Desmoplastic Astrocytoma

Background

This rare brain tumor desmoplastic cerebral astrocytoma of infancy (DCAI) is a rare tumor that presents as a large hemispheric mass in infants. Despite a worrisome histologic picture that may be confused with a sarcoma, the tumor has an overall good prognosis.

OUTLINE

Epidemiology

Disease Associations

Pathogenesis

Laboratory/Radiologic/
Other Diagnostic Testing

Gross Appearance and Clinical Variants

Histopathological Features and Variants

Special Stains/
Immunohistochemistry/
Electron Microscopy

Differential Diagnosis

Prognosis

Treatment

Commonly Used Terms

Internet Links

EPIDEMIOLOGY CHARACTERIZATION

SYNONYMS Desmoplastic cerebral astrocytoma of infancy (DCAI)
Desmoplastic infantile astrocytoma
Superficial cerebral astrocytoma attached to dura

INCIDENCE Rare

AGE RANGE-MEDIAN Infancy

PATHOGENESIS CHARACTERIZATION

CHROMOSOMAL ABNORMALITIES

Desmoplastic infantile astrocytoma and ganglioglioma: a search for genomic characteristics.

Kros JM, Delwel EJ, de Jong TH, Tanghe HL, van Run PR, Vissers K, Alers JC.

Department of Pathology, University Hospital Rotterdam-Dijkzigt, P.O. Box 2040, 3000 CA Rotterdam, The Netherlands.
Acta Neuropathol (Berl) 2002 Aug;104(2):144-8 Abstract quote
In the present study the clinical data, histology, proliferation rate, DNA ploidy status and the results of TP53 mutation analysis and comparative genomic hybridization (CGH) of three typical cases of desmoplastic infantile astrocytoma and ganglioglioma are presented.

Postoperative disease-free intervals of 11, 8 and 3 years were recorded and in none of the cases were radiological signs of tumor recurrence.

No TP53 mutations (exons 5-8) were found. CGH analysis revealed loss of 8p22-pter in one case, while in another case gain of 13q21 was detected. In the case with the follow-up of 11 years an aneuploid DNA-flow cytogram along with slightly increased MIB-1 labeling index (LI) was found.

The results demonstrate little genetic instability in these low-grade lesions. DNA-aneuploidy seems not to be indicative of tumor progression.

It is concluded that the genetic aberrations found in desmoplastic infantile ganglioglioma differ from those encountered in common astrocytomas.

RADIOLOGY/
LABORATORY

MRI

MR imaging in the diagnosis of desmoplastic infantile tumor: retrospective study of six cases.

Trehan G, Bruge H, Vinchon M, Khalil C, Ruchoux MM, Dhellemmes P, Ares GS.

Department of Neuroradiology, Hopital Roger Salengro, Centre Hospitalier Regional Universitaire de Lille, Lille, France.

AJNR Am J Neuroradiol. 2004 Jun-Jul;25(6):1028-33. Abstract quote

BACKGROUND AND PURPOSE: Desmoplastic infantile tumors (DITs) are rare supratentorial tumors of infancy with a favorable prognosis. Radiologic and histologic features of DIT are misleading, and DIT may be misinterpreted as a malignant lesion. We have studied the usefulness of MR imaging in the diagnosis of these tumors.

METHODS: Between 1995 and 2002, six DITs were diagnosed in young children at our institution. Neuroimaging, age at diagnosis, sex, clinical presentation, symptoms duration, follow-up, and development were studied retrospectively. Contrast-enhanced CT and MR images were available. MR study included T1-, T2-, and postgadolinium T1-weighted sequences in the axial, sagittal, and coronal planes.

RESULTS: These tumors were massive and predominantly cystic, with preferential frontal and parietal involvement. Typically, a DIT appears as a hypointense cystic mass with an isointense peripheral solid component on T1-weighted MR images. The peripheral solid component enhances after gadolinium administration. On T2-weighted MR images, the cystic component is hyperintense and the solid portion isointense or heterogeneous. The cystic portion is usually located deep inside the lesion, whereas its solid portion is peripheral. Meningeal enhancement and thickening adjacent to the solid portion of the tumor, calcifications, bone abnormalities adjacent to the tumor consisting of thinning and deformation were noted in 50% of our cases. Edema was usually absent or moderate. Median follow-up was 32 months, and no recurrence was noted except for one atypical case with incomplete excision, which led to the patient's death.

