Radiosurgery for re-irradiation of brain metastasis: results in 54 patients

Opportunities and Alternatives of Modern Radiation Oncology and Surgery for the Management of Resectable Brain Metastases

Postsurgical radiotherapy (RT) has been early proven to prevent local tumor recurrence, initially performed with whole brain RT (WBRT). Subsequent to disadvantageous cognitive sequalae for the patient and the broad distribution of modern linear accelerators, focal irradiation of the tumor has omitted WBRT in most cases. In many studies, the effectiveness of local RT of the resection cavity, either as single-fraction stereotactic radiosurgery (SRS) or hypo-fractionated stereotactic RT (hFSRT), has been demonstrated to be effective and safe. However, whereas prospective high-level incidence is still lacking on which dose and fractionation scheme is the best choice for the patient, further ablative techniques have come into play. Neoadjuvant SRS (N-SRS) prior to resection combines straightforward target delineation with an accelerated post-surgical phase, allowing an earlier start of systemic treatment or rehabilitation as indicated. In addition, low-energy intraoperative RT (IORT) on the surgical bed has been introduced as another alternative to external beam RT, offering sterilization of the cavity surface with steep dose gradients towards the healthy brain. This consensus paper summarizes current local treatment strategies for resectable brain metastases regarding available data and patient-centered decision-making.

Re-irradiation in patients with progressive or recurrent brain metastases from extracranial solid tumors: A novel prognostic index

BACKGROUND

Most studies evaluating factors associated with the survival of patients with brain metastases (BM) have focused on patients with newly diagnosed BM. This study aimed to identify prognostic factors associated with survival after brain re-irradiation in order to develop a new prognostic index.

METHODS

This 5-year retrospective study included patients treated with repeat-radiotherapy for recurrent BM at the "Instituto Nacional de Cancerología" of Mexico between 2015 and 2019. Significant variables in the multivariate Cox regression analysis were used to create the brain re-irradiation index (BRI). Survival and group comparisons were performed using the Kaplan-Meier method and the log-rank test.

RESULTS

Fifty-seven patients receiving brain re-irradiation were identified. Most patients were women (75.4%) with a mean age at BM diagnosis of 51.4 years. Lung and breast cancer were the most prevalent neoplasms (43.9% each). Independent prognostic factors for shorter survival after re-irradiation were: Age >50 years (hazard ratio [HR]:2.5 [95% confidence interval [CI], 1.1-5.8]; p = 0.026), uncontrolled primary tumor (HR:5.5 [95% CI, 2.2-13.5]; p < 0.001), lesion size >20 mm (4.6 [95% CI, 1.7-12.2]; p = 0.002), and an interval <12 months between radiation treatments (HR:4.3 [95% CI, 1.7-10.6]; p = 0.001). Median survival (MS) after re-irradiation was 14.6 months (95% CI, 8.2-20.9).MS of patients stratified according to the BRI score was 17.38, 10.34, and 2.82 months, with significant differences between all groups.

CONCLUSIONS

The new BRI can be easily implemented for the prognostic classification of cancer patients with progressive or recurrent BM from extracranial solid tumors.

Efficacy and Safety of a Second Course of Stereotactic Radiation Therapy for Locally Recurrent Brain Metastases: A Systematic Review

Simple Summary

Approximately 30% of patients diagnosed with cancer will ultimately develop brain metastases. Many improvements have been made in systemic and local cancer treatments, which have increased overall survival but also, as a consequence, the number of patients who present with local recurrence following intracranial stereotactic radiotherapy. The management of these recurrences remains controversial. The aim of our review is to evaluate the efficacy and tolerance of a second course of stereotactic radiotherapy.

Abstract

Recent advances in cancer treatments have increased overall survival and consequently, local failures (LFs) after stereotactic radiotherapy/radiosurgery (SRS/SRT) have become more frequent. LF following SRS or SRT may be treated with a second course of SRS (SRS2) or SRT (SRT2). However, there is no consensus on whenever to consider reirradiation. A literature search was conducted according to PRISMA guidelines. Analysis included 13 studies: 329 patients (388 metastases) with a SRS2 and 135 patients (161 metastases) with a SRT2. The 1-year local control rate ranged from 46.5% to 88.3%. Factors leading to poorer LC were histology (melanoma) and lack of prior whole-brain radiation therapy, large tumor size and lower dose at SRS2/SRT2, poorer response at first SRS/SRT, poorer performance status, and no controlled extracranial disease. The rate of radionecrosis (RN) ranged from 2% to 36%. Patients who had a large tumor volume, higher dose and higher value of prescription isodose line at SRS2/SRT2, and large overlap between brain volume irradiated at SRS1/SRT1 and SRS2/SRT2 at doses of 18 and 12 Gy had a higher risk of developing RN. Prospective studies involving a larger number of patients are still needed to determine the best management of patients with local recurrence of brain metastases

Challenges and Novel Opportunities of Radiation Therapy for Brain Metastases in Non-Small Cell Lung Cancer

Simple Summary

Lung cancer is the most common primary malignancy that tends to metastasize to the brain. Owing to improved survival of lung cancer patients, the prevalence of brain metastases is a matter of growing concern. Brain radiotherapy remains the mainstay in the management of metastatic CNS disease. However, new targeted therapies such as the tyrosine kinase or immune checkpoint inhibitors have demonstrated intracranial activity and promising tumor response rates. Here, we review the current and emerging therapeutical strategies for brain metastases from non-small cell lung cancer, both brain-directed and systemic, as well as the uncertainties that may arise from their combination.

Abstract

Approximately 20% patients with non-small cell lung cancer (NSCLC) present with CNS spread at the time of diagnosis and 25–50% are found to have brain metastases (BMs) during the course of the disease. The improvement in the diagnostic tools and screening, as well as the use of new systemic therapies have contributed to a more precise diagnosis and prolonged survival of lung cancer patients with more time for BMs development. In the past, most of the systemic therapies failed intracranially because of the inability to effectively cross the blood brain barrier. Some of the new targeted therapies, especially the group of tyrosine kinase inhibitors (TKIs) have shown durable CNS response. However, the use of ionizing radiation remains vital in the management of metastatic brain disease. Although a decrease in CNS-related deaths has been achieved over the past decade, many challenges arise from the need of multiple and repeated brain radiation treatments, which carry along not insignificant risks and toxicity. The combination of stereotactic radiotherapy and systemic treatments in terms of effectiveness and adverse effects, such as radionecrosis, remains a subject of ongoing investigation. This review discusses the challenges of the use of radiation therapy in NSCLC BMs in view of different systemic treatments such as chemotherapy, TKIs and immunotherapy. It also outlines the future perspectives and strategies for personalized BMs management.

