CD34, von Willebrand factor, and VIII supported this theory. [12] [13] [14] An alternative view that has recently gained support suggests that both gliosarcoma components have a monoclonal origin, with the sarcomatous component deriving from abnormal differentiation of malignant gliomal mesenchyma. First, gliomatous and sarcomatous components were shown to have similar p53 alterations by Biernat and colleagues. [15] In both tumor regions, Reis and colleagues found similar nuclear accumulation of p53, deletion of p16, mutations of PTEN,and amplifications of CDK4. [16] Other scientists then noted that both gliosarcoma components had similar genetic changes and chromosomal abnormalities of the kind often seen in GBM. [17] [18]
Gliosarcoma is rare; incidence ranges from 1.8 to 2.8 percent lower than that of GBMs. [19] PGS affects persons in their 6th to 7th years of life, and it is much more frequent in males than in females (with 1.4-1.8:1 ratio). [19] Depending on where the tumor is located, the reported presenting signs and symptoms, such as aphasia, headaches, hemiparesis, seizures, and cognitive loss, are similar with those of a fast developing intracranial tumor. Many researchers have come to the conclusion that these tumors are clinically identical to GBM due to their clinical similarities. [20]
On CT imaging, the lesions might show as Well-defined high-density lesion edges and homogeneous enhancement, replicating the meningioma appearance, or as lesions with large necrotic regions and GBM-like heterogeneous contrast enhancement. [21] [22] Marked peritumoral edema is a characteristic and frequent hallmark of gliosarcomas observed on MRI. [19]
GBM and other cerebral gliomas rarely metastasize outside the brain. Numerous authors described incidences of metastatic foci that mixed gliomatous and sarcomatous components, [23] [24] while others reported metastatic foci that were entirely composed of the sarcomatous component. [25] [26] [27] Most gliosarcoma extracranial metastases are found in the lung and liver, but there have been reports of metastases elsewhere as well, [28] [29] [30] [31] [32] including evidence of intramedullary metastases to the cervical spine. [33]
Tumor removal, postoperative radiation treatment, and chemotherapy with nitrosureas, misonidazole, dacarbazine, temozolomide, doxorubicin , vincristine, cisplatin, mithramycin, ametophterin, thalidomide, or irinotecan have all been recorded as treatment options for gliosarcoma [34] and radiotherapy with temozolomide. [35]
PGS has a poor prognosis, [36] a prognosis of median survival of 4 months in untreated individuals. [37] The National Cancer Institute states that the relative five-year survival rate of gliosarcoma is only 5.6%. [2]
This article incorporates public domain material from Dictionary of Cancer Terms. U.S. National Cancer Institute.
Gliosarcoma | |
---|---|
Other names | Sarcomatous glioblastoma [1] |
Micrograph showing a gliosarcoma. Elastic van Gieson's stain. | |
Specialty | Neuro-oncology |
Usual onset | Between 40 and 60 years old [2] |
Prognosis | Five-year survival rate: 5.6% [2] |
Frequency | ~215 new diagnoses per year (United States) [2] |
Gliosarcoma is a rare type of glioma, a cancer of the brain that comes from glial, or supportive, brain cells, as opposed to the neural brain cells. Gliosarcoma is a malignant cancer, and is defined as a glioblastoma consisting of gliomatous and sarcomatous components. [3] Primary gliosarcoma (PGS) is classified as a grade IV tumor and a subtype of glioblastoma multiforme in the 2007 World Health Organization classification system (GBM). [4] Because of a lack of specific and clear diagnostic criteria, the word "gliosarcoma" was frequently used to refer to glial tumours with mesenchymal properties, [5] such as the ability to make collagen and reticulin. [6]
It is estimated that approximately 2.1% of all glioblastomas are gliosarcomas. Although most gliomas rarely show metastases outside the cerebrum, gliosarcomas have a propensity to do so, most commonly spreading through the blood to the lungs, and also liver and lymph nodes. [7]
They most commonly present in the temporal lobe [8] [9] and frontal lobe. [10]
Early reports claimed that the hyperplastic blood vessels that are frequently present in high grade gliomas underwent neoplastic change to become the sarcomatous components. [6] Feigin's early reports components of perivascular sarcomatous and hyperplastic arteries in gliosarcoma offered evidence for the "collision tumor" hypothesis. [11] Also, Studies demonstrating the sarcomatous component's histological sensitivity to markers of vascular endothelium such factor CD34, von Willebrand factor, and VIII supported this theory. [12] [13] [14] An alternative view that has recently gained support suggests that both gliosarcoma components have a monoclonal origin, with the sarcomatous component deriving from abnormal differentiation of malignant gliomal mesenchyma. First, gliomatous and sarcomatous components were shown to have similar p53 alterations by Biernat and colleagues. [15] In both tumor regions, Reis and colleagues found similar nuclear accumulation of p53, deletion of p16, mutations of PTEN,and amplifications of CDK4. [16] Other scientists then noted that both gliosarcoma components had similar genetic changes and chromosomal abnormalities of the kind often seen in GBM. [17] [18]
Gliosarcoma is rare; incidence ranges from 1.8 to 2.8 percent lower than that of GBMs. [19] PGS affects persons in their 6th to 7th years of life, and it is much more frequent in males than in females (with 1.4-1.8:1 ratio). [19] Depending on where the tumor is located, the reported presenting signs and symptoms, such as aphasia, headaches, hemiparesis, seizures, and cognitive loss, are similar with those of a fast developing intracranial tumor. Many researchers have come to the conclusion that these tumors are clinically identical to GBM due to their clinical similarities. [20]
On CT imaging, the lesions might show as Well-defined high-density lesion edges and homogeneous enhancement, replicating the meningioma appearance, or as lesions with large necrotic regions and GBM-like heterogeneous contrast enhancement. [21] [22] Marked peritumoral edema is a characteristic and frequent hallmark of gliosarcomas observed on MRI. [19]
GBM and other cerebral gliomas rarely metastasize outside the brain. Numerous authors described incidences of metastatic foci that mixed gliomatous and sarcomatous components, [23] [24] while others reported metastatic foci that were entirely composed of the sarcomatous component. [25] [26] [27] Most gliosarcoma extracranial metastases are found in the lung and liver, but there have been reports of metastases elsewhere as well, [28] [29] [30] [31] [32] including evidence of intramedullary metastases to the cervical spine. [33]
Tumor removal, postoperative radiation treatment, and chemotherapy with nitrosureas, misonidazole, dacarbazine, temozolomide, doxorubicin , vincristine, cisplatin, mithramycin, ametophterin, thalidomide, or irinotecan have all been recorded as treatment options for gliosarcoma [34] and radiotherapy with temozolomide. [35]
PGS has a poor prognosis, [36] a prognosis of median survival of 4 months in untreated individuals. [37] The National Cancer Institute states that the relative five-year survival rate of gliosarcoma is only 5.6%. [2]
This article incorporates public domain material from Dictionary of Cancer Terms. U.S. National Cancer Institute.