CONCLUSION: Despite their malignant appearance, MR imaging features of DIT may help in the diagnosis and obviate unnecessary chemotherapy or radiation therapy.

GROSS APPEARANCE/
CLINICAL VARIANTS CHARACTERIZATION

GENERAL

VARIANTS

MULTIFOCAL

Multifocal desmoplastic astrocytoma, frontal lobe dysplasia, and simian crease.

Bock D, Rummele P, Friedrich M, Wolff JE.

Pediatric Oncology, Department of Pediatrics, Klinik St Hedwig, Regensburg, Germany.
J Pediatr 2002 Sep;141(3):445

HISTOLOGICAL TYPES CHARACTERIZATION

GENERAL

Desmoplastic cerebral astrocytoma of infancy. Light microscopy, immunocytochemistry, and ultrastructure.

de Chadarevian JP, Pattisapu JV, Faerber EN.

Department of Pediatric Anatomical Pathology, St. Christopher's Hospital for Children, Philadelphia, PA 19133
Cancer 1990 Jul 1;66(1):173-9 Abstract quote
The first detailed ultrastructural study of a superficial desmoplastic cerebral astrocytoma of infancy is reported.

This is a neoplasm which mimics a mesenchymal tumor, originally described in 1984 under the name of "superficial cerebral astrocytoma attached to dura." This tumor, which is believed to have a good prognosis, was resected from the frontoparietal region of a 6.5-month-old girl, in whom it had presented as a large densely enhancing vascular and cystic mass. The ultrastructure of the tumor appeared to be distinctive, characterized by the absence of neuronal elements, and the presence of large amounts of redundant and sometimes extensively duplicated basal laminal material and collagen between nonpleomorphic and nonlipidized astrocytes, corresponding to the reticulin fibers seen by light microscopic analysis between the S-100 protein and glial fibrillary acidic protein (GFAP)-positive cells.

The features of the tumor, its differential diagnosis, and its relationship to other pediatric supratentorial tumors are discussed.

Desmoplastic cerebral astrocytomas of infancy: a histopathologic, immunohistochemical, ultrastructural, and molecular genetic study.

Louis DN, von Deimling A, Dickersin GR, Dooling EC, Seizinger BR.

Department of Pathology, Massachusetts General Hospital, Boston 02114.
Hum Pathol 1992 Dec;23(12):1402-9 Abstract quote
The desmoplastic cerebral astrocytoma of infancy (DCAI) is a rare tumor that presents as a large hemispheric mass in infants. Despite an ominous histologic picture that may resemble a sarcoma, the tumor is astrocytic and has a good prognosis.

We present two cases of DCAI, with histopathologic, immunohistochemical, ultrastructural, and molecular genetic data, and draw the following conclusions: (1) the diagnosis of DCAI requires a high index of suspicion and immunohistochemical or ultrastructural proof of astrocytic differentiation; (2) the data argue against nosologically equating these tumors with the desmoplastic infantile ganglioglioma, pleomorphic xanthoastrocytoma, or gliofibroma; (3) the components of the extensive tumor basal lamina may be elaborated by the tumor cells themselves and may contribute in an autocrine fashion to the slow growth of these lesions; and (4) if the lack of allelic loss on chromosomes 17p (including the p53 tumor suppressor gene locus) and 10 seen in our cases is found in other cases of DCAI, this may further distinguish the DCAI from other astrocytomas.

VARIANTS

ATYPICAL GLIAL CELLS

Desmoplastic cerebral astrocytoma of infancy intermingling with atypical glial cells.

Kurose A, Beppu T, Miura Y, Suzuki M, Ogawa A, Arai H, Kubo Y, Sugawara A, Sawai T.

Department of Pathology, Iwate Medical University, Morioka, Japan.
Pathol Int 2000 Sep;50(9):744-9 Abstract quote
Despite the rarity of desmoplastic cerebral astrocytoma of infancy (DCAI), it has distinct clinical and pathological features.

