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At least 19 recordsLinked to original sources
PubMed2002

Radiosurgery for residual or recurrent nonfunctioning pituitary adenoma.

OBJECT: Nonfunctioning pituitary adenomas comprise approximately 30% of all pituitary tumors. The purpose of this retrospective study is to evaluate the efficacy and role of gamma knife radiosurgery (GKS) in the management of residual or recurrent nonfunctioning pituitary adenomas. METHODS: A review was conducted of the data obtained in 42 patients who underwent adjuvant GKS at the University of Pittsburgh between 1987 and 2001. Prior treatments included transsphenoidal resection, craniotomy and resection, or conventional radiotherapy. Endocrinological, ophthalmological, and radiological responses were evaluated. The duration of follow-up review varied from 6 to 102 months (mean 31.2 months). Fifteen patients were observed for more than 40 months. The mean radiation dose to the tumor margin was 16 Gy. Conformal radiosurgery planning was used to restrict the dose to the optic nerve and chiasm. Tumor control after GKS was achieved in 100% of patients with microadenomas and 97% of patients with macroadenomas. Gamma knife radiosurgery was equally effective in controlling adenomas with cavernous sinus invasion and suprasellar extension. No patient developed a new endocrinological deficiency following GKS. One patient's tumor enlarged with an associated decline in visual function. Another patient experienced a deterioration of visual fields despite a decrease in tumor size. CONCLUSIONS: Gamma knife radiosurgery can achieve tumor control in virtually all residual or recurrent nonfunctioning pituitary adenomas. Dose sparing facilitates tumor management even when the adenoma is close to the optic apparatus or invades the cavernous sinus.

Adenoma↗
PubMed2000

Gamma knife radiosurgery as a primary treatment for prolactinomas.

OBJECT: The purpose of this study was to estimate the efficacy of gamma knife radiosurgery (GKS) in controlling tumor growth and endocrinopathy associated with prolactinomas. METHODS: Between 1993 and 1997, 164 of 469 patients with pituitary adenomas treated by GKS harbored prolactinomas. The dose to the tumor margin ranged from 9 to 35 Gy (mean 31.2 Gy), and the visual pathways were exposed to a dose of less than 10 Gy. The mean tumor diameter was 13.4 mm. The mean follow-up time for 128 cases was 33.2 months (range 6-72 months). Tumor control was observed in all but two patients who underwent surgery 18 and 36 months, respectively, after GKS. Clinical cure was achieved in 67 cases. Clinical improvement was noted with a decrease in the hyperprolactinemia after GKS. Nonetheless, in 31 (29%) of 108 patients who were followed for more than 2 years no improvement in serum prolactin levels was demonstrated, although this could be normalized by bromocriptine administration after treatment. Nine infertile women became pregnant 2 to 13 months after GKS and all gave birth to normal children. There was no visual deterioration related to GKS. Five women experienced premature menopause. In these patients there was subtotal disappearance of the tumor and an empty sella developed. CONCLUSIONS: Gamma knife radiosurgery as a primary treatment for prolactinomas can be safe and effective both for controlling tumor growth and for normalization of prolactin hypersecretion. A higher margin dose (> or = 30 Gy) seemed to be associated with a better clinical outcome. Gamma knife radiosurgery may make prolactinomas more sensitive to the bromocriptine.

Humans↗
PubMed1994

Current radiosurgery practice: results of an ASTRO survey. Task Force on Stereotactic Radiosurgery, American Society for Therapeutic Radiology and Oncology.

PURPOSE: Although there is increasing interest in radiosurgery, little quantitative data regarding current patterns of radiosurgery practice are available. We developed a radiosurgery questionnaire to obtain information on radiosurgery practice. METHODS AND MATERIALS: We distributed the questionnaire to the entire membership of the American Society of Therapeutic Radiology and Oncology in early 1993. Responses were obtained from 74 facilities that practice radiosurgery, corresponding to over 6000 treatments carried out since 1983 by 135 radiation oncologists and 130 physicists. RESULTS: Most respondents were found to work within a multidisciplinary team, consisting of the following specialists (average hours devoted per patient on day of treatment in parentheses): radiation oncologist (3.8), neurosurgeon (3.2), physicist (6.1), radiologist (0.7), nurse (2.7), other (3.0). On average, neurosurgeons and nurses who perform Gamma Knife radiosurgery devote significantly more time-per-patient on the day of treatment than their peers who perform linac radiosurgery. On average, less experienced radiation oncologists and physicists (< or = 24 months experience, or < or = 50 patients treated) devote significantly more time-per-patient on the day of treatment than their more experienced peers. Although there are many more linac radiosurgery facilities than Gamma Knife facilities, on average the number of patients treated per month per facility is significantly larger at the latter. On average, follow-up responsibilities are nearly equally shared by radiation oncologists and neurosurgeons, except at Gamma Knife facilities, where neurosurgeons assume a larger percentage of follow-up responsibility. The percentages of patients treated at linac facilities for metastases or primary CNS malignancy are larger than the corresponding percentages at Gamma Knife facilities; the opposite is true for arteriovenous malformation, acoustic neuroma, and meningioma. CONCLUSION: Current radiosurgery practice usually involves a team approach, with participation of specialists from radiation oncology, neurosurgery, physics, radiology, and nursing. The average number of M.D. and Ph.D. hours required per treatment on the day of radiosurgery is high.

