Astrocytoma

Astrocytoma is the most common glioma of the brain, it can also be located in the spinal cord. It has a number of histological forms with varying degrees of malignancy. They occur mainly supratentorial (adults), infratentorial localization predominates in children (astrocytomas represent about a third of infratentorial tumors in children). Astrocyte malignancies do not commonly metastasize, although this may occur  .

Spinal astrocytomas represent the most common intramedullary tumor in children, in adult patients they represent the second position in incidence (right after ependymomas). Furthermore, spinal astrocytomas are given a detailed description in an article dealing with spinal tumors.

Diagnosis
The degree of malignancy can be determined from CT and MRI, the use of contrast is important. It is often appropriate to use functional MRI, DTI - these imaging methods are essential primarily in cases where the tumor occurs in close proximity to eloquent areas.

Angiography is also used to image the vessels supplying the tumor. In both low-grade and high-grade astrocytomas, a pattern consistent with avascular mass, which tends to displace surrounding blood vessels, is typically seen. Strong vascularization can be observed angiographically, especially in glioblastomas.

In addition to the above, it can be used for more detailed diagnosis of PET, EEG or cerebrospinal fluid examinations to rule out other diagnoses (eg metastases , lymphomas , medulloblastomas, etc.).

WHO grade I
This group of astrocytic gliomas represents relatively non-aggressive and benign tumors. The collective name is the so-called pilocytic astrocytoma - it is a benign, slow-growing tumor. It is most often diagnosed in children and adolescents, it typically grows infratentorially (predominates in the cerebellum and brainstem ), but it can also occur in the lobar area. As the only astrocytoma, it does not behave expansively, it grows limited.

Pilocytic astrocytoma can quite often occur around the optic nerve - in the case of surgical resection, vision is not preserved postoperatively on the given side.

WHO grade II
Diffuse astrocytoma represents approximately 10-15% of all astrocytomas, is not aggressive, but may gradually develop into a more malignant form, and is therefore included in the WHO grade II group. It is typical for its infiltrative growth in the white matter, it occurs mainly in younger patients. The average time to onset of progression to higher degrees of astrocytomas is about 4-5 years (possible delay of proliferation can be achieved especially in younger patients by radical surgical resection).

WHO grade III
Anaplastic astrocytoma stands between diffuse astrocytoma and glioblastoma with regard to the prognosis of individual patients. It is a malignant tumor, compared to diffuse astrocytoma, anaplastic astrocytoma is more common (about 25% of all astrocytomas). It most often occurs in people between 40 and 50 years of age. Unlike glioblastomas, this tumor does not demonstrate signs of necrosis or vascular proliferation.

WHO grade IV
Glioblastoma is a WHO grade IV malignant tumor, most often diagnosed in adult patients, it represents approximately 50–60% of all astrocytomas (a total of 15% of primary brain neoplasms). Glioblastoma has a highly aggressive behavior, the prognosis is very unfavorable, it is still very resistant to treatment, it most often grows around the corticospinal tract, the expansion into the corpus callosum (so-called butterfly glioblastoma) is typical. Possible surgical resection is always followed by oncological treatment.

See the Glioblastoma multiforme page for more information .

Other classification
In addition to the WHO classification, astrocytomas can be divided into two groups: low-grade and high-grade.


 * 1) The low-grade pilocytic and diffuse astrocytoma, which is characterized by their non-aggressive biological nature, relatively good prognosis in the case of immediate treatment. They typically grow among preserved brain cells, are low in cell, with no mitoses.
 * 2) Anaplastic astrocytoma and glioblastoma are classified as high-grade astrocytomas - they are malignant, invasive, with cellular atypia and numerous mitoses, strongly vascularized, often contain cysts ( necrosis is typical especially for glioblastomas.

Low-grade astrocytomas prevalence in younger patients with increasing age are more common high-grade astrocytomas. This fact therefore supports the theory that the more low-grade (malignant) degenerate and pass into other forms, up to the secondary glioblastoma (only the pilocytic astrocytoma is a purely benign tumor).

Symptomatology
Individual symptomatology is directly dependent on the location of the tumor, its size, behavior and biological nature.

Intracranial astrocytomas
Supratentorially, astrocytomas are manifested by epileptic seizures ; if they occur in the eloquent area, patients may experience speech disorders, focal neurological deficits, and symptoms of intracranial hypertension (primarily vomiting, nausea, headache ).

