Stereotactic radiosurgical treatment of brain metastases

Molecular Biology of Brain Metastases

Brain metastases (BMs) often occur in patients with lung cancer, breast cancer, and melanoma and are the leading cause of morbidity and mortality. The incidence of BM has increased with advanced neuroimaging and prolonged overall survival of cancer patients. With the advancement of local treatment modalities, including stereotactic radiosurgery and navigation-guided microsurgery, BM can be controlled long-term, even in cases with multiple lesions. However, radiation/chemotherapeutic agents are also toxic to the brain, usually irreversibly and cumulatively, and it remains difficult to completely cure BM. Thus, we must understand the molecular events that begin and sustain BM to develop effective targeted therapies and tools to prevent local and distant treatment failure. BM most often spreads hematogenously, and the blood-brain barrier (BBB) presents the first hurdle for disseminated tumor cells (DTCs) entering the brain parenchyma. Nevertheless, how the DTCs cross the BBB and settle on relatively infertile central nervous system tissue remains unknown. Even after successfully taking up residence in the brain, the unique tumor microenvironment is marked by restricted aerobic glycolysis metabolism and limited lymphocyte infiltration. Brain organotropism, certain phenotype of primary cancers that favors brain metastasis, may result from somatic mutation or epigenetic modulation. Recent studies revealed that exosome secretion from primary cancer or over-expression of proteolytic enzymes can "pre-condition" brain vasculoendothelial cells. The concept of the "metastatic niche," where resident DTCs remain dormant and protected from systemic chemotherapy and antigen exposure before proliferation, is supported by clinical observation of BM in patients clearing systemic cancer and experimental evidence of the interaction between cancer cells and tumor-infiltrating lymphocytes. This review examines extant research on the metastatic cascade of BM through the molecular events that create and sustain BM to reveal clues that can assist the development of effective targeted therapies that treat established BMs and prevent BM recurrence.

Pre-operative Stereotactic Radiosurgery for Cerebral Metastatic Disease: A Retrospective Dose-Volume Study

BACKGROUND AND PURPOSE

Stereotactic radiosurgery (SRS) after maximal safe resection is an accepted treatment strategy for patients with cerebral metastatic disease. Despite its high conformality profile, the incidence of radionecrosis (RN) remains high. SRS delivered pre-operatively could be associated with a reduced incidence of RN. We sought to evaluate whether neoadjuvant SRS could reduce radiotherapy doses in a cohort of patients treated with post-operative SRS.

METHODS

A cohort of 47 brain metastases (BM) treated at 2 academic institutions was retrospectively analyzed. Subjects underwent surgical extirpation of BMs and subsequent SRS to surgical bed. Post-operative volumetric and dosimetric data was collected from records or recreations of delivered plans; pre-operative data were derived from hypothetical radiotherapy courses and compared using Wilcoxon signed-rank tests.

RESULTS

Higher planned tumor volume post-operatively (median[IQR] 12.28 [6.54, 18.69]cc vs. 10.20 [4.53, 21.70]cc respectively, p=0.4150) was observed. The median prescribed radiotherapy dose (DRx) was 16Gy pre-operatively and 24Gy post-operatively(p<0.0001). Further investigations revealed improved pre-operative conformity index (1.23[1.20, 1.29] vs. 1.29[1.23, 1.39], p=0.0098) and gradient index (2.72[2.59, 2.98] vs. 2.94[2.69, 3.47], p=0.0004). A significant difference was found in normal brain tissue exposed to 10Gy (12.97[6.78, 25.54]cc vs. 32.13[19.42, 48.40]cc, p<0.0001), 12Gy (9.31[4.56, 17.43]cc vs. 23.80[14.74, 36.56]cc, p<0.0001), and 14Gy (5.62[3.23, 11.61]cc vs. 17.47[9.00, 28.31]cc, p<0.0001), favoring pre-operative SRS.

CONCLUSIONS

Neoadjuvant SRS is associated reduced DRx, better conformality profile and decreased radiation to normal tissue. These findings could support the use of neoadjuvant SRS for the treatment of BMs.

Clinical Experience of Bevacizumab for Radiation Necrosis in Patients with Brain Metastasis

Background

As the application of radiotherapy to brain metastasis (BM) increases, the incidence of radiation necrosis (RN) as a late toxicity of radiotherapy also increases. However, no specific treatment for RN is indicated except long-term steroids. Here, we summarize the clinical results of bevacizumab (BEV) for RN.

Methods

Ten patients with RN who were treated with BEV monotherapy (7 mg/kg) were retrospectively reviewed. RN diagnosis was made using MRI with or without perfusion MRI. Radiological response was based on Response Assessment in Neuro-Oncology criteria for BM. The initial response was observed after 2 cycles every 2 weeks, and maintenance observed after 3 cycles every 3–6 weeks of increasing length intervals.

Results

The initial response of gadolinium (Gd) enhancement diameter maintained stable disease (SD) in 9 patients, and 1 patient showed partial response (PR). The initial fluid-attenuated inversion recovery (FLAIR) response showed PR in 4 patients and SD in 6 patients. The best radiological response was observed in 9 patients. Gd enhancement response was 6 PR and 3 SD between 15–43 weeks. Reduction of FLAIR showed PR in 5 patients and SD in 4 patients. Clinical improvement was observed in all but 1 patient. Five patients were maintained on protocol with durable response up to 23 cycles. However, 2 patients stopped treatment due to primary cancer progression, 1 patient received surgical removal from tumor recurrence, and 1 patient changed to systemic chemotherapy for new BM. Grade 3 intractable hypertension occurred in 1 patient who had already received antihypertensive medication.

Conclusion

BEV treatment for RN from BM radiotherapy resulted in favorable radiological (60%) and clinical responses (90%). Side effects were expectable and controllable. We anticipate prospective clinical trials to verify the effect of BEV monotherapy for RN.

Two-staged stereotactic radiosurgery for the treatment of large brain metastases: Single institution experience and review of literature

Introduction: Two-staged stereotactic radiosurgery (SRS) has been shown as an effective treatment for brain metastases that are too large for single fraction SRS. Methods: Patients with large brain metastases (>4 cm³) treated with two-staged SRS from January 2017 to December 2019 at our institution were retrospectively identified. Results: There were 23 brain metastases treated. The normal brain volume receiving equivalent 12Gy-in-single-fraction was defined as V_12E. The V_12E for original single-fraction GKS plan (mean of 41.4 cm³, range 5.6-146.1 cm³) was significantly higher compared to that of the second stage (mean of 23.7 cm³, range 2.8-92.7 cm³). The median tumor volume measured at the second stage (4.30 cm³) was reduced by an average of 52.2% compared to the first stage (9.58 cm³). Three patients (27.3%) showed local tumor progression in 4 tumors (20%). The median time to progression was 152 days. Conclusions: Two-staged SRS is an effective treatment technique for large brain metastasis that results in significant reduction of tumor volume at the second stage SRS. Optimal treatment dose has not yet been defined.

Results of Whole Brain Radiation Therapy in Patients with Brain Metastases from Colorectal Carcinoma

Aims and background

Carcinoma of the colon-rectum is an infrequent cause of brain metastases, constituting 1-5% of all metastatic lesions to the brain. We reviewed our experience in the treatment of brain metastases from colorectal cancer to define the efficacy of whole brain radiation therapy as a palliative measure in this setting of patients.

