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At least 253 records · Page 14Linked to original sources
PubMed2001

Image-guided hypo-fractionated stereotactic radiosurgery to spinal lesions.

OBJECTIVE: This article demonstrates the technical feasibility of noninvasive treatment of unresectable spinal vascular malformations and primary and metastatic spinal tumors by use of image-guided frameless stereotactic radiosurgery. METHODS: Stereotactic radiosurgery delivers a high dose of radiation to a tumor volume or vascular malformation in a limited number of fractions and minimizes the dose to adjacent normal structures. Frameless image-guided radiosurgery was developed by coupling an orthogonal pair of x-ray cameras to a dynamically manipulated robot-mounted linear accelerator that guides the therapy beam to treatment sites within the spine or spinal cord, in an outpatient setting, and without the use of frame-based fixation. The system relies on skeletal landmarks or implanted fiducial markers to locate treatment targets. Sixteen patients with spinal lesions (hemangioblastomas, vascular malformations, metastatic carcinomas, schwannomas, a meningioma, and a chordoma) were treated with total treatment doses of 1100 to 2500 cGy in one to five fractions by use of image-guided frameless radiosurgery with the CyberKnife system (Accuray, Inc., Sunnyvale, CA). Thirteen radiosurgery plans were analyzed for compliance with conventional radiation therapy. RESULTS: Tests demonstrated alignment of the treatment dose with the target volume within +/-1 mm by use of spine fiducials and the CyberKnife treatment planning system. Tumor patients with at least 6 months of follow-up have demonstrated no progression of disease. Radiographic follow-up is pending for the remaining patients. To date, no patients have experienced complications as a result of the procedure. CONCLUSION: This experience demonstrates the feasibility of image-guided robotic radiosurgery for previously untreatable spinal lesions.

Adolescent↗
PubMed2002

Repeat radiosurgery for refractory trigeminal neuralgia.

OBJECTIVE: Stereotactic radiosurgery has become an important and minimally invasive alternative for patients with refractory trigeminal neuralgia. When a second procedure is necessary, the outcomes are unknown. The degree of pain relief and morbidity after repeat radiosurgery were studied. METHODS: Thirty-one patients underwent a second gamma knife radiosurgery procedure because of unsatisfactory or unsustained relief of pain after the first procedure. Twenty-seven patients were assessable at median follow-up periods of 42.7 and 20.4 months after the first and second procedures, respectively. Most patients had undergone multiple previous operations of other types (microvascular decompression, radiofrequency rhizotomy, glycerol rhizotomy, balloon compression). The median target doses of the first and second radiosurgeries were 75 and 64 Gy, respectively. All patients were evaluated by a physician who did not participate in patient treatment. RESULTS: After the first radiosurgical procedure, 13 patients had an excellent response initially (complete relief without any medication), 3 had a good response (complete relief with some medication), 7 had a fair response (>50% relief), and 4 had a poor response (<50% pain relief or treatment failure). Repeat radiosurgery was performed in patients with recurrent or residual pain. After the second radiosurgical procedure, 5 patients had an excellent response, 8 had a good response, 10 had a fair response, and 4 had a poor response. Thirteen patients (48%) achieved complete pain relief (with or without medication). Two patients (7.4%) experienced new sensory symptoms after the first radiosurgical procedure, and three (12.7%, actuarial) experienced new sensory symptoms after the second procedure. CONCLUSION: Repeat radiosurgery provided a similar rate of pain relief as the first procedure, despite a modest dose reduction. The risk of new sensory symptoms was increased, but no other morbidity was identified. For patients who experience recurrent pain and choose to undergo a second procedure, our current procedure is to deliver a maximum dose of 50 to 60 Gy to a trigeminal target anterior to the root entry zone near the entrance of the nerve beneath the petrous dura.

Adult↗
PubMed2002

The role of radiosurgery for the treatment of pineal parenchymal tumors.