Spinal astrocytomas
The most typical symptoms of spinal astrocytomas include motor ataxia, motor and sensory deficits, dysesthesia and associated sphincter disorders  .

Although astrocytomas usually occur solitarily, they may be accompanied by other spinal tumors, and in some patients type 2 neurofibromatosis (NH-2)  .

Therapy
In the benign form, radical resections are performed only in favorably stored ones (in non-eloquent areas - unnecessary for life). Sometimes radical graphic resection occurs. This is a resection where the tumor no longer appears on the MRI, but the tumor cells remain there (the entire lesion has not been removed). If resection is not possible, radiotherapy (RT) is possible.

In the malignant form, these tumors are usually indicated for surgery due to their large extent causing intracranial hypertension. We will remove as much of the tumor as possible, thus doing so-called internal decompression and supporting other modalities of oncological treatment ( RT, CHT ). Concomitant radiochemotherapy is often used.

In the case of tumor localization in the eloquent cerebral area, it may be indicated for awake surgery for perioperative mapping of individual brain functions.

Prognosis
The prognosis is quite unfavorable. Survival factors in low-grade cerebral astrocytoma:


 * age over 40,
 * the presence of neurological extinctions,
 * bearing size over 6 cm,
 * penetration into the contralateral hemisphere,
 * diffusion form.

The risk of progression to glioblastoma is high in the presence of three or more of these factors.

The probability of recurrence in spinal astrocytomas is approximately 42–48% after 10 years, depending on the biological nature of the tumor, complete / partial resection  . The risk of recurrence in completely resected spinal astrocytomas is around 6.3%, while in the case of partial resections, this value is about 42.5% within 10 years after surgery  .

In adult patients, the prognosis is better compared to children.

related articles

 * Brain gliomas
 * Spinal tumors
 * CNS tumors
 * Oligodendroglioma
 * Ependymoma