Methods

Twenty-three consecutive cases of brain metastasis from colorectal cancer treated between 1999 and 2004 were identified in the files of the Division of Radiotherapy of the A Businco Regional Oncological Hospital, Cagliari. Their records were reviewed for patient and tumor characteristics and categorized according to the RTOG RPA classes.

Results

Fifteen patients (65%) had multiple metastases. Twenty-one patients (91%) showed extracranial metastases. Fourteen patients were classified as RTOG RPA class II and 9 class III. The median radiation dose delivered was 2000 cGy in 5 fractions in one week (range, 20-36 Gy). In 14 of 20 assessable patients (70%), symptomatic improvement was observed. The median follow-up and survival time for all the patients, 12 females and 11 males, was 3 months. In 3 patients only the cause of death was the brain metastasis.

Conclusions

Despite the disappointing survival time, external radiation therapy to the whole brain proved to be an efficacious palliative treatment for patients with multiple or inoperable brain metastasis from colorectal cancer.

Clinical features of brain metastases from hepatocellular carcinoma using gamma knife surgery

Background

Brain metastases from hepatocellular carcinoma (HCC) are rare, but their incidence is increasing because of developments in recent therapeutic advances. The purpose of this study was to investigate the characteristics of brain metastases from HCC, to evaluate the predictive factors, and to assess the efficacy of gamma knife surgery (GKS).

Method

A retrospective study was performed on patients with brain metastases from HCC who were treated at Tokyo Gamma Unit Center from 2005 to 2014.

Results

Nineteen patients were identified. The median age at diagnosis of brain metastases was 67.0 years. Fifteen patients were male and four patients were female. Six patients were infected with hepatitis B virus (HBV). Two patients were infected with hepatitis C virus (HCV). Eleven patients were not infected with HBV or HCV. The median interval from the diagnosis of HCC to brain metastases was 32.0 months. The median number of brain metastases was two. The median Karnofsky performance score at first GKS was 70. The median survival time following brain metastases was 21.0 weeks. Six-month and 1-year survival rates were 41.2 and 0%, respectively. One month after GKS, no tumor showed progressive disease. The HBV infection (positive vs. negative) was significantly associated with survival according to univariate analysis (p = 0.002).

Conclusions

The patients having brain metastases from HCC had poor prognosis and low performance state. Therefore, GKS is an acceptable option for controlling brain metastases from HCC because GKS is noninvasive remedy and local control is reasonable.

Single Brain Metastases from Kidney Tumors. Clinico-Pathologic Considerations on a Series of 29 Cases

Twenty-nine cases of single cerebral metastases from renal carcinoma were the object of a retrospective and prospective study covering a period of 15 years (1975–1988). The best diagnostic means were NMR imaging with paramagnetic contrast medium and CAT scans after intravenous injection of a double dose of contrast medium. All patients underwent total surgical removal of the cerebral lesion. Radiotherapy was useful but had less influence on further reproduction than in metastases from tumors of other sites. The median survival was 28.1 months in patients who received radiotherapy and 23 months in the others. No significant difference in survival was found between the group of patients with unknown primary tumors and the other group with diagnosed primary neoplastic disease.

Brain Metastases from Endometrial Carcinoma: Report of Three Cases and Review of the Literature

Aims and background

Endometrial carcinoma is a rare cause of brain metastases, accounting for less than 1% of all metastatic lesions to the brain. This report aims to review our experience in the treatment of patients with brain metastases from endometrial carcinoma in order to establish the characteristics of these patients and evaluate the results and efficacy of whole-brain radiation therapy as a palliative measure.

Methods

Three cases of brain metastases from endometrial carcinoma treated with radiotherapy were identified in the files of the Division of Radiotherapy at the A. Businco Regional Oncological Hospital of Cagliari between 1999 and 2005.

Results

All patients had brain metastases as the only sign of systemic disease (a single lesion in 2 patients and 2 lesions in 1 patient). Two patients were classified as RTOG RPA class I and 1 patient as class III. Radiotherapy to the brain was delivered after surgical resection in the first 2 patients and as the only method of palliation in the third patient. The delivered radiation dose was 3000 cGy in 10 fractions over 2 weeks in the postoperative setting and 2000 cGy in 5 fractions over 1 week to the patient treated with irradiation alone. The 2 surgically treated patients are alive and well after 16 and 64 months, respectively. The patient treated with palliative intent died 2 months after irradiation.

Conclusions

The combination of surgery and postoperative whole-brain irradiation in selected patients with solitary brain metastases from endometrial carcinoma is an effective method of palliation.

Radiosurgical Treatment Verification Using Removable Megavoltage Radiation Detectors

Introduction

Accurate dose delivery is critical to the success of stereotactic radiosurgery. Unfortunately, verification of the accuracy of treatment delivery remains a challenging problem. Existing radiosurgery delivery paradigms are limited in their ability to verify the accurate delivery of radiation beams using data sampled from the beam after it has traversed the patient. The Zap-X Radiosurgery System (Zap Surgical Systems, San Carlos, CA) addresses this issue by implementing a fully integrated treatment delivery system that utilizes a factory commissioned megavoltage (MV) imager to measure the transmitted beam. The measured intensity is then compared with an expected value in order to confirm that treatment is proceeding as expected. The purpose of this study was to evaluate a prototype system and investigate the accuracy of an attenuation model used in generating the expected transmitted intensity values.

Methods

A prototype MV imager was used to measure transmitted beam intensities at various exposure levels and through several thicknesses of solid water. The data were used to evaluate imager linearity and model accuracy.

Results

Experimental results indicate that a quadratic attenuation model is appropriate for predicting beam attenuation and that the imager exhibits excellent dose linearity.

Conclusions

The MV imager system is shown to be capable of accurately acquiring the data needed to confirm treatment validity.

Do Recent Advances in MR Technologies Contribute to Better Gamma Knife Radiosurgery Treatment Results for Brain Metastases?

The detection of intracerebral lesions has improved greatly with advancements in MR imaging, especially the greater sensitivity of the 1.5 Tesla unit versus the older 1.0 Tesla unit. We aimed to determine whether improvements in MR imaging have actually improved diagnostic capabilities and treatment outcomes in gamma knife radiosurgery (GKRS) for brain metastases (METs). Ours was a retrospective study of a consecutive series of 1179 patients (441 females, 738 males, mean age: 63 years, range: 19–92 years) with brain METs who underwent GKRS from 1998 to 2004. Our treatment policy was to irradiate all lesions visible on MR images during a single GKRS session. Mean and median tumor numbers were seven and three (range; 1–74). The 1179 patients were divided into two groups: a 1.0 T-group of 660 patients examined using a 1.0 Tesla MR unit before August, 2002, and a 1.5 T-group of 519 examined using a 1.5 Tesla MR unit after September 2002. In the 1.5 T-group, lesion volumes as small as 0.004 cc were detected with a 5 mm slice thickness. The corresponding lesion size was 0.013 cc in the 1.0 T-group. One or more lesions invisible on a 5 mm slice study were additionally detected on a 2 mm slice study in 47.8% of patients in the 1.0 T-group and 25.2% in the 1.5 T-group (p<.0001). The median survival time (MST) in the 1.5 T-group was significantly longer than that in the 1.0 T-group (8.4 vs. 6.3 months, p=.0004). Due to biases in patient numbers between the two groups, we analyzed subgroups with KPS of 80% or better, no neurological deficits, stable primary tumors, lung cancer, tumor numbers of four or less and tumor volumes of 10.0 cc or smaller. In every subgroup analysis, the MSTs of the 1.5-Tesla group were significantly longer than those of the 1.0-Tesla group. The prognosis of a cancer patient is undoubtedly influenced by multiple factors. Nevertheless, we conclude that application of the 1.5 Tesla MR unit has had a favorable impact on diagnosis and GKRS treatment results in patients with brain METs.