The present case is a typical DCAI except for its detection and operational age and intermingling with pleomorphic glial cells. In this case, although a cystic lesion of the right temporal lobe was noticed when the patient was 6 months old, it was not regarded as a tumor and wasn't removed until he was 9 years old. It is quite unusual that a DCAI was able to exist in the cerebrum for 9 years. However, no metastasis occurred and distinct macroscopic and microscopic features of the tumor were not different from typical DCAI except for an intermingling with pleomorphic glial cells. Furthermore, even in the pleomorphic areas, the absence of necrosis and an MIB-1 index of 2.9% indicated non-aggressive growth.

These features of the present case may provide additional information as to the character of DCAI, which generally has a favorable prognosis.

GLIOFIBROMA

Gliofibroma: a distinct entity or a subtype of desmoplastic astrocytoma?

Prayson RA.

Department of Anatomic Pathology, Cleveland Clinic Foundation, OH 44195, USA.
Hum Pathol 1996 Jun;27(6):610-3 Abstract quote
Gliofibromas are rarely encountered astrocytic neoplasms characterized by an admixture of astrocytic and fibroblastic cell components. The exact nature of these rare tumors are still a matter of considerable debate.

This article reports a case of gliofibroma occurring in a 3-month-old boy. The astrocytic component of the tumor stained diffusely positive for glial fibrillary acidic protein (GFAP) and S-100 protein.

Prominent reticulin staining was observed within the fibroblastic component of the tumor. The MIB1 labeling index (positive number of tumor cells divided by total tumor cells counted X 100) was low (0.9), supporting the general slow growth of these tumors. Immunohistochemical staining with antibody against p53 protein was negative.

Gliofibromas seem to be a low-grade variant of an astrocytoma that shares many features with other desmoplastic astrocytic neoplasms (desmoplastic infantile astrocytoma, desmoplastic infantile ganglioglioma) including a generally favorable prognosis.

SPECIAL STAINS/
IMMUNOPEROXIDASE/
OTHER CHARACTERIZATION

SPECIAL STAINS

IMMUNOPEROXIDASE

Desmoplastic cerebral astrocytoma of infancy. A case report with immunohistochemical, ultrastructural and proliferation studies.

Aydin F, Ghatak NR, Salvant J, Muizelaar P.

Tulane University Medical School, Department of Pathology, New Orleans, LA 70112.
Acta Neuropathol (Berl) 1993;86(6):666-70 Abstract quote
We present a case of desmoplastic cerebral astrocytoma of infancy (DCAI) in a 7 1/2-month-old girl and include immunohistochemical, ultrastructural and proliferative activity studies.

The dural-based cystic tumor showed a biphasic pattern consisting of glial fibrillary acidic protein (GFAP)-positive astrocytes embedded in a desmoplastic stroma. The astrocytic processes were lined with basal lamina at their surface contacting the collagen. Scattered islands of undifferentiated small cells were seen acquiring GFAP positivity at their peripheral zone facing the collagen.

Studies with silver nucleolar organizer region and proliferating cell nuclear antigen disclosed a high proliferative activity. Flow cytometric study showed an elevated S phase and 15% hypertetraploid cell population.

These findings contrast the favorable prognosis of the tumor at 26 months follow-up. Probably, extracellular-matrix-induced maturation of the undifferentiated cells with the formation of basal lamina may account for this unique disparity.

DIFFERENTIAL DIAGNOSIS KEY DIFFERENTIATING FEATURES

ASTROBLASTOMA

Astroblastomas: a pathological study of 23 tumors, with a postoperative follow-up in 13 patients.

Bonnin JM, Rubinstein LJ.

Department of Pathology, University of Virginia School of Medicine, Charlottesville.

Neurosurgery 1989 Jul;25(1):6-13 Abstract quote
Astroblastomas are rare, usually circumscribed, supratentorial tumors of young subjects and are characterized by a perivascular arrangement of the tumor cells. Their clinical behavior is unpredictable and their prognosis has been regarded as intermediate between that of astrocytomas and glioblastomas.

A personal series of 23 astroblastomas was reviewed, adequate postoperative follow-up being available in 13 patients. Two distinct histological types were encountered: low-grade and high-grade. The low-grade type comprised tumors with better differentiated and more benign-appearing microscopical features.