Canada↗
PubMed2005

Radiosurgery of small skull-base lesions. No advantage for intensity-modulated stereotactic radiosurgery versus conformal arc technique.

BACKGROUND AND PURPOSE: Intensity-modulated stereotactic radiotherapy (IMSRT) has shown the ability to conform the dose to concavities and to better avoid critical organs for large tumors. Given the availability of an electronically driven micro-multileaf collimator, both intensity-modulated stereotactic radiosurgery (IMSRS) and dynamic conformal arc (DCA) technique (DCA) can be performed at the Novalis Shaped Beam Surgery Center, University of Erlangen-Nuremberg, Germany, since 12/2002. This study evaluates both techniques in small skull-base tumors treated with radiosurgery. MATERIAL AND METHODS: Between 12/2002 and 04/2004, a total of 109 radiosurgical procedures were performed in 77 patients, equally distributed between patients with acoustic neuroma (AN), pituitary adenoma (PA) and meningeoma (M). Six index patients (n = 2 AN, n = 1 PA, n = 3 M) routinely planned for dynamic arc stereotactic radiosurgery were replanned using the IMSRS approach (BrainScan, BrainLAB, Heimstetten, Germany). The RTOG radiosurgery quality assurance guidelines, isodose volumes, doses to organs at risk (OAR), and dose delivery criteria were compared. RESULTS: DCA was superior to IMSRS for homogeneity and coverage. IMSRS could keep the high-dose-irradiated volumes (90% isodose volume) lower than DCA in the PA and AN with very small volumes, but all other lower dose volumes were larger for IMSRS. Dose maxima to OAR were higher for IMSRS. Treatment delivery time for IMSRS would clearly exceed treatment time for DCA by a factor of 2-3. The integral absorbed dose to the brain was much higher in the IMSRS than in the DCA approach (factor 2-3). CONCLUSION: RTOG radiosurgery guidelines were best met by the DCA rather than IMSRS approach for the treatment of small skull-base lesions. The IMSRS approach will increase the time for planning, dose delivery and integral dose to the brain. Thus, IMSRT techniques are recommended for fractionated stereotactic radiotherapy to larger volumes rather than for radiosurgery in small skull-base lesions.

Adenoma↗
PubMed1999

Stereotactic radiosurgery. VII. Radiosurgery versus conventionally-fractionated radiotherapy in the treatment of cavernous sinus meningiomas.

Twenty-eight patients with meningiomas involving the cavernous sinus were referred to the radiosurgical service at St. Bartholomew's Hospital 1989-1998. The majority (8/13) of patients with small (< 3 cm diameter) tumours received radiosurgery whereas the majority of large tumours (> 3 cm diameter; 12/15) received conventionally-fractionated radiotherapy. Other treatment recommendations were fractionated radiosurgery (one case) and conventionally-fractionated radiotherapy to the whole meningeal base and a radiosurgery boost (three cases). Fractionated radiosurgery is optimal where the target volume is small, but abuts critically sensitive nervous system. There have been no progressions of disease at relatively early follow-up. It is argued that subtotal excision followed by appropriate dose radiation therapy is often a strong competitor to attempted radical excision given the attendant morbidity of this latter operation for meningiomas at this site. Patients referred for radiation therapy are best served by a department with both radiosurgery and conventional radiation therapy facilities.

Adult↗
PubMed2004

Feasibility of radiosurgery for malignant brain tumors in infants by use of image-guided robotic radiosurgery: preliminary report.

