Saturday, March 3, 2012

CYBERKNIFE TREATMENT FOR SPINAL CORD TUMORS

Radiosurgery for spinal metastases: clinical experience in 500 cases from a single institution.
Gerszten PC, Burton SA, Ozhasoglu C, Welch WC.
SourceDepartment of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA. gersztenpc@upmc.edu

Abstract
STUDY DESIGN: A prospective nonrandomized, longitudinal cohort study.

OBJECTIVE: To evaluate the clinical outcomes of single-fraction radiosurgery as part of the management of metastatic spine tumors.

SUMMARY OF BACKGROUND DATA: The role of stereotactic radiosurgery for the treatment of spinal lesions has previously been limited by the availability of effective target immobilization and target tracking devices. Large clinical experience with spinal radiosurgery to properly assess clinical experience has previously been limited.

METHODS: A cohort of 500 cases of spinal metastases underwent radiosurgery. Ages ranged from 18 to 85 years (mean 56). Lesion location included 73 cervical, 212 thoracic, 112 lumbar, and 103 sacral.

RESULTS: The maximum intratumoral dose ranged from 12.5 to 25 Gy (mean 20). Tumor volume ranged from 0.20 to 264 mL (mean 46). Long-term pain improvement occurred in 290 of 336 cases (86%). Long-term tumor control was demonstrated in 90% of lesions treated with radiosurgery as a primary treatment modality and in 88% of lesions treated for radiographic tumor progression. Twenty-seven of 32 cases (84%) with a progressive neurologic deficit before treatment experienced at least some clinical improvement.

CONCLUSIONS: The results indicate the potential of radiosurgery in the treatment of patients with spinal metastases, especially those with solitary sites of spine involvement, to improve long-term palliation.

Source : http://www.ncbi.nlm.nih.gov/pubmed/17224814

For more information you may blog your comments or write to lakshmipriya_b@apollohospitals.com

Visual field preservation thru cyberknife radiosurgery

Visual field preservation after multisession cyberknife radiosurgery for perioptic lesions.
Adler JR Jr, Gibbs IC, Puataweepong P, Chang SD.
SourceDepartment of Neurosurgery, Stanford University Medical School, Stanford, California 94305, USA. jra@stanford.edu

Abstract
OBJECTIVE: The restricted radiation tolerance of the anterior visual pathways represents a unique challenge for ablating adjacent lesions with single-session radiosurgery. Although preliminary studies have recently demonstrated that multisession radiosurgery for selected perioptic tumors is both safe and effective, the number of patients in these clinical series was modest and the length of follow-up limited. The current retrospective study is intended to help address these shortcomings.

METHODS: Forty-nine consecutive patients with meningioma (n = 27), pituitary adenoma (n = 19), craniopharyngioma (n = 2), or mixed germ cell tumor (n = 1) situated within 2 mm of a "short segment" of the optic apparatus underwent multisession image-guided radiosurgery at Stanford University Medical Center. Thirty-nine of these patients had previous subtotal surgical resection, and six had previously been treated with conventional fractionated radiotherapy (6). CyberKnife radiosurgery was delivered in two to five sessions to an average tumor volume of 7.7 cm3 and a cumulative average marginal dose of 20.3 Gy. Formal visual testing and clinical examinations were performed before treatment and at follow-up intervals beginning at 6 months.

RESULTS: After a mean visual field follow-up of 49 months (range, 6-96 mo), vision was unchanged postradiosurgery in 38 patients, improved in eight (16%), and worse in three (6%). In each instance, visual deterioration was accompanied by tumor progression that ultimately resulted in patient death. However, one of these patients, who had a multiply recurrent adrenocorticotropic hormone-secreting pituitary adenoma, initially experienced early visual loss without significant tumor progression after both a previous course of radiotherapy and three separate sessions of radiosurgery. After a mean magnetic resonance imaging follow-up period of 46 months, tumor volume was stable or smaller in all other cases. Two patients died of unrelated nonbrain causes.

CONCLUSION: Multisession radiosurgery resulted in high rates of tumor control and preservation of visual function in this group of perioptic tumors. Ninety-four percent of patients retained or improved preradiosurgical vision. This intermediate-term experience reinforces the findings from earlier studies that suggested that multisession radiosurgery can be a safe and effective alternative to either surgery or fractionated radiotherapy for selected lesions immediately adjacent to short segments of the optic apparatus.

Source : http://www.ncbi.nlm.nih.gov/pubmed/18596432

For more information you may blog your comments or write to lakshmipriya_b@apollohospitals.com