Five of the 8 patients with tumors of this type who were available for follow-up have survived from 3 to 20 years after treatment; in 1 patient the tumor converted into a fatal glioblastoma after 4 1/2 years. The high-grade type consisted of tumors with more anaplastic features. Three of the 4 patients with tumors of this type available for follow-up died after 1 1/2 to 2 1/2 years, the astroblastomas in 2 of them having converted into a glioblastoma and a gliosarcoma, respectively. One patient, however, has had an unexpected length of postoperative survival of 11 1/2 years.

The best clinical results were obtained after total or subtotal resection of the tumor, followed by radiotherapy. The role of chemotherapy is still uncertain. This form of glioma illustrates the discrepancies that may sometimes be apparent between histopathological features and length of postoperative survival. The prognosis is also further complicated by the potential of the astroblastoma to convert into a more malignant type of glioma.

XANTHO-ASTROCYTOMA, PLEOMORPHIC

Pleomorphic xanthoastrocytoma with desmoplastic reaction: angiomatous variant. Report of two cases.

Sugita Y, Kepes JJ, Shigemori M, Kuramoto S, Reifenberger G, Kiwit JC, Wechsler W.

Department of Pathology and Oncology, University of Kansas College of Health Sciences and Hospital, Kansas City 66103.
Clin Neuropathol 1990 Nov-Dec;9(6):271-8 Abstract quote
Two cases of cerebral pleomorphic xanthoastrocytomas (PXA-s) with prominent vascularity and desmoplastic changes occurring in young subjects are presented. The tumors displayed the marked pleomorphism characteristic of PXA-s and had variable cellularity. The cytoplasm of many tumor cells contained an abundance of lipid droplets. Most tumor cells were positive for glial fibrillary acidic protein. The unusual feature about these tumors was the presence of very large numbers of tiny blood vessels with variable thickness of their walls.

In many areas the small vessels and the neoplastic astrocytes were in close proximity to each other, with capillaries adjacent to or protruding into tumor cell cytoplasm, reminiscent of the pattern seen in highly vascularized or "angiomatous" meningiomas. In other areas extensive fibrosis was seen.

We feel that the latter, as in the cases of comparably vascular meningiomas, had its origin in congelation and secondary organization of plasma proteins that have exuded through leaky walls of newly formed blood vessels. These are the first reported cases of PXA with an angiogliomatous pattern.

PROGNOSIS AND TREATMENT CHARACTERIZATION

PROGNOSTIC FACTORS

METASTASES

Desmoplastic infantile astrocytoma with metastases at presentation.

Setty SN, Miller DC, Camras L, Charbel F, Schmidt ML.

Department of Pediatrics, University of Illinois College of Medicine, Chicago 60612, USA

Mod Pathol 1997 Sep;10(9):945-51 Abstract quote
A 4-month-old child presented with nystagmus and macrocephaly. He had a large tumor in the suprasellar and hypothalamic region, as well as two smaller similar masses in the posterior fossa and one in the spinal canal.

A biopsy of the suprasellar mass revealed it to be a desmoplastic infantile cerebral astrocytoma. Cerebrospinal fluid obtained at surgery before tumor manipulation showed clusters of malignant cells immunopositive for glial fibrillary acidic protein. In our opinion, the smaller tumors were metastases from the large suprasellar primary astrocytoma.

Review of all of the previously reported cases of desmoplastic infantile cerebral astrocytoma and of the related neoplastic entity desmoplastic infantile ganglioglioma suggested that this was a unique case, but we still recommend caution with respect to the previously accepted notion that desmoplastic infantile neuroepithelial tumors are virtually benign neoplasms.

TREATMENT

Henry JB. Clinical Diagnosis and Management by Laboratory Methods. Twentieth Edition. WB Saunders. 2001.
Rosai J. Ackerman's Surgical Pathology. Ninth Edition. Mosby 2004.
Sternberg S. Diagnostic Surgical Pathology. Fourth Edition. Lipincott Williams and Wilkins 2004.
Robbins Pathologic Basis of Disease. Seventh Edition. WB Saunders 2005.
DeMay RM. The Art and Science of Cytopathology. Volume 1 and 2. ASCP Press. 1996.
Weedon D. Weedon's Skin Pathology Second Edition. Churchill Livingstone. 2002
Fitzpatrick's Dermatology in General Medicine. 5th Edition. McGraw-Hill. 1999.
Weiss SW and Goldblum JR. Enzinger and Weiss's Soft Tissue Tumors. Fourth Edition. Mosby 2001.