OBJECTIVE: The benefits of radiation therapy are generally denied to infants with malignant brain tumors because of the risk of devastating cognitive decline. Efforts to limit this morbidity with radiosurgical techniques have not been feasible for infants because of the dual requirements of rigid head fixation and high precision. We report the radiosurgical treatment of five infants by use of a robotically controlled system without rigid head fixation. METHODS: Five infants with malignant brain tumors received radiosurgical treatment with a robotically driven linear accelerator. Immobilization was aided by general anesthesia, form-fitting head supports, face masks, and body molds. The average marginal dose was 17 +/- 2 Gy, and the average treatment volume was 18 +/- 22 ml. RESULTS: X-rays obtained during treatment revealed acceptable agreement with preoperative computed tomographic scans in all patients. In one patient, the lesion did not progress, but a distant recurrence occurred 15 months after radiosurgery and also was treated with radiosurgery. In another patient, tumor in the treated region did not progress, but recurrence elsewhere led to death 7 months after treatment. Tumor enlargement occurred in Patient 3 at 3 months posttreatment, leading to death 2 months later. Tumor size was smaller in the remaining two patients at 9 and 11 months after treatment. There has been no toxicity attributed to treatment. CONCLUSION: Radiosurgery with minimal toxicity can be delivered to infants by use of a robotically controlled system that does not require rigid fixation. A formal dose-escalation trial is under way to address dose and toxicity for infants more thoroughly.

Brain Neoplasms↗
PubMed2006

Dosimetric comparisons of helical tomotherapy treatment plans and step-and-shoot intensity-modulated radiosurgery treatment plans in intracranial stereotactic radiosurgery.

PURPOSE: To evaluate dose conformity, dose homogeneity, and dose gradient in helical tomotherapy treatment plans for stereotactic radiosurgery, and compare results with step-and-shoot intensity-modulated radiosurgery (IMRS) treatment plans. METHODS AND MATERIALS: Sixteen patients were selected with a mean tumor size of 14.65 +/- 11.2 cm3. Original step-and-shoot IMRS treatment plans used coplanar fields because of the constraint of the beam stopper. Retrospective step-and-shoot IMRS plans were generated using noncoplanar fields. Helical tomotherapy treatment plans were generated using the tomotherapy planning station. Dose conformity index, dose gradient score index, and homogeneity index were used in plan intercomparisons. RESULTS: Noncoplanar IMRS plans increased dose conformity and dose gradient, but not dose homogeneity, compared with coplanar IMRS plans. Tomotherapy plans increased dose conformity and dose gradient, yet increased dose heterogeneity compared with noncoplanar IMRS plans. The average dose conformity index values were 1.53 +/- 0.38, 1.35 +/- 0.15, and 1.26 +/- 0.10 in coplanar IMRS, noncoplanar IMRS, and tomotherapy plans, respectively. The average dose homogeneity index values were 1.15 +/- 0.05, 1.13 +/- 0.04, and 1.18 +/- 0.09 in coplanar IMRS, noncoplanar IMRS, and tomotherapy plans, respectively. The mean dose gradient score index values were 1.37 +/- 19.08, 22.32 +/- 19.20, and 43.28 +/- 13.78 in coplanar IMRS, noncoplanar IMRS, and tomotherapy plans, respectively. The mean treatment time in tomotherapy was 42 +/- 16 min. CONCLUSIONS: We were able to achieve better dose conformity and dose gradient in tomotherapy plans compared with step-and-shoot IMRS plans for intracranial stereotactic radiosurgery. However, tomotherapy treatment time was significantly larger than that in step-and-shoot IMRS.

Algorithms↗
PubMed1998

Gamma knife radiosurgery for pituitary adenomas: usefulness of combined transsphenoidal and gamma knife radiosurgery for adenomas invading the cavernous sinus.

Thirty-seven of 317 patients with pituitary adenoma who underwent transsphenoidal operation from 1989 to 1996 received adjuvant gamma knife radiosurgery. Gamma knife surgery was performed mainly in patients with endocrinologically inactive tumor for tumor regrowth invading the cavernous sinus, and in patients with endocrinologically active tumor for incomplete removal invading the cavernous sinus. The maximum radiation dose was 25-60 Gy. The periphery of the tumor usually received 50% of the maximum dose. Thirteen patients were followed up for longer than 2 years (mean 45 months) after combined therapy. Magnetic resonance imaging (MRI) showed changes in signal intensity on both T1- and T2-weighted images as early as 3 months after radiotherapy. Serial MRI showed all 13 patients had achieved excellent response. Patients with endocrinologically active tumors showed normalized hormone levels 24 months after gamma knife surgery except for one patient with acromegaly. The basal value of pituitary hormones remained normal during the follow-up period, and four female patients became pregnant without hormonal therapy. Combined transsphenoidal surgery and gamma knife radiosurgery can preserve normal pituitary function and eradicate adenoma invading the cavernous sinus.