Central Nervous System Cancers, Version 3.2020, NCCN Clinical Practice Guidelines in Oncology

The NCCN Guidelines for Central Nervous System (CNS) Cancers focus on management of adult CNS cancers ranging from noninvasive and surgically curable pilocytic astrocytomas to metastatic brain disease. The involvement of an interdisciplinary team, including neurosurgeons, radiation therapists, oncologists, neurologists, and neuroradiologists, is a key factor in the appropriate management of CNS cancers. Integrated histopathologic and molecular characterization of brain tumors such as gliomas should be standard practice. This article describes NCCN Guidelines recommendations for WHO grade I, II, III, and IV gliomas. Treatment of brain metastases, the most common intracranial tumors in adults, is also described.

Complex Clinical Decision-Making Process of Re-Irradiation

As patients live longer with their cancer as a result of more effective treatment, recurrences and second malignancies in a previously irradiated field are an increasing challenge. The technical advances that enable high-dose radiation to limited volumes, excluding critical normal tissues, have increased the use of re-irradiation for many tumour sites. Minimising the volume, selecting patients with good performance status, negative metastatic screening and longer disease-free intervals are important principles. Despite this there is a narrow therapeutic window, and careful consideration with open discussion, including the patient, of the probable benefit and the implications of potential toxicities will always be essential. In this overview we evaluate the various radiobiological factors that need to be considered for re-irradiation, tissue recovery and dose tolerances in the setting of re-irradiation and summarise the available literature to guide clinicians in their decision-making for re-irradiation to primary and metastatic site/s of disease.

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.

Stereotactic reirradiation for local failure of brain metastases following previous radiosurgery: Systematic review and meta-analysis

INTRODUCTION

Local failure (LF) following stereotactic radiosurgery (SRS) of brain metastases (BM) may be treated with a second course of SRS (SRS2), though this procedure may increase the risk of symptomatic radionecrosis (RN).

METHODS

A literature search was conducted according to PRISMA to identify studies reporting LF, overall survival (OS) and RN rates following SRS2. Meta-analysis was performed to identify predictors of RN.

RESULTS

Analysis included 11 studies (335 patients,389 metastases). Pooled 1-year LF was 24 %(CI95 % 19-30 %): heterogeneity was acceptable (I2 = 21.4 %). Median pooled OS was 14 months (Confidence Interval 95 %, CI95 % 8.8-22.0 months). Cumulative crude RN rate was 13 % (95 %CI 8 %-19 %), with acceptable heterogeneity (I2 = 40.3 %). Subgroup analysis showed higher RN incidence in studies with median patient age ≥59 years (13 % [95 %CI 8 %-19 %] vs 7 %[95 %CI 3 %-12 %], p = 0.004) and lower incidence following prior Whole Brain Radiotherapy (WBRT, 19 %[95 %CI 13 %-25 %] vs 7%[95 %CI 3 %-13 %], p = 0.004).

CONCLUSIONS

SRS2 is an effective strategy for in-site recurrence of BM previously treated with SRS.

Repeated stereotactic radiosurgery for recurrent brain metastases: An effective strategy to control intracranial oligometastatic disease

Due to improvements in systemic therapies and longer survivals, cancer patients frequently present with recurrent brain metastases (BM). The optimal therapeutic strategies for limited brain relapse remain undefined. We analyzed tumor control and survival in patients treated with salvage focal radiotherapy in our center. Thirty-three patients with 112 BM received salvage stereotactic radiosurgery (SRS) or fractionated stereotactic radiotherapy (FSRT) for local or regional recurrences. Local progression was observed in 11 BM (9.8 %). After 1 year, 72 % of patients were free of distant brain failure, and the 2-year overall survival (OS) was 37.7 %. No increase in toxicity or neurologically related deaths were observed. The 2- and 3-year whole brain radiation therapy free survival (WFS) rates were 92.9 % and 77.4 %, respectively. Hence, focal radiotherapy is a feasible salvage of recurrent BM in selected group of patients with limited brain disease, achieving a maintained intracranial control and less neurological toxicity.

Re-Irradiation of Brain Metastases and Metastatic Spinal Cord Compression: Clinical Practice Suggestions

The recent improvements of therapeutic approaches in oncology have allowed a certain number of patients with advanced disease to survive much longer than in the past. So, the number of cases with brain metastases and metastatic spinal cord compression has increased, as has the possibility of developing a recurrence in areas of the central nervous system already treated with radiotherapy.

Clinicians are reluctant to perform re-irradiation of the brain, because of the risk of severe side effects. The tolerance dose for the brain to a single course of radiotherapy is 50–60 Gy in 2 Gy daily fractions. New metastases appear in 22–73% of the cases after whole brain radiotherapy, but the percentage of re-irradiated patients is 3–10%. An accurate selection must be made before giving an indication to re-irradiation. Patients with Karnofsky performance status >70, age <65 years, controlled primary and no extracranial metastases are those with the best prognosis. The absence of extracranial disease was the most significant factor in conditioning survival, and maximum tumor diameter was the only variable associated with an increased risk of unacceptable acute and/or chronic neurotoxicity. Re-treatment of brain metastases can be done with whole brain radiotherapy, stereotactic radiosurgery or fractionated stereotactic radiotherapy. Most patients had no relevant radiation-induced toxicity after a second course of whole brain radiotherapy or stereotactic radiosurgery. There are few data on fractionated stereotactic radiotherapy in the re-irradiation of brain metastases.

In general, the incidence of an “in-field” recurrence of spinal metastasis varies from 2.5–11% of cases and can occur 2–40 months after the first radiotherapy cycle. Radiation-induced myelopathy can occur months or years (6 months-7 years) after radiotherapy, and the pathogenesis remains obscure. Higher radiotherapy doses, larger doses per fraction, and previous exposure to radiation could be associated with a higher probability of developing radiation-induced myelopathy. Experimental data indicate that also the total dose of the first and second radiotherapy, interval to re-treatment, length of the irradiated spinal cord, and age of the treated animals influence the risk of radiation-induced myelopathy. An α/β ratio of 1.9–3 Gy could be generally the reference value for fractionated radiotherapy. However, when fraction sizes are up to 5 Gy, the linear-quadratic equation become a less valid model. The early diagnosis of relapse is crucial in conditioning response to re-treatment.

A prospective phase II trial on reirradiation of brain metastases with radiosurgery

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Reirradiation with radiosurgery of brain metastases is feasible and safe.

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Good KPS and controlled systemic disease are most important selection criteria.

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An accurate patient selection is essential to avoid brain toxicity.

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If diameter is ≤ 2 cm and dose ≤ 20 Gy local control is high without late toxicity.

Purpose

In our previous published trial on radiosurgery (SRS) of recurrent brain metastases (BM) after whole brain radiotherapy (WBRT), Karnofsky performance status (KPS) and administered dose conditioned outcome and late toxicity, respectively. Brain radionecrosis was registered in 6% of patients. With the aim to obtain similar satisfactory outcomes and limit toxicity, we started a phase II trial in which reirradiation of BM with SRS were done using a tighter patient selection.

