Single-Fraction Versus Fractionated Preoperative Radiosurgery for Resected Brain Metastases: A PROPS-BM International Multicenter Cohort Study

PURPOSE

Preoperative stereotactic radiosurgery (SRS) is a feasible alternative to postoperative SRS for resected brain metastases (BM). Most reported studies of preoperative SRS used single-fraction SRS (SF-SRS). The goal of this study was to compare outcomes and toxicity of preoperative SF-SRS with multifraction (3-5 fractions) SRS (MF-SRS) in a large international multicenter cohort (Preoperative Radiosurgery for Brain Metastases-PROPS-BM).

METHODS AND MATERIALS

Patients with BM from solid cancers, of which at least 1 lesion was treated with preoperative SRS followed by planned resection, were included from 8 institutions. SRS to synchronous intact BM was allowed. Exclusion criteria included prior or planned whole brain radiation therapy. Intracranial outcomes were estimated using cumulative incidence with competing risk of death. Propensity score matched (PSM) analyses were performed.

RESULTS

The study cohort included 404 patients with 416 resected index lesions, of which SF-SRS and MF-SRS were used for 317 (78.5%) and 87 patients (21.5%), respectively. Median dose was 15 Gy in 1 fraction for SF-SRS and 24 Gy in 3 fractions for MF-SRS. Univariable analysis demonstrated that SF-SRS was associated with higher cavity local recurrence (LR) compared with MF-SRS (2-year: 16.3% vs 2.9%; P = .004), which was also demonstrated in multivariable analysis. PSM yielded 81 matched pairs (n = 162). PSM analysis also demonstrated significantly higher rate of cavity LR with SF-SRS (2-year: 19.8% vs 3.3%; P = .003). There was no difference in adverse radiation effect, meningeal disease, or overall survival between cohorts in either analysis.

CONCLUSIONS

Preoperative MF-SRS was associated with significantly reduced risk of cavity LR in both the unmatched and PSM analyses. There was no difference in adverse radiation effect, meningeal disease, or overall survival based on fractionation. MF-SRS may be a preferred option for neoadjuvant radiation therapy of resected BMs. Additional confirmatory studies are needed. A phase 3 randomized trial of single-fraction preoperative versus postoperative SRS (NRG-BN012) is ongoing (NCT05438212).

Prospective Phase II Trial of Primary Lung Tumor Stereotactic Body Radiation Therapy (SBRT) Followed By Concurrent Mediastinal Chemoradiation and Adjuvant Immunotherapy for Locally-Advanced Non-Small Cell Lung Cancer (LA NSCLC)

PURPOSE/OBJECTIVE(S)

To report the efficacy and toxicity outcomes of a prospective phase II trial of primary tumor SBRT followed by conventional chemoradiation to the lymph nodes and adjuvant immunotherapy in patients (pts) with unresectable LA NSCLC.

MATERIALS/METHODS

Eligible pts included stage II-III LA NSCLC with peripheral primary tumors ≤ 7cm or centrally based tumors that had at least 2 cm separation from involved nodal disease. Pts received SBRT to the primary tumor (50-54 Gy in 3-5 fractions) followed by standard radiation to 60 Gy in 30 fractions to the involved lymph nodes with concurrent platinum doublet chemotherapy. The trial was amended to allow pts without disease progression after chemoradiation to receive adjuvant durvalumab per the PACIFIC trial. The primary endpoint was 1 year progression free survival (PFS), evaluated as a binary variable. Frequencies and proportions were used for reporting this primary endpoint, in addition to adverse events and patterns of failure. Median PFS and OS were estimated using Kaplan Meier methods.

RESULTS

Safety and efficacy is reported on the first 50 pts enrolled in the trial with a median follow-up of 24 months (mos) (range, 1-54 mos). Pts were primarily stage IIIA (60%) or stage IIIB (34%), with 6% of pts stage IIB. Overall grade 3 or higher toxicity related to SBRT and/or mediastinal radiation was 8% with two pts (4%) developing grade 3 pneumonitis and one pt having a grade 5 lung infection possibly related to radiation. Overall grade 2 pneumonitis related to SBRT or mediastinal radiation was 20%. Only one pt (2%) developed grade 3 esophagitis. No late cardiac events have been observed. The one-year PFS for all pts was 62% with a median PFS of 26.3 mos and median overall survival of 40.8 mos. Of the 50 pts enrolled, 37 received at least one dose of adjuvant durvalumab. The one-year PFS for pts who received at least one dose of durvalumab was 70.3% with a median PFS not yet reached in this group (median follow-up 24 mos). Patterns of failure were mostly distant with 26% of pts experiencing distant failure, 6% regional, and 2% distant and regional. There was only one local failure (2%) after SBRT in all 50 pts.