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Last Updated June 9, 2005

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HISTOLOGICAL TYPES	CHARACTERIZATION
GENERAL
Desmoplastic cerebral astrocytoma of infancy. Light microscopy, immunocytochemistry, and ultrastructure. de Chadarevian JP, Pattisapu JV, Faerber EN. Department of Pediatric Anatomical Pathology, St. Christopher's Hospital for Children, Philadelphia, PA 19133	Cancer 1990 Jul 1;66(1):173-9 Abstract quote The first detailed ultrastructural study of a superficial desmoplastic cerebral astrocytoma of infancy is reported. This is a neoplasm which mimics a mesenchymal tumor, originally described in 1984 under the name of "superficial cerebral astrocytoma attached to dura." This tumor, which is believed to have a good prognosis, was resected from the frontoparietal region of a 6.5-month-old girl, in whom it had presented as a large densely enhancing vascular and cystic mass. The ultrastructure of the tumor appeared to be distinctive, characterized by the absence of neuronal elements, and the presence of large amounts of redundant and sometimes extensively duplicated basal laminal material and collagen between nonpleomorphic and nonlipidized astrocytes, corresponding to the reticulin fibers seen by light microscopic analysis between the S-100 protein and glial fibrillary acidic protein (GFAP)-positive cells. The features of the tumor, its differential diagnosis, and its relationship to other pediatric supratentorial tumors are discussed.
Desmoplastic cerebral astrocytomas of infancy: a histopathologic, immunohistochemical, ultrastructural, and molecular genetic study. Louis DN, von Deimling A, Dickersin GR, Dooling EC, Seizinger BR. Department of Pathology, Massachusetts General Hospital, Boston 02114.	Hum Pathol 1992 Dec;23(12):1402-9 Abstract quote The desmoplastic cerebral astrocytoma of infancy (DCAI) is a rare tumor that presents as a large hemispheric mass in infants. Despite an ominous histologic picture that may resemble a sarcoma, the tumor is astrocytic and has a good prognosis. We present two cases of DCAI, with histopathologic, immunohistochemical, ultrastructural, and molecular genetic data, and draw the following conclusions: (1) the diagnosis of DCAI requires a high index of suspicion and immunohistochemical or ultrastructural proof of astrocytic differentiation; (2) the data argue against nosologically equating these tumors with the desmoplastic infantile ganglioglioma, pleomorphic xanthoastrocytoma, or gliofibroma; (3) the components of the extensive tumor basal lamina may be elaborated by the tumor cells themselves and may contribute in an autocrine fashion to the slow growth of these lesions; and (4) if the lack of allelic loss on chromosomes 17p (including the p53 tumor suppressor gene locus) and 10 seen in our cases is found in other cases of DCAI, this may further distinguish the DCAI from other astrocytomas.
VARIANTS
ATYPICAL GLIAL CELLS
Desmoplastic cerebral astrocytoma of infancy intermingling with atypical glial cells. Kurose A, Beppu T, Miura Y, Suzuki M, Ogawa A, Arai H, Kubo Y, Sugawara A, Sawai T. Department of Pathology, Iwate Medical University, Morioka, Japan.	Pathol Int 2000 Sep;50(9):744-9 Abstract quote Despite the rarity of desmoplastic cerebral astrocytoma of infancy (DCAI), it has distinct clinical and pathological features. The present case is a typical DCAI except for its detection and operational age and intermingling with pleomorphic glial cells. In this case, although a cystic lesion of the right temporal lobe was noticed when the patient was 6 months old, it was not regarded as a tumor and wasn't removed until he was 9 years old. It is quite unusual that a DCAI was able to exist in the cerebrum for 9 years. However, no metastasis occurred and distinct macroscopic and microscopic features of the tumor were not different from typical DCAI except for an intermingling with pleomorphic glial cells. Furthermore, even in the pleomorphic areas, the absence of necrosis and an MIB-1 index of 2.9% indicated non-aggressive growth. These features of the present case may provide additional information as to the character of DCAI, which generally has a favorable prognosis.
GLIOFIBROMA
Gliofibroma: a distinct entity or a subtype of desmoplastic astrocytoma? Prayson RA. Department of Anatomic Pathology, Cleveland Clinic Foundation, OH 44195, USA.	Hum Pathol 1996 Jun;27(6):610-3 Abstract quote Gliofibromas are rarely encountered astrocytic neoplasms characterized by an admixture of astrocytic and fibroblastic cell components. The exact nature of these rare tumors are still a matter of considerable debate. This article reports a case of gliofibroma occurring in a 3-month-old boy. The astrocytic component of the tumor stained diffusely positive for glial fibrillary acidic protein (GFAP) and S-100 protein. Prominent reticulin staining was observed within the fibroblastic component of the tumor. The MIB1 labeling index (positive number of tumor cells divided by total tumor cells counted X 100) was low (0.9), supporting the general slow growth of these tumors. Immunohistochemical staining with antibody against p53 protein was negative. Gliofibromas seem to be a low-grade variant of an astrocytoma that shares many features with other desmoplastic astrocytic neoplasms (desmoplastic infantile astrocytoma, desmoplastic infantile ganglioglioma) including a generally favorable prognosis.