Materials and methods

Patients with BM recurring after WBRT were recruited for reirradiation with SRS. Only patients with good KPS (≥70), good neurologic functional score (NFS 0-1) and lesions with a diameter ≤20 mm were considered eligible for retreatment. Dose exceeding 20 Gy was never administered.

Results

The 59 patients reirradiated had 109 BM with a diameter range of 6–20 mm. Median interval between prior WBRT and SRS was 15 months and median SRS administered dose was 18 Gy (range 10–20 Gy). Complete and partial response (CR, PR) was obtained in 42% of patients with 2 years of control rate of 81%. Median overall survival (OS) after reirradiation was 14 months. No radionecrosis was detected.

Conclusions

Analysis of our current trial compared with results of our previous data suggests that a tighter patient selection (KPS ≥ 70; NFS 0-1, BM with ≤20 mm of diameter) and SRS dose ≤20 Gy allowed a high OS rate, a good percentage of CR and PR which last for >2 years, and no brain radionecrosis.

Stereotactic Radiation Therapy for Renal Cell Carcinoma Brain Metastases in the Tyrosine Kinase Inhibitors Era: Outcomes of 120 Patients

BACKGROUND

The objective of the study was to evaluate the outcomes in terms of efficacy and safety of a large consecutive series of 362 patients with renal cell carcinoma (RCC) brain metastases treated using stereotactic radiosurgery (SRS) in the tyrosine kinase inhibitor (TKI) era.

PATIENTS AND METHODS

From 2005 to 2015, 362 consecutive patients with brain metastases from RCC were treated using SRS in 1 fraction: 226 metastases (61 patients) using Gamma-Knife at a median of 18 Gy (50% isodose line); 136 metastases (63 patients) using linear accelerator at a median of 16 Gy (70% isodose line). The median patient age was 58 years. At the first SRS, 37 patients (31%) received a systemic treatment. Among systemic therapies, TKIs were the most common (65%).

RESULTS

The local control rates were 94% and 92% at 12 and 36 months, respectively. In multivariate analysis, a minimal dose >17 Gy and concomitant TKI treatment were associated with higher rates of local control. The overall survival rates at 12 and 36 months were 52% and 29%, respectively. In multivariate analysis, factors associated with poor survival included age ≥65 years, lower score index for SRS, concomitant lung metastases, time between RCC diagnosis and first systemic metastasis ≤4 months, occurrence during treatment with a systemic therapy, no history of neurosurgery, and persistence or occurrence of neurological symptoms at 3 months after SRS. Seventeen patients had Grade III/IV adverse effects of whom 3 patients presented a symptomatic radionecrosis.

CONCLUSION

SRS is highly effective in patients with brain metastases from RCC. Its association with TKIs does not suggest higher risk of neurologic toxicity.

Reirradiation of Recurrent Brain Metastases: Where Do We Stand?

Brain metastases occur in a large portion of patients with cancer. Although advances in radiotherapy have helped to improve survival, they have also raised questions regarding the best modality for retreatment in the context of recurrent disease. The spectrum of treatment options for recurrent intracranial metastatic disease after previous radiotherapy includes salvage stereotactic radiosurgery, whole brain radiotherapy, and brachytherapy. We have comprehensively reviewed the existing data on the efficacy and toxicity of the various reirradiation treatment modalities. We examined the key clinical considerations that guide patient selection, such as dose, tumor size, interval to retreatment, and local control and survival rates.

Second course of stereotactic radiosurgery for locally recurrent brain metastases: Safety and efficacy

In the present study, we have evaluated the efficacy and toxicity of repeated brain metastases (BM) stereotactic radiosurgery (SRS2) following local failure of a prior radiosurgical procedure (SRS1). Between December 1996 and August 2015, 30 patients with 36 BM underwent SRS2 with a median dose of 18Gy. All BM were located outside critical structures. Following SRS2, local control at 6 months and one year were respectively 82.9% (IC 95%: 67.6–91.9) and 67.8% (IC 95%: 51–81). On multivariate analysis, planning target volume (PTV) < 3cc (HR: 0.19 (0.1–0.52)) and whole brain radiotherapy (WBRT) prior to SRS2 (HR: 0.25 (0.1–0.64)) were significantly associated with a better local control. One- and two-year overall survival rates after SRS2 were respectively 65.5% (IC 95%: 47.3–80%) and 27.6% (IC 95%: 14.7–45.7). Median overall survival following SRS2 was 14.2 months (range 1–106). Nineteen (63%) patients died from progressive systemic disease. Three (10%) patients died from out-field progressive brain disease and 8 (27%) in-field. Concerning toxicities, edema, radionecrosis, and hemorrhages were identified in 5 (12.8%), 4 (10.2%), and 5 (12.8%) patients respectively. No toxicity resulted in a neurological deficit. On univariate analysis, toxicities were significantly associated with PTV > 7cc (p = 0.02) and all patients had a WBRT before SRS2. A second course of SRS for locally recurrent brain metastases showed encouraging rates of local control. This treatment led to acceptable toxicities, especially for brain metastases smaller than 7cc, in our selected cohort of patients with BM located outside critical structures. Further studies are needed.

Efficacy, safety and outcome of frameless image-guided robotic radiosurgery for brain metastases after whole brain radiotherapy

Estimating efficacy, safety and outcome of frameless image-guided robotic radiosurgery for the treatment of recurrent brain metastases after whole brain radiotherapy (WBRT). We performed a retrospective single-center analysis including patients with recurrent brain metastases after WBRT, who have been treated with single session radiosurgery, using the CyberKnife® Radiosurgery System (CKRS) (Accuray Inc., CA) between 2011 and 2016. The primary end point was local tumor control, whereas secondary end points were distant tumor control, treatment-related toxicity and overall survival. 36 patients with 140 recurrent brain metastases underwent 46 single session CKRS treatments. Twenty one patients had multiple brain metastases (58%). The mean interval between WBRT and CKRS accounted for 2 years (range 0.2-7 years). The median number of treated metastases per treatment session was five (range 1-12) with a tumor volume of 1.26 ccm (mean) and a median tumor dose of 18 Gy prescribed to the 70% isodose line. Two patients experienced local tumor recurrence within the 1st year after treatment and 13 patients (36%) developed novel brain metastases. Nine of these patients underwent additional one to three CKRS treatments. Eight patients (22.2%) showed treatment-related radiation reactions on MRI, three with clinical symptoms. Median overall survival was 19 months after CKRS. The actuarial 1-year local control rate was 94.2%. CKRS has proven to be locally effective and safe due to high local tumor control rates and low toxicity. Thus CKRS offers a reliable salvage treatment option for recurrent brain metastases after WBRT.

