A multiinstitutional outcome and prognostic factor analysis of radiosurgery for resectable single brain metastasis

Local control of brain metastases by stereotactic radiosurgery in relation to dose to the tumor margin

OBJECT

The maximal tolerated dose (MTD) for stereotactic radiosurgery (SRS) for brain tumors was established by the Radiation Therapy Oncology Group (RTOG) in protocol 90-05, which defined three dose groups based on the maximal tumor diameter. The goal in this retrospective study was to determine whether differences in doses to the margins of brain metastases affect the ability of SRS to achieve local control.

METHODS

Between 1997 and 2003, 202 patients harboring 375 tumors that met study entry criteria underwent SRS for treatment of one or multiple brain metastases. The median overall follow-up duration was 10.7 months (range 3-83 months). A dose of 24 Gy to the tumor margin had a significantly lower risk of local failure than 15 or 18 Gy (p = 0.0005; hazard ratio 0.277, confidence interval [CI] 0.134-0.573), whereas the 15- and 18-Gy groups were not significantly different from each other (p = 0.82) in this regard. The 1-year local control rate was 85% (95% CI 78-92%) in tumors treated with 24 Gy, compared with 49% (CI 30-68%) in tumors treated with 18 Gy and 45% (CI 23-67%) in tumors treated with 15 Gy. Overall patient survival was independent of dose to the tumor margin.

CONCLUSIONS

Use of the RTOG 90-05 dosing scheme for brain metastases is associated with a variable local control rate. Tumors larger than 2 cm are less effectively controlled than smaller lesions, which can be safely treated with 24 Gy. Prospective evaluations of the relationship between dose to the tumor margin and local control should be performed to confirm these observations.

Gamma-Knife radiosurgery in the management of melanoma patients with brain metastases: A series of 106 patients without whole-brain radiotherapy

PURPOSE

To assess retrospectively a strategy that uses Gamma-Knife radiosurgery (GKR) in the management of patients with brain metastases (BMs) of malignant melanoma (MM).

METHODS

GKR without whole-brain radiotherapy (WBRT) was performed for patients with Karnofsky Performance Status (KPS) of 60 or above who harbored 1 to 4 BMs of 30 mm or less and was repeated as often as needed. Survival was assessed in the whole population, whereas local-control rates were assessed for patients with follow-up longer than 3 months.

RESULTS

A total of 221 BMs were treated in 106 patients; 61.3% had a single BM. Median survival from the time of GKR was 5.09 months. Control rate of treated BMs was 83.7%, with 14% of complete response (14 BMs), 42% of partial response (41 BMs), and 43% of stabilization (43 BMs). In multivariate analysis, survival prognosis factors retained were KPS greater than 80, cortical or subcortical location, and Score Index for Radiosurgery (SIR) greater than 6. On the basis of KPS, BM location, and age, a score called MM-GKR, predictive of survival in our population, was defined.

CONCLUSION

Gamma-Knife radiosurgery provides a surgery-like ability to obtain control of a solitary BM and could be consider as an alternative treatment to the combination of GKR+WBRT as a palliative strategy. MM-GKR classification is more adapted to MM patients than are SIR, RPA and Brain Score for Brain Metastasis.

Prognostic factors affecting the outcome of brain metastases from breast cancer

GOALS OF WORK

The purpose of this study is to analyze the overall survival rate of patients with brain metastases from breast cancer and to determine prognostic factors affecting outcomes of these patients.

PATIENTS AND METHODS

From July 1988 to December 2004, 48 female patients with brain metastases from breast cancer underwent full-dose whole-brain radiotherapy (WBRT). In these patients we evaluated the significance of the following factors in predicting the survival rate after WBRT: age, extracranial metastases, number of brain metastases, total dose of WBRT, Karnofsky performance status (KPS), and Radiation Therapy Oncology Group recursive partitioning analysis (RPA) class.

RESULTS

The median overall survival rate was 7.3 months. The 1- and 2-year overall survival rates were 37 and 20%, respectively. In univariate analysis, KPS (p<0.0001), number of lesions of brain metastases (p=0.0149), age (p=0.0452), and RPA class (p<0.0001) were statistically significant prognostic factors for overall survival. In multivariate analysis, KPS (p<0.001) and number of brain metastases (p=0.039) were significant prognostic factors for overall survival.

CONCLUSIONS

Survival of breast cancer patients with brain metastases treated with WBRT is poor. To improve survival, enrollment of more patients with brain metastases from breast cancer for prospective trials involving a multimodality approach that combines radiation and systemic therapies based on appropriate patient triage is warranted.

Resectable brain metastases

Brain metastases are the most common brain tumors seen in clinical practice, comprising well over half of all brain tumors. For many years, surgical resection of brain metastases was considered a form of palliative therapy only, but more recently it has been shown to have a more important role in extending survival in appropriately selected patients. Newer surgical techniques have helped to reduce the morbidity associated with tumor resection. Although randomized studies have demonstrated the need for postoperative whole-brain radiotherapy, there remains interest in the use of other surgical adjuncts to delay or eliminate the need for fractionated radiotherapy. The use of various treatment modalities, particularly image-guided surgery and stereotactic radiosurgery, allows clinicians who are focused on the treatment of brain metastases to achieve superior levels of tumor control within the brain. As a result, overall survival is much more dependent on the status of the patient's systemic disease.

Current treatment approaches to surgery for brain metastases

The role for surgical treatment of brain metastases continues to evolve. Data have demonstrated survival and quality-of-life benefits for surgical treatment of appropriate lesions in selected patients. With improvements in surgical technique, along with therapeutic improvements in the management of systemic cancers, more patients are now eligible for surgical resection. Selection of patients for surgical treatment depends on performance status, size, location, and number of brain lesions, as well as the status of systemic disease. Although surgery has traditionally been performed for patients with a single brain metastasis, an increasing number of patients with multiple brain metastases may also be treated surgically. Surgical techniques, such as image guidance, intraoperative ultrasound, functional neuronavigation, cortical mapping, and awake craniotomies, have expanded the scope of lesions that can be removed safely to optimize outcomes. Seizures, peritumoral edema, and venous thromboembolic disease all contribute significantly to surgical morbidity and mortality and thus require aggressive treatment around the time of the surgical procedure to improve the quality of life and maximize survival time.

An era of rapid advancement: diagnosis and treatment of metastatic brain cancer

The past decade has been marked by significant improvements in the survival of patients with metastatic brain tumors, but the management of this disease presents a continuing challenge because of the varied nature of brain metastases and the limited survival time. Brain metastases are becoming more prevalent because of improvements in the treatment of extracranial lesions; this paradox brought together a seven-member multidisciplinary panel to discuss some of the most promising developments in imaging, surgical, and therapeutic techniques for metastatic brain tumors, and to address the perplexing challenges that remain. Their analyses are captured in this supplement, which begins here with an overview of metastatic brain cancer.

Current treatment paradigms for the management of patients with brain metastases

Brain metastases continue to be a major and growing challenge in oncology, but recent advances in surgery, radiosurgery, and chemotherapy have broadened the number of treatment options. Current approaches to the management of brain metastases focus on individualizing patient care based on factors including the Karnofsky Performance Status, the tumor histology, the number of metastases, and the status of the systemic disease. A number of treatment approaches have been shown to be effective for brain metastases, including surgery; radiosurgery; whole-brain radiotherapy; and, more recently, chemotherapy. The use of adjuvant whole-brain radiotherapy with local therapies, such as surgery or radiosurgery, along with newer chemotherapy options, such as targeted biological agents, temozolomide, and implantable 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) Gliadel wafers, are at the forefront of recent advances in the treatment of patients with brain metastases that may provide longer survival and improved quality of life. Although there is no current standard treatment, some general guidelines are recommended for single metastases, oligometastases (two to three brain metastases), and multiple (four or more) brain metastases, and for new or recurrent disease. With advances in systemic therapy for cancer, the treatment of brain metastases is becoming an increasingly important determinant of the length of survival and quality of life for cancer patients.