Epidemiology
Disease Associations
Pathogenesis
Laboratory/Radiologic/ Other Diagnostic Testing
Gross Appearance and Clinical Variants
Histopathological Features and Variants
Special Stains/ Immunohistochemistry/ Electron Microscopy
Differential Diagnosis
Prognosis
Treatment
Commonly Used Terms
Internet Links

EPIDEMIOLOGY	CHARACTERIZATION
SYNONYMS	Desmoplastic cerebral astrocytoma of infancy (DCAI) Desmoplastic infantile astrocytoma Superficial cerebral astrocytoma attached to dura
INCIDENCE	Rare
AGE RANGE-MEDIAN	Infancy

GROSS APPEARANCE/ CLINICAL VARIANTS	CHARACTERIZATION
GENERAL
VARIANTS
MULTIFOCAL
Multifocal desmoplastic astrocytoma, frontal lobe dysplasia, and simian crease. Bock D, Rummele P, Friedrich M, Wolff JE. Pediatric Oncology, Department of Pediatrics, Klinik St Hedwig, Regensburg, Germany.	J Pediatr 2002 Sep;141(3):445

SPECIAL STAINS/ IMMUNOPEROXIDASE/ OTHER	CHARACTERIZATION
SPECIAL STAINS
IMMUNOPEROXIDASE
Desmoplastic cerebral astrocytoma of infancy. A case report with immunohistochemical, ultrastructural and proliferation studies. Aydin F, Ghatak NR, Salvant J, Muizelaar P. Tulane University Medical School, Department of Pathology, New Orleans, LA 70112.	Acta Neuropathol (Berl) 1993;86(6):666-70 Abstract quote We present a case of desmoplastic cerebral astrocytoma of infancy (DCAI) in a 7 1/2-month-old girl and include immunohistochemical, ultrastructural and proliferative activity studies. The dural-based cystic tumor showed a biphasic pattern consisting of glial fibrillary acidic protein (GFAP)-positive astrocytes embedded in a desmoplastic stroma. The astrocytic processes were lined with basal lamina at their surface contacting the collagen. Scattered islands of undifferentiated small cells were seen acquiring GFAP positivity at their peripheral zone facing the collagen. Studies with silver nucleolar organizer region and proliferating cell nuclear antigen disclosed a high proliferative activity. Flow cytometric study showed an elevated S phase and 15% hypertetraploid cell population. These findings contrast the favorable prognosis of the tumor at 26 months follow-up. Probably, extracellular-matrix-induced maturation of the undifferentiated cells with the formation of basal lamina may account for this unique disparity.