Cesium-131 brachytherapy for recurrent brain metastases: durable salvage treatment for previously irradiated metastatic disease

OBJECTIVE Managing patients whose intraparenchymal brain metastases recur after radiotherapy remains a challenge. Intraoperative cesium-131 (Cs-131) brachytherapy performed at the time of neurosurgical resection may represent an excellent salvage treatment option. The authors evaluated the outcomes of this novel treatment with permanent intraoperative Cs-131 brachytherapy. METHODS Thirteen patients with 15 metastases to the brain that recurred after stereotactic radiosurgery and/or whole brain radiotherapy were treated between 2010 and 2015. Stranded Cs-131 seeds were placed as a permanent volume implant. Prescription dose was 80 Gy at 5-mm depth from the resection cavity surface. The primary end point was resection cavity freedom from progression (FFP). Resection cavity freedom from progression (FFP), regional FFP, distant FFP, median survival, overall survival (OS), and toxicity were assessed. RESULTS The median duration of follow-up after salvage treatment was 5 months (range 0.5-18 months). The patients' median age was 64 years (range 51-74 years). The median resected tumor diameter was 2.9 cm (range 1.0-5.6 cm). The median number of seeds implanted was 19 (range 10-40), with a median activity per seed of 2.25 U (range 1.98-3.01 U) and median total activity of 39.6 U (range 20.0-95.2 U). The 1-year actuarial local FFP was 83.3%. The median OS was 7 months, and 1-year OS was 24.7%. Complications included infection (3), pseudomeningocele (1), seizure (1), and asymptomatic radionecrosis (RN) (1). CONCLUSIONS After failure of prior irradiation of brain metastases, re-irradiation with intraoperative Cs-131 brachytherapy implants provides durable local control and limits the risk of RN. The authors' initial experience demonstrates that this treatment approach is well tolerated and safe for patients with previously irradiated tumors after failure of more than 1 radiotherapy regimen and that it results in excellent response rates and minimal toxicity.

Dose-Volume Response Relationship for Brain Metastases Treated with Frameless Single-Fraction Linear Accelerator-Based Stereotactic Radiosurgery

BACKGROUND

Our aim was to identify a dose-volume response relationship for brain metastases treated with frameless stereotactic radiosurgery (SRS).

METHODS

We reviewed patients who underwent frameless single-fraction linear accelerator SRS for brain metastases between 2007 and 2013 from an institutional database. Proportional hazards modeling was used to identify predictors of outcome. A ratio of maximum lesion dose per mm-diameter (Gy/mm) was constructed to establish a dose-volume relationship.

RESULTS

There were 316 metastases evaluated in 121 patients (2 - 33 mm in the largest diameter). The median peripheral dose was 18.0 Gy (range: 10.0 - 24.0 Gy). Local control was 84.8% for all lesions and was affected by location, peripheral dose, maximum dose, and lesion size (p values < 0.050). A dose-volume response relationship was constructed using the maximum dose and lesion size. A unit increase in Gy/mm was associated with decreased local failure (p = 0.005). Local control of 80%, 85%, and 90% corresponded to maximum doses per millimeter of 1.67 Gy/mm, 2.86 Gy/mm, and 4.4 Gy/mm, respectively. Toxicity was uncommon and only 1.0% of lesions developed radionecrosis requiring surgery.

CONCLUSIONS

For brain metastases less than 3 cm, a dose-volume response relationship exists between maximum radiosurgical dose and lesion size, which is predictive of local control.

Central nervous system cancers, version 2.2014. Featured updates to the NCCN Guidelines

The NCCN Guidelines for Central Nervous System Cancers provide multidisciplinary recommendations for the clinical management of patients with cancers of the central nervous system. These NCCN Guidelines Insights highlight recent updates regarding the management of metastatic brain tumors using radiation therapy. Use of stereotactic radiosurgery (SRS) is no longer limited to patients with 3 or fewer lesions, because data suggest that total disease burden, rather than number of lesions, is predictive of survival benefits associated with the technique. SRS is increasingly becoming an integral part of management of patients with controlled, low-volume brain metastases.

Local control after radiosurgery for brain metastases: predictive factors and implications for clinical decision

BACKGROUND

To evaluate the local control of brain metastases (BM) in patients treated with stereotactic radiosurgery (SRS), correlate the outcome with treatment parameters and lesion characteristics, and define its implications for clinical decisions.

METHODS

Between 2007 and 2012, 305 BM in 141 consecutive patients were treated with SRS. After exclusions, 216 BM in 100 patients were analyzed. Doses were grouped as follows: ≤15 Gy, 16-20 Gy, and ≥21 Gy. Sizes were classified as ≤10 mm and >10 mm. Local control (LC) and overall survival (OS) were estimated using the Kaplan-Meier method. Log-rank statistics were used to identify the prognostic factors affecting LC and OS. For multivariate analyses, a Cox proportional model was applied including all potentially significant variables reached on univariate analyses.

RESULTS

Median age was 54 years (18-80). Median radiological follow-up of the lesions was 7 months (1-66). Median LC and the LC at 1 year were 22.3 months and 69.7%, respectively. On univariate analysis, tumor size, SRS dose, and previous whole brain irradiation (WBRT) were significant factors for LC. Patients with lesions >10 and ≤10 mm had an LC at 1 year of 58.6% and 79.1%, respectively (p = 0.008). In lesions receiving ≤15 Gy, 16-20 Gy, and ≥21 Gy, the 1-year LC rates were 39.6%, 71.7%, and 92.3%, respectively (p < 0.001). When WBRT was done previously, LC at 1 year was 57.9% compared with 78.4% for those who did not undergo WBRT (p = 0.004). On multivariate analysis, dose remained the single most powerful prognostic factor for LC. Median OS for all patients was 17 months, with no difference among the groups.

CONCLUSIONS

Dose is the most important predictive factor for LC of BM. Doses below 16 Gy correlated with poor LC. The SRS dose as salvage treatment after previous WBRT should not be reduced unless there is a pressing reason to do so.

Feasibility and outcome of re-irradiation in the treatment of multiply recurrent pituitary adenomas

PURPOSE

This study evaluates the toxicity and outcomes of re-irradiation to the sella for pituitary adenomas.

METHODS

Patients diagnosed with a pituitary adenoma and treated with two or more courses of radiation treatment (RT) to the sella were retrospectively analyzed for: initial diagnosis, including histological type and functional status; RT modality, technique, dose, and fractionation; treatment with surgery, endocrine agents, and chemotherapy; toxicity of RT including radiation-induced optic neuropathy, radionecrosis, and radiation-induced neoplasms; and outcomes including local control, distant metastasis, biochemical control of functional tumors, and vital status at last follow-up.