Surgery versus radiosurgery for patients with a solitary brain metastasis from non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer is one of the leading causes of death in the developed countries. Patients die of local progression, disseminated disease or both. Brain metastases are often seen in non-small cell lung cancer patients and although they are frequently multiple, a subset of patients with a solitary brain metastasis (with controlled primary tumour) is regularly seen in clinical practice. Treatment of a solitary brain metastasis has usually been surgery, when possible, but the development of new stereotactic techniques of radiotherapy using a linear accelerator or the 'gamma knife' have provided new treatment options.

OBJECTIVES

To compare the effectiveness of surgery with that of radiosurgery, either combined with whole brain radiotherapy or administered alone, for patients with a solitary brain metastasis from successfully treated non-small cell lung cancer.

SEARCH STRATEGY

The following electronic databases were searched: the Cochrane Central Register of Controlled Trials (CENTRAL, 2004 issue 2), MEDLINE (1966 to present), EMBASE (1974 to present), CINAHL (1982 to present). Finally the Cochrane Lung Cancer Specialised Register was also searched.

SELECTION CRITERIA

Randomised and controlled trials that compared surgery (with or without whole brain irradiation) with all types of radiosurgery (with or without whole brain irradiation) for solitary brain metastasis from non-small cell lung cancer. All other types of studies i.e.prospective or retrospective cohort studies were not considered appropriate.Studies including patients with multiple brain metastasis or diagnosed without the support of CT scan/MRI diagnostic imaging were also excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the search results to identify suitable trials.

MAIN RESULTS

Despite extensive searching no randomised trials were found. Electronic search identified 686 references. A total of 47 were selected for further evaluation but none was relevant to this review.

AUTHORS' CONCLUSIONS

The reviewers felt that the inclusion of studies less rigorous than randomised trials would result in misleading findings. Cohort or single arm studies only provide partial information and have the risk of significant bias. From the evaluated studies, we found that a variety of different criteria were used for the definition of solitary brain metastasis. We observed that the term "single brain metastasis" was misused as synonymous with solitary brain metastasis. Some of the single arm or cohort studies come from single institutions where the availability of both techniques (radiosurgery and surgery) is not described. Therefore, a tendency to use the most accessible technique could be suspected. Finally, in order to determine which technique is superior for patients with a solitary brain metastasis from non-small cell lung cancer, an appropriate randomised trial should be designed. Based on the available evidence a meaningful conclusion cannot be drawn.

Long-term survivors after gamma knife radiosurgery for brain metastases

BACKGROUND

Stereotactic radiosurgery, with or without whole-brain radiation therapy, has become a valued management choice for patients with brain metastases, although their median survival remains limited. In patients who receive successful extracranial cancer care, patients who have controlled intracranial disease are living longer. The authors evaluated all brain metastasis in patients who lived for > or = 4 years after radiosurgery to determine clinical and treatment patterns potentially responsible for their outcome.

METHODS

Six hundred seventy-seven patients with brain metastases underwent 781 radiosurgery procedures between 1988 and 2000. Data from the entire series were reviewed; and, if patients had > or = 4 years of survival, then they were evaluated for information on brain and extracranial treatment, symptoms, imaging responses, need for further care, and management morbidity. These long-term survivors were compared with a cohort who lived for < 3 months after radiosurgery (n = 100 patients).

RESULTS

Forty-four patients (6.5%) survived for > 4 years after radiosurgery (mean, 69 mos with 16 patients still alive). The mean age at radiosurgery was 53 years (maximum age, 72 yrs), and the median Karnofsky performance score (KPS) was 90. The lung (n = 15 patients), breast (n = 9 patients), kidney (n = 7 patients), and skin (melanoma; n = 6 patients) were the most frequent primary sites. Two or more organ sites outside the brain were involved in 18 patients (41%), the primary tumor plus lymph nodes were involved in 10 patients (23%), only the primary tumor was involved in 9 patients (20%), and only brain disease was involved in 7 patients (16%), indicating that extended survival was possible even in patients with multiorgan disease. Serial imaging of 133 tumors showed that 99 tumors were smaller (74%), 22 tumors were unchanged (17%), and 12 tumors were larger (9%). Four patients had a permanent neurologic deficit after brain tumor management, and six patients underwent a resection after radiosurgery. Compared with the patients who had limited survival (< 3 mos), long-term survivors had a higher initial KPS (P = 0.01), fewer brain metastases (P = 0.04), and less extracranial disease (P < 0.00005).

CONCLUSIONS

Although the expected survival of patients with brain metastases may be limited, selected patients with effective intracranial and extracranial care for malignant disease can have prolonged, good-quality survival. The extent of extracranial disease at the time of radiosurgery was predictive of outcome, but this does not necessarily mean that patients cannot live for years if treatment is effective.

Radiosurgery for the treatment of spinal lung metastases

BACKGROUND

Spinal metastases are a common source of pain as well as neurologic deficit in patients with lung cancer. Metastases from lung cancer traditionally have been believed to be relatively responsive to radiation therapy. However, conventional external beam radiotherapy lacks the precision to allow delivery of large single-fraction doses of radiation and simultaneously limit the dose to radiosensitive structures such as the spinal cord. The current study evaluated the efficacy of single-fraction radiosurgery for the treatment of spinal lung cancer metastases.

METHODS

In the current prospective cohort evaluation, 87 lung cancer metastases to the spine in 77 patients were treated with a single-fraction radiosurgery technique with a follow-up period of 6 to 40 months (median, 12 months). The indication for radiosurgery treatment was pain in 73 cases, as a primary treatment modality in 7 cases, for radiographic tumor progression in 4 cases, and for progressive neurologic deficit in 3 cases.

RESULTS

Tumor volume ranged from 0.2 to 264 cm(3) (mean, 25.7 cm(3)). The maximum tumor dose was maintained at 15 to 25 grays (Gy) (mean, 20 Gy; median, 20 Gy). No radiation-induced toxicity occurred during the follow-up period. Long-term axial and radicular pain improvement occurred in 65 of 73 patients (89%) who were treated primarily for pain. Long-term radiographic tumor control was observed in all patients who underwent radiosurgery as their primary treatment modality or for radiographic tumor progression.

CONCLUSIONS

Spinal radiosurgery was found to be feasible, safe, and clinically effective for the treatment of spinal metastases from lung cancer. The results of the current study indicate the potential of radiosurgery in the treatment of patients with spinal lung metastases, especially those with solitary sites of spine involvement, to improve long-term palliation.

Brainstem Metastases: Management Using Gamma Knife Radiosurgery

OBJECTIVE:

Brainstem metastasis is an uncommon complication of systemic cancer, generally considered to have a highly unfavorable prognosis. Surgical risks are high and standard radiation or chemotherapy have little effect. The purpose of this study is to evaluate our experience using Gamma Knife radiosurgery (GKRS) for the management of brainstem metastasis.

METHODS:

Between July 1992 and March 2001, we treated 28 patients with brainstem metastasis using GKRS. Lesions were located in the pons in 17 patients, midbrain in nine, and medulla oblongata in two. At time of the radiosurgery, eight patients presented with another supratentorial metastasis. The most frequent primary tumor site was the lung (13 cases) followed by the melanoma in four cases, the kidney in two, and other locations in six. Only six patients underwent fractionated whole-brain radiation therapy. Mean marginal radiation dose for GKRS was 19.6 Gy (range, 11–30). Mean maximum diameter was 17.2 mm (range, 10–30).

RESULTS:

No GKRS-related morbidity was observed. Local tumor control was achieved in 92% of patients. Twenty-six patients have died. Death was related to the progression of the brainstem lesion in two cases. Mean and median survival after GKRS were 10.2 and 12 months, respectively. Follow-up periods in the two surviving patients were 12 and 13 months.

CONCLUSION:

The results of this small series demonstrate that GKRS can be a valuable modality for safe and effective management of brain stem metastasis. Owing to the high risk of surgical resection and low efficacy of medical treatment, radiosurgery can be proposed upfront.