CONCLUSION

SBRT to the primary tumor followed by conventional chemoradiation to the involved lymph nodes and adjuvant immunotherapy was well tolerated and showed improved 1-year PFS compared to prior conventional chemoradiation trials for locally advanced NSCLC. The results of this trial will be further evaluated in a randomized phase III study, NRG LU-008. Pts will receive either conventional chemoradiation vs. SBRT to the primary tumor followed by chemoradiation to the involved lymph nodes followed by consolidative immunotherapy to evaluate the possibility of utilization of SBRT as a new standard of care for LA NSCLC.

Risk Factors for Progression and Toxic Effects After Preoperative Stereotactic Radiosurgery for Patients With Resected Brain Metastases

Importance

Preoperative stereotactic radiosurgery (SRS) has been demonstrated as a feasible alternative to postoperative SRS for resectable brain metastases (BMs) with potential benefits in adverse radiation effects (AREs) and meningeal disease (MD). However, mature large-cohort multicenter data are lacking.

Objective

To evaluate preoperative SRS outcomes and prognostic factors from a large international multicenter cohort (Preoperative Radiosurgery for Brain Metastases-PROPS-BM).

Design, Setting, and Participants

This multicenter cohort study included patients with BMs from solid cancers, of which at least 1 lesion received preoperative SRS and a planned resection, from 8 institutions. Radiosurgery to synchronous intact BMs was allowed. Exclusion criteria included prior or planned whole-brain radiotherapy and no cranial imaging follow-up. Patients were treated between 2005 and 2021, with most treated between 2017 and 2021.

Exposures

Preoperative SRS to a median dose to 15 Gy in 1 fraction or 24 Gy in 3 fractions delivered at a median (IQR) of 2 (1-4) days before resection.

Main Outcomes and Measures

The primary end points were cavity local recurrence (LR), MD, ARE, overall survival (OS), and multivariable analysis of prognostic factors associated with these outcomes.

Results

The study cohort included 404 patients (214 women [53%]; median [IQR] age, 60.6 [54.0-69.6] years) with 416 resected index lesions. The 2-year cavity LR rate was 13.7%. Systemic disease status, extent of resection, SRS fractionation, type of surgery (piecemeal vs en bloc), and primary tumor type were associated with cavity LR risk. The 2-year MD rate was 5.8%, with extent of resection, primary tumor type, and posterior fossa location being associated with MD risk. The 2-year any-grade ARE rate was 7.4%, with target margin expansion greater than 1 mm and melanoma primary being associated with ARE risk. Median OS was 17.2 months (95% CI, 14.1-21.3 months), with systemic disease status, extent of resection, and primary tumor type being the strongest prognostic factors associated with OS.

Conclusions and Relevance

In this cohort study, the rates of cavity LR, ARE, and MD after preoperative SRS were found to be notably low. Several tumor and treatment factors were identified that are associated with risk of cavity LR, ARE, MD, and OS after treatment with preoperative SRS. A phase 3 randomized clinical trial of preoperative vs postoperative SRS (NRG BN012) has began enrolling (NCT05438212).

Immune niches in brain metastases contain TCF1+ stem-like T cells, are associated with disease control and are modulated by preoperative SRS

The CD8+ T-cell response is prognostic for survival outcomes in several tumor types. However, whether this extends to tumors in the brain, an organ with barriers to T cell entry, remains unclear. Here, we analyzed immune infiltration in 67 brain metastasis (BrM) and found high frequencies of PD1+ TCF1+ stem-like CD8+ T-cells and TCF1- effector-like cells. Importantly, the stem-like cells aggregate with antigen presenting cells in immune niches, and niches were prognostic for local disease control. Standard of care for BrM is resection followed by stereotactic radiosurgery (SRS), so to determine SRS's impact on the BrM immune response, we examined 76 BrM treated with pre-operative SRS (pSRS). pSRS acutely reduced CD8+ T cells at 3 days. However, CD8+ T cells rebounded by day 6, driven by increased frequency of effector-like cells. This suggests that the immune response in BrM can be regenerated rapidly, likely by the local TCF1+ stem-like population.