RESULTS

We identified 15 patients with non-functioning pituitary adenoma (n = 6), Cushing's disease (CD) (n = 5), acromegaly (n = 3), and prolactinoma (n = 1). Initial RT was delivered using opposed lateral fields in 8 (53%), intensity-modulated radiation therapy (IMRT) in 4 (27%), fractionated stereotactic radiation therapy (FSRT) in 1 (6.7%), and stereotactic radiosurgery (SRS) in 2. The median dose was 49.5 Gy for fractionated RT and 15-25 Gy for SRS. Re-irradiation was performed a median of 5.8 years after initial RT, and delivered using lateral opposed beams (n = 1), IMRT (n = 4), linear-accelerator based SRS (n = 3), FSRT (n = 3), gamma knife surgery (n = 2), and yttrium-90 brachytherapy (n = 1). The median dose of re-irradiation was 45 Gy (range 27.9-54 Gy) for fractionated RT and 18 Gy for SRS. Radiation-induced optic neuropathy (RION) was observed in 2 (13.3%) patients, 6 months and 14 years after re-irradiation; the 5-year rate of RION was 9 %. Temporal lobe necrosis (TLN) occurred in two patients (13.3%), both of whom had received SRS. The 2- and 5-year rates of TLN were 10 and 28%. Actuarial local control rates at 2 and 5 years were 80 and 58%, respectively. Biochemical remission occurred in one of three patients with CD. Four patients (27%) ultimately developed pituitary carcinoma.

CONCLUSIONS

Re-irradiation is a feasible treatment option for local control in patients with recalcitrant pituitary adenomas, with acceptable rates of RION and TLN given the lack of options that may be available otherwise. Re-irradiation, however, did not control hormonal hypersecretion.

Central nervous system cancers

Primary and metastatic tumors of the central nervous system are a heterogeneous group of neoplasms with varied outcomes and management strategies. Recently, improved survival observed in 2 randomized clinical trials established combined chemotherapy and radiation as the new standard for treating patients with pure or mixed anaplastic oligodendroglioma harboring the 1p/19q codeletion. For metastatic disease, increasing evidence supports the efficacy of stereotactic radiosurgery in treating patients with multiple metastatic lesions but low overall tumor volume. These guidelines provide recommendations on the diagnosis and management of this group of diseases based on clinical evidence and panel consensus. This version includes expert advice on the management of low-grade infiltrative astrocytomas, oligodendrogliomas, anaplastic gliomas, glioblastomas, medulloblastomas, supratentorial primitive neuroectodermal tumors, and brain metastases. The full online version, available at NCCN. org, contains recommendations on additional subtypes.

Stereotactic radiotherapy for large solitary brain metastases

PURPOSE

To assess effectiveness and toxicity levels of stereotactic radiation therapy without whole brain radiation therapy in patients with solitary brain metastases larger than 3cm.

PATIENTS AND METHODS

Between June 2007 and March 2009, 12 patients received fractionated stereotactic radiation therapy and 24 patients underwent stereotactic radiosurgery. For the fractionated stereotactic radiation therapy group, 3×7.7Gy were delivered to the planning target volume (PTV); median volume and diameter were 29.4 cm(3) and 4.4cm, respectively. For the stereotactic radiosurgery group, 14Gy were delivered to the PTV; median volume and diameter were 15.6 cm(3) and 3.7cm, respectively.

RESULTS

Median follow-up was 218 days. For the fractionated stereotactic radiation therapy group, local control rates were 100% at 360 days and 64% at 720 days; for the stereotactic radiosurgery group, rates were 58% at 360 days and 48% at 720 days (P=0.06). Median survival time was 504 days for the fractionated stereotactic radiation therapy group and 164 days for the stereotactic radiosurgery group (P=0.049). Two cases of grade 2 toxicity were observed in the fractionated stereotactic radiation therapy group, and 6 cases of grade 1-2 toxicity, in the stereotactic radiosurgery group.

CONCLUSIONS

This study provides data to support that fractionated stereotactic radiation therapy without whole brain radiation therapy with a margin dose of 3 fractions of 7.7Gy for treatment of solitary large brain metastases is efficient and well-tolerated. Because of the significant improvement in overall survival, this schedule should be assessed in a randomized trial.

Salvage stereotactic radiosurgery for brain metastases

Recurrent or progressive brain metastases after initial treatment represent a common clinical entity mainly due to increased survival of cancer patients. From the various available treatment modalities, salvage stereotactic radiosurgery seems to be the most commonly used. Many clinical studies of class of evidence III have demonstrated satisfied results concerning the local brain control and survival of patients with relapsing brain disease. Also stereotactic radiosurgery is considered a relatively safe modality with low incidence of brain toxicity side effects. It is obvious that well-designed, randomized, prospective studies are necessary for the evaluation of the stereotactic radiosurgery as salvage treatment and for the establishment of guidelines for the selection of patients most suitable for this treatment option. The increasing number of patients with relapsing brain metastatic disease will act as a pressure to this direction.

Surgery of recurrent brain metastases: retrospective analysis of 67 patients

OBJECTIVE

Treatment of patients with recurrent brain metastasis is one of the major challenges in neurooncology. Commonly, WBRT was applied after or as the initial treatment. Many patients received radiosurgery or their lesions were operated on. The question arises of what treatment modalities are appropriate and can be offered to the patients. In our retrospective analysis, we evaluated whether re-operation might be a useful measurement for the patients with respect to overall survival and quality of life.

METHODS

We included 67 patients who were treated between 1993 and 2008 in our department. The median age was 59 years. Metastases of 11 different primaries were diagnosed. The median OST was 7.5 months.

RESULTS

Statistically significant prognostic factors for OS were single lesions, completeness of resection, and time to recurrence, which was significantly influenced by WBRT after first operation. The one year survival rate correlated with the RPA classification: class I: 53.3 %, class II: 26.9 %, class III: 12.5 %. In 31.3 %, a second recurrence occurred which was treated by repeated surgery. Six patients survived as long-term survivors (25.7-132.2 months).

CONCLUSION

Surgery of recurrent brain metastasis is an important therapeutic option. A subgroup of patients, defined by prognostic factors, will profit with improvement of symptoms and prolongation of the overall survival time. Even long-term survivors can be expected.

Population-based outcomes of boost versus salvage radiosurgery for brain metastases after whole brain radiotherapy

PURPOSE

We conducted a retrospective population-based study to examine the survival outcomes in patients with brain metastases treated with salvage stereotactic radiosurgery (SRS), compared to boost SRS, after previous whole brain radiotherapy (WBRT).

METHODS AND MATERIALS

From January 2000 to June 2011, 191 patients treated with WBRT and SRS for brain metastases in British Columbia were studied. Patients were divided into a boost cohort and a salvage cohort. The criteria used to determine eligibility for SRS were: 1-3 metastases, ≤4cm size, Karnofsky performance status ≥ 70, and control of extracranial disease.