DIFFERENTIAL DIAGNOSIS	KEY DIFFERENTIATING FEATURES
ASTROBLASTOMA
Astroblastomas: a pathological study of 23 tumors, with a postoperative follow-up in 13 patients. Bonnin JM, Rubinstein LJ. Department of Pathology, University of Virginia School of Medicine, Charlottesville.	Neurosurgery 1989 Jul;25(1):6-13 Abstract quote Astroblastomas are rare, usually circumscribed, supratentorial tumors of young subjects and are characterized by a perivascular arrangement of the tumor cells. Their clinical behavior is unpredictable and their prognosis has been regarded as intermediate between that of astrocytomas and glioblastomas. A personal series of 23 astroblastomas was reviewed, adequate postoperative follow-up being available in 13 patients. Two distinct histological types were encountered: low-grade and high-grade. The low-grade type comprised tumors with better differentiated and more benign-appearing microscopical features. Five of the 8 patients with tumors of this type who were available for follow-up have survived from 3 to 20 years after treatment; in 1 patient the tumor converted into a fatal glioblastoma after 4 1/2 years. The high-grade type consisted of tumors with more anaplastic features. Three of the 4 patients with tumors of this type available for follow-up died after 1 1/2 to 2 1/2 years, the astroblastomas in 2 of them having converted into a glioblastoma and a gliosarcoma, respectively. One patient, however, has had an unexpected length of postoperative survival of 11 1/2 years. The best clinical results were obtained after total or subtotal resection of the tumor, followed by radiotherapy. The role of chemotherapy is still uncertain. This form of glioma illustrates the discrepancies that may sometimes be apparent between histopathological features and length of postoperative survival. The prognosis is also further complicated by the potential of the astroblastoma to convert into a more malignant type of glioma.
XANTHO-ASTROCYTOMA, PLEOMORPHIC
Pleomorphic xanthoastrocytoma with desmoplastic reaction: angiomatous variant. Report of two cases. Sugita Y, Kepes JJ, Shigemori M, Kuramoto S, Reifenberger G, Kiwit JC, Wechsler W. Department of Pathology and Oncology, University of Kansas College of Health Sciences and Hospital, Kansas City 66103.	Clin Neuropathol 1990 Nov-Dec;9(6):271-8 Abstract quote Two cases of cerebral pleomorphic xanthoastrocytomas (PXA-s) with prominent vascularity and desmoplastic changes occurring in young subjects are presented. The tumors displayed the marked pleomorphism characteristic of PXA-s and had variable cellularity. The cytoplasm of many tumor cells contained an abundance of lipid droplets. Most tumor cells were positive for glial fibrillary acidic protein. The unusual feature about these tumors was the presence of very large numbers of tiny blood vessels with variable thickness of their walls. In many areas the small vessels and the neoplastic astrocytes were in close proximity to each other, with capillaries adjacent to or protruding into tumor cell cytoplasm, reminiscent of the pattern seen in highly vascularized or "angiomatous" meningiomas. In other areas extensive fibrosis was seen. We feel that the latter, as in the cases of comparably vascular meningiomas, had its origin in congelation and secondary organization of plasma proteins that have exuded through leaky walls of newly formed blood vessels. These are the first reported cases of PXA with an angiogliomatous pattern.

PROGNOSIS AND TREATMENT	CHARACTERIZATION
PROGNOSTIC FACTORS
METASTASES
Desmoplastic infantile astrocytoma with metastases at presentation. Setty SN, Miller DC, Camras L, Charbel F, Schmidt ML. Department of Pediatrics, University of Illinois College of Medicine, Chicago 60612, USA	Mod Pathol 1997 Sep;10(9):945-51 Abstract quote A 4-month-old child presented with nystagmus and macrocephaly. He had a large tumor in the suprasellar and hypothalamic region, as well as two smaller similar masses in the posterior fossa and one in the spinal canal. A biopsy of the suprasellar mass revealed it to be a desmoplastic infantile cerebral astrocytoma. Cerebrospinal fluid obtained at surgery before tumor manipulation showed clusters of malignant cells immunopositive for glial fibrillary acidic protein. In our opinion, the smaller tumors were metastases from the large suprasellar primary astrocytoma. Review of all of the previously reported cases of desmoplastic infantile cerebral astrocytoma and of the related neoplastic entity desmoplastic infantile ganglioglioma suggested that this was a unique case, but we still recommend caution with respect to the previously accepted notion that desmoplastic infantile neuroepithelial tumors are virtually benign neoplasms.
TREATMENT