Adenoma↗
PubMed1992

Radiosurgery and brain tolerance: an analysis of neurodiagnostic imaging changes after gamma knife radiosurgery for arteriovenous malformations.

In order to analyze complications and the factors responsible for the development of serial imaging changes after stereotactic radiosurgery for intracranial arteriovenous malformations, we reviewed serial post-treatment magnetic resonance imaging scans in 72 patients. Median follow-up was 23 months (range 12 to 35 months). Twenty patients developed post-radiosurgical imaging changes consisting of new regions of increased T2 signal on magnetic resonance imaging in brain surrounding the arteriovenous malformation (two year actuarial incidence of 31%). Imaging changes were associated with headache or new neurological deficits in nine of these 20 (45%) and remained asymptomatic in 11 (55%). Symptoms developed in three of 13 patients with imaging changes in the cerebral cortex or cerebellum, in contrast to six of seven patients who had symptoms with imaging changes in the brainstem (p = .028). The onset of imaging changes varied from five to 18 months after radiosurgery (median, 12 months). Serial follow-up scans four to 25 months after the onset of imaging changes were available for review in 16 patients. Post-radiosurgical imaging changes completely resolved within 4 to 19 months in ten patients and have not yet completely resolved after 6 to 25 months in six patients. The projected actuarial rate for resolution of imaging changes was 88%, 19 months after onset; the median time for resolution was 14 months. Univariate analysis revealed that the development of imaging changes was significantly associated with treatment volume (p = .025), the risk predicted from the integrated logistic formula (p = .042), and the number of isocenters treated (p = .042). In multivariate analysis, volume was the only factor significantly associated with the development of imaging changes.

Adolescent↗
PubMed2003

Comparison of intensity-modulated radiosurgery with gamma knife radiosurgery for challenging skull base lesions.

PURPOSE: To quantitatively compare intensity-modulated radiosurgery (IMRS) using 3-mm mini-multileaf collimation with gamma knife radiosurgery (GKRS) plans for irregularly shaped skull base lesions in direct proximity to organs at risk (OAR). METHODS AND MATERIALS: Ten challenging skull base lesions originally treated with GKRS were selected for comparison with IMRS using inverse treatment planning and 3-mm mini-multileaf collimation operating in step-and-shoot delivery mode. The lesions ranged in volume from 1.6 to 32.2 cm(3) and were treated with 9-20 GK isocenters (mean 13.2). The IMRS plans were designed with the intent to, at minimum, match the GKRS plans with regard to OAR sparing and target coverage. For each case, IMRS plans were generated using 9 coplanar, 11 equally spaced noncoplanar, and 11 OAR-avoidant noncoplanar beams; the best of these approaches with respect to target conformality, sparing of OAR, and maintaining coverage was selected for comparison with the original GKRS plan. RESULTS: Assuming no patient motion or setup error, IMRS provided comparable target coverage and sparing of OAR and an improved conformity index at the prescription isodose contour but sometimes less conformity at lower isodose contours compared with the actual GKRS plan. All IMRS plans produced less target dose heterogeneity and shorter estimated treatment times compared with the GKRS plans. CONCLUSION: Compared with GKRS for complex skull base lesions, IMRS plans using a 3-mm mini-multileaf collimator achieved comparable or sometimes improved target coverage, conformity, and critical structure sparing with shorter estimated treatment times.

Brain Neoplasms↗
PubMed1999

Stereotactic radiosurgery. VI. Posterior displacement of the brainstem facilitates safer high dose radiosurgery for clival chordoma.