Control of brain metastases from radioresistant tumors treated by stereotactic radiosurgery

Renal cell carcinoma, sarcoma, and melanoma are considered to be "radioresistant" tumor histologies. Brain metastases (BM) from these tumors are considered unlikely to be controlled using the relatively low doses used in whole brain radiotherapy (WBRT). Our objective was to analyze the efficacy of stereotactic radiosurgery (SRS) on local control and overall survival of BM from radioresistant primary tumors. We reviewed all patients who received Gamma Knife Radiosurgery (GKRS) for BM at Columbia University Medical Center between January 2009 and April 2014. All patients were treated using the Gamma Knife Perfexion System. Dosimetric data was collected from treatment plans and metastases were categorized as radioresistant or not. Response was assessed by reviewing follow-up brain imaging studies and classified according to RECIST. Local control and median overall survival were calculated using the Kaplan-Meier method. In total, 373 tumors were analyzed from 126 patients. Of these tumors, 49 (13.1 %) originated from radioresistant cancers. The overall local control rate in the radioresistant cohort was 89.8 and 90.1 % in the non-radioresistant cohort. Univariate and multivariate analyses demonstrated that radioresistance status of the primary tumor had no statistically significant effect on local control with hazard ratios of 1.0 (p = 1.0, 95 % CI 0.388-2.576) and 0.954 (p = 0.926, 95 % CI 0.349-2.603) respectively. Median overall survival for both radioresistant and non-radioresistant cohorts was 20.0 months, with a p value of 0.926. There was no significant difference in local control of BM from radioresistant and non-radioresistant primary tumors treated with GKRS. Both cohorts showed excellent response and local control, suggesting that SRS upfront or in addition to WBRT may be an appropriate strategy in the treatment of BM from radioresistant cancers. Median overall survival for both cohorts was equal, suggesting that improved local control may be associated with an improvement in long-term survival.

Hypofractionated radiosurgery has a better safety profile than single fraction radiosurgery for large resected brain metastases

The purpose of this study is to compare the safety and efficacy of single fraction radiosurgery (SFR) with hypofractionated radiosurgery (HR) for the adjuvant treatment of large, surgically resected brain metastases. Seventy-five patients with 76 resection cavities ≥ 3 cm received 15 Gray (Gy) × 1 SFR (n = 40) or 5-8 Gy × 3-5 HR (n = 36). Cumulative incidence of local failure (LF) and radiation necrosis (RN) was estimated accounting for death as a competing risk and compared with Gray's test. The effect of multiple covariates was evaluated with the Fine-Gray proportional hazards model. The most common HR dose-fractionation schedules were 6 Gy × 5 (44%), 7-8 Gy × 3 (36%), and 6 Gy × 4 (8%). The median follow-up was 11 months (range 2-71). HR patients had larger median resection cavity volumes (24.0 vs. 13.3 cc, p < 0.001), planning target volumes (PTV) (37.7 vs. 20.5 cc, p < 0.001), and cavity to PTV expansion margins (2 vs. 1.5 mm, p = 0.002) than SFR patients. Cumulative incidence of LF (95% CI) at 6 and 12-months for HR versus SFR was 18.9% (0.07-0.34) versus 15.9% (0.06-0.29), and 25.6% (0.12-0.42) versus 27.2% (0.14-0.42), p = 0.80. Cumulative incidence of RN (95% CI) at 6 and 12 months for HR vs. SFR was 3.3% (0.00-0.15) versus 10.7% (0.03-0.23), and 10.3% (0.02-0.25) versus 19.2% (0.08-0.34), p = 0.28. On multivariable analysis, SFR was significantly associated with an increased risk of RN, with a HR of 3.81 (95% CI 1.04-13.93, p = 0.043). Hypofractionated radiosurgery may be the more favorable treatment approach for radiosurgery of cavities 3-4 cm in size and greater.

Platinum sensitivity and CD133 expression as risk and prognostic predictors of central nervous system metastases in patients with epithelial ovarian cancer

Background

To characterize prognostic and risk factors of central nervous system (CNS) metastases in patients with epithelial ovarian cancer (EOC).

Methods

A retrospective analysis of Xijing Hospital electronic medical records was conducted to identify patients with pathologically confirmed EOC and CNS metastases. In addition to patient demographics, tumor pathology, treatment regimens, and clinical outcomes, we compared putative cancer stem cell marker CD133 expression patterns in primary and metastatic lesions as well as in recurrent EOC with and without CNS metastases.

Results

Among 1366 patients with EOC, metastatic CNS lesions were present in 29 (2.1%) cases. CD133 expression in primary tumor was the only independent risk factor for CNS metastases; whilst the extent of surgical resection of primary EOC and platinum resistance were two independent factors significantly associated with time to CNS metastases. Absence of CD133 expression in primary tumors was significantly associated with high platinum sensitivity in both patient groups with and without CNS metastases. Platinum resistance and CD133 cluster formation in CNS metastases were associated with decreased survival, while multimodal therapy including stereotactic radiosurgery (SRS) for CNS metastases was associated with increased survival following the diagnosis of CNS metastases.

Conclusions

These data suggest that there exist a positive association between CD133 expression in primary EOC, platinum resistance and the increased risk of CNS metastases, as well as a less favorable prognosis of EOC. The absence of CD133 clusters and use of multimodal therapy including SRS could improve the outcome of metastatic lesions. Further investigation is warranted to elucidate the true nature of the association between platinum sensitivity, CD133 expression, and the risk and prognosis of CNS metastases from EOC.

Stereotactic radiosurgery (SRS) for brain metastases: a systematic review

In many patients with brain metastases, the primary therapeutic aim is symptom palliation and maintenance of neurologic function, but in a subgroup, long-term survival is possible. Local control in the brain, and absent or controlled extracranial sites of disease are prerequisites for favorable survival. Stereotactic radiosurgery (SRS) is a focal, highly precise treatment option with a long track record. Its clinical development and implementation by several pioneering institutions eventually rendered possible cooperative group randomized trials. A systematic review of those studies and other landmark studies was undertaken. Most clinicians are aware of the potential benefits of SRS such as a short treatment time, a high probability of treated-lesion control and, when adhering to typical dose/volume recommendations, a low normal tissue complication probability. However, SRS as sole first-line treatment carries a risk of failure in non-treated brain regions, which has resulted in controversy around when to add whole-brain radiotherapy (WBRT). SRS might also be prescribed as salvage treatment in patients relapsing despite previous SRS and/or WBRT. An optimal balance between intracranial control and side effects requires continued research efforts.

Stereotactic radiosurgery for treatment of brain metastases. A report of the DEGRO Working Group on Stereotactic Radiotherapy

BACKGROUND

This report from the Working Group on Stereotaktische Radiotherapie of the German Society of Radiation Oncology (Deutsche Gesellschaft für Radioonkologie, DEGRO) provides recommendations for the use of stereotactic radiosurgery (SRS) on patients with brain metastases. It considers existing international guidelines and details them where appropriate.