Cerebral metastases pathology after radiosurgery

BACKGROUND

To the authors' knowledge, comprehensive human pathologic investigations that explore fundamental radiosurgical effects on metastatic brain tumors are sparse in the literature. The objective of this study was to analyze histopathologic findings in a set of clinically recurrent cerebral metastases after patients underwent stereotactic radiosurgery (SRS).

METHODS

In a series of 7500 patients who underwent radiosurgery, 2020 patients (27%) harbored cerebral metastases. Eighteen of 2020 patients (0.9%) underwent subsequent craniotomy for tumor removal anywhere from 1 month to 59 months after they received high-dose irradiation. Histologic and immunohistochemical investigations were performed on the surgically resected tissue specimens. These specimens were within the radiosurgical treatment volume of the metastatic tumor.

RESULTS

Light microscopy revealed 3 basic categories of histologic responses: acute-type, subacute-type, and chronic-type tissue reactions. A moderate-to-intense inflammatory cell reaction was seen in the tissue responses of well controlled neoplasms (i.e., in patients who had neoplasms that required craniotomy for recurrent disease > 5 months after SRS), whereas the inflammatory reaction was missing or sparse in poorly controlled neoplasms (patients who required craniotomy for recurrent disease < 5 months after SRS). This reaction was seen within the irradiated tumor volume and not in the peritumoral area nor in areas remote from the radiosurgical treatment volume. Immunohistochemical characterization demonstrated the presence of prominent CD68-positive macrophage and CD3-positive T-lymphocyte populations. A progressively severe vasculopathy also was observed with increasing time after radiosurgery.

CONCLUSIONS

Although causality has not been established, a brisk inflammatory response and more severe vasculopathy were observed in lesions in which recurrences were more delayed.

Linac stereotactic radiosurgery: An effective and safe treatment for elderly patients with brain metastases

PURPOSE

To evaluate the outcomes of radiosurgery for brain metastases in patients 65 years or older.

PATIENTS AND METHODS

Between January 1994 and January 2003, 117 patients (47 women, 70 men), median age 71 years (range, 65-86 years), received radiosurgery for 227 metastases. Sixty-one patients (55%) presented symptoms in relation to the brain metastases. Thirty-eight patients (32%) received whole-brain radiotherapy. Median metastasis diameter and volume were 21 mm (range, 0.5-75 mm) and 1.7 cc (range, 0.02-71 cc), respectively.

RESULTS

Median follow-up was 7 months (range, 1-45 months), 9.5 months for alive patients (range, 1-45 months). Median minimum and maximum doses were 14.5 Gy (6.5 Gy, 19.5 Gy), and 20.4 Gy (13.2 Gy, 41.9 Gy), respectively. Median survival was 8 months from the date of radiosurgery. Overall survival rates at 6 and 24 months were 58% +/- 5% and 13% +/- 4%, respectively. According to multivariate analysis, a low Karnofsky performance status was an independent unfavorable prognostic factor for overall survival (p = 0.003; odds ratio [OR] = 0.28; 95% confidence interval [CI], 0.14-0.56). Median brain disease-free survival was 10 months. Brain disease-free survival rates at 6 and 24 months were 67% +/- 6% and 40% +/- 7%, respectively. According to multivariate analysis, a radiosensitive lesion was an independent favorable factor (p = 0.038; OR = 0.42; 95% CI, 0.18-0.95); more than two metastases and a low Karnofsky performance status were independent unfavorable factors for brain disease-free survival (p = 0.046; OR = 2.15; 95% CI, 1.01-4.58 and p = 0.003; OR = 30.4; 95% CI, 3.1-296, respectively). Local control rates were 98% +/- 2% and 91% +/- 8.5% at 6 and 24 months. Out of the 61 patients presenting symptoms before radiosurgery, complete symptomatic response was achieved in 12 patients (20%), partial improvement in 25 (41%), stabilization in 7 (11%), and worsening in 4 (6%) related to a progression of the irradiated metastasis. Seven cases of radionecrosis were described and were related to the margin dose (p = 0.03).

CONCLUSION

Radiosurgery for elderly patients was effective and safe. Age alone should not be a criterion for denying radiosurgery to any patient with brain metastases.

Combination kyphoplasty and spinal radiosurgery: a new treatment paradigm for pathological fractures

OBJECT

Patients with symptomatic pathological compression fractures require spinal stabilization surgery for mechanical back pain control and irradiation for the underlying malignant process. The authors evaluated a treatment paradigm of closed fracture reduction and fixation involving kyphoplasty and subsequent spinal radiosurgery.

METHODS

Twenty-six patients (six men and 20 women, mean age 72 years) with pathological compression fractures (16 thoracic and 10 lumbar) were prospectively evaluated. Histological diagnoses included 11 lung, nine breast, four renal, one cholangiocarcioma, and one ocular melanoma. Seven lesions had received prior external-beam radiation therapy. All patients underwent kyphoplasty that involved the percutaneous transpedicular technique. Fiducial markers allowing for image guidance during CyberKnife treatment were placed, at time of the kyphoplasty, in the pedicles at adjacent levels. Patients underwent single-fraction radiosurgery (mean time after kyphoplasty 12 days) in an outpatient setting. The tumor dose was maintained at 16 to 20 Gy (mean 18 Gy) to the 80% isodose line. The treated tumor volume ranged from 12.7 to 37.1 cm3. No acute radiation-induced toxicity or new neurological deficit occurred during the follow-up period (range 11-24 months, median 16 months). Axial pain improved in 24 (92%) of 26 patients.

CONCLUSIONS

The combined kyphoplasty and spinal radiosurgery treatment paradigm was found to be clinically effective in patients with pathological fractures; there was no significant spinal canal compromise. In this technique two minimally invasive surgical procedures are combined to avoid the morbidity associated with open surgery while providing both immediate fracture fixation and administering a single-fraction tumoricidal radiation dose.

Use of the Radiation Therapy Oncology Group recursive partitioning analysis classification system and predictors of survival in 19 women with brain metastases from ovarian carcinoma

BACKGROUND

Brain metastases are an uncommon complication in women with primary ovarian carcinoma; thus, little is known about whether the Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis (RPA) prognostic classification system is valid in this patient population.

METHODS

From September 1985 to June 2002, 19 patients with brain metastases resulting from primary ovarian carcinoma underwent treatment at the Cleveland Clinic Foundation. The medical records of these patients were retrospectively reviewed.

RESULTS

At the time of data analysis, all 19 women had died. The median age at diagnosis of primary ovarian carcinoma and brain metastasis was 51 and 54 years of age, respectively. Fifteen patients presented with a Karnofsky performance status (KPS) of 70 or higher. Seven patients had a single brain lesion and 12 had multiple lesions. All RTOG RPA prognostic classes were represented, with median survivals of 24.7, 8.9, and 2.6 months for Classes I, II, and III, respectively (P = 0.31). Patients who underwent surgical resection survived longer than those who did not (33.7 vs. 7.4 mos). The presence of multiple lesions was adversely related to survival on multivariate analysis (P = 0.03). Primary control was an important predictor of survival on multivariate analysis as well (P = 0.01) and was achieved in 15 of the 19 women.

CONCLUSIONS

This is the first study to support the prognostic usefulness of the RTOG RPA classification for ovarian carcinoma patients with metastasis to the brain. The number of metastatic intracranial lesions should be included when determining the prognosis.

Single-fraction radiosurgery for the treatment of spinal breast metastases

BACKGROUND

The spine is the most common site of bony metastases in patients with osseous breast carcinoma metastases. Spine metastases are the source of significant pain and occasionally neurologic deficit in this patient population. Conventional external beam radiotherapy lacks the precision to allow delivery of large single-fraction doses of radiation and simultaneously limit the dose to radiosensitive structures such as the spinal cord. This study evaluated the clinical efficacy of the treatment of spinal breast carcinoma metastases with a single-fraction radiosurgical technique.

METHODS

In this prospective cohort evaluation, 68 breast carcinoma metastases to the spine in 50 patients were treated with a single-fraction radiosurgery technique with a follow-up period of 6-48 months, median 16 months. The most common indication for radiosurgery treatment was pain in 57 lesions, as a primary treatment modality in 8 patients, and for radiographic tumor progression, as a postsurgical boost, and for a progressive neurologic deficit in 1 patient each.