The current 'best treatment method' for clival chordoma is regarded as radical surgical resection followed by radiation therapy; radiosurgery usually plays a major part in the radiation therapy programme. From primate radiation biology studies and from clinical observations, the brainstem is known to be the most radiosensitive part of the central nervous system. The tolerance of the brainstem to high single radiosurgical doses of radiation is limited (all the more so in programmes such as our own where conventionally fractionated radiotherapy precedes radiosurgery or the patient has relapsed after conventional radiotherapy--as in the patient reported here). In this report we describe the operative displacement of the brainstem posteriorly at time of resection such that the proportion of the prescribed postoperative radiosurgical dose received by the brainstem is greatly reduced (by the order of 50%). The gains perceived to accrue from this technique are quantified from isodosimetric considerations not only in dose sparing to the brainstem, but importantly in that the dose to the clival chordoma may be highly significantly increased without exceeding current accepted tolerance brainstem dose limits. Two patients have received this joint surgical/radiosurgical approach to date; the second case is presented here in detail.

Brain Stem↗
PubMed2004

Interstitial radiosurgery with the photon radiosurgery system in the minimally-invasive treatment of selected deep-seated brain tumors.

The purpose of this study was to evaluate the results of interstitial radiosurgery (IR) with Photon Radiosurgery System (PRS) in 18 patients (P) with deep-seated brain primary or secondary tumors. Follow-up varied from 2 to 53 months (mean, 13.6 mo). Seven P with glioblastomas died due to tumor progression. Five P with metastases died for systemic disease while local control was achieved in all. Six P with low-grade astrocytomas were well and imaging showed tumor control. We conclude that PRS IR is effective in the treatment of metastases while it provides lower benefit in malignant gliomas. It could play a major role in low-grade astrocytomas.

Adolescent↗
PubMed2000

Histological effects of trigeminal nerve radiosurgery in a primate model: implications for trigeminal neuralgia radiosurgery.

OBJECTIVE: Stereotactic radiosurgical treatment of the proximal trigeminal nerve is used to relieve the pain of trigeminal neuralgia. The mechanism of the radiosurgical effect is not understood. METHODS: Two adult baboons underwent stereotactic magnetic resonance imaging-guided radiosurgery, using a gamma knife. A single 4-mm isocenter was targeted to each proximal trigeminal nerve, just anterior to the pons, to deliver a maximal dose of 80 or 100 Gy (total of four nerves). A nonirradiated baboon brain and nerves served as control specimens. Six months after treatment, magnetic resonance imaging was again performed and the brains and nerves were studied using light and electron microscopy. RESULTS: Magnetic resonance imaging indicated a 4-mm-diameter area of contrast enhancement at the target site in each nerve. All irradiated nerves exhibited axonal degeneration and mild edema at the target, with remnants of some myelinated axons. Large and small myelinated and unmyelinated fibers were affected. No inflammation was observed. Nerve necrosis was identified after 100-Gy treatment. The trigeminal ganglion appeared normal. CONCLUSION: Radiosurgery at 80 Gy causes focal axonal degeneration of the trigeminal nerve. At higher doses, partial nerve necrosis is observed. We think that these effects influence the physiological features of trigeminal neuralgia.

Animals↗
PubMed2006

Stereotactic radiosurgery plus whole-brain radiation therapy vs stereotactic radiosurgery alone for treatment of brain metastases: a randomized controlled trial.

CONTEXT: In patients with brain metastases, it is unclear whether adding up-front whole-brain radiation therapy (WBRT) to stereotactic radiosurgery (SRS) has beneficial effects on mortality or neurologic function compared with SRS alone. OBJECTIVE: To determine if WBRT combined with SRS results in improvements in survival, brain tumor control, functional preservation rate, and frequency of neurologic death. DESIGN, SETTING, AND PATIENTS: Randomized controlled trial of 132 patients with 1 to 4 brain metastases, each less than 3 cm in diameter, enrolled at 11 hospitals in Japan between October 1999 and December 2003. INTERVENTIONS: Patients were randomly assigned to receive WBRT plus SRS (65 patients) or SRS alone (67 patients). MAIN OUTCOME MEASURES: The primary end point was overall survival; secondary end points were brain tumor recurrence, salvage brain treatment, functional preservation, toxic effects of radiation, and cause of death. RESULTS: The median survival time and the 1-year actuarial survival rate were 7.5 months and 38.5% (95% confidence interval, 26.7%-50.3%) in the WBRT + SRS group and 8.0 months and 28.4% (95% confidence interval, 17.6%-39.2%) for SRS alone (P = .42). The 12-month brain tumor recurrence rate was 46.8% in the WBRT + SRS group and 76.4% for SRS alone group (P<.001). Salvage brain treatment was less frequently required in the WBRT + SRS group (n = 10) than with SRS alone (n = 29) (P<.001). Death was attributed to neurologic causes in 22.8% of patients in the WBRT + SRS group and in 19.3% of those treated with SRS alone (P = .64). There were no significant differences in systemic and neurologic functional preservation and toxic effects of radiation. CONCLUSIONS: Compared with SRS alone, the use of WBRT plus SRS did not improve survival for patients with 1 to 4 brain metastases, but intracranial relapse occurred considerably more frequently in those who did not receive WBRT. Consequently, salvage treatment is frequently required when up-front WBRT is not used. TRIAL REGISTRATION: umin.ac.jp/ctr Identifier: C000000412.