Preoperative stereotactic radiosurgery in the management of brain metastases and gliomas

Stereotactic radiosurgery (SRS) is the delivery of a high dose ionizing radiation in a highly conformal manner, which allows for significant sparing of nearby healthy tissues. It is typically delivered in 1-5 sessions and has demonstrated safety and efficacy across multiple intracranial neoplasms and functional disorders. In the setting of brain metastases, postoperative and definitive SRS has demonstrated favorable rates of tumor control and improved cognitive preservation compared to conventional whole brain radiation therapy. However, the risk of local failure and treatment-related complications (e.g. radiation necrosis) markedly increases with larger postoperative treatment volumes. Additionally, the risk of leptomeningeal disease is significantly higher in patients treated with postoperative SRS. In the setting of high grade glioma, preclinical reports have suggested that preoperative SRS may enhance anti-tumor immunity as compared to postoperative radiotherapy. In addition to potentially permitting smaller target volumes, tissue analysis may permit characterization of DNA repair pathways and tumor microenvironment changes in response to SRS, which may be used to further tailor therapy and identify novel therapeutic targets. Building on the work from preoperative SRS for brain metastases and preclinical work for high grade gliomas, further exploration of this treatment paradigm in the latter is warranted. Presently, there are prospective early phase clinical trials underway investigating the role of preoperative SRS in the management of high grade gliomas. In the forthcoming sections, we review the biologic rationale for preoperative SRS, as well as pertinent preclinical and clinical data, including ongoing and planned prospective clinical trials.

Radiation Therapy for Brain Metastases: An ASTRO Clinical Practice Guideline

PURPOSE

This guideline provides updated evidence-based recommendations addressing recent developments in the management of patients with brain metastases, including advanced radiation therapy techniques such as stereotactic radiosurgery (SRS) and hippocampal avoidance whole brain radiation therapy and the emergence of systemic therapies with central nervous system activity.

METHODS

The American Society for Radiation Oncology convened a task force to address 4 key questions focused on the radiotherapeutic management of intact and resected brain metastases from nonhematologic solid tumors. The guideline is based on a systematic review provided by the Agency for Healthcare Research and Quality. Recommendations were created using a predefined consensus-building methodology and system for grading evidence quality and recommendation strength.

RESULTS

Strong recommendations are made for SRS for patients with limited brain metastases and Eastern Cooperative Oncology Group performance status 0 to 2. Multidisciplinary discussion with neurosurgery is conditionally recommended to consider surgical resection for all tumors causing mass effect and/or that are greater than 4 cm. For patients with symptomatic brain metastases, upfront local therapy is strongly recommended. For patients with asymptomatic brain metastases eligible for central nervous system-active systemic therapy, multidisciplinary and patient-centered decision-making to determine whether local therapy may be safely deferred is conditionally recommended. For patients with resected brain metastases, SRS is strongly recommended to improve local control. For patients with favorable prognosis and brain metastases receiving whole brain radiation therapy, hippocampal avoidance and memantine are strongly recommended. For patients with poor prognosis, early introduction of palliative care for symptom management and caregiver support are strongly recommended.

CONCLUSIONS

The task force has proposed recommendations to inform best clinical practices on the use of radiation therapy for brain metastases with strong emphasis on multidisciplinary care.

Volumetric Modulated Arc Therapy (VMAT) Craniospinal Irradiation (CSI) for Children and Adults: A Practical Guide for Implementation

PURPOSE

Volumetric modulated arc therapy (VMAT) craniospinal irradiation (CSI) has been shown to have significant dosimetric advantages compared to 3D-conformal therapy, but is a technically complex process. We sought to develop a guide for all aspects of the VMAT CSI process and report patient dosimetry results.

METHODS AND MATERIALS

We initiated VMAT CSI in 2017 and have regularly revised our standard operating procedure (SOP) for this process since then. Herein, we report a detailed template for the entire VMAT CSI process from initial patient setup and immobilization at time of CT simulation to contouring and treatment planning, quality assurance, and therapy delivery. The records of 12 patients who were treated with VMAT CSI were also retrospectively reviewed.

RESULTS

Patient age ranged from 2 to 59 years with 5 pediatric patients (age<18 years), 5 young adults (age 18-35 years) and 2 older adults (age>35 years). The majority of patients (67%) had medulloblastoma. CSI dose ranged from 21.6 Gy to 36 Gy, with a median of 36 Gy. The median CSI planning target volume (PTV) was 2383cc with a median V95% of 99.8% and median 0.03 cc hotspot of 112.5%. The average V107% was 7.4% and the average conformality index was 1.01.

CONCLUSIONS

VMAT CSI has potentially significant dosimetric and acute toxicity advantages compared to 3D-conformal. However, proper procedures need to be in place throughout the process in order to be able to realize these potential advantages. We herein describe our detailed SOP for VMAT CSI. Recognizing the scarcity of proton beam centers in many areas, VMAT CSI represents a feasible treatment with more widespread availability.