RESULTS

Diagnosis by primary site was 84 lung, 47 breast, 15 melanoma, 12 renal, 9 colorectal, and 24 other. There were 113 patients (59%) in the boost cohort and 78 patients (41%) in the salvage cohort. The median overall survival from WBRT for the whole population was 17.7months: 12.1 months for the boost cohort and 22.7 months for the salvage cohort. There was no difference in median survival after SRS for the boost and salvage cohorts (11.2 vs. 11.2 months, p=0.78).

CONCLUSIONS

In selected patients with brain metastases treated with WBRT, survival following salvage SRS is as good as survival after WBRT + boost SRS.

The efficacy and limitations of stereotactic radiosurgery as a salvage treatment after failed whole brain radiotherapy for brain metastases

The aim of the present study was to evaluate the efficacy and limitations of repeat stereotactic radiosurgery (SRS) salvage for patients with recurrence of brain metastases (BM) after whole brain radiotherapy (WBRT). This is a retrospective, observational, single-center trial analyzing 77 consecutive patients with recurrent BM who were treated primarily with WBRT. All patients underwent SRS as salvage treatment. Median age was 62 years, and median Karnofsky performance status (KPS) was 80. The median interval between the starting date of WBRT and radiosurgery was 10.6 months. One, two and more than two SRS sessions were required in 42, 13 and 22 patients, respectively. The median total planning target volume (PTV) was 8.1 mL and the median dose prescribed was 20 Gy. The median follow-up was 7.7 months. 1- and 2-year neurological death-free survival (NS) rates were 87 and 78 %, respectively. Competing risk analysis demonstrated active extra-central nervous system (CNS) disease [Hazard ratio (HR) 0.236, P = 0.041] and total PTV on initial SRS (≥ 5 mL) (HR 4.22, P = 0.033) to be associated with the NS rate. 1- and 2-year overall survival (OS) rates were 41 and 11 %, respectively. The median OS time was 8.2 months. Active extra-CNS disease (HR 1.94, P = 0.034) and high KPS (≥ 90) (HR 0.409, P = 0.006) were associated with the OS rate. In total, 798 tumors (75 %) in 66 patients (86 %) with sufficient radiological follow-up data were evaluated. 1- and 2-year metastasis local control rates were 76.6 and 57.9 %, respectively. Prescribed dose (≥ 20 Gy) (HR 0.326, P < 0.001), tumor volume (≥ 2 mL) (HR 1.98, P = 0.007) and metastases from breast cancer (HR 0.435, P < 0.001) were independent predictive factors for local tumor control. Repeat salvage SRS for recurrent BM after WBRT appeared to be a safe and effective treatment. In the majority of patients, even those with numerous BM, neurological death could be delayed or even prevented.

Multiple gamma knife radiosurgery for multiple metachronous brain metastases associated with lung cancer : survival time

OBJECTIVE

We compared the survival time between patients with multiple gamma knife radiosurgery (GKRS) and patients with a single GKRS plus whole brain radiation therapy (WBRT), in patients with multiple metachronous brain metastases from lung cancer.

METHODS

From May 2006 to July 2010, we analyzed 31 patients out of 112 patients who showed multiple metachronous brain metastases. 20 out of 31 patients underwent multiple GKRS (group A) and 11 patients underwent a single GKRS plus WBRT (group B). We compared the survival time between group A and B. Kaplan-Meier method and Cox proportional hazards were used to analyze relationship between survival and 1) the number of lesions in each patient, 2) the average volume of lesions in each patient, 3) the number of repeated GKRS, and 4) the interval of development of new lesions, respectively.

RESULTS

Median survival time was 18 months (range 6-50 months) in group A and 6 months (range 3-18 months) in group B. Only the average volume of individual lesion (over 10 cc) was negatively related with survival time according to Kaplan-Meier method. Cox-proportional hazard ratio of each variable was 1.1559 for the number of lesions, 1.0005 for the average volume of lesions, 0.0894 for the numbers of repeated GKRS, and 0.5970 for the interval of development of new lesions.

CONCLUSION

This study showed extended survival time in group A compared with group B. Our result supports that multiple GKRS is of value in extending the survival time in patients with multiple metachronous brain metastases, and that the number of the lesions and the frequency of development of new lesions are not an obstacle in treating patients with GKRS.

ACR Appropriateness Criteria® follow-up and retreatment of brain metastases

Multiple options for retreatment are available, which include whole-brain radiation therapy, stereotactic radiosurgery, surgery, chemotherapy, and supportive care. Size, number, timing, location, histology, performance status, and extracranial disease status all need to be carefully considered when choosing a treatment modality. There are no randomized trials examining the retreatment of brain metastases. Repeat whole-brain radiation has been examined in a single-institution experience, showing the potential for clinical responses in selected patients. Local control rates as high as 91% using stereotactic radiosurgery for relapses after whole-brain radiation are reported. Surgery can be indicated in progressive and/or hemorrhagic lesions causing mass effect. The role of chemotherapy in the recurrent setting is limited but some agents may have activity on the basis of experiences on a smaller scale. Supportive care continues to be an important option, especially in those with a poor prognosis. Follow-up for brain metastases patients is discussed, examining the modality, frequency of imaging, and imaging options in differentiating treatment effect from recurrence. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of the current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Leptomeningeal seeding in patients with brain metastases treated by gamma knife radiosurgery

To characterize the development of leptomeningeal seeding (LMS) in patients with brain metastases after gamma knife radiosurgery (GKRS). Eight hundred and twenty-seven patients that underwent GKRS as a part of an initial treatment plan for brain metastases between January 2002 and December 2010 were included in the study. Six hundred and fifty patients were treated with GKRS alone and 177 patients received GKRS combined with upfront whole brain radiation therapy (WBRT). Actuarial curves for overall survival (OS) and the development of LMS were plotted using the Kaplan-Meier method. Median overall survival for all patients was 55 weeks (95 % CI, 47.8-62.2), and the overall incidence of LMS was 5.3 %. The actuarial rates for LMS at 6 and 12 months were 3.1 and 5.8, respectively. Uni- and multivariate analysis suggested that breast cancer and a large number of metastases (n ≥ 4) are significant risk factors of LMS (P < 0.05). Regarding treatment modalities, the addition of WBRT was found to have a significant impact on lowering the risk of LMS by multivariate analysis (P = 0.045). LMS is an important pattern of CNS failure. The risk of LMS following GKRS may be associated with multiple lesions, breast cancer, and the omission of WBRT. Additional data from large-scale, randomized controlled trials are required to identify risk factors associated with the LMS more accurately.