RESULTS

Tumor volume ranged from 0.8-197 cm3 (mean, 27.7 cm3). Maximum tumor dose was maintained at 15-22.5 Gy (mean, 19 Gy). No radiation-induced toxicity occurred during the follow-up period (6-48 mo). Long-term axial and radicular pain improvement occurred in 55 of 57 (96%) patients who were treated primarily for pain. Long-term radiographic tumor control was seen in all patients who underwent radiosurgery as their primary treatment modality, for radiographic tumor progression, or as a postsurgical treatment.

CONCLUSIONS

Spinal radiosurgery was found to be feasible, safe, and clinically effective for the treatment of spinal metastases from breast carcinoma. The results indicate the potential of radiosurgery in the treatment of patients with spinal breast metastases, especially those with solitary sites of spine involvement, to improve long-term palliation.

New frontiers in radiosurgery for the brain and body

Radiosurgery is defined as the use of highly focused beams of radiation to ablate a pathologic target, thus achieving a surgical objective by noninvasive means. Recent advances have allowed a wide variety of intracranial lesions to be effectively treated with radiosurgery, and radiosurgical treatment has been accepted as a standard part of the neurosurgical armamentarium. The advent of frameless radiosurgery now permits radiosurgical treatment to all parts of the body and is being actively explored by many centers. This article reviews some of the modern tools for radiosurgical treatment and discusses the current clinical practice of radiosurgery.

Radiosurgery in Metastatic Brain Cancer

Radiosurgery offers patients with brain metastases an effective and minimally invasive treatment modality. Radiosurgery provides local tumor control and prolongs survival in select patients with brain metastases. This review will discuss numerous aspects of radiosurgery, including the various delivery techniques and radiobiology. Treatment recommendations will be outlined in view of the available clinical data. Although surgery or radiosurgery with whole-brain radiotherapy remains an important option for patients with a solitary brain metastasis, radiosurgery with or without whole-brain radiotherapy should be considered in patients with a limited number of small tumors and a good prognosis.

Stereotactic radiosurgery for brain oligometastases: good for some, better for all?

Brain metastasis is the commonest central nervous system neoplasm affecting 25% patients with cancer. Recursive Partitioning Analysis (RPA) is a reliable prognostic index for patients with brain metastases. In patients with oligometastases and good performance status, decision-making regarding stereotactic radiosurgery (SRS) boost, following whole brain radiation therapy (WBRT), is guided by patient preference, access to radiosurgical facility and institutional policy. Published data for this review was identified by a systematic search of MEDLINE, CANCERLIT and EMBASE databases from 1990 until the present date and was restricted to the English language using appropriate search terms. All three identified randomized controlled trials consistently showed that radiosurgery improves intracranial local control (Level I evidence). Survival benefit, however, is limited to a selected subset of patients (RPA class 1) only. More importantly, patients receiving SRS have significantly better performance scores and decreased steroid requirements resulting in improved health-related quality-of-life (HRQoL). There is no head-to-head comparison of radiosurgery with neurosurgery in resectable single metastasis. SRS is associated with an improvement in outcome. A trial of radiosurgery versus neurosurgery should be attempted to define better the role of SRS in resectable single metastasis. Formal HRQoL assessments should be incorporated as primary end points in future prospective trials.

The American Society for Therapeutic Radiology and Oncology (ASTRO) evidence-based review of the role of radiosurgery for brain metastases

PURPOSE

To systematically review the evidence for the use of stereotactic radiosurgery in adult patients with brain metastases.

METHODS

Key clinical questions to be addressed in this evidence-based review were identified. Outcomes considered were overall survival, quality of life or symptom control, brain tumor control or response and toxicity. MEDLINE (1990-2004 June Week 2), CANCERLIT (1990-2003), CINAHL (1990-2004 June Week 2), EMBASE (1990-2004 Week 25), and the Cochrane library (2004 issue 2) databases were searched using OVID. In addition, the Physician Data Query clinical trials database, the proceedings of the American Society of Clinical Oncology (ASCO) (1997-2004), ASTRO (1997-2004), and the European Society of Therapeutic Radiology and Oncology (ESTRO) (1997-2003) were searched. Data from the literature search were reviewed and tabulated. This process included an assessment of the level of evidence.

RESULTS

For patients with newly diagnosed brain metastases, managed with whole-brain radiotherapy alone vs. whole-brain radiotherapy and radiosurgery boost, there were three randomized controlled trials, zero prospective studies, and seven retrospective series (which satisfied inclusion criteria). For patients with up to three (<4 cm) newly diagnosed brain metastases (and in one study up to four brain metastases), radiosurgery boost with whole-brain radiotherapy significantly improves local brain control rates as compared with whole-brain radiotherapy alone (Level I-III evidence). In one large randomized trial, survival benefit with whole-brain radiotherapy was observed in patients with single brain metastasis. In this trial, an overall increased ability to taper down on steroid dose and an improvement in Karnofsky performance status was seen in patients who were treated with radiosurgery boost as compared with patients treated with whole-brain radiotherapy alone. However, Level I evidence regarding overall quality of life outcomes using a validated instrument has not been reported. All randomized trials showed improved local control with the addition of radiosurgery to whole-brain radiotherapy. For patients with multiple brain metastases, there is no overall survival benefit with the use of radiosurgery boost to whole-brain radiotherapy (Level I-III evidence). Radiosurgery boost is associated with a small risk of early or late toxicity. In patients treated with radiosurgery alone (withholding whole-brain radiotherapy) as initial treatment, there were 2 randomized trials, 2 prospective cohort studies, and 16 retrospective series. There is Level I to Level III evidence that the use of radiosurgery alone does not alter survival as compared to the use of whole-brain radiotherapy. However, there is Level I to Level III evidence that omission of whole-brain radiotherapy results in poorer intracranial disease control, both local and distant (defined as remaining brain, outside the radiosurgery field). Quality of life outcomes have not been adequately reported. Radiosurgery is associated with a small risk of early or late toxicity. Radiosurgery as salvage for patients with brain metastases was reported in zero randomized trials, one prospective study, and seven retrospective series.

CONCLUSIONS

Based on Level I-III evidence, for selected patients with small (up to 4 cm) brain metastases (up to three in number and four in one randomized trial), the addition of radiosurgery boost to whole-brain radiotherapy improves brain control as compared with whole-brain radiotherapy alone. In patients with a single brain metastasis, radiosurgery boost with whole-brain radiotherapy improves survival. There is a small risk of toxicity associated with radiosurgery boost as compared with whole-brain radiotherapy alone. In selected patients treated with radiosurgery alone for newly diagnosed brain metastases, overall survival is not altered. However, local and distant brain control is significantly poorer with omission of upfront whole-brain radiotherapy (Level I-III evidence). Whether neurocognition or quality of life outcomes are different between initial radiosurgery alone vs. whole-brain radiotherapy (with or without radiosurgery boost) is unknown, because this has not been adequately tested. There was no statistically significant difference in overall toxicity between those treated with radiosurgery alone vs. whole-brain radiotherapy and radiosurgery boost based on an interim report from one randomized study. There is insufficient evidence as to the clinical benefit/risks radiosurgery used in the setting of recurrent or progressive brain metastases, although radiographic responses are well-documented.

Stereotactic interstitial radiosurgery for cerebral metastases

Object. The Photon Radiosurgery System (PRS) is a miniature x-ray generator that can stereotactically irradiate intracranial tumors by using low-energy photons. Treatment with the PRS typically occurs in conjunction with stereotactic biopsy, thereby providing diagnosis and treatment in one procedure. The authors review the treatment of patients with brain metastases with the aid of the PRS and discuss the indications, advantages, and limitations of this technique.

Methods. Clinical characteristics, treatment parameters, neuroimaging-confirmed outcome, and survival were reviewed in all patients with histologically verified brain metastases who were treated with the PRS at the Massachusetts General Hospital between December 1992 and November 2000. Local control of lesions was defined as either stabilization or diminution in the size of the treated tumor as confirmed by Gd-enhanced magnetic resonance imaging.