RESULTS AND DISCUSSION

The main recommendations are: Patients with solid tumors except germ cell tumors and small-cell lung cancer with a life expectancy of more than 3 months suffering from a single brain metastasis of less than 3 cm in diameter should be considered for SRS. Especially when metastases are not amenable to surgery, are located in the brain stem, and have no mass effect, SRS should be offered to the patient. For multiple (two to four) metastases--all less than 2.5 cm in diameter--in patients with a life expectancy of more than 3 months, SRS should be used rather than whole-brain radiotherapy (WBRT). Adjuvant WBRT after SRS for both single and multiple (two to four) metastases increases local control and reduces the frequency of distant brain metastases, but does not prolong survival when compared with SRS and salvage treatment. As WBRT carries the risk of inducing neurocognitive damage, it seems reasonable to withhold WBRT for as long as possible.

CONCLUSION

A single (marginal) dose of 20 Gy is a reasonable choice that balances the effect on the treated lesion (local control, partial remission) against the risk of late side effects (radionecrosis). Higher doses (22-25 Gy) may be used for smaller (< 1 cm) lesions, while a dose reduction to 18 Gy may be necessary for lesions greater than 2.5-3 cm. As the infiltration zone of the brain metastases is usually small, the GTV-CTV (gross tumor volume-clinical target volume) margin should be in the range of 0-1 mm. The CTV-PTV (planning target volume) margin depends on the treatment technique and should lie in the range of 0-2 mm. Distant brain recurrences fulfilling the aforementioned criteria can be treated with SRS irrespective of previous WBRT.

Metastases to the brain: current management perspectives

Brain metastases are ten-times more common than primary brain tumors and are a common complication in patients with systemic cancer. The most common sources of brain metastases are lung and breast cancers, although in 15% of patients, the primary site is unknown. Optimal treatment is dependant upon tumor location, size, number of tumors and status of the systemic disease. Currently, management of brain metastases with surgery, radiotherapy and stereotactic radiosurgery is known to improve the quality of life and even life expectancy for selected patients. Techniques under investigation include focal radiation techniques, magnetic resonance imaging guided thermal ablation of metastases, drug delivery modes that bypass the blood-brain barrier and novel drug and molecular therapeutics. Efforts are ongoing to understand the molecular biology of brain metastases.

Radiation-induced apoptosis of oligodendrocytes in the adult rat optic chiasm

OBJECTIVES

The present study characterized glial cell injury provoked in adult rat chiasm within 24 hours after a single, high-dose irradiation of 20 Gy.

METHODS

All chiasmal glial cells in a section were counted, and the percentage of TUNEL-positive glial cells exhibiting apoptotic morphology was defined as the apoptotic rate.

RESULTS

Numbers of apoptotic cells increased significantly (p<0.0001) from 3 to 8 hours after exposure, but returned to baseline levels by 24 hours. Little evidence of apoptosis was observed in non-irradiated chiasms. Similar patterns of increase in apoptotic rate were observed in the genu of the corpus callosum, but the extent was significantly lower (p=0.047) in the optic chiasm, with a maximal rate of 1.9%. Immunohistochemically, apoptotic cells were positive for CNP, a marker for oligodendrocytes.

DISCUSSION

These data indicate that chiasmal irradiation induces limited, but significant apoptotic depletion of the oligodendroglial population, and may participate in the development of radiation-induced optic neuropathy.

Hypofractionated radiosurgery for intact or resected brain metastases: defining the optimal dose and fractionation

Background

Hypofractionated Radiosurgery (HR) is a therapeutic option for delivering partial brain radiotherapy (RT) to large brain metastases or resection cavities otherwise not amenable to single fraction radiosurgery (SRS). The use, safety and efficacy of HR for brain metastases is not well characterized and the optimal RT dose-fractionation schedule is undefined.

Methods

Forty-two patients treated with HR in 3-5 fractions for 20 (48%) intact and 22 (52%) resected brain metastases with a median maximum dimension of 3.9 cm (0.8-6.4 cm) between May 2008 and August 2011 were reviewed. Twenty-two patients (52%) had received prior radiation therapy. Local (LC), intracranial progression free survival (PFS) and overall survival (OS) are reported and analyzed for relationship to multiple RT variables through Cox-regression analysis.

Results

The most common dose-fractionation schedules were 21 Gy in 3 fractions (67%), 24 Gy in 4 fractions (14%) and 30 Gy in 5 fractions (12%). After a median follow-up time of 15 months (range 2-41), local failure occurred in 13 patients (29%) and was a first site of failure in 6 patients (14%). Kaplan-Meier estimates of 1 year LC, intracranial PFS, and OS are: 61% (95% CI 0.53 – 0.70), 55% (95% CI 0.47 – 0.63), and 73% (95% CI 0.65 – 0.79), respectively. Local tumor control was negatively associated with PTV volume (p = 0.007) and was a significant predictor of OS (HR 0.57, 95% CI 0.33 - 0.98, p = 0.04). Symptomatic radiation necrosis occurred in 3 patients (7%).

Conclusions

HR is well tolerated in both new and recurrent, previously irradiated intact or resected brain metastases. Local control is negatively associated with PTV volume and a significant predictor of overall survival, suggesting a need for dose escalation when using HR for large intracranial lesions.

Predictors of survival in contemporary practice after initial radiosurgery for brain metastases

PURPOSE

The number of brain metastases (BM) is a major consideration in determining patient eligibility for stereotactic radiosurgery (SRS), but the evidence for this popular practice is equivocal. The purpose of this study was to determine whether, following multivariate adjustment, the number and volume of BM held prognostic significance in a cohort of patients initially treated with SRS alone.

METHODS AND MATERIALS

A total of 251 patients with primary malignancies, including non-small cell lung cancer (34%), melanoma (30%), and breast carcinoma (16%), underwent SRS for initial treatment of BM. SRS was used as the sole management (62% of patients) or was combined with salvage treatment with SRS (22%), whole-brain radiation therapy (WBRT; 13%), or resection (3%). Median follow-up time was 9.4 months. Survival was determined using the Kaplan-Meier method. Cox regression was used to assess the effects of patient factors on distant brain failure (DBF), local control (LC), and overall survival (OS).

RESULTS

LC at 1 year was 94.6%, and median time to DBF was 10 months. Median OS was 11.1 months. On multivariate analysis, statistically significant predictors of OS were presence of extracranial disease (hazard ratio [HR], 4.2, P<.001), total tumor volume greater than 2 cm(3) (HR, 1.98; P<.001), age ≥60 years (HR, 1.67; P=.002), and diagnosis-specific graded prognostic assessment (HR, 0.71; P<.001). The presence of extracranial disease was a statistically significant predictor of DBF (HR, 2.15), and tumor volume was predictive of LC (HR, 4.56 for total volume >2 cm(3)). The number of BM was not predictive of DBF, LC, or OS.

CONCLUSIONS

The number of BM is not a strong predictor for clinical outcomes following initial SRS for newly diagnosed BM. Other factors including total treatment volume and systemic disease status are better determinants of outcome and may facilitate appropriate use of SRS or WBRT.