OBJECTIVE: Radiosurgery is an appealing alternative management strategy for selected patients with biopsy-proved pineal parenchymal tumors. The purpose of this report was to clarify its role in conjunction with other surgical, radiation, and medical approaches. METHODS: We retrospectively evaluated 16 patients who had undergone radiosurgery as the primary or adjuvant treatment for pineal parenchymal tumors. Ten patients (62.5%) had pineocytomas, two (12.5%) had mixed pineocytoma and pineoblastoma, and four (25%) had pineoblastomas. The mean marginal dose was 15 Gy, and the mean tumor volume was 5.0 cm(3). The mean follow-up periods from the time of diagnosis or the time of radiosurgery were 61 and 52 months, respectively. RESULTS: The overall actuarial 2- and 5-year survival rates after diagnosis were 75.0 and 66.7%, respectively. In 14 patients who were evaluated with imaging, 4 (29%) demonstrated complete remission, 8 (57%) had partial remission, 2 (14%) had no change, and no patient had local progression. The local tumor control rate (complete remission, partial remission, or no change) was 100%. Five patients died during follow-up. One patient with a pineocytoma and three patients with pineoblastomas died secondary to leptomeningeal or extracranial spread tumor. No cause of death was established for one patient. Two patients developed adverse radiation effects after radiosurgery. CONCLUSION: Our initial experience suggests that stereotactic radiosurgery is a valuable primary management modality for patients with pineocytomas. As adjuvant therapy, radiosurgery may be used to boost local tumor dose during multimodality management of malignant pineal parenchymal tumors.

Adolescent↗
PubMed2007

Radiosurgery for spinal metastases: clinical experience in 500 cases from a single institution.

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.

Adult↗
PubMed2001

Factors influencing early complications following Gamma Knife radiosurgery. A prospective study.

PURPOSE: The factors influencing early complications following Gamma Knife radiosurgery have not been definitely established. We report a prospective study evaluating the incidence of early complications (occurring within 3 months of radiosurgery) and various factors associated with early complications following stereotactic Gamma Knife radiosurgery for intracranial lesions. PATIENTS AND METHODS: Seventy-nine previously unirradiated consecutive adult patients (82 lesions: arteriovenous malformations 35, benign tumors 43, metastases 4) treated by Gamma Knife radiosurgery were studied between May 1997 and August 1998. The median target volume was 4.8 cm(3). The median dose of 15 Gy was prescribed to the 50% isodose. Patients were evaluated clinically and radiologically (with CT/MRI/SPECT) at 3-month intervals for the 1st year and 6 monthly thereafter. Complications were further divided as immediate (occurring within 24 h) or acute (occurring from 1 day to 3 months). RESULTS: Early complications were observed in 19/79 (24.0%) patients. These included immediate in 10 (12.7%) and acute complications in 9 (11.3%) patients and were characterized by headache, nausea/vomiting, vertigo and seizures. No severe early complications were observed. Radiological changes in the form of perilesional edema were seen in 8/82 (9.8%) lesions. Maximum target diameter >25 mm was the only factor significantly associated with early complications by univariate analysis (p = 0.0335). Multivariate analysis revealed maximum target diameter >25 mm and prescribed dose >20 Gy to be significantly associated with early complications (p = 0.0442 and p = 0.0083, respectively). CONCLUSION: Up to one fourth of the patients undergoing Gamma Knife radiosurgery for intracranial lesions can experience self-limiting early toxicity. The selection of targets with small diameter and volume may reduce the risk of early complications following Gamma Knife radiosurgery.

Adult↗
PubMed2002

Stereotactic radiosurgery for well-circumscribed fibrillary grade II astrocytomas: an initial experience.