Between December 1992 and November 2000, 72 intracranial metastatic lesions in 60 patients were treated with the PRS. Primary tumors included lung (33 patients), melanoma (15 patients), renal cell (five patients), breast (two patients), esophageal (two patients), colon (one patient), and Merkle cell (one patient) cancers, and malignant fibrous histiocytoma (one patient). Supratentorial metastases were distributed throughout the cerebrum, with only one cerebellar metastasis. The lesions ranged in diameter from 6 to 40 mm and were treated with a minimal peripheral dose of 16 Gy (range 10–20 Gy). At the last follow-up examination (median 6 months), local disease control had been achieved in 48 (81%) of 59 tumors. An actuarial analysis demonstrated that the survival rates at 6 and 12 months were 63 and 34%, respectively. Patients with a single brain metastasis survived a mean of 11 months. Complications included four patients with postoperative seizures, three with symptomatic cerebral edema, two with hemorrhagic events, and three with symptomatic radiation necrosis requiring surgery.

Conclusions. Stereotactic interstitial radiosurgery performed using the PRS can obtain local control of cerebral metastases at rates that are comparable to those achieved through open resection and external stereotactic radiosurgery. The major advantage of using the PRS is that effective treatment can be accomplished at the time of stereotactic biopsy.

Surgery of brain metastases – Is there still a place for it?

The role of surgery in the treatment of metastatic brain tumors has always been a source of controversy. It was only in the early 1990s that two randomized prospective trials demonstrated that surgery plus radiation therapy improved survival in patients with single metastatic brain tumors vs. radiation therapy alone. This paper reviews these articles as well as other evidence outlining management options for multiple brain metastases. An attempt has been made to better define the role of surgery in brain metastases. The prognostic factors for brain metastases after surgery are also reviewed and the data comparing stereotactic radiosurgery to surgery is examined. A short description of surgical planning, operative techniques and tools, followed by a discussion on complication avoidance before, during, and after surgery is included.

Radiotherapy and chemotherapy of brain metastases

The authors have reviewed the results, the indications and the controversies regarding radiotherapy and chemotherapy of patients with newly diagnosed and recurrent brain metastases. Whole-brain radiotherapy, radiosurgery, hypofractionated stereotactic radiotherapy, brachytherapy and chemotherapy are the available options. New radiosensitizers and cytotoxic or cytostatic agents are being investigated. Adjuvant whole brain radiotherapy, either after surgery or radiosurgery, and prophylactic cranial irradiation in small-cell lung cancer are discussed, taking into account local control, survival, and risk of late neurotoxicity. Increasingly, the different treatments are tailored to the different prognostic subgroups, as defined by Radiation Therapy Oncology Group RPA Classes.

LINAC Radiosurgery as Single Treatment in Cerebral Metastases

OBJECTIVE

Stereotactic radiosurgery is a radiation technique of high radiation dose focused on a stereotactic intracranial target in a single fraction with high precision. LINAC Radiosurgery has gained increasing relevance in the treatment of brain metastases since it was introduced by Sturm (1987). METHOD AND PATIENT SELECTION: From January 1996 to August 2003 110 patients were treated with LINAC Radiosurgery. A combination of the University of Florida system and the X Knife System developed by Radionics was used in all patients. Seventy patients had a single and 40 patients multiple metastatic lesions at the time of diagnosis and treatment. Overall 161 intracerebral metastases were treated. Median tumor volume was 3.1 ccm (0.3-15 ccm). Median radiation dose to the tumor margin was 1830 cGy (range 1100-2200 cGy) prescribed to the 80% isodose line. Whole brain radiation therapy with a total dose of 30 Gy in 10 fractions was performed in 35 patients because of multiple metastases and LINAC Radiosurgery was used as boost for recurrences. In 75 patients LINAC Radiosurgery was used as single treatment.

RESULTS

The follow-up period was between 6 and 72 months. Local tumor control rate was 89.4%. Seventeen out of 161 metastases treated showed local recurrence. Eleven out of 75 patients treated with radiosurgery as single treatment developed distant recurrence and 3 out of 35 patients who were treated with whole brain radiation therapy (WBRT) and radiosurgery as boost. The 1-year survival rate is 54.9% with a median survival of 54 weeks.

CONCLUSION

LINAC Radiosurgery is an effective and safe treatment modality in patients with cerebral metastases located in any area of the brain. WBRT should be preserved for patients with multiple metastases or be delayed until multiple recurrence occurs. Surgery is still the treatment of choice in metastases with mass effect and surgical accessible location.

Lymphopenia: A new independent prognostic factor for survival in patients treated with whole brain radiotherapy for brain metastases from breast carcinoma

BACKGROUND AND PURPOSE

To determine overall survival (OS) and independent prognostic factors in patients with brain metastases (BM) from breast cancer treated by whole brain radiotherapy (WBR).

PATIENTS AND METHODS

One hundred and twenty (120) women with BM, treated in a single French cancer center between 02/91 and 06/01, were reviewed. BM were confirmed by computed tomography or magnetic resonance imaging. Survival time was defined as the time interval from the date of BM to the date of death or last follow-up. A Cox proportional hazards regression model was used to determine significant prognostic factors in a multivariate analysis.

RESULTS

Surgery was followed by WBR in 5 patients. One hundred and four (104) patients received exclusive WBR, eight received concomitant chemo-radiation, and one received chemo-radiation after surgery. The median survival time was 5 months (95% CI: 3-7 months). In the multivariate analysis, performance status over 1 and lymphopenia (<0.7 G/L) were found to be independent prognostic factors for poor survival. Based on the number of these independent prognostic factors, we propose a predictive model for survival in brain metastatic cancer patients. Median survival was 7 months for patients presenting none or one poor prognosis factor at diagnosis versus 2 months for patients with 2 poor prognosis factors (p<0.0001)

CONCLUSION

Brain metastases from breast cancer remain associated with very poor prognosis and there is a need for better treatment procedures. If confirmed in predictive models, the identification of prognostic subgroups, based on KPS and lymphopenia, among patients with BM from breast cancer would help physicians select patients for future clinical trials.

The impact of whole-brain radiation therapy on the long-term control and morbidity of patients surviving more than one year after gamma knife radiosurgery for brain metastases

PURPOSE

To better analyze how whole-brain radiotherapy (WBXRT) affects long-term tumor control and toxicity from the initial stereotactic radiosurgery (SRS) for brain metastases, we studied these outcomes in patients who had survived at least 1 year from SRS.

METHODS AND MATERIALS

We evaluated the results of gamma knife radiosurgery for 160 brain metastases in 110 patients who were followed for a median of 18 months (range, 12-122 months) after SRS. Eighty-two patients had a solitary brain metastasis and 28 patients had multiple metastases. Seventy patients (116 tumors) were treated with initial radiosurgery and WBXRT, whereas 40 patients (44 lesions) initially received radiosurgery alone. Median treatment volume was 1.9 cc in the entire group, 2.3 cc in the WBXRT group, and 1.6 cc in the SRS alone group. Median tumor dose was 16 Gy (range, 12-21 Gy).

RESULTS

At 1, 3, and 5 years, local tumor control was 84.1% +/- 5.5%, 68.6% +/- 8.7%, and 68.6% +/- 8.7% with SRS alone compared with 93.1% +/- 2.4%, 87.7% +/- 4.9%, and 65.7% +/- 10.2%. with concurrent WBXRT and SRS (p = 0.0228, univariate). We found that WBXRT improved local control in patient subsets tumor volume > or =2 cc, peripheral dose < or =16 Gy, single metastases, nonradioresistant tumors, and lung cancer metastases (p = 0.0069, 0.0080, 0.0083, 0.0184, and 0.0348). Distal intracranial failure developed at 1, 3, and 5 years in 26.0% +/- 7.1%, 74.5% +/- 9.4%, and 74.5% +/- 9.4% with SRS alone compared with 20.7% +/- 4.9%, 49.0% +/- 8.7%, and 61.8% +/- 12.8% with concurrent WBXRT and SRS (p = 0.0657). We found a trend for improved distal intracranial control with WBXRT for only nonradioresistant tumors (p = 0.054). Postradiosurgery complications developed in 2.8% +/- 1.2% and 10.7% +/- 3.5% at 1 and 3-5 years and was unaffected by WBXRT (p = 0.7721). WBXRT did not improve survival in the entire series (p = 0.5027) or in any subsets.