Validation of Recursive Partitioning Analysis and Diagnosis-Specific Graded Prognostic Assessment in patients treated initially with radiosurgery alone

OBJECT

Brain metastases present a therapeutic challenge because patients with metastatic cancers live longer now than in the recent past due to systemic therapies that, while effective, may not penetrate the blood-brain barrier. In the present study the authors sought to validate the Diagnosis-Specific Graded Prognostic Assessment (DS-GPA), a new prognostic index that takes into account the histological characteristics of the primary tumor, and the Radiation Therapy Ontology Group Recursive Partitioning Analysis (RPA) system by using a single-institution database of patients who were treated initially with stereotactic radiosurgery (SRS) alone for brain metastases.

METHODS

Investigators retrospectively identified adult patients who had undergone SRS at a single institution, MD Anderson Cancer Center, for initial treatment of brain metastases between 2003 and 2010 but excluded those who had undergone craniotomy and/or whole-brain radiation therapy at an earlier time; the final number was 251. The Leksell Gamma Knife was used to treat 223 patients, and a linear accelerator was used to treat 28 patients. The patient population was grouped according to DS-GPA scores as follows: 0-0.5 (7 patients), 1 (33 patients), 1.5 (25 patients), 2 (63 patients), 2.5 (14 patients), 3 (68 patients), and 3.5-4 (41 patients). The same patients were also grouped according to RPA classes: 1 (24 patients), 2 (216 patients), and 3 (11 patients). The most common histological diagnoses were non-small cell lung cancer (34%), melanoma (29%), and breast carcinoma (16%). The median number of lesions was 2 (range 1-9) and the median total tumor volume was 0.9 cm(3) (range 0.3-22.9 cm(3)). The median radiation dose was 20 Gy (range 14-24 Gy). Stereotactic radiosurgery was performed as the sole treatment (62% of patients) or combined with a salvage treatment consisting of SRS (22%), whole-brain radiation therapy (12%), or resection (4%). The median duration of follow-up was 9.4 months.

RESULTS

In this patient group the median overall survival was 11.1 months. The DS-GPA prognostic index divided patients into prognostically significant groups. Median survival times were 2.8 months for DS-GPA Scores 0-0.5, 3.9 months for Score 1, 6.6 months for Score 1.5, 12.9 months for Score 2, 11.9 months for Score 2.5, 12.2 months for Score 3, and 31.4 months for Scores 3.5-4 (p < 0.0001). In the RPA groups, the median overall survival times were 38.8 months for Class 1, 9.4 months for Class 2, and 2.8 months for Class 3 (p < 0.0001). Neither the RPA class nor the DS-GPA score was prognostic for local tumor control or new lesion-free survival. A multivariate analysis revealed that patient age > 60 years, Karnofsky Performance Scale score ≤ 80%, and total lesion volume > 2 cm(3) were significant adverse prognostic factors for overall survival.

CONCLUSIONS

Application of the DS-GPA to a database of patients with brain metastases who were treated with SRS appears to be valid and offers additional prognostic refinement over that provided by the RPA. The DS-GPA may also allow for improved selection of patients to undergo initial SRS alone and should be studied further.

Prognostic factors for patients in postoperative brain metastases from surgically resected non-small cell lung cancer

BACKGROUND

Postoperative recurrence in non-small cell lung cancer (NSCLC) reduces the life expectancy of patients. In this retrospective study, we investigated the prognostic factors in patients with postoperative brain metastases from surgical resected non-small cell lung cancer (NSCLC).

METHODS

We conducted a retrospective chart review of patients who had undergone resection for NSCLC between April 2004 and February 2009 and found 65 had experienced postoperative brain metastases by March 2010. We reviewed these patients for clinicopathological information, treatments and responses to treatment, and overall survival.

RESULTS

The 5-year survival rate after the diagnosis of brain metastases was 15.4 %. Significantly favorable prognostic factors for patients after a diagnosis of brain metastases included female gender, adenocarcinoma, a small number (1-3) of brain metastases, no extracranial metastasis at the diagnosis of brain metastases, radiation treatment (whole-brain radiation and/or stereotactic irradiation), and local treatment [stereotactic irradiation and/or surgical operation (craniotomy)]. Furthermore, in patients with only brain metastases as the postoperative initial recurrence, the favorable positive prognostic factors included a small number (1-3) of brain metastases, adjuvant chemotherapy, chemotherapy (including adjuvant and other chemotherapy and excluding epidermal growth factor receptor-tyrosine kinase inhibitors), and local treatment.

CONCLUSIONS

Our study found that the foregoing clinical characteristics in postoperative brain metastases and the administration of treatment contributed to patient life expectancy.

Brain metastases research 1990-2010: pattern of citation and systematic review of highly cited articles

BACKGROUND

High and continuously increasing research activity related to different aspects of prevention, prediction, diagnosis and treatment of brain metastases has been performed between 1990 and 2010. One of the major databases contains 2695 scientific articles that were published during this time period. Different measures of impact, visibility, and quality of published research are available, each with its own pros and cons. For this overview, article citation rate was chosen.

RESULTS

Among the 10 most cited articles, 7 reported on randomized clinical trials. Nine covered surgical or radiosurgical approaches and the remaining one a widely adopted prognostic score. Overall, 30 randomized clinical trials were published between 1990 and 2010, including those with phase II design and excluding duplicate publications, for example, after longer followup or with focus on secondary endpoints. Twenty of these randomized clinical trials were published before 2008. Their median number of citations was 110, range 13-1013, compared to 5-6 citations for all types of publications. Annual citation rate appeared to gradually increase during the first 2-3 years after publication before reaching high levels.

CONCLUSIONS

A large variety of preclinical and clinical topics achieved high numbers of citations. However, areas such as quality of life, side effects, and end-of-life care were underrepresented. Efforts to increase their visibility might be warranted.

Gamma knife surgery for brain metastases from ovarian cancer

Background

Brain metastases from ovarian cancer are rare, but their incidence is increasing. The purpose of this study was to investigate the characteristics of brain metastases from ovarian cancer, and to assess the efficacy of treatment with gamma knife surgery (GKS).

Methods

A retrospective review was performed of patients with brain metastases from ovarian cancer who were treated at the Tokyo Gamma Unit Center from 2006 to 2010.

Results

Sixteen patients were identified. Their median age at diagnosis of brain metastases was 56.5 years, the median interval from diagnosis of ovarian cancer to brain metastases was 27.5 months, and the median number of brain metastases was 2. The median Karnofsky Performance Score (KPS) at the first GKS was 80. The median survival following diagnosis of brain metastases was 12.5 months, and 6-month and 1-year survival rates were 75 % and 50 %, respectively. The tumor control rate was 86.4 %. The KPS (<80 vs ≥80) and total volume of brain metastases (<10 cm³ vs ≥10 cm³) were significantly associated with survival according to a univariate analysis (p = 0.004 and p = 0.02, respectively).

Conclusions

The results of this study suggest that GKS is an effective remedy and acceptable choice for the control of brain metastases from ovarian cancer.