OBJECTIVE: To examine the role of stereotactic radiosurgery in the management of patients with progressive, well-circumscribed grade II fibrillary astrocytomas. METHODS: During a 13-year interval, 12 patients (median age: 25 years) required multimodality management for recurrent or unresectable World Health Organization (WHO) grade II fibrillary astrocytomas. Tumors involved the brainstem (n = 4), thalamus (n = 1), cerebellum (n = 1), frontal lobe (n = 4), temporal lobe (n = 1), and parietal lobe (n = 1). Diagnosis was confirmed by stereotactic biopsy (n = 5), partial resection (n = 5), and near total resection (n = 2). Multimodality management of patients prior to radiosurgery included fractionated radiation therapy (n = 4), stereotactic cyst drainage (n = 1), and ventriculoperitoneal shunt placement (n = 2). Tumor volumes varied from 1.2 to 45.1 cm(3). The median radiosurgical dose to the tumor margin was 16 Gy. RESULTS: After radiosurgery, serial imaging showed complete tumor resolution in 1 patient, reduced tumor volume in 4, stable tumor volume in 3, and delayed tumor progression in 4 (3 patients with increase in cyst size only). Therapy after radiosurgery included additional cytoreductive surgery (n = 1) for recurrence of a higher grade tumor, stereotactic cyst aspiration (n = 1), and stereotactic intracavitary irradiation (n = 1). All patients were alive at a median follow-up of 52 months after radiosurgery and 103 months after diagnosis. In 8 patients, follow-up lasted more than 60 months. CONCLUSION: Stereotactic radiosurgery is a potential alternative or adjunctive strategy in the management of selected patients with WHO grade II fibrillary astrocytomas.

Adolescent↗
PubMed2006

An evidence-based medicine review of stereotactic radiosurgery.

BACKGROUND: Stereotactic radiosurgery has been increasingly utilized to manage a wide variety of indications including vascular malformations, benign and malignant tumors, and functional disorders. METHODS: Review of the recent literature on stereotactic radiosurgery by evidence-based standards. RESULTS: The vast majority of published papers on stereotactic radiosurgery is of rather poor quality (level 3 or below). Two studies provide level 1 evidence showing an improvement in local tumor control or survival for patients with 1-3 brain metastases having radiosurgery in conjunction with whole brain radiation therapy when compared to patients having whole brain radiation therapy alone. One randomized trial found no improvement in facial pain outcomes for trigeminal neuralgia patients having a longer segment of the nerve irradiated. CONCLUSION: For a variety of reasons it is unlikely that randomized clinical trials will be performed to evaluate the clinical usefulness of stereotactic radiosurgery. Nonetheless, the preponderance of level 3 information supports the role of radiosurgery as either an adjunct or alternative to surgical resection or fractionated radiation therapy.

Cardiovascular Abnormalities↗
PubMed1995

Cranial nerve preservation after stereotactic radiosurgery of intracanalicular acoustic tumors.

We reviewed our initial stereotactic radiosurgery experience in 10 patients with intracanalicular acoustic tumors managed by radiosurgery during a 5-year period. These patients constitute 4.7% of acoustic tumor patients who underwent Gamma Knife radiosurgery during this period. Tumor volume stabilization was achieved in 8. Two patients had initial growth followed by delayed growth arrest. Preservation of preoperative hearing was achieved in all patients in the immediate postoperative period and in 8 of 10 at 1 year. No patient had developed facial or trigeminal nerve dysfunction at the last follow-up, which varied from 3 to 64 months (mean 25 months). Tumor growth was delayed in 2 patients, but neither has required delayed microsurgical resection. All patients returned to their preoperative functional status within 3-5 days after radiosurgery. Stereotactic radiosurgery using the Gamma Knife is a safe and effective management strategy for intracanalicular acoustic tumor patients. Our initial results indicate that high cranial nerve preservation rates and a rapid return to previous activity and employment are benefits of radiosurgery.

Adult↗
PubMed1994

Stereotactic radiation therapy and radiosurgery.