Chemotherapy as primary treatment for brain metastases from breast cancer: analysis of 115 one-year survivors

PURPOSE

Given the potential toxicity of whole brain radiotherapy, we introduced systemic therapy as possible primary treatment for brain metastases (BM) from breast cancer. This study aims to evaluate the feasibility of this therapeutic approach.

METHODS

Review of 115 breast cancer patients treated for BM with at least 1 year of follow-up.

RESULTS

Patients with single BM without extracranial disease were usually treated with surgery, patients with multiple BM and controlled extracranial disease usually with RT, and those with progressive extracranial disease usually with systemic therapy as primary treatment for BM. Primary treatment for BM was surgery in 30 patients, RT in 26 patients, RT combined with systemic therapy in 33 patients, and systemic therapy as single treatment in 27 patients (chemotherapy n = 20; hormonal therapy n = 7). Response rate to surgery was 100 %, to RT 85 %, to RT+systemic therapy 87 %, to chemotherapy 70 %, and to hormonal therapy 14 %. Duration of neurological response and of extracranial response to chemotherapy as single treatment was similar (8 and 7 months, respectively). Patients with single BM and patients without extracranial disease had a better survival but the difference was not significant.

CONCLUSION

Chemotherapy as single treatment for BM from breast cancer is feasible and should not be restricted to salvage treatment.

Management of melanoma brain metastases in the era of targeted therapy

Disseminated metastatic disease, including brain metastases, is commonly encountered in malignant melanoma. The classical treatment approach for melanoma brain metastases has been neurosurgical resection followed by whole brain radiotherapy. Traditionally, if lesions were either too numerous or surgical intervention would cause substantial neurologic deficits, patients were either treated with whole brain radiotherapy or referred to hospice and supportive care. Chemotherapy has not proven effective in treating brain metastases. Improvements in surgery, radiosurgery, and new drug discoveries have provided a wider range of treatment options. Additionally, recently discovered mutations in the melanoma genome have led to the development of "targeted therapy." These vastly improved options are resulting in novel treatment paradigms for approaching melanoma brain metastases in patients with and without systemic metastatic disease. It is therefore likely that improved survival can currently be achieved in at least a subset of melanoma patients with brain metastases.

Current standards in the management of cerebral metastases

The last 30 years have seen major changes in attitude toward patients with cerebral metastases. This paper aims to outline the major landmarks in this transition and the therapeutic strategies currently used. The controversies surrounding control of brain disease are discussed, and two emerging management trends are reviewed: tumor bed radiosurgery and salvage radiation.

T1/T2 matching to differentiate tumor growth from radiation effects after stereotactic radiosurgery

OBJECTIVE

We define magnetic resonance imaging (MRI) and clinical criteria that differentiate radiation effect (RE) from tumor progression after stereotactic radiosurgery (SRS).

METHODS

We correlated postoperative imaging and histopathological data in 68 patients who underwent delayed resection of a brain metastasis after SRS. Surgical resection was required in these patients because of clinical and imaging evidence of lesion progression 0.3 to 27.7 months after SRS. At the time of SRS, the median target volume was 7.1 mL (range, 0.5-26 mL), which increased to 14 mL (range, 1.3-81 mL) at the time of surgery. After initial SRS, routine contrast-enhanced MRI was used to assess tumor response and to detect potential adverse radiation effects. We retrospectively correlated these serial MRIs with the postoperative histopathology to determine if any routine MRI features might differentiate tumor progression from RE.

RESULTS

The median time from SRS to surgical resection was 6.9 months (range, 0.3-27.7 months). A shorter interval from SRS to resection was associated with a higher rate of tumor recurrence (P = .014). A correspondence between the contrast-enhanced volume on T1-weighted images and the low signal-defined lesion margin on T2-weighted images ("T1/T2 match") was associated with tumor progression at histopathology (P < .0001). Lack of a clear and defined lesion margin on T2-weighted images compared to the margin of contrast uptake on T1-weighted images ("T1/T2 mismatch") was significantly associated with a higher rate of RE in pathological specimens (P < .0001). The sensitivity of the T1/T2 mismatch in identifying RE was 83.3%, and the specificity was 91.1%.

CONCLUSIONS

We found that time to progression and T1/T2 mismatch were able to differentiate tumor progression from RE in most patients. When REs are suspected, surgery may not be necessary if patients respond to conservative measures. When tumor progression is suspected, resection or repeat radiosurgery can be effective, depending on the degree of mass effect.

The role of retreatment in the management of recurrent/progressive brain metastases: a systematic review and evidence-based clinical practice guideline

QUESTION

What evidence is available regarding the use of whole brain radiation therapy (WBRT), stereotactic radiosurgery (SRS), surgical resection or chemotherapy for the treatment of recurrent/progressive brain metastases?

TARGET POPULATION

This recommendation applies to adults with recurrent/progressive brain metastases who have previously been treated with WBRT, surgical resection and/or radiosurgery. Recurrent/progressive brain metastases are defined as metastases that recur/progress anywhere in the brain (original and/or non-original sites) after initial therapy.

RECOMMENDATION

Level 3 Since there is insufficient evidence to make definitive treatment recommendations in patients with recurrent/progressive brain metastases, treatment should be individualized based on a patient's functional status, extent of disease, volume/number of metastases, recurrence or progression at original versus non-original site, previous treatment and type of primary cancer, and enrollment in clinical trials is encouraged. In this context, the following can be recommended depending on a patient's specific condition: no further treatment (supportive care), re-irradiation (either WBRT and/or SRS), surgical excision or, to a lesser extent, chemotherapy. Question If WBRT is used in the setting of recurrent/progressive brain metastases, what impact does tumor histopathology have on treatment outcomes? No studies were identified that met the eligibility criteria for this question.

The results of resection after stereotactic radiosurgery for brain metastases

Object

Radiosurgery for brain metastasis fails in some patients, who require further surgical care. In this paper the authors' goal was to evaluate prognostic factors that correlate with the survival of patients who require a resection of a brain metastasis after stereotactic radiosurgery (SRS).

Methods

During the last 14 years when surgical navigation systems were routinely available, the authors identified 58 patients who required resection for various brain metastases after SRS. The median patient age was 54 years. Prior adjuvant treatment included whole-brain radiation therapy alone (17 patients), chemotherapy alone (9 patients), both radiotherapy and chemotherapy (10 patients), and prior resection before SRS (8 patients). The median target volumes at the time of SRS and resection were 7.7 cm3 (range 0.5–24.9 cm3) and 15.5 cm3 (range 1.3–81.2 cm3), respectively.

Results

At a median follow-up of 7.6 months, 8 patients (14%) were living and 50 patients (86%) had died. The survival after surgical removal was 65, 30, and 16% at 6, 12, and 24 months, respectively (median survival after resection 7.7 months). The local tumor control rate after resection was 71, 62, and 43% at 6, 12, and 24 months, respectively. A univariate analysis revealed that patient preoperative recursive partitioning analysis classification, Karnofsky Performance Scale status, systemic disease status, and the interval between SRS and resection were factors associated with patient survival. The mortality and morbidity rates of resection were 1.7 and 6.9%, respectively.