A prospective pilot study of two-session Gamma Knife surgery for large metastatic brain tumors

The purpose of this prospective study is to evaluate the efficacy and limitations of two-session Gamma Knife radiosurgery (GKS) alone for large metastatic brain tumors. Inclusion criteria were as follows: (i) patients with large metastatic brain tumors (volume >15 cm(3) in the supratentorial region or >10 cm(3) in the infratentorial region), and (ii) tumors not causing clinical signs of impending cerebral herniation. Twenty-eight lesions in 27 consecutive patients (18 men and 9 women, age range 32 to 88 years, median age 65 years) were included in this study. The radiosurgical protocol was as follows: 20-30 Gy given in two fractions 3-4 weeks apart. The local tumor control rate and the overall survival rate were calculated by using the Kaplan-Meier method. Median tumor volumes were 17.8 cm(3) at first GKS and 9.7 cm(3) at second GKS. Median follow-up time was 8.9 months. The local control rate was 85 % at 6 months and 61 % at 12 months. The overall survival rate after GKS was 63 % at 6 months and 45 % at 12 months. The 1-year rate of prevention of neurological death was maintained at 78 %. Mean Karnofsky performance status (KPS) improved from 61 [95 % confidence interval (CI), 57-71] at first GKS to 80 (95 % CI, 74-85) at second GKS; the best follow-up mean KPS was 85 (95 % CI, 78-91) (p < 0.001). Local tumor recurrence necessitated craniotomy in two patients and repeat GKS in three patients. Seventeen patients died, and the causes of death were as follows: 3 from local progression, 2 from meningeal carcinomatosis, and 12 from progression of the primary tumor. Delayed symptomatic perilesional edema developed in one patient and eventually resolved with conservative treatment. Two-session GKS for large brain metastases appears to be an effective treatment in terms of both local tumor control and neurological palliation with minimal treatment-related morbidity. These data suggest that two-session GKS could be used as an alternative to surgical resection of large tumors in patients with significant comorbidity and/or at an advanced age. The optimum regimen for dose and fraction schedule remains to be established.

Gamma knife radiosurgery for brainstem metastasis

OBJECTIVE

Brainstem metastases are rarely operable and generally unresponsive to conventional radiation therapy or chemotherapy. Recently, Gamma Knife Radiosurgery (GKRS) was used as feasible treatment option for brainstem metastasis. The present study evaluated our experience of brainstem metastasis which was treated with GKRS.

METHODS

Between November 1992 and June 2010, 32 patients (23 men and 9 women, mean age 56.1 years, range 39-73) were treated with GKRS for brainstem metastases. There were metastatic lesions in pons in 23, the midbrain in 6, and the medulla oblongata in 3 patients, respectively. The primary tumor site was lung in 21, breast in 3, kidney in 2 and other locations in 6 patients. The mean tumor volume was 1,517 mm(3) (range, 9-6,000), and the mean marginal dose was 15.9 Gy (range, 6-23). Magnetic Resonance Imaging (MRI) was obtained every 2-3 months following GKRS. Follow-up MRI was possible in 24 patients at a mean follow-up duration of 12.0 months (range, 1-45). Kaplan-Meier survival analysis was used to evaluate the prognostic factors.

RESULTS

Follow-up MRI showed tumor disappearance in 6, tumor shrinkage in 14, no change in tumor size in 1, and tumor growth in 3 patients, which translated into a local tumor control rate of 87.5% (21 of 24 tumors). The mean progression free survival was 12.2 months (range, 2-45) after GKRS. Nine patients were alive at the completion of the study, and the overall mean survival time after GKRS was 7.7 months (range, 1-22). One patient with metastatic melanoma experienced intratumoral hemorrhage during the follow-up period. Survival was found to be associated with score of more than 70 on Karnofsky performance status and low recursive partitioning analysis class (class 1 or 2), in terms of favorable prognostic factors.

CONCLUSION

GKRS was found to be safe and effective for management of brainstem metastasis. The integral clinical status of patient seems to be important in determining the overall survival time.

The role of surgery, radiosurgery and whole brain radiation therapy in the management of patients with metastatic brain tumors

Brain tumors constitute the most common intracranial tumor. Management of brain metastases has become increasingly complex as patients with brain metastases are living longer and more treatment options develop. The goal of this paper is to review the role of stereotactic radiosurgery (SRS), whole brain radiation therapy (WBRT), and surgery, in isolation and in combination, in the contemporary treatment of brain metastases. Surgery and SRS both offer management options that may help to optimize therapy in selected patients. WBRT is another option but can lead to late toxicity and suboptimal local control in longer term survivors. Improved prognostic indices will be critical for selecting the best therapies. Further prospective trials are necessary to continue to elucidate factors that will help triage patients to the proper brain-directed therapy for their cancer.

Treatment of cavernous sinus tumors with linear accelerator radiosurgery

Since 1989, 79 patients with benign or malignant cavernous sinus tumors, have been treated at Stanford University with linear accelerator (linac) radiosurgery. Radiosurgery has been used as (1) a planned second-stage procedure for residual tumor following surgery, (2) primary treatment for patients whose medical conditions preclude surgery, (3) palliation of malignant lesions, and (4) definitive treatment for small, well-localized, poorly accessible tumors. Mean patient age was 52 years (range, 18 to 88); there were 28 males and 51 females. Sixty-one patients had benign tumors; 18 had malignant tumors. Mean tumor volume was 6.8 cm(3) (range 0.5 to 22.5 cm(3)) covered with an average of 2.3 isocenter (range, 1 to 5). Radiation dose averaged 17.1 Gy. Mean follow-up was 46 months. Tumor control or shrinkage, or both, varied with pathology. Radiographic tumor improvement was most pronounced in malignant lesions, with greater than 85% showing reduction in tumor size; benign tumors (meningiomas and schwannomas) had a 63% control rate and 37% shrinkage rate, with none enlarging. We concluded that stereotactic radiosurgery is a valuable tool in managing cavernous sinus tumors. There was excellent control and stabilization of benign tumors and palliation of malignant lesions.

Multimodality treatment of brain metastases: an institutional survival analysis of 275 patients

Background

Whole brain radiation therapy (WBRT), surgical resection, stereotactic radiosurgery (SRS), and combinations of the three modalities are used in the management of patients with metastatic brain tumors. We present the previously unreported survival outcomes of 275 patients treated for newly diagnosed brain metastases at Cancer Care Northwest and Gamma Knife of Spokane between 1998 and 2008.

Methods

The effects treatment regimen, age, Eastern Cooperative Oncology Group-Performance Status (ECOG-PS), primary tumor histology, number of brain metastases, and total volume of brain metastases have on patient overall survival were analyzed. Statistical analysis was performed using Kaplan-Meier survival curves, Andersen 95% confidence intervals, approximate confidence intervals for log hazard-ratios, and multivariate Cox proportional hazard models.

Results

The median clinical follow up time was 7.2 months. On multivariate analysis, survival statistically favored patients treated with SRS alone when compared to patients treated with WBRT alone (p < 0.001), patients treated with resection with SRS when compared to patients treated with SRS alone (p = 0.020), patients in ECOG-PS class 0 when compared to patients in ECOG-PS classes 2 (p = 0.04), 3 (p < 0.001), and 4 (p < 0.001), patients in the non-small-cell lung cancer group when compared to patients in the combined melanoma and renal-cell carcinoma group (p < 0.001), and patients with breast cancer when compared to patients with non-small-cell lung cancer (p < 0.001).

Conclusions

In our analysis, patients benefited from a combined modality treatment approach and physicians must consider patient age, performance status, and primary tumor histology when recommending specific treatments regimens.