In all stereotactic irradiation procedures, a high dose is delivered to a relatively small target volume. Whether fractionated stereotactic radiotherapy is preferable (based on a therapeutic ratio) or a radiosurgical method (aiming at the precise and complete destruction of a tissue volume) depends on the definition and composition of the target. The methodologies can be grouped in closed-skull external focussed beam stereotactic radiosurgery/radiotherapy and in stereotactic implantation/injection of radiation sources. Although originally developed to treat functional disorders of the brain, stereotactic radiosurgery has been used most successfully for over 4 decades to treat cerebral arteriovenous malformations. Complete obliteration ranges from 30 to 50% after 1 year are reported. At 2 years the results range from 72 to 90%. Clearly the outcome is influenced by patient selection. In the treatment of acoustic neurinomas follow-up data of larger series of radiosurgery show that the treatment performed under local anesthesia on an outpatient basis becomes comparable with the best microsurgery data. Using multiple isocenters and MR localization tumor growth control is achieved in more than 90% of cases, with hearing preservation of approximately 50%. Pituitary tumors with Cushing's syndrome, acromegaly, Nelson's syndrome, prolactinomas and nonsecreting adenomas have been treated with various stereotactic irradiation methods. Further refinement of both localization techniques, dose distribution and beam manipulation will make radiosurgery an attractive modality because of its noninvasive character and low morbidity. Only a small subgroup of patients with low-grade gliomas are candidates for stereotactic localized irradiation treatment, namely those with circumscribed tumors with only limited spread of tumor cells into the periphery. For this subgroup, which usually comprises not more than 25% of all low-grade gliomas, the results from interstitial radiosurgery compete with surgical resection. Apart from the possibility to define the borders of the treatment volume with serial stereotactic biopsies, there are dosimetric advantages of interstitial radiosurgery. Local single high-dose treatment remains controversial for highly malignant infiltrative tumors, and significant treatment benefit remains to be documented. Radiosurgery can be used to effectively treat solitary brain metastases with less invasiveness and dissection of normal tissue, and with lower morbidity and less expense than open surgery.

Brain Neoplasms↗
PubMed1992

Radiosurgery as part of the initial management of patients with malignant gliomas.

PURPOSE: Between May 1988 and May 1991, 41 patients with malignant gliomas were enrolled onto a prospective study designed to evaluate the role of radiosurgery as a component of initial management. PATIENTS AND METHODS: Thirty-seven patients underwent radiosurgery according to the protocol and were assessable for survival and complications of treatment. Diagnoses included glioblastoma multiforme (GBM) in 23 (62%) cases and anaplastic astrocytoma in 14 (38%) cases. In 20 (54%) cases, surgical resection was attempted initially, whereas 17 (46%) patients underwent biopsy only. Patients in the study group received external-beam radiotherapy that consisted of 5,940 cGy given in 33 fractions to partial brain fields that encompassed the primary tumor with a 3 to 4 cm margin. Radiosurgery, used as a technique for boosting the dose to any residual contrast-enhancing mass lesion, was given 2 to 4 weeks after the completion of conventional radiotherapy. Minimum radiosurgical doses ranged from 1,000 to 2,000 cGy (median, 1,200 cGy), whereas maximum doses ranged from 1,250 to 2,500 cGy (median, 1,500 cGy). The median tumor volume at the time of radiosurgery was 4.8 cm3 (range, 1.2 to 72 cm3). Adjuvant chemotherapy was not given. RESULTS: After a median follow-up of 19 months, only nine of 37 (24%) patients have died. Six patients (all glioblastoma multiforme) died of recurrent tumor, whereas death was attributable to complications of treatment in two cases and intercurrent disease in one case. Four patients with recurrent tumor failed at the margins of the radiosurgical treatment volume, whereas two patients progressed locally. One patient is alive with local and marginal failure. Seven (19%) patients underwent reoperation at a median time of 5 months (range, 1 to 14 months) after radiosurgery. CONCLUSION: We conclude that radiosurgery is a useful adjunct to other modalities in the initial management of patients with small, radiographically well-defined malignant gliomas.

Actuarial Analysis↗
PubMed1995

Stereotactic radiosurgery for recurrent malignant gliomas.