Preoperative Radiosurgery for Resected Brain Metastases: The PROPS-BM Multicenter Cohort Study

PURPOSE

Preoperative radiosurgery (SRS) is a feasible alternative to postoperative SRS, with potential benefits in adverse radiation effect (ARE) and leptomeningeal disease (LMD) relapse. However, previous studies are limited by small patient numbers and single-institution designs. Our aim was to evaluate preoperative SRS outcomes and prognostic factors from a large multicenter cohort (Preoperative Radiosurgery for Brain Metastases [PROPS-BM]).

METHODS AND MATERIALS

Patients with brain metastases (BM) from solid cancers who had at least 1 lesion treated with preoperative SRS and underwent a planned resection were included from 5 institutions. SRS to synchronous intact BM was allowed. Radiographic meningeal disease (MD) was categorized as either nodular or classical "sugarcoating" (cLMD).

RESULTS

The cohort included 242 patients with 253 index lesions. Most patients (62.4%) had a single BM, 93.7% underwent gross total resection, and 98.8% were treated with a single fraction to a median dose of 15 Gray to a median gross tumor volume of 9.9 cc. Cavity local recurrence (LR) rates at 1 and 2 years were 15% and 17.9%, respectively. Subtotal resection (STR) was a strong independent predictor of LR (hazard ratio, 9.1; P < .001). One and 2-year rates of MD were 6.1% and 7.6% and of any grade ARE were 4.7% and 6.8% , respectively. The median overall survival (OS) duration was 16.9 months and the 2-year OS rate was 38.4%. The majority of MD was cLMD (13 of 19 patients with MD; 68.4%). Of 242 patients, 10 (4.1%) experienced grade ≥3 postoperative surgical complications.

CONCLUSIONS

To our knowledge, this multicenter study represents the largest cohort treated with preoperative SRS. The favorable outcomes previously demonstrated in single-institution studies, particularly the low rates of MD and ARE, are confirmed in this expanded multicenter analysis, without evidence of an excessive postoperative surgical complication risk. STR, though infrequent, is associated with significantly worse cavity LR. A randomized trial between preoperative and postoperative SRS is warranted and is currently being designed.

The Association Between Radiation Therapy Dose and Overall Survival in Patients With Intracranial Infiltrative Low-Grade Glioma Treated With Concurrent and/or Adjuvant Chemotherapy

Purpose

Previous trials have shown no benefit for radiation therapy (RT) dose escalation when RT is given as adjuvant monotherapy for infiltrative low-grade glioma (LGG). However, the current standard of care for high-risk LGG is RT with concurrent and/or adjuvant chemotherapy. The effect of RT dose escalation on overall survival (OS) in the setting of concurrent and/or adjuvant chemotherapy is not well established.

Methods and Materials

We used the National Cancer Database to select records for adult patients with intracranial grade 2 LGG diagnosed between 2004 and 2015. Patients must have received adjuvant external beam RT with concurrent and/or adjuvant chemotherapy. RT dose level was categorized as standard (45-54 Gy) or high (>54-65 Gy). Multivariable and propensity score matched analyses were used.

Results

The study cohort consisted of 1043 patients, of whom 644 (62%) received standard dose (median, 54 Gy) and 399 (38%) received high-dose RT (median, 60 Gy). RT dose level was not associated with OS (hazard ratio, 1.2; P = .1) in multivariable analysis. Propensity score matching yielded 380 matched pairs (n = 760). There was no difference in OS for high-dose versus standard-dose RT in the matched cohort (5-year OS 64% vs 69%; P = .14) or in the 2 prespecified subgroups of astrocytoma histology and 1p/19q noncodeleted.

Conclusions

Adjuvant RT dose escalation above 54 Gy in the setting of concurrent and/or adjuvant chemotherapy was not associated with improved OS for patients with infiltrative LGG in this National Cancer Database retrospective study. This was also true for the subgroups with less chemotherapy-sensitive disease, including astrocytoma histology and 1p/19q noncodeleted, although these analyses were limited by small size. Methods to improve OS other than RT dose escalation in the setting of concurrent and/or adjuvant chemotherapy should be considered for patients with poor-prognosis LGG.

Implementation, adherence, and results of systematic SARS-CoV-2 testing for asymptomatic patients treated at a tertiary care regional radiation oncology network

Background

Coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 virus is a current pandemic. We initiated a program of systematic SARS-CoV-2 polymerase chain reaction (PCR) testing in all asymptomatic patients receiving radiotherapy (RT) at a large radiation oncology network in the Charlotte, NC metropolitan region and report adherence and results of the testing program.