The role of stereotactic radiosurgery in the management of patients with newly diagnosed brain metastases: a systematic review and evidence-based clinical practice guideline

QUESTION

Should patients with newly-diagnosed metastatic brain tumors undergo stereotactic radiosurgery (SRS) compared with other treatment modalities? Target population These recommendations apply to adults with newly diagnosed solid brain metastases amenable to SRS; lesions amenable to SRS are typically defined as measuring less than 3 cm in maximum diameter and producing minimal (less than 1 cm of midline shift) mass effect. Recommendations SRS plus WBRT vs. WBRT alone Level 1 Single-dose SRS along with WBRT leads to significantly longer patient survival compared with WBRT alone for patients with single metastatic brain tumors who have a KPS > or = 70.Level 1 Single-dose SRS along with WBRT is superior in terms of local tumor control and maintaining functional status when compared to WBRT alone for patients with 1-4 metastatic brain tumors who have a KPS > or =70.Level 2 Single-dose SRS along with WBRT may lead to significantly longer patient survival than WBRT alone for patients with 2-3 metastatic brain tumors.Level 3 There is class III evidence demonstrating that single-dose SRS along with WBRT is superior to WBRT alone for improving patient survival for patients with single or multiple brain metastases and a KPS<70 [corrected].Level 4 There is class III evidence demonstrating that single-dose SRS along with WBRT is superior to WBRT alone for improving patient survival for patients with single or multiple brain metastases and a KPS < 70. SRS plus WBRT vs. SRS alone Level 2 Single-dose SRS alone may provide an equivalent survival advantage for patients with brain metastases compared with WBRT + single-dose SRS. There is conflicting class I and II evidence regarding the risk of both local and distant recurrence when SRS is used in isolation, and class I evidence demonstrates a lower risk of distant recurrence with WBRT; thus, regular careful surveillance is warranted for patients treated with SRS alone in order to provide early identification of local and distant recurrences so that salvage therapy can be initiated at the soonest possible time. Surgical Resection plus WBRT vs. SRS +/- WBRT Level 2 Surgical resection plus WBRT, vs. SRS plus WBRT, both represent effective treatment strategies, resulting in relatively equal survival rates. SRS has not been assessed from an evidence-based standpoint for larger lesions (>3 cm) or for those causing significant mass effect (>1 cm midline shift). Level 3: Underpowered class I evidence along with the preponderance of conflicting class II evidence suggests that SRS alone may provide equivalent functional and survival outcomes compared with resection + WBRT for patients with single brain metastases, so long as ready detection of distant site failure and salvage SRS are possible. SRS alone vs. WBRT alone Level 3 While both single-dose SRS and WBRT are effective for treating patients with brain metastases, single-dose SRS alone appears to be superior to WBRT alone for patients with up to three metastatic brain tumors in terms of patient survival advantage.

Gamma Knife surgery for brain metastases from gastrointestinal cancer

OBJECT

Brain metastases from gastrointestinal cancers are rare. However, the incidence is increasing because patients with gastrointestinal carcinoma tend to live longer due to earlier diagnosis and more effective treatment of systemic disease. The purpose of this study was to evaluate the efficacy of Gamma Knife surgery (GKS) for the treatment of brain metastases from gastrointestinal cancers.

METHODS

The authors performed a retrospective review of 40 patients (18 women and 22 men) who had undergone GKS to treat a total of 118 metastases from gastrointestinal cancers between January 1996 and December 2006. The mean patient age was 58.7 years, and the mean Karnofsky Performance Scale (KPS) score was 70. There were 7 patients with esophageal cancer, 25 with colon cancer, 5 with rectal cancer, 2 with pancreatic cancer, and 1 with gastric cancer. Nineteen patients were treated with whole-brain radiotherapy and/or local brain radiotherapy before GKS. Twenty-four patients had extracranial metastases, and 3 had an additional primary cancer. The mean metastatic brain tumor volume was 4.3 cm3, and the mean maximum tumor dose varied from 17.1 to 76.7 Gy (mean 41.8 Gy).

RESULTS

Follow-up imaging studies were available in 25 patients with a total of 90 treated metastases. The results demonstrate a tumor control rate of 91%. The median survival time was 6.7 months, and the 6-month and 1-year survival rates were 55 and 25%, respectively. A univariate analysis revealed that the KPS score (<or=70 vs >or=80) was significant (p=0.018) for improved survival.

CONCLUSIONS

Results in this series suggest that GKS can be an effective tool for the treatment of brain metastases from gastrointestinal cancer.

Clinical analysis of novalis stereotactic radiosurgery for brain metastases

OBJECTIVE

The authors analyzed the effectiveness and therapeutic response of Novalis shaped beam radiosurgery for metastatic brain tumors, and the prognostic factors which influenced the outcome.

METHODS

We performed a retrospective analysis of 106 patients who underwent 159 treatments for 640 metastatic brain lesions between January 2000 and April 2008. The pathologies of the primary tumor were mainly lung (45.3%), breast (18.2%) and GI tract (13.2%). We classified the patients using Radiation Therapy Oncology Group Recursive Partitioning Analysis (RPA) and then analyzed the survival and prognostic factors according to the Kaplan Meier method and univariate analysis.

RESULTS

The overall median actuarial survival rate was 7.3 months from the time of first radiosurgery treatment while 1 and 2 year actuarial survival estimates were 31% and 14.4%, respectively. Median actuarial survival rates for RPA classes I, II, and III were 31.3 months, 7.5 months and 1.7 months, respectively. Patients' life spans, higher Karnofsky performance scores and age correlated closely with RPA classes. However, sex and the number of lesions were not found to be significantly associated with length of survival.

CONCLUSION

This result suggests that Novalis radiosurgery can be a good treatment option for treatment of the patients with brain metastases.

Radiosurgery for recurrent brain metastases after whole-brain radiotherapy : factors affecting radiation-induced neurological dysfunction

OBJECTIVE

We retrospectively analyzed survival, local control rate, and incidence of radiation toxicities after radiosurgery for recurrent metastatic brain lesions whose initial metastases were treated with whole-brain radiotherapy. Various radiotherapeutical indices were examined to suggest predictors of radiation-related neurological dysfunction.

METHODS

In 46 patients, total 100 of recurrent metastases (mean 2.2, ranged 1-10) were treated by CyberKnife radiosurgery at average dose of 23.1 Gy in 1 to 3 fractions. The median prior radiation dose was 32.7 Gy, the median time since radiation was 5.0 months, and the mean tumor volume was 12.4 cm(3). Side effects were expressed in terms of radiation therapy oncology group (RTOG) neurotoxicity criteria.

RESULTS

Mass reduction was observed in 30 patients (65%) on MRI. After the salvage treatment, one-year progression-free survival rate was 57% and median survival was 10 months. Age (<60 years) and tumor volume affected survival rate (p=0.03, each). Acute (</=1 month) toxicity was observed in 22% of patients, subacute and chronic (>6 months) toxicity occurred in 21%, respectively. Less acute toxicity was observed with small tumors (<10 cm(3), p=0.03), and less chronic toxicity occurred at lower cumulative doses (<100 Gy, p=0.004). "Radiation toxicity factor" (cumulative dose times tumor volume of <1,000 Gyxcm(3)) was a significant predictor of both acute and chronic CNS toxicities.

CONCLUSION

Salvage CyberKnife radiosurgery is effective for recurrent brain metastases in previously irradiated patients, but careful evaluation is advised in patients with large tumors and high cumulative radiation doses to avoid toxicity.