Reference

 * 1) KEPES, JJ, CM STRIEBINGER and CE BRACKETT. Gliomas (astrocytomas) of the brain-stem with spinal intra- and extradural metastases: report of three cases ..  Journal of Neurology, Neurosurgery & Psychiatry. 1976, vol. 1, vol 39, pp. 66-76, ISSN 0022-3050. DOI: 10.1136 / jnnp.39.1.66.
 * 2) ↑ BARKOVICH, A ..  Diagnostic Imaging: Brain. - edition. Amirsys, 2016. 1197 pp.  ISBN 9780323377546.
 * 3) ↑ BRANT, William and Clyde HELMS. Fundamentals of Diagnostic Radiology. - edition. Lippincott Williams & Wilkins, 2007. 1559 pp.  ISBN 9780781761352.
 * 4) ↑ DIRVEN, CMF, JJA MOOIJ and WM MOLENAAR. Cerebellar pilocytic astrocytoma: a treatment protocol based upon analysis of 73 cases and a review of the literature. Child's Nervous System. 1997, vol. 1, vol 13, pp. 17-23, ISSN 0256-7040. DOI: 10.1007 / s003810050033.
 * 5) ↑ BELL, D, BP CHITNAVIS and S AL-SARRAJ. Pilocytic astrocytoma of the adult - clinical features, radiological features and management. British Journal of Neurosurgery. 2004, vol. 6, vol. 18, pp. 613-616, ISSN 0268-8697. DOI: 10.1080 / 02688690400022896.
 * 6) ↑ JOHNSON, Derek R., Paul D. BROWN and Evanthia GALANIS. Pilocytic astrocytoma survival in adults: analysis of the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute. Journal of Neuro-Oncology. 2012, vol. 1, vol 108, pp. 187-193, ISSN 0167-594X. DOI: 10.1007 / s11060-012-0829-0.
 * 7) ↑ AJLAN, Abdulrazag and Lawrence RECHT. Supratentorial Low-Grade Diffuse Astrocytoma: Medical Management. Seminars in Oncology. 2014, vol. 4, vol 41, pp. 446-457, ISSN 0093-7754. DOI: 10.1053 / j.seminoncol.2014.06.013.
 * 8) ↑ CACCESE, Mario, Marta PADOVAN and Domenico D'AVELLA. Anaplastic Astrocytoma: State of the art and future directions. Critical Reviews in Oncology / Hematology. 2020, vol. ?, vol 153, pp. 103062, ISSN 1040-8428. DOI: 10.1016 / j.critrevonc.2020.103062.
 * 9) ↑ GRIMM, Sean A and Marc C CHAMBERLAIN. Anaplastic astrocytoma. CNS Oncology. 2016, year. 3, vol. 5, pp. 145-157, ISSN 2045-0907. DOI: 10.2217 / cns-2016-0002.
 * 10) ↑ DAYANI, Fara, Jacob S. YOUNG and Alexander BONTE. Safety and outcomes of resection of butterfly glioblastoma. Neurosurgical Focus. 2018, year. 6, vol 44, pp. E4, ISSN 1092-0684. DOI: 10.3171 / 2018.3.focus1857.
 * 11) ↑ OHGAKI, Hiroko and Paul KLEIHUES. The Definition of Primary and Secondary Glioblastoma. Clinical Cancer Research. 2012, vol. 4, vol. 19, pp. 764-772, ISSN 1078-0432. DOI: 10.1158 / 1078-0432.ccr-12-3002.
 * 12) ↑ SATTAR, Husain. Fundamentals of Pathology: Medical Course and Step 1 Review. - edition. Pathoma.com, 2017. 223 pp.  ISBN 9780983224631.
 * 13) ↑ BURGER, Peter C .. Pathology of Brain Stem Astrocytomas. Pediatric Neurosurgery. 1996, vol. 1, vol 24, pp. 35-40, ISSN 1423-0305. DOI: 10.1159 / 000121012.
 * 14) ↑ NAZZARO, Jules M. and Edward A. NEUWELT. The role of surgery in the management of supratentorial intermediate and high-grade astrocytomas in adults. Journal of Neurosurgery. 1990, vol. 3, vol 73, pp. 331-344, ISSN 0022-3085. DOI: 10.3171 / jns.1990.73.3.0331.
 * 15) ↑Jump up to:a b ARNAUTOVIĆ, Kenan and Ziya GOKASLAN. Spinal Cord Tumors. - edition. Springer, 2019. 540 pp.  ISBN 9783319994383.
 * 16) ↑ BABU, Ranjith, Isaac O. KARIKARI and Timothy R. OWENS. Spinal Cord Astrocytomas. Spine. 2014, vol. 7, vol. 39, pp. 533-540, ISSN 0362-2436. DOI: 10.1097 / brs.0000000000000190.
 * 17) ↑ ROBINSON, Clifford G., Richard A. PRAYSON and Joseph F. HAHN. Long-term survival and functional status of patients with low-grade astrocytoma of spinal cord. International Journal of Radiation Oncology * Biology * Physics. 2005, vol. 1, vol 63, pp. 91-100, ISSN 0360-3016. DOI: 10.1016 / j.ijrobp.2005.01.009.
 * 18) ↑Jump up to:a b KLEKAMP, Jörg and Madjid SAMII. Surgery of Spinal Tumors. - edition. Springer Science & Business Media, 2007. 526 pp.  ISBN 9783540447153.
 * 19) ↑ KLEKAMP, Jörg. Treatment of intramedullary tumors: analysis of surgical morbidity and long-term results. Journal of Neurosurgery: Spine. 2013, vol. 1, vol 19, pp. 12-26, ISSN 1547-5654. DOI: 10.3171 / 2013.3.spine121063.
 * 20) ↑ KARIKARI, Isaac O., Shahid M. NIMJEE and Tiffany R. HODGES. Impact of Tumor Histology on Resectability and Neurological Outcome in Primary Intramedullary Spinal Cord Tumors. Neurosurgery. 2015, vol. suppl_1, vol 76, pp. S4-S13, ISSN 0148-396X. DOI: 10.1227 / 01.neu.0000462073.71915.12.
 * 21) ↑ BENEŠ, Vladimír, Pavel BARSA and Vladimír BENEŠ. Prognostic factors in intramedullary astrocytomas: a literature review. European Spine Journal. 2009, vol. 10, vol. 18, pp. 1397-1422, ISSN 0940-6719. DOI: 10.1007 / s00586-009-1076-8.
 * 22) ↑ RACO, Antonino, Vincenzo ESPOSITO and Jacopo LENZI, et al. Long-term follow-up of intramedullary spinal cord tumors: a series of 202 cases. Neurosurgery [online] . 2005, vol 56, no. 5, pp. 972-81; discussion 972-81, also available from < https://www.ncbi.nlm.nih.gov/pubmed/15854245 >. ISSN 0148-396X (print), 1524-4040.