Gamma knife radiosurgery for central neurocytoma

Abstract

BACKGROUND.Little is known about long‐term results of gamma knife (GK) stereotactic radiosurgery (SRS) as a primary or a secondary postoperative therapy for central neurocytomas (CNs). The authors retrospectively reviewed long‐term outcomes of 13 patients with CN treated with GK SRS.METHODS.Thirteen patients were treated with GK SRS as a primary (6 patients) or a secondary postoperative therapy (7 patients). Follow‐up clinical status and brain magnetic resonance imaging (MRI) were thoroughly analyzed. The functional status of patients was assessed with the Karnofsky Performance Scale during follow‐up.RESULTS.The median follow‐up period for clinical status and imaging studies was 61 months (range, 6 months to 96 months). Tumors decreased in 5 patients who received GK SRS as a primary treatment. However, the tumor recurred in 2 patients treated with a secondary GK SRS after surgery from the residual tumor bed that was not covered by the GK SRS. Parenchymal changes and secondary malignancies were not found in follow‐up MRIs of all 13 patients. The Karnofsky Performance Scale score of all patients, except for 1 patient who suffered from an unrelated anteriorly communicating arterial aneurysmal rupture, did not change after GK SRS.CONCLUSIONS.GK SRS may be useful as a primary or a secondary postoperative therapy for the treatment of CN. However, more attention should be paid to residual or recurrent CN during treatment, and regular long‐term follow‐up MRI should be mandatory to validate the procedure. Cancer 2007 © 2007 American Cancer Society.

Gamma Knife Radiosurgery in the Management of Unusual Grade I/II Primitive Neuroepithelial Tumours of the Brain

“…This trend could suggest that multisession GKRS with the Extend System (Elekta Instrument) should be better in those patients affected with larger tumors, thus achieving an increased dose delivery to the target volume maintaining a negligible risk of permanent side effects on the surrounding normal brain tissue. Some authors (Kobayashi et al, 2001, Kim et al, 2007 propose GKRS as primary treatment without histological diagnosis when a deep-seated or critically located brain tumor showing the imaging characteristics of an unusual LGPNTs is identified. On the contrary, other collegues state that obtaining a histological diagnosis remains the main aim for rational treatment planning (Matsunaga et al, 2010;Martin et al, 2003;Yen et al, 2007;Tyler-Kabara et al, 2001;Kano et al, 2009d;Lekovic et al, 2007;Reyns et al, 2007;Dershmukh et al, 2004).…”

“…But, tumors in more than half of patients with CN cannot be completely resected. Furthermore, recurrences, even after complete resection, and tumor progression after subtotal resection have been reported up to 33% of cases (Matsunaga et al, 2010, Kim et al, 2007, Yen et al, 2007, Martin et al, 2003, Cobery et al, 2001). Finally, malignant transformation is known to occur in a few cases, resulting in tumor progression, intracerebral hemorrhage, or craniospinal dissemination (Matsunaga et al, 2010).…”

“…The results showed effective local tumor control. However, because of the benign clinical course of CN, the young mean age of the affected patients and the well-known long-term adverse effects of conventional RT, such as cognitive dysfunction and secondary tumor formation, routine use of conventional RT for residual or recurrent CN has been critized by several authors (Kim et al, 2007, Yen et al, 2007, Martin et al, 2003. The advantage of a focused radiation is that a high dose with a steep fall off in radiation can be delivered precisely in one single treatment session.…”

“…The aim of this chapter is to assess the value of GKRS in the management of such cerebral tumors. The interest of this study is founded on several observations: 1) unusual LGPNTs are rare tumours; there are a few series with at least ten reported cases, only (Hasegawa et al, 2002;Kim et al, 2007); 2) these tumors are frequently deep-seated in the brain or located in functional cerebral regions, thus gross total surgical removal may often be highly risky or impossible sometimes; 3) unusual…”

Gamma Knife Radiosurgery for Central Neurocytomas

“…2,3,[5][6][7][8][9][10][11][12][13][14]16,19,31,32,36) They are usually located in the lateral ventricles with or without extension to the third ventricles in young adults. 2,3,8,10,19) Standard initial treatment for central neurocytomas is a total resection whenever possible.…”