Current concepts in stereotactic radiosurgery - a neurosurgical and radiooncological point of view

Stereotactic radiosurgery is related to the history of "radiotherapy" and "stereotactic neurosurgery". The concepts for neurosurgeons and radiooncologists have been changed during the last decade and have also transformed neurosurgery. The gamma knife and the stereotactically modified linear accelerator (LINAC) are radiosurgical equipments to treat predetermined intracranial targets through the intact skull without damaging the surrounding normal brain tissue. These technical developments allow a more precise intracranial lesion control and offer even more conformal dose plans for irregularly shaped lesions. Histological determination by stereotactic biopsy remains the basis for any otherwise undefined intracranial lesion. As a minimal approach, it allows functional preservation, low risk and high sensitivity. Long-term results have been published for various indications. The impact of radiosurgery is presented for the management of gliomas, metastases, brain stem lesions, benign tumours and vascular malformations and selected functional disorders such as trigeminal neuralgia. In AVM's it can be performed as part of a multimodality strategy including resection or endovascular embolisation. Finally, the technological advances in radiation oncology as well as stereotactic neurosurgery have led to significant improvements in radiosurgical treatment opportunities. Novel indications are currently under investigation. The combination of both, the neurosurgical and the radiooncological expertise, will help to minimize the risk for the patient while achieving a greater treatment success.

Gamma knife radiosurgery for metastatic brain tumors from thyroid cancer

OBJECTIVE

We report our experience using gamma knife radiosurgery (GKR) for brain metastasis from thyroid cancer, which is extremely rare.

METHODS

Between 1995 and 2007, 9 patients with 26 metastatic brain tumor(s) from thyroid cancer underwent GKR. The mean patient age was 58 years (range: 10-78). Seven patients had metastases from papillary thyroid cancer, and two from medullary thyroid cancer. Five patients had solitary tumors, and four patients had multiple metastases. Three patients who had multiple metastases also underwent whole brain radiation therapy (WBRT). The mean tumor volume was 2.4 cc (range: 0.03-14.0). A median margin dose of 18.0 Gy (range: 12-20) was delivered to the tumor margin.

RESULTS

Tumor control was obtained in 25 out of 26 tumors (96%). The median progression-free period after GKR was 12 months (range: 4-53). The overall median survival after GKR was 33 months (range: 5-54). There were no procedure-related complications and six patients are still living 5-54 months after GKR.

CONCLUSIONS

Radiosurgery is an effective and minimally invasive strategy for management of brain metastases form thyroid cancer.

Microsurgery plus whole brain irradiation versus Gamma Knife surgery alone for treatment of single metastases to the brain: a randomized controlled multicentre phase III trial

BACKGROUND

Is Gamma Knife surgery alone as effective as surgery plus whole brain irradiation (WBRT) for patients with a single, small-sized brain metastasis?

METHODS

Patients aged between 18 and 80 years harboring a single, resectable metastasis < or =3 cm in diameter, a Karnofsky performance score (KPS) > or =70, and a stable systemic disease were randomly assigned to microsurgery plus WBRT or Gamma Knife surgery alone. The primary end point was length of survival, secondary end points were recurrence of tumor in the brain, health related quality of life, and treatment related toxicity.

RESULTS

Due to poor patient accrual, the study was stopped prematurely. The final analysis was based on 33 patients in the surgery and 31 patients in the radiosurgery group. Treatment results did not differ in terms of survival (P = 0.8), neurological death rates (P = 0.3), and freedom from local recurrence (P = 0.06). Patients of the radiosurgery group experienced more often distant recurrences (P = 0.04); after adjustment for the effects of salvage radiosurgery this difference was lost (P = 0.4). Radiosurgery was associated with a shorter hospital stay, less frequent and shorter timed steroid application (P < or = 0.001), and lower frequency of grade 1/2 toxicities (according to the RTOG/EORTC CNS toxicity criteria, P < or = 0.01). Improved scores for role functioning and quality of life were seen 6 weeks after radiosurgery (P < 0.05); this difference was lost 6 months after treatment.

CONCLUSIONS

In patients harboring a single, small-sized metastasis, Gamma Knife surgery alone is less invasive; local tumor control seems to be as high as after surgery plus WBRT. Distant tumor control, however, is significantly less frequently achieved (after radiosurgery alone). The role of radiosurgical salvage therapy (alternatively to WBRT) for distant tumor control deserves further prospective evaluation.

Palliative care in lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition)

GOALS/OBJECTIVES: To review the scientific evidence on symptoms and specific complications that are associated with lung cancer, and the methods available to palliate those symptoms and complications.

METHODS

MEDLINE literature review (through March 2006) for all studies published in the English language, including case series and case reports, since 1966 using the following medical subject heading terms: bone metastases; brain metastases; cough; dyspnea; electrocautery; hemoptysis; interventional bronchoscopy; laser; pain management; pleural effusions; spinal cord metastases; superior vena cava syndrome; and tracheoesophageal fistula.

RESULTS

Pulmonary symptoms that may require palliation in patients who have lung cancer include those caused by the primary cancer itself (dyspnea, wheezing, cough, hemoptysis, chest pain), or locoregional metastases within the thorax (superior vena cava syndrome, tracheoesophageal fistula, pleural effusions, ribs, and pleura). Respiratory symptoms can also result from complications of lung cancer treatment or from comorbid conditions. Constitutional symptoms are common and require attention and care. Symptoms referable to distant extrathoracic metastases to bone, brain, spinal cord, and liver pose additional problems that require a specific response for optimal symptom control. There are excellent scientific data regarding the management of many of these issues, with lesser evidence from case series or expert opinion on other aspects of providing palliative care for lung cancer patients.

CONCLUSIONS

Palliation of symptoms and complications in lung cancer patients is possible, and physicians who provide such care must be knowledgeable about these issues.

Treatment and prognosis of brain metastases from breast cancer

BACKGROUND

To analyze retrospectively the results of treatments for patients with brain metastases from breast cancer.

MATERIALS AND METHODS

The records of 65 breast cancer patients with brain metastases who were treated between 1985 and 2005 were reviewed. For brain metastases, 11 patients (17%) were treated with surgical resection followed by radiotherapy, and the remaining 54 patients were treated with radiotherapy alone. Systemic chemotherapy was also administered to 11 patients after brain radiotherapy.

RESULTS

The overall median survival for all patients was 6.1 months (range, 0.4-82.2 months). In univariate analysis, treatment modality, Karnofsky performance status (KPS), administration of systemic chemotherapy, extracranial disease status and total radiation dose each had significant impact on overall survival, and in multivariate analysis, treatment modality, KPS and administration of systemic chemotherapy were significant prognostic factors. Eight patients survived for more than 2 years after the diagnosis of brain metastases, and all these patients were treated with surgical resection and/or systemic chemotherapy in addition to radiotherapy. For the 45 patients treated with palliative radiotherapy (without systemic chemotherapy), the improvements in neurological symptoms were observed in 35 patients (78%), with the median duration of improvement of 3.1 months (range, 1.5-4.4 months).

CONCLUSIONS

The prognoses for patients with brain metastases from breast cancer were generally poor, although selected patients may survive longer with intensive brain tumor treatment, such as surgical resection and/or systemic chemotherapy in addition to brain radiotherapy. For patients with unfavorable prognoses, palliative radiotherapy was effective in improving the quality of the remaining lifetime.