Adult↗
PubMed2002

A multi-institutional review of radiosurgery alone vs. radiosurgery with whole brain radiotherapy as the initial management of brain metastases.

PURPOSE: Data collected from 10 institutions were reviewed to compare survival probabilities of patients with newly diagnosed brain metastases managed initially with radiosurgery (RS) alone vs. RS + whole brain radiotherapy (WBRT). METHODS AND MATERIALS: A database was created from raw data submitted from 10 institutions on patients treated with RS for brain metastases. The major exclusion criteria were resection of a brain metastasis and interval from the end of WBRT until RS >1 month (to try to ensure that the up-front intent was to combine RS + WBRT and that RS was not given for recurrent brain metastases). Survival was estimated using the Kaplan-Meier method from the date of first treatment for brain metastases until death or last follow-up. Survival times were compared for patients managed initially with RS alone vs. RS + WBRT using the Cox proportional hazards model to adjust for known prognostic factors or Radiation Therapy Oncology Group recursive partitioning analysis (RPA) class. RESULTS: Out of 983 patients, 31 were excluded because treatment began after 6/1/98; 159 were excluded because brain metastases were resected; 179 were excluded because there was an interval >1 month from WBRT until RS; and 45 were excluded for other reasons. Of the 569 evaluable patients, 268 had RS alone initially (24% of whom ultimately had salvage WBRT), and 301 had RS + up-front WBRT. The median survival times for patients treated with RS alone initially vs. RS + WBRT were 14.0 vs. 15.2 months for RPA Class 1 patients, 8.2 vs. 7.0 months for Class 2, and 5.3 vs. 5.5 months for Class 3, respectively. With adjustment by RPA class, there was no survival difference comparing RS alone initially to RS + up-front WBRT (p = 0.33, hazard ratio = 1.09). CONCLUSIONS: Omission of up-front WBRT does not seem to compromise length of survival in patients treated with RS for newly diagnosed brain metastases.

Aged↗
PubMed2002

Stereotactic radiosurgery XIV: The role of the haemosiderin 'ring' in the development of adverse reactions following radiosurgery for intracranial cavernous malformations: a sustainable hypothesis.

There are strong data supporting the clinical efficacy of ionizing radiation therapy in the treatment of extracranial cavernous angiomas; no unusual complications occur. There is no a priori reason to anticipate a high rate of complications following radiosurgery for brain cavernous angiomas and yet equivalent dose prescriptions (site, size and target volume) to those used for AVM are associated with a considerably higher complication rate. The observed sub-acute reactions sometimes recover with steroid therapy. Previous authors have not sought to define the aetiological basis of this observation. Haemosiderin staining of the fringe of normal brain tissue surrounding the cavernoma is a unique feature of these brain lesions and the potential radiosensitizing properties of this iron based substance, for which there is a considerable experimental and clinical observational basis for radiosensitization, are reviewed. These provide good support for the concept that this characteristic feature of brain cavernomas accounts for the higher post radiation reaction/complication rate. Treatment considerations, stemming from these observations, are suggested.

Brain Neoplasms↗
PubMed1999

Gamma Knife radiosurgery for metastatic brain tumor: the usefulness of repeated Gamma Knife radiosurgery for recurrent cases.

Forty-one patients with a total of 193 metastatic brain tumors were treated because of new lesions or in a few cases because of tumor regrowth. The management involved two to four treatments with Gamma Knife radiosurgery (GKRS). The overall median survival was 15 months. The local control rate of tumors was 89% for the first treatment and 93% for repeated treatments. Symptomatic radiation-induced edema appeared in only two cases (4.9%). Patients with metastatic brain tumors who developed new lesions after GKRS were treated with GKRS alone for subsequent lesions. It was possible to control tumors for a long period with minimal side effects. As a result, we were able to maintain the quality of life of these patients, but, the effect of GKRS in controlling tumor regrowth seemed temporary.

Actuarial Analysis↗