Conclusions

In patients with symptomatic mass effect after radiosurgery, resection may be warranted. Patients who had delayed local progression after SRS (> 3 months) had the best outcomes after resection.

Relationship between volume, dose and local control in stereotactic radiosurgery of brain metastasis

The aim of this study is to analyse the efficacy of linear accelerator stereotactic radiosurgery (SRS) on prognostic factors, local control rate and survival in patients with brain metastasis. Patients with either a single metastasis or up to 4 multiple brain metastases with a maximum tumour diameter of 40 mm for each tumour and a Karnofsky Performance Status (KPS) > or = 70 were eligible for SRS. SRS was applied to 150 lesions in 86 consecutive patients with a median age of 60 years (median 1 and mean 1.7 lesions per patient, mean KPS 86). Median overall survival was 6.2 months after SRS and 9.7 months from diagnosis of brain metastasis. Multivariate analysis revealed that a KPS of 90 or more (p = 0.009) and female sex (p = 0.003) were associated with a longer survival. Radiation dose < or = 15 Gy (p = 0.017) and KPS < 90 (p = 0.013) were independent predictors of a shorter time to local failure. Five patients showed evidence of radionecrosis with a median survival of 14.8 months. Addition of WBRT neither led to improvement of survival nor to improvement of local control. Improved local control following SRS for brain metastases was associated with KPS > or =90, a radiation dose > 15 Gy and a PTV < 13 cc. The potential of hypofractionated stereotactic radiotherapy (SRT) for brain metastases of larger volume warrants further study.

Treatment of brain metastases in patients with HER2+ breast cancer

Brain metastases are a frequent complication of cancer. However, effective treatments are available. This article aims to review clinical aspects of patients with brain metastases discussing the various treatment options for such patients. It will address the importance and significance of brain metastases in patients with breast cancer and, finally, review the problem of brain metastasis associated with human epidermal growth factor receptor 2-positive (HER2+) breast cancer. With ever-improving survival rates of patients with cancer, there is a greater likelihood that many will develop brain metastases. Treatments such as whole brain or stereotactic radiotherapy and surgery have been shown to be effective against brain metastases. In HER2+ breast cancer, trastuzumab has been shown to be very effective, although it cannot cross the blood-brain barrier. If patients with breast cancer who are being treated with trastuzumab and are responding systemically, develop brain metastases, then patient prognosis does need to be taken into account; however, maintaining treatment with trastuzumab while using available therapies to treat intracranial lesions should be considered as an option.

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.

Salvage stereotactic radiosurgery effectively treats recurrences from whole-brain radiation therapy

BACKGROUND

The purpose of the current study was to examine overall survival (OS) and time to local failure (LF) in patients who received salvage stereotactic radiosurgery (SRS) for recurrent brain metastases (BM) after initial management that included whole-brain radiation therapy (WBRT).

METHODS

The records of 1789 BM patients from August 1989 to November 2004 were reviewed. Of these, 111 underwent WBRT as part of their initial management and SRS as salvage. Patients were stratified by Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis class, primary disease, dimension of the largest metastases and number of BM at initial diagnosis, and time to first brain recurrence after WBRT. Overall survival, survival after SRS, and time to local and distant failure were analyzed.

RESULTS

The median OS from the initial diagnosis of BM was 17.7 months. Median survival after salvage SRS for the entire cohort was 9.9 months. Median survival after salvage SRS was 12.3 months in patients who had their first recurrence >6 months after WBRT versus 6.8 months for those who developed disease recurrence < or = 6 months after (P = .0061). Primary tumor site did not appear to affect survival after SRS. Twenty-eight patients (25%) developed local recurrence after their first SRS with a median time of 5.2 months. A dose <22 grays and lesion size >2 cm were found to be predictive of local failure.

CONCLUSIONS

In this study, patients who recurred after WBRT and were treated with salvage SRS were found to have good local control and survival after SRS. WBRT provided good initial control, as 45% of these patients failed >6 months after WBRT. Those with a longer time to failure after WBRT had significantly longer survival after SRS.

Multidisciplinary management of brain metastases

Metastatic brain tumors are the most common intracranial neoplasms in adults. The incidence of brain metastases appears to be rising as a result of superior imaging modalities, earlier detection, and more effective treatment of systemic disease. Therapeutic approaches to brain metastases include surgery, whole brain radiotherapy (WBRT), stereotactic radiosurgery (SRS), and chemotherapy. Treatment decisions must take into account clinical prognostic factors in order to maximize survival and neurologic function whilst avoiding unnecessary treatments. The goal of this article is to review important prognostic factors that may guide treatment selection, discuss the roles of surgery, radiation, and chemotherapy in the treatment of patients with brain metastases, and present new directions in brain metastasis therapy under active investigation. In the future, patients will benefit from a multidisciplinary approach focused on the integration of surgical, radiation, and chemotherapeutic options with the goal of prolonging survival, preserving neurologic and neurocognitive function, and maximizing quality of life.

Outcome After Radiosurgery for Brain Metastases in Patients With Low Karnofsky Performance Scale (KPS) Scores

PURPOSE

The objective of this retrospective study was evaluation of the outcome after stereotactic radiosurgery (SRS) in patients with intracranial metastases and poor performance status.

METHODS AND MATERIALS

Forty consecutive patients with metastatic brain tumors and Karnofsky performance scale (KPS) scores < or =50 (mean, 43 +/- 8; median, 40) treated with SRS were analyzed. Poor performance status was caused by presence of intracranial metastases in 28 cases (70%) and resulted from uncontrolled extracerebral disease in 12 (30%).

RESULTS

Survival after SRS varied from 3 days to 11.5 months (mean, 3.8 +/- 2.9 months; median, 3.3 months). Survival probability constituted 0.50 +/- 0.07 at 3 months and 0.20 +/- 0.05 at 6 months posttreatment. Cause of low KPS score (p = 0.0173) and presence of distant metastases beside the brain (p = 0.0308) showed statistically significant associations with overall survival in multivariate Cox proportional hazards regression analysis. Median survival was 6.0 months if low KPS score was caused by cerebral disease and distant metastases in regions beyond the brain were absent, 3.3 months if low KPS score was caused by cerebral disease and distant metastases in regions beyond the brain were present, and 1.0 month if poor performance status resulted from extracerebral disease.

CONCLUSIONS

Identification of the cause of low KPS score (cerebral vs. extracerebral) in patients with metastatic brain tumor(s) may be important for prediction of the outcome after radiosurgical treatment. If poor patient performance status without surgical indications is caused by intracranial tumor(s), SRS may be a reasonable treatment option.