CONCLUSIONS

In this retrospective study of 1-year survivors of SRS for brain metastases, the addition of concurrent WBXRT to SRS was associated with an improved local control rate in patient subsets with tumor volume > or =2 cc, peripheral dose < or =16 Gy, single metastases, nonradioresistant tumors, and specifically lung cancer metastases. A trend was noted for improved distal intracranial control for patients having nonradioresistant tumors. Distant intracranial relapse >1 year posttreatment is a significant problem with or without initial WBXRT.

The oligometastatic state in breast cancer: hypothesis or reality

The term 'oligometastasis' was initially used to describe a restricted locoregional tumour load, but the term has now become synonymous with isolated distant metastases. The existence of an oligometastatic state is still not widely recognised in the management of breast cancer patients. However, there are a number of patients who do develop isolated metastases and in whom long term survival can be achieved following appropriately targeted treatment. This review article discusses the possible biological mechanisms behind the development of an oligometastatic state and the findings from different trials which describe results following radical therapy for isolated metastatic disease. Although no large scale trials in this area have yet been undertaken, there is evidence to support the existence of an oligometastatic state in patients with breast cancer and we discuss the appropriate management for this clinical scenario.

Brain Metastases in Patients with Breast Cancer: New Horizons

Brain metastases occur in as many as one third of patients with disseminated breast cancer. In this article, we discuss various presentations of brain metastases from breast cancer and review evidence that supports different treatment options. Because no prospective, randomized, controlled studies, to our knowledge, have focused solely on patients with brain metastases from breast cancer, we will first review retrospective studies of patients with brain metastases from breast cancer. Randomized studies of patients with brain metastases caused by multiple primary cancers will also be examined, and the conclusions from these studies will be extrapolated to patients with breast cancer. Because brain metastases from breast cancer occur in a variety of different clinical settings, ranging from a single metastasis without extensive extracranial disease to multiple brain metastases with widespread extracranial disease, treatment approaches must be tailored to the specific circumstances of each patient. For different clinical scenarios, neurosurgical resection, radiosurgery, and/or whole-brain radiation therapy may be appropriate treatment options. For patients with brain metastases from breast cancer that overexpresses HER2/neu, trastuzumab could alter the natural history of the non-central nervous system (CNS) disease. Therefore, HER2 status could also influence the treatment of brain metastases from breast cancer. Given the prevalence of brain metastases in patients with metastatic breast cancer in contemporary series, the rationale for clinical trials of CNS screening and prophylactic cranial irradiation will be discussed.

Therapeutic management of brain metastasis

This review focuses on the management of brain metastases. The four main modes of therapy are discussed: whole brain radiation therapy (WBRT), surgery, radiosurgery, and chemotherapy. Young patients with limited extracranial disease may benefit from surgical resection of a single brain metastasis, and from radiosurgery (or stereotactic radiotherapy) if two to four brain metastases are present. Whether WBRT after surgery or radiosurgery is beneficial is uncertain. Therefore, two approaches can be justified in patients with a good prognosis: WBRT after surgery or radiosurgery, or alternatively, observation with MRI follow-up after surgery or radiosurgery. A hyperfractionated radiation scheme is then to be preferred to limit late toxicity of WBRT. Patients with extensive extracranial tumour activity or impaired quality of life may benefit from radiosurgery (one to four brain metastases), or from shorter WBRT schedules. We propose a decision tree on the various ways to treat brain metastasis.

Initial clinical experience with frameless radiosurgery for patients with intracranial metastases

PURPOSE

To review the initial clinical experience with frameless stereotactic radiosurgery (SRS) for treating intracranial metastatic disease.

METHODS AND MATERIALS

Sixty-four patients received frameless SRS for intracranial metastatic disease. Minimum follow-up was 6 months with none lost to follow-up. Patients had a median of 2 metastases and a maximum of 4. The median number of isocenters was 2 with median arcs of 10 and median dose of 17.5 Gy. Thirteen patients were treated for progressive/recurrent disease after surgical resection or whole brain radiotherapy (WBRT). Fifty-one patients were treated with frameless SRS as an an adjunct to initial treatment. Of the total treated, 17 were treated with SRS alone, 20 were treated with WBRT plus SRS, 16 were treated with surgical resection plus SRS, and the remaining 11 were treated with surgical resection plus WBRT plus SRS.

RESULTS

With a median actuarial follow-up period of 8.2 months, ultimate local control was 88%. The median time to progression was 8.1 months. The median overall survival was 8.7 months. Of the 17 patients treated with SRS alone, 86% had ultimate local control with mean overall survival of 7.1 months. Of the 13 patients who received surgical resection plus SRS without WBRT as primary treatment, there was 85% ultimate local control with an overall survival of 10.3 months. Three patients treated with initial surgery alone had recurrence treated with SRS 2-3 months after resection. All these patients obtained local control and median survival was >10 months. Of the 13 patients who received WBRT followed by SRS as boost treatment, 92% had local control and mean overall survival was 7.3 months. Of 7 patients who received SRS after recurrence after WBRT, 100% had local control with median survival of 8.2 months. For 8 patients who received surgery followed by WBRT and SRS, local control was 50%; however, ultimate intracranial control was achieved in 7 of 8 patients with repeat SRS and surgical resection. The overall survival in this group of patients was 14.7 months. No patient had a serious (Grade 3 or higher) complication requiring intervention.

CONCLUSIONS

Frameless optically guided radiosurgery is less invasive, can be performed as a standard radiotherapy-based simulation procedure, and maintains submillimetric accuracy. Our initial results with frameless SRS for metastatic disease suggest survival times and local control (88%) eqiuvalent to frame-based methodologies. Practical noninvasive delivery makes treatment and potential retreatment to avoid WBRT more feasible.

Hypofractionated conformal stereotactic radiotherapy alone or in combination with whole-brain radiotherapy in patients with cerebral metastases

PURPOSE

The aim was to evaluate treatment of cerebral metastases with hypofractionated conformal stereotactic radiotherapy (HCSRT) or whole-brain radiotherapy (WBRT) in combination with a stereotactic boost.

METHODS AND MATERIALS

Forty-seven patients were treated with HCSRT and 14 patients with WBRT in combination with a stereotactic boost. Radiation doses were 40 Gy (5 fractions) in HCSRT or 30 Gy (WBRT) combined with a mean dose of 17 Gy stereotactically (1-3 fractions).

RESULTS

The median survival time in the HCSRT as well as the WBRT group was 5.0 months, and 87% died of extracranial disease. Radiologic follow-up (mean, 3.7 months after treatment) showed local control in the HCSRT group in 84% and in the WBRT group in 100%. Patients treated with HCSRT developed new brain metastases distant from the irradiated area in 25%. Two patients treated with HCSRT deteriorated neurologically during treatment, and in 2 patients radionecrosis developed.

CONCLUSIONS

Although there may be a higher risk of distant new metastases, HCSRT as a treatment for brain metastases seems to be as effective as WBRT in combination with a stereotactic boost. Complications are in the range of what has been reported previously.

Treatment of brain metastases in renal cell carcinoma: radiotherapy, radiosurgery, or surgery?

Metastases from renal cell carcinoma raise specific therapeutic problems because they are relatively unresponsive to whole brain radiation therapy and tend to bleed. Recently, stereotactically guided high-precision irradiation as a single dose application (radiosurgery) showed promising treatment results for selected patients with brain metastases from renal cell carcinoma. Radiosurgery appears attractive due to its low risk and minimal invasiveness. Multiple lesions can be treated at the same time and retreatments can be performed for local or distant recurrences.