PURPOSE: To evaluate the role of stereotactic radiosurgery in the management of recurrent malignant gliomas. PATIENTS AND METHODS: We treated 35 patients with large (median treatment volume, 28 cm3) recurrent tumors that had failed to respond to conventional treatment. Twenty-six patients (74%) had glioblastomas multiforme (GBM) and nine (26%) had anaplastic astrocytomas (AA). RESULTS: The mean time from diagnosis to radiosurgery was 10 months (range, 1 to 36), from radiosurgery to death, 8.0 months (range, 1 to 23). Twenty-one GBM (81%) and six AA (67%) patients have died. The actuarial survival time for all patients was 21 months from diagnosis and 8 months from radiosurgery. Twenty-two of 26 patients (85%) died of local or marginal failure, three (12%) of noncontiguous failure, and one (4%) of CSF dissemination. Age (P = .0405) was associated with improved survival on multivariate analysis, and age (P = .0110) and Karnofsky performance status (KPS) (P = .0285) on univariate analysis. Histology, treatment volume, and treatment dose were not significant variables by univariate analysis. Seven patients required surgical resection for increasing mass effect a mean of 4.0 months after radiosurgery, for an actuarial reoperation rate of 31%. Surgery did not significantly influence survival. At surgery, four patients had recurrent tumor, two had radiation necrosis, and one had both tumor and necrosis. The actuarial necrosis rate was 14% and the pathologic findings could have been predicted by the integrated logistic formula for developing symptomatic brain injury. CONCLUSION: Stereotactic radiosurgery appears to prolong survival for recurrent malignant gliomas and has a lower reoperative rate for symptomatic necrosis than does brachytherapy. Patterns of failure are similar for both of these techniques.

Actuarial Analysis↗
PubMed1993

Stereotactic radiosurgery: at the threshold or at the crossroads?

More than 15,000 patients worldwide have undergone stereotactic radiosurgery since the technique was first described in 1951. Over 6000 of these patients had arteriovenous malformations, usually relatively small. Increasingly, patients with benign and malignant brain tumors have had radiosurgery as an alternative to microsurgical removal. The role of radiosurgery as a tool for functional neurosurgery is being evaluated further. Numerous studies over the past 10 years have examined the benefits and risks of radiosurgery performed with various devices (cyclotron-generated particle beams, the multisource cobalt-60 gamma knife, and modified linear accelerators). As radiosurgical centers continue to proliferate, often without appropriate regulatory review, lamentable lapses in appropriate patient selection, quality assurance, training, and results analysis may ensue. Critical clinical and radiobiological questions (dose, histology, and volume variables) remain to be answered in appropriate studies; these needs can no longer be ignored by governmental funding sources. Stereotactic radiosurgery is a multidisciplinary field, requiring the leadership of neurological surgeons in cooperation with radiation oncologists, radiologists, and medical physicists. For many indications, stereotactic radiosurgery appears poised at both the threshold and at the crossroads. As clinical application progresses, continued dialogue between neurological surgeons and their professional colleagues is necessary to guide proper patient management decisions.

Brain Neoplasms↗
PubMed1994

Patient outcomes after stereotactic radiosurgery for "operable" arteriovenous malformations.

To define the outcomes after stereotactic radiosurgery performed for smaller volume arteriovenous malformations (AVMs) that are potentially suitable for surgical removal, we retrospectively reviewed our 4-year experience in 65 patients who declined microsurgery. All 65 patients had Spetzler-Martin Grade I or II AVMs and a minimum follow-up of 24 months (median, 29 mo). Symptomatic improvement after radiosurgery occurred in 52% of patients with seizures and in 63% of patients with headaches. The annual risk of AVM hemorrhage during the latency interval after radiosurgery was 3.7%. Five patients (7.7%) had a subsequent hemorrhage (all within 8 mo of radiosurgery); two died, and three recovered (one after hematoma evacuation and two with conservative management). Forty-seven patients (72%) returned to their previous employment status or activity level within 1 week of radiosurgery (92% within 1 yr). No patient suffered radiation-related complications. Twenty-seven (84%) of 32 patients evaluated by postradiosurgical angiography had complete AVM obliteration. Radiosurgery is an effective and less invasive management strategy for Grade I or II AVM patients who are either medically unsuitable for or unwilling to undergo surgical removal. The risk of AVM hemorrhage during the latency interval until obliteration occurs appears to be no different than the natural history of untreated AVMs. These results (including hemorrhage prevention and symptom amelioration) indicate that the conservative management of small AVMs can rarely be justified.