Methods

Patients undergoing simulation for RT between May 18, 2020 and July 10, 2020 within the Levine Cancer Institute radiation oncology network who were asymptomatic for COVID-19 associated symptoms, without previous positive SARS-CoV-2 testing, and without recent high-risk contacts were included. PCR testing was performed on nasal cavity or nasopharyngeal swab samples. Testing was performed within 2 weeks of RT start (pre-RT) and at least every 4 weeks during RT for patients with prolonged RT courses (intra-RT). An automated task based process using the oncology electronic medical record (EMR) was developed specifically for this purpose.

Results

A total of 604 unique patients were included in the cohort. Details on testing workflow and implementation are described herein. Pre-RT PCR testing was performed in 573 (94.9%) patients, of which 4 (0.7%) were positive. The adherence rate to intra-RT testing overall was 91.6%. Four additional patients (0.7%) tested positive during their RT course, of whom 3 were tested due to symptom development and 1 was asymptomatic and identified via systematic testing. A total of 8 (1.3%) patients tested positive overall. There were no known cases of SARS-CoV-2 transmission from infected patients to clinic staff and/or other patients.

Conclusions

We detailed the workflows used to implement systematic SARS-CoV-2 for asymptomatic patients at a large radiation oncology network. Adherence rates for pre-RT and intra-RT testing were high using this process. This information allowed for appropriate delay in initiating RT, minimizing the occurrence of RT treatment interruptions, and no known cases of transmission from infected patients to clinic staff and/or other patients.

The effect of adjuvant radiotherapy on overall survival in adults with intracranial ependymoma

BACKGROUND

Adult intracranial ependymoma is rare, and the role for adjuvant radiotherapy (RT) is not well defined.

METHODS

We used the National Cancer Database (NCDB) to select adults (age ≥ 22 years) with grade 2 to 3 intracranial ependymoma status postresection between 2004 and 2015 and treated with adjuvant RT vs observation. Four cohorts were generated: (1) all patients, (2) grade 2 only, (3) grade 2 status post-subtotal resection only, (4) and grade 3 only. The association between adjuvant RT use and overall survival (OS) was assessed using multivariate Cox and propensity score matched analyses.

RESULTS

A total of 1787 patients were included in cohort 1, of which 856 patients (48%) received adjuvant RT and 931 (52%) were observed. Approximately two-thirds of tumors were supratentorial and 80% were grade 2. Cohorts 2, 3, and 4 included 1471, 345, and 316 patients, respectively. There was no significant association between adjuvant RT use and OS in multivariate or propensity score matched analysis in any of the cohorts. Older age, male sex, urban location, higher comorbidity score, earlier year of diagnosis, and grade 3 were associated with increased risk of death.

CONCLUSIONS

This large NCDB study did not demonstrate a significant association between adjuvant RT use and OS for adults with intracranial ependymoma, including for patients with grade 2 ependymoma status post-subtotal resection. The conflicting results regarding the efficacy of adjuvant RT in this patient population highlight the need for high-quality studies to guide therapy recommendations in adult ependymoma.

Use of surface-guided radiation therapy in combination with IGRT for setup and intrafraction motion monitoring during stereotactic body radiation therapy treatments of the lung and abdomen

Background and purpose

Multiple techniques can be used to assist with more accurate patient setup and monitoring during Stereotactic body radiation therapy (SBRT) treatment. This study analyzes the accuracy of 3D surface mapping with Surface‐guided radiation therapy (SGRT) in detecting interfraction setup error and intrafraction motion during SBRT treatments of the lung and abdomen.

Materials and Methods

Seventy‐one patients with 85 malignant thoracic or abdominal tumors treated with SBRT were analyzed. For initial patient setup, an alternating scheme of kV/kV imaging or SGRT was followed by cone beam computed tomography (CBCT) for more accurate tumor volumetric localization. The CBCT six degree shifts after initial setup with each method were recorded to assess interfraction setup error. Patients were then monitored continuously with SGRT during treatment. If an intrafractional shift in any direction >2 mm for longer than 2 sec was detected by SGRT, then CBCT was repeated and the recorded deltas were compared to those detected by SGRT.

Results

Interfractional shifts after SGRT setup and CBCT were small in all directions with mean values of <5 mm and < 0.5 degrees in all directions. Additionally, 25 patients had detected intrafraction motion by SGRT during a total of 34 fractions. This resulted in 25 (73.5%) additional shifts of at least 2 mm on subsequent CBCT. When comparing the average vector detected shift by SGRT to the resulting vector shift on subsequent CBCT, no significant difference was found between the two.

Conclusions

Surface‐guided radiation therapy provides initial setup within 5 mm for patients treated with SBRT and can be used in place of skin marks or planar kV imaging prior to CBCT. In addition, continuous monitoring with SGRT during treatment was valuable in detecting potentially clinically meaningful intrafraction motion and was comparable in magnitude to shifts from additional CBCT scans. PTV margin reduction may be feasible for SBRT in the lung and abdomen when using SGRT for continuous patient monitoring during treatment.