Combination kyphoplasty and spinal radiosurgery: a new treatment paradigm for pathological fractures

OBJECT

Patients with symptomatic pathological compression fractures require a stabilization procedure for mechanical control of back pain as well as radiation therapy for the underlying malignant process. In this study the authors evaluated a treatment paradigm of closed fracture reduction and fixation in which kyphoplasty was used, followed by single-fraction spinal radiosurgery performed with the CyberKnife.

METHODS

Twenty-six patients (six men and 20 women, mean age 72 years) with histologically confirmed pathological compression fractures (16 thoracic, 10 lumbar) were prospectively evaluated. For inclusion in the study, the patients' presenting symptoms were limited to pain without neurological deficits. Histological findings included 11 lung, nine breast, and four renal carcinomas, one cholangiocarcinoma, and one ocular melanoma. All patients underwent kyphoplasty of the affected vertebral body, for which a percutaneous transpedicular procedure was used. Fiducial markers that allow image guidance for CyberKnife radiosurgery were placed into the pedicles at the adjacent levels at the time of the kyphoplasty procedure. Patients then underwent single-fraction radiosurgery (at a mean of 12 days after kyphoplasty) in an outpatient setting. The tumor dose was maintained at 16 to 20 Gy to the 80% isodose line (mean 18 Gy). Treated tumor volume ranged from 12.7 to 37.1 cm3. Axial pain improved in 24 (92%) of 26 patients during the follow-up period of 7 to 20 months.

CONCLUSIONS

A combined kyphoplasty and spinal radiosurgery treatment paradigm was found to be safe and clinically effective for patients with pathological fractures without significant spinal canal compromise. This technique combines two minimally invasive surgical procedures, thereby avoiding the morbidity associated with open surgery while providing immediate fracture fixation as well as a single-fraction tumoricidal radiation dose.

Linac radiosurgery as a tool in neurosurgery

Stereotactic radiosurgery is a radiation technique that uses a high radiation dose focused on a stereotactic defined intracranial target in single fraction with high precision. In the 1980s, linear accelerators were introduced as a tool for radiosurgery beneath the already accepted gamma unit. Technique and mechanical precision of LINACs have become equal to the gamma unit and LINAC radiosurgery became more and more used recently. From January 1996 to August 2003 we have treated 237 patients with LINAC radiosurgery. A combination of the University of Florida system and the X Knife System, developed by Radionics, was used in all patients. A number of 110 patients had 161 brain metastases treated, whereas the local tumor control rate was 89.4%. The 1-year survival rate was 54.9% with a median survival of 54 weeks. In 55 patients we have treated 57 meningiomas, mostly located at the skull base (37 out of 55 patients). Local tumor control rate in our patients with skull base meningiomas at 5-year follow up was 97.2%. In this time period, we have also treated acoustic schwannoma, glioma, pituitary adenoma, arteriovenous malformations and patients with trigeminal neuralgia. LINAC radiosurgery has become a daily tool in neurosurgery and changed treatment strategies especially in the treatment of brain metastases and skull base meningiomas towards a less aggressive and multimodality approach. It is not only an alternative to open surgery, but also a very effective adjuvant treatment modality in many neuro-oncological patients, which helps us to enhance tumor control rate, minimize morbidity and increase postoperative quality of life.

Gamma Knife radiosurgery for intracranial metastatic melanoma: an analysis of survival and prognostic factors

Objective of this study was to evaluate retrospectively the effectiveness of Gamma Knife radiosurgery for intracranial metastatic melanoma and to identify prognostic factors related to survival. Twenty-six patients with intracranial metastases (72 lesions) from melanoma underwent Gamma Knife radiosurgery. In 14 patients (54%) whole-brain radiotherapy (WBRT) was performed as part of the initial treatment, and in 12 patients (38%) immunotherapy and/or chemotherapy was given after Gamma Knife radiosurgery. The median tumor volume for Gamma Knife radiosurgery treated lesions was 1.72 cm3. The median prescribed radiation dose was 18 Gy (range 8-22 Gy) typically prescribed to the isodose at the tumor margin. Univariate and multivariate analyses were used to determine significant prognostic factors affecting survival. Overall median survival was 6 months after Gamma Knife radiosurgery, and 1-year survival was 25%. The median survival from the onset of brain metastases was 9 months and from the original diagnosis of melanoma was 50 months (range 4-160 months). There were no major acute or late GKS complications. In univariate testing, the Karnofsky score equal to or higher than 90% (P < 0.01, log-rank test), supratentorial localization (P < 0.001, log-rank test), intracranial tumor volume less than 1 cm3 (P < 0.02, log-rank test), and absence of neurological signs or symptoms before Gamma Knife radiosurgery (P < 0.003, log-rank test) were significant favorable factors for survival. In multivariate regression analyses, the most important predictors associated with increased survival were a KPS > or = 90 (P < 0.023), female sex (P < 0.004), supratentorial localization (P < 0.01), and absence of neurological symptoms (P < 0.008). Radiosurgery is a noninvasive, safe, and effective treatment option for patients with single or multiple intracranial metastases from melanoma. Female sex, Karnofsky score > or = 90, supratentorial localization and lack of symptoms before the Gamma Knife radiosurgery were good independent predictors of survival.

Resection of brain metastases previously treated with stereotactic radiosurgery

Object. To date, no report has been published on outcomes of patients undergoing resection for brain metastases who were previously treated with stereotactic radiosurgery (SRS). Consequently, the authors reviewed their institutional experience with this clinical scenario to assess the efficacy of surgical intervention.

Methods. Sixty-one patients (each harboring three or fewer brain lesions), who were treated at a single institution between June 1993 and August 2002 were identified. Patient charts and their neuroimaging and pathological reports were retrospectively reviewed to determine overall survival rates, surgical complications, and recurrence rates.

A univariate analysis revealed that patient preoperative recursive partitioning analysis (RPA) classification, primary disease status, preoperative Karnofsky Performance Scale score, type of focal treatment undergone for nonindex lesions, and major postoperative surgical complications were factors that significantly affected survival (p ≤ 0.05). In contrast, only the RPA class and focal (conventional surgery or SRS) treatment of nonindex lesions significantly (or nearly significantly) affected survival in the multivariate analysis. Major neurological complications occurred in only 2% of patients. The median time to distant recurrence after resection was 8.4 months; that to local recurrence was not reached. The overall median survival time was 11.1 months, with 25% of patients surviving 2 or more years. Conventional surgery facilitated tapering of steroid administration.

Conclusions. The complication, morbidity, survival, and recurrence rates are consistent with those seen after conventional surgery for recurrent brain metastases. Our results indicate that in selected patients with a favorable RPA class in whom nonindex lesions are treated with focal modalities, surgery can provide long-term control of SRS-treated lesions and positively affect overall survival.

Does gamma knife surgery stimulate cellular immune response to metastatic brain tumors? A histopathological and immunohistochemical study

Object. The aim of this study was to analyze the cellular immune response and histopathological changes in secondary brain tumors after gamma knife surgery (GKS).

Methods. Two hundred ten patients with cerebral metastases underwent GKS. Seven patients underwent subsequent craniotomy for tumor removal between 1 and 33 months after GKS. Four of these patients had one tumor, two patients had two tumors, and one patient had three. Histological and immunohistochemical investigations were performed. In addition to routine H & E and Mallory trichrome staining, immunohistochemical reactions were conducted to characterize the phenotypic nature of the cell population contributing to the tissue immune response to neoplastic deposits after radiosurgery.

Light microscopy revealed an intensive lymphocytic infiltration in the parenchyma and stroma of tumor samples obtained in patients in whom surgery was performed over 6 months after GKS. Contrary to this, extensive areas of tissue necrosis with either an absent or scanty lymphoid population were observed in the poorly controlled neoplastic specimens obtained in cases in which surgery was undertaken in patients less than 6 months after GKS. Immunohistochemical characterization demonstrated the predominance of CD3-positive T cells in the lymphoid infiltration.