Adolescent↗
PubMed1995

Preliminary clinical experience with linear accelerator-based spinal stereotactic radiosurgery.

A prototype device called an extracranial stereotactic radiosurgery frame was used to deliver stereotactic radiosurgery, with a modified linear accelerator, to metastatic neoplasms in the cervical, thoracic, and lumbar regions in five patients. In all patients, the neoplasms had failed to respond to spinal cord tolerance doses delivered by standard external fractionated radiation therapy to a median dose of 45 Gy (range, 33-65 Gy/11-30 fractions). The tumors were treated with single-fraction stereotactic radiosurgery with the spinal stereotactic frame for immobilization, localization, and treatment. The median number of isocenters was one (range, one to five) with a median single fraction dose of 10 Gy (range, 8-10 Gy) with median normalization to 80% isodose contour (range, 80-160%). There has been a single complication of esophagitis to date from radiosurgery of a tumor involving the C6-T1 segments; the esophagitis resolved with medical therapy. Median follow-up in this group of patients has been 6 months (range, 1-12 mo). To date, there has been no radiographic or clinical progression of the treated tumor in any patient. Two patients have died from systemic metastatic disease. In the three surviving patients, there has been computed tomographic- or magnetic resonance-documented regression of the treated tumor with a decrease of thecal sac compression with a median follow-up of 6 months (range, 3-14 mo). These five patients represent the first clinical application of stereotactic radiosurgery in the spine. The results suggest that extracranial radiosurgery may be suitable for the treatment of paraspinal neoplasms after external fractionated radiation therapy, even in the face of spinal cord compression.

Adolescent↗
PubMed2004

Toward an expanded view of radiosurgery.

Radiosurgery and radiotherapy were originally distinguished on the basis of the manner in which they protected normal tissues from radiation injury. Radiosurgery does so by precise targeting of cross-fired radiation beams to abnormal tissue, with abrupt falloff of radiation doses to surrounding normal tissue. Radiotherapy was historically less concerned with targeting accuracy and anatomic precision; normal tissues were protected by dividing doses into multiple fractions separated by time to allow recovery of normal tissues. By this means, radiotherapy applied radiobiological principles to disrupt dividing cells selectively. Despite the development of computer-based, image-guided frameless technology that eliminates the necessity to perform radiosurgery in a single session, there are some who still insist that radiosurgery be distinguished from radiotherapy on the basis of whether treatment is delivered in a single session. Here, we propose that this definition of radiosurgery is needlessly restrictive and that staging or hypofractionation of radiosurgical treatment permits the limited application of radiobiological principles of radiotherapy to improve radiosurgical treatment. We therefore define radiosurgery as a procedure that involves the active participation of a surgeon and in which spatially accurate and highly conformal doses of radiation are targeted at well-defined structures with an ablative intent.

Radiosurgery↗
PubMed2005

Radiosurgery for cranial base chordomas and chondrosarcomas.