Nodular Leptomeningeal Disease-A Distinct Pattern of Recurrence After Postresection Stereotactic Radiosurgery for Brain Metastases: A Multi-institutional Study of Interobserver Reliability

PURPOSE

For brain metastases, surgical resection with postoperative stereotactic radiosurgery is an emerging standard of care. Postoperative cavity stereotactic radiosurgery is associated with a specific, underrecognized pattern of intracranial recurrence, herein termed nodular leptomeningeal disease (nLMD), which is distinct from classical leptomeningeal disease. We hypothesized that there is poor consensus regarding the definition of LMD, and that a formal, self-guided training module will improve interrater reliability (IRR) and validity in diagnosing LMD.

METHODS AND MATERIALS

Twenty-two physicians at 16 institutions, including 15 physicians with central nervous system expertise, completed a 2-phase survey that included magnetic resonance imaging and treatment information for 30 patients. In the "pretraining" phase, physicians labeled cases using 3 patterns of recurrence commonly reported in prospective studies: local recurrence (LR), distant parenchymal recurrence (DR), and LMD. After a self-directed training module, participating physicians completed the "posttraining" phase and relabeled the 30 cases using the 4 following labels: LR, DR, classical leptomeningeal disease, and nLMD.

RESULTS

IRR increased 34% after training (Fleiss' Kappa K = 0.41 to K = 0.55, P < .001). IRR increased most among non-central nervous system specialists (+58%, P < .001). Before training, IRR was lowest for LMD (K = 0.33). After training, IRR increased across all recurrence subgroups and increased most for LMD (+67%). After training, ≥27% of cases initially labeled LR or DR were later recognized as nLMD.

CONCLUSIONS

This study highlights the large degree of inconsistency among clinicians in recognizing nLMD. Our findings demonstrate that a brief self-guided training module distinguishing nLMD can significantly improve IRR across all patterns of recurrence, and particularly in nLMD. To optimize outcomes reporting, prospective trials in brain metastases should incorporate central imaging review and investigator training.

A multi-institutional analysis of presentation and outcomes for leptomeningeal disease recurrence after surgical resection and radiosurgery for brain metastases

BACKGROUND

Radiographic leptomeningeal disease (LMD) develops in up to 30% of patients following postoperative stereotactic radiosurgery (SRS) for brain metastases. However, the clinical relevancy of this finding and outcomes after various salvage treatments are not known.

METHODS

Patients with brain metastases, of which 1 was resected and treated with adjunctive SRS, and who subsequently developed LMD were combined from 7 tertiary care centers. LMD pattern was categorized as nodular (nLMD) or classical ("sugarcoating," cLMD).

RESULTS

The study cohort was 147 patients. Most patients (60%) were symptomatic at LMD presentation, with cLMD more likely to be symptomatic than nLMD (71% vs. 51%, P = 0.01). Salvage therapy was whole brain radiotherapy (WBRT) alone (47%), SRS (27%), craniospinal radiotherapy (RT) (10%), and other (16%), with 58% receiving a WBRT-containing regimen. WBRT was associated with lower second LMD recurrence compared with focal RT (40% vs 68%, P = 0.02). Patients with nLMD had longer median overall survival (OS) than those with cLMD (8.2 vs 3.3 mo, P < 0.001). On multivariable analysis for OS, pattern of initial LMD (nodular vs classical) was significant, but type of salvage RT (WBRT vs focal) was not.

CONCLUSIONS

Nodular LMD is a distinct pattern of LMD associated with postoperative SRS that is less likely to be symptomatic and has better OS outcomes than classical "sugarcoating" LMD. Although focal RT demonstrated increased second LMD recurrence compared with WBRT, there was no associated OS detriment. Focal cranial RT for nLMD recurrence after surgery and SRS for brain metastases may be a reasonable alternative to WBRT.