Conclusions. Histopathological findings of the present study are consistent with a cellular immune response of natural killer cells against metastatic brain tumors, presumably stimulated by the ionizing energy of focused radiation.

Does gamma knife surgery stimulate cellular immune response to metastatic brain tumors? A histopathological and immunohistochemical study

Object.The aim of this study was to analyze the cellular immune response and histopathological changes in secondary brain tumors after gamma knife surgery (GKS).

Methods.Two hundred ten patients with cerebral metastases underwent GKS. Seven patients underwent subsequent craniotomy for tumor removal between 1 and 33 months after GKS. Four of these patients had one tumor, two patients had two tumors, and one patient had three. Histological and immunohistochemical investigations were performed. In addition to routine H & E and Mallory trichrome staining, immunohistochemical reactions were conducted to characterize the phenotypic nature of the cell population contributing to the tissue immune response to neoplastic deposits after radiosurgery.

Light microscopy revealed an intensive lymphocytic infiltration in the parenchyma and stroma of tumor samples obtained in patients in whom surgery was performed over 6 months after GKS. Contrary to this, extensive areas of tissue necrosis with either an absent or scanty lymphoid population were observed in the poorly controlled neoplastic specimens obtained in cases in which surgery was undertaken in patients less than 6 months after GKS. Immunohistochemical characterization demonstrated the predominance of CD3-positive T cells in the lymphoid infiltration.

Conclusions.Histopathological findings of the present study are consistent with a cellular immune response of natural killer cells against metastatic brain tumors, presumably stimulated by the ionizing energy of focused radiation.

Stereotactic radiosurgery for patients with solid brain metastases: current status

The goal of this article is to provide a contemporary update on the use of stereotactic radiosurgery (SRS) for the treatment of intracranial metastatic disease. We discuss the rationale for employing SRS in brain metastases and describe the critical factors that predict outcome. We highlight the main clinical indications for SRS including treatment of recurrent brain metastases after previous whole brain radiation therapy (WBRT), as a boost after WBRT, and as sole therapy for newly diagnosed tumors. For each clinical scenario, we offer a treatment algorithm based on our clinical experience. The article also addresses the most common complications associated with SRS and their treatment.

The pathogenesis and treatment of brain metastases: a comprehensive review

Brain metastases are the most common intracranial tumors and their incidence is increasing. Untreated brain metastases are associated with a poor prognosis and a poor performance status. The role of surgery in the management of multiple brain metastases is still controversial. As more than 70% of patients have multiple metastases at the time of diagnosis, whole brain radiotherapy is the treatment of choice in most cases. Brain metastases are an ideal target for stereotactic radiosurgery, as they are better circumscribed than primary brain tumors. Currently, chemotherapy has a limited role in the treatment of most brain metastases. Several new therapies, with a good penetration through the blood brain barrier, such as temozolomide, have been used in brain metastases with different results depending on the histology of the primary tumor. A better understanding of the complex processes underlying the development of brain metastasis will enable us to develop more satisfactory targeted treatments.

18F-FDG and11C-methionine PET for evaluation of treatment response of lung cancer after stereotactic radiotherapy

This study was performed to investigate the feasibility of FDG- and L-[methyl-11C]methionine (Met)-PET for the follow up of lung cancer after stereotactic radiotherapy (SRT). Nine patients (pt) with solitary lung cancer underwent SRT. Met- and FDG-PET studies were performed one week before SRT and from one week to 8 months after SRT. Responses to SRT were complete in 2 pt and partial in 7 pt. Met- and FDG-PET scan showed high tracer uptake in all tumors before SRT. After SRT, standardized uptake values (SUV) of FDG and Met changed concordantly. Both decreased with time in 5 pt but did not decrease steadily in 4 pt, where 2 pt showed an increase at 1 to 2 weeks after SRT and 2 pt showed an increase at more than 3 months after SRT. The former appears to reflect the acute reaction to SRT and the latter radiation-induced pneumonitis. Although the addition of Met-PET did not provide additional information over FDG-PET, FDG- and Met-PET could be used to evaluate the treatment effect of SRT.

Management of brain metastases

Patients with brain metastases have a generally poor outcome with a median survival after diagnosis of approximately 4 months. Management of brain metastases involves symptomatic treatment and definitive therapy, with the goal of stabilizing and improving neurologic function and survival. Traditional and novel therapies, including whole-brain radiation therapy (WBRT), surgery, radiosurgery, radiosensitizers, and chemotherapy are reviewed. The results of important clinical trials are discussed. In addition, current controversies in the management of brain metastases, such as the choice of surgery or radiosurgery for resectable lesions and the possible avoidance of (WBRT), are highlighted.

Linear Accelerator Radiosurgery in the Treatment of Brain Metastases

OBJECTIVE:

To review a 12-year experience treating metastatic brain disease with linear accelerator-based stereotactic radiosurgery (SRS).

METHODS:

We performed a retrospective analysis of all patients treated between 1989 and 2001 with linear accelerator radiosurgery for brain metastases. Patients were followed up both clinically and with imaging studies to document local control, regional control, and survival. Demographic data, dosing parameters, number of lesions, histology, history of whole-brain radiation therapy, and other factors were obtained prospectively. Cox proportional-hazards regression with multivariate and univariate analysis was performed with Stata 8.0 software.

RESULTS:

A total of 383 patients received SRS for brain metastases during the study interval. Median survival was 9 months. Patients with tumor-type melanoma or multiple metastatic lesions had decreased survival. Actuarial 1-year local control was 75%. Differences in regional control rates were not statistically significant between patients treated with SRS and whole-brain radiation therapy versus SRS alone.

CONCLUSION:

Radiosurgery is an effective and safe method for treating selected patients with brain metastases.

Cyberknife radiosurgery for metastatic spine tumors

Metastatic spine tumors affect a large number of patients each year, resulting in significant pain,destruction of the spinal column causing mechanical instability, and neurologic deficits. Standard therapeutic options include surgery and fractionated external beam radiotherapy. The first option can be associated with significant morbidity and limited local tumor control. Conversely, radiotherapy may provide less than optimal pain relief and tumor control, because the total dose is limited by the tolerance of adjacent tissues, such as the spinal cord. The emerging technique of spinal radiosurgery represents a logical extension of the current state-of-the-art radiation therapy. It has the potential to significantly improve local control of cancer of the spine, which could translate into more effective palliation and potentially longer survival. Spinal radiosurgery might offer improved pain control and a longer duration of pain control by giving larger radiobiologic doses.This technique also allows for the treatment of lesions previously irradiated using external beam radiation. Another advantage to the patient is that irradiation can be completed in a single day rather than several weeks, which is not inconsequential for patients with a limited life expectancy. In addition, cancer patients may have difficulty with access to a radiation treatment facility for prolonged daily fractionated therapy. This technique allows for the treatment of lesions previously irradiated using external beam radiation.Finally, the procedure is minimally invasive compared with open surgical techniques and can be performed in an outpatient setting. Similar to intracranial radiosurgery, stereo-tactic radiosurgery now has a feasible and safe delivery system available for the treatment of spinal metastatic lesions. The major potential benefit of radiosurgical ablation of spinal lesions is a relatively short treatment time in an outpatient setting combined with potentially better local control of the tumor with minimal risk of side effects. CyberKnife spinal radiosurgery offers a new and important alternative therapeutic modality for the treatment of spinal metastases in medically inoperable patients, previously irradiated sites, and for lesions not amenable to open surgical techniques or as an adjunct to surgery. Spinal radiosurgery is likely to become an essential part of any neurosurgical spine center that treats a large number of patients with spinal metastases.

Management of brain metastases

Solid tumour brain metastases are a frequent clinical dilemma for oncologists and general physicians. The sound management of brain metastases requires a multidisciplinary approach. In this review we discuss the diagnosis and management of brain metastases including the role of surgery, radiotherapy, and chemotherapy. The standard approaches of surgical excision and primary radiotherapy have evolved from randomised studies. However, controversies remain regarding post-surgery irradiation in the setting of a solitary metastasis and the role of palliative chemotherapy.