OBJECTIVE: To evaluate the efficacy and toxicity of radiosurgery in the treatment of cranial base chordoma and chondrosarcoma. METHODS: We reviewed 29 patients with cranial base chordoma (n = 25) or chondrosarcoma (n = 4) who underwent stereotactic radiosurgery between September 1990 and December 2002. The median patient age was 45 years (range, 10-81 yr). Nineteen patients also had radiation therapy before or in conjunction with radiosurgery (median dose, 50.4 Gy). The median tumor volume was 14.4 cm3 (range, 0.6-65.1 cm3). The median tumor margin dose was 15 Gy (range, 10-20 Gy); the median maximum radiation dose was 30 Gy (range, 20-40 Gy). Median clinical and imaging follow-up periods were 4.8 and 4.5 years, respectively. RESULTS: Seven chordoma patients (28%) had tumor progression (in-field, n = 3; out-of-field, n = 4), whereas 18 had stable disease or tumor shrinkage. No patient with a chondroid chordoma had tumor enlargement. The actuarial tumor control rates were 89 and 32% at 2 and 5 years, respectively. All 4 patients with chondrosarcoma had tumor control. Clinically, 7 patients (24%) had improvement of pretreatment symptoms, 16 (55%) remained stable, and 6 (21%) worsened. Three patients with tumor progression died. Ten patients (34%) had radiation-related complications. Complications included cranial nerve deficits (n = 6), radiation necrosis (n = 5), and pituitary dysfunction (n = 3). Patients having radiosurgery alone had no toxicity. CONCLUSION: Cranial base chordomas and chondrosarcomas remain a formidable management challenge. Radiosurgery as an adjunct to surgical resection provides in-field tumor control for some patients, but radiation-related complications are relatively high, especially when radiosurgery is combined with fractionated radiation therapy.

Chondrosarcoma↗
PubMed2005

Gamma knife radiosurgery in brain metastases from testicular tumors.

To our knowledge, there are no published reports on the effectiveness of radiosurgery in the management of brain metastases from testicular nonseminomatous germ cell tumor. The authors evaluate the results of gamma knife (GK) treatment in three patients with these unusual intracranial lesions. Between April 1995 and July 2001, three patients with brain metastasis from testicular nonseminomatous germ cell tumor underwent adjuvant radiosurgery at our department. The primary tumor had been surgically removed in all cases. At diagnosis, one patient was stage IB and two were stage III poor risk. Chemotherapy and whole brain radiotherapy were administered before radiosurgery in all cases. Pre-GK radiotherapy was administered with a daily fraction dosage of 1.8-2.0 Gy. The indications for radiosurgery were tumor volume <20 cm3, microsurgery too risky, refusal of surgery. All the lesions were located in eloquent brain areas. Post-GK high-dose chemotherapy with autologous peripheral-blood stem-cell rescue was administered in two cases due to systemic recurrence of the disease. All patients are still alive with a median and mean follow-up period after radiosurgery of 63 and 68.3 mo, respectively. They had no neurological deficits at the latest examination. Neuroradiological follow-up invariably showed tumor growth control (complete response in two cases and partial response in one) with typically delayed post-radiosurgical imaging changes (transient in two cases and long-lasting in one). In conclusion, GK seems to be highly effective and safe in brain metastases from testicular nonseminomatous germ cell tumor. In cases with diffuse metastatic brain involvement, the whole brain radiotherapy preceding radiosurgery should be delivered with 1.8 Gy daily fraction to prevent the risk of long-lasting post-radiosurgical imaging changes.

Adolescent↗
PubMed1996

Gamma knife radiosurgery for brain tumors: postirradiation volume changes compared with preradiosurgical growth fractions.

The postradiosurgical volume changes were compared with preradiosurgical growth fractions defined as the tumor doubling time and/or MIB-1 staining index in 14 patients who underwent gamma knife radiosurgery for treatment of various brain tumors. The mean preradiosurgical observation period using neuroimaging techniques was 750 days (range 80-2967 days), and the mean follow-up period after radiosurgery was 664 days (range 328-1100 days). There were four neurinomas, three meningiomas, two craniopharyngiomas, two gliomas, one hemangioblastoma, one pituitary tumor, and one intracranially infiltrative lacrimal gland tumor. The mean patient age at the time of radiosurgery was 52 years (range 8-81 yrs). There were eight males and six females. Following gamma knife radiosurgery, the mean tumor half time was estimated to be 789 days (range 124-2101 days), and the volume reduction against the preradiosurgical tumor volume ranged from 6.3% to 76.1%. This study demonstrates that gamma knife radiosurgery can control tumor growth despite the lack of a correlation with preradiosurgical tumor growth or staining indices for MIB-1. Analyses of this type are essential to show that an "unchanged tumor volume" as demonstrated by postradiosurgery follow-up neuroimaging can be regarded as showing successful radiosurgery.

Adolescent↗