Preoperative stereotactic radiosurgery before planned resection of brain metastases: updated analysis of efficacy and toxicity of a novel treatment paradigm

OBJECTIVEPreoperative stereotactic radiosurgery (SRS) is a feasible alternative to postoperative SRS and may lower the risk of radiation necrosis (RN) and leptomeningeal disease (LMD) recurrence. The study goal was to report the efficacy and toxicity of preoperative SRS in an expanded patient cohort with longer follow-up period relative to prior reports.METHODSThe records for patients with brain metastases treated with preoperative SRS and planned resection were reviewed. Patients with classically radiosensitive tumors, planned adjuvant whole brain radiotherapy, or no cranial imaging at least 1 month after surgery were excluded. Preoperative SRS dose was based on lesion size and was reduced approximately 10-20% from standard dosing. Surgery generally followed within 48 hours.RESULTSThe study cohort consisted of 117 patients with 125 lesions treated with single-fraction preoperative SRS and planned resection. Of the 117 patients, 24 patients were enrolled in an initial prospective trial; the remaining 93 cases were consecutively treated patients who were retrospectively reviewed. Most patients had a single brain metastasis (70.1%); 42.7% had non-small cell lung cancer, 18.8% had breast cancer, 15.4% had melanoma, and 11.1% had renal cell carcinoma. Gross total resection was performed in 95.2% of lesions. The median time from SRS to surgery was 2 days, the median SRS dose was 15 Gy, and the median gross tumor volume was 8.3 cm3. Event cumulative incidence at 2 years was as follows: cavity local recurrence (LR), 25.1%; distant brain failure, 60.2%; LMD, 4.3%; and symptomatic RN, 4.8%. The median overall survival (OS) and 2-year OS rate were 17.2 months and 36.7%, respectively. Subtotal resection (STR, n = 6) was significantly associated with increased risk of cavity LR (hazard ratio [HR] 6.67, p = 0.008) and worsened OS (HR 2.63, p = 0.05) in multivariable analyses.CONCLUSIONSThis expanded and updated analysis confirms that single-fraction preoperative SRS confers excellent cavity local control with very low risk of RN or LMD. Preoperative SRS has several potential advantages compared to postoperative SRS, including reduced risk of RN due to smaller irradiated volume without need for cavity margin expansion and reduced risk of LMD due to sterilization of tumor cells prior to spillage at the time of surgery. Subtotal resection, though infrequent, is associated with significantly worse cavity LR and OS. Based on these results, a randomized trial of preoperative versus postoperative SRS is being designed.

The Evolving Role of Tumor Treating Fields in Managing Glioblastoma: Guide for Oncologists

Glioblastoma (GBM) is a devastating brain tumor with poor prognosis despite advances in surgery, radiation, and chemotherapy. Survival of patients with glioblastoma remains poor, with only 1 in 4 patients alive at 2 years, and a 5-year survival rate of about 5%. Recurrence is nearly universal and, after recurrence, prognosis is poor with very short progression-free survival and overall survival (OS). Various salvage chemotherapy strategies have been applied with limited success. Tumor Treating Fields (TTFields) are a novel treatment modality approved for treatment of either newly diagnosed or recurrent GBM. TTFields therapy involves a medical device and transducer arrays to provide targeted delivery of low intensity, intermediate frequency, alternating electric fields to produce antimitotic effects selective for rapidly dividing tumor cells with limited toxicity. In the phase 3 EF-14 trial, TTFields plus temozolomide provided significantly longer progression-free survival and OS compared with temozolomide alone in patients with newly diagnosed GBM after initial chemoradiotherapy. The addition of TTFields to standard therapy improved median OS from 15.6 to 20.5 months (P=0.04). In the phase 3 EF-11 trial, for recurrent GBM, TTFields provided comparable efficacy as investigator's choice systemic therapy, with improved patient-reported quality of life and a lower incidence of serious adverse events. Primary toxicity associated with TTFields is skin irritation generally managed with array relocation and topical treatments including antibiotics and steroids. TTFields therapy has demonstrated proven efficacy in management of GBM, including improvement in OS for patients with newly diagnosed GBM, and is under current investigation in other brain and extracranial tumors.

Comparing Preoperative With Postoperative Stereotactic Radiosurgery for Resectable Brain Metastases: A Multi-institutional Analysis

BACKGROUND

Stereotactic radiosurgery (SRS) is an increasingly common modality used with surgery for resectable brain metastases (BM).

OBJECTIVE

To present a multi-institutional retrospective comparison of outcomes and toxicities of preoperative SRS (Pre-SRS) and postoperative SRS (Post-SRS).

METHODS

We reviewed the records of patients who underwent resection of BM and either Pre-SRS or Post-SRS alone between 2005 and 2013 at 2 institutions. Pre-SRS used a dose-reduction strategy based on tumor size, with planned resection within 48 hours. Cumulative incidence with competing risks was used to determine estimated rates.

RESULTS

A total of 180 patients underwent surgical resection for 189 BM: 66 (36.7%) underwent Pre-SRS and 114 (63.3%) underwent Post-SRS. Baseline patient characteristics were balanced except for higher rates of performance status 0 (62.1% vs 28.9%, P < .001) and primary breast cancer (27.2% vs 10.5%, P = .010) for Pre-SRS. Pre-SRS had lower median planning target volume margin (0 mm vs 2 mm) and peripheral dose (14.5 Gy vs 18 Gy), but similar gross tumor volume (8.3 mL vs 9.2 mL, P = .85). The median imaging follow-up period was 24.6 months for alive patients. Multivariable analyses revealed no difference between groups for overall survival (P = .1), local recurrence (P = .24), and distant brain recurrence (P = .75). Post-SRS was associated with significantly higher rates of leptomeningeal disease (2 years: 16.6% vs 3.2%, P = .010) and symptomatic radiation necrosis (2 years: 16.4% vs 4.9%, P = .010).

CONCLUSION

Pre-SRS and Post-SRS for resected BM provide similarly favorable rates of local recurrence, distant brain recurrence, and overall survival, but with significantly lower rates of symptomatic radiation necrosis and leptomeningeal disease in the Pre-SRS cohort. A prospective clinical trial comparing these treatment approaches is warranted.

ABBREVIATIONS

BM, brain metastasesCI, confidence intervalCTV, clinical target volumeDBR, distant brain recurrenceGTV, gross tumor volumeLC, local controlLMD, leptomeningeal diseaseLR, local recurrenceMVA, multivariable analysisOS, overall survivalPost-SRS, postoperative stereotactic radiosurgeryPre-SRS, preoperative stereotactic radiosurgeryPTV, planning target volumeRN, radiation necrosisSRN, symptomatic radiation necrosisSRS, stereotactic radiosurgeryWBRT, whole-brain radiation therapy.

Single-Fraction Stereotactic Radiosurgery (SRS) Alone Versus Surgical Resection and SRS for Large Brain Metastases: A Multi-institutional Analysis

PURPOSE

Stereotactic radiosurgery (SRS) dose is limited by brain metastasis (BM) size. The study goal was to retrospectively determine whether there is a benefit for intracranial outcomes and overall survival (OS) for gross total resection with single-fraction SRS versus SRS alone for patients with large BMs.

METHODS AND MATERIALS

A large BM was defined as ≥4 cm³ (2 cm in diameter) prior to the study. We reviewed the records of consecutive patients treated with single-fraction SRS alone or surgery with preoperative or postoperative SRS between 2005 and 2013 from 2 institutions.

RESULTS

Overall, 213 patients with 223 treated large BMs were included; 66 BMs (30%) were treated with SRS alone and 157 (70%) with surgery and SRS (63 preoperatively and 94 postoperatively). The groups (SRS vs surgery and SRS) were well balanced except regarding lesion volume (median, 5.9 cm³ vs 9.6 cm³; P<.001), median number of BMs (1.5 vs 1, P=.002), median SRS dose (18 Gy vs 15 Gy, P<.001), and prior whole-brain radiation therapy (33% vs 5%, P<.001). The local recurrence (LR) rate was significantly lower with surgery and SRS (1-year LR rate, 36.7% vs 20.5%; P=.007). There was no difference in radiation necrosis (RN) by resection status, but there was a significantly increased RN rate with postoperative SRS versus with preoperative SRS and with SRS alone (1-year RN rate, 22.6% vs 5% and 12.3%, respectively; P<.001). OS was significantly higher with surgery and SRS (2-year OS rate, 38.9% vs 19.8%; P=.01). Both multivariate adjusted analyses and propensity score-matched analyses demonstrated similar results.

CONCLUSIONS

In this retrospective study, gross total resection with SRS was associated with significantly reduced LR compared with SRS alone for patients with large BMs. Postoperative SRS was associated with the highest rate of RN. Surgical resection with SRS may improve outcomes in patients with a limited number of large BMs compared with SRS alone. Further studies are warranted.

Comparing pre-operative stereotactic radiosurgery (SRS) to post-operative whole brain radiation therapy (WBRT) for resectable brain metastases: a multi-institutional analysis

Pre-operative stereotactic radiosurgery (pre-SRS) has been shown as a viable treatment option for resectable brain metastases (BM). The aim of this study is to compare oncologic outcomes and toxicities for pre-SRS and post-operative WBRT (post-WBRT) for resectable BM. We reviewed records of consecutive patients who underwent resection of BM and either pre-SRS or post-WBRT between 2005 and 2013 at two institutions. Overall survival (OS) was calculated using the Kaplan-Meier method. Cumulative incidence was used for intracranial outcomes. Multivariate analysis (MVA) was performed using the Cox and Fine and Gray models, respectively. Overall, 102 patients underwent surgical resection of BM; 66 patients with 71 lesions received pre-SRS while 36 patients with 42 cavities received post-WBRT. Baseline characteristics were similar except for the pre-SRS cohort having more single lesions (65.2% vs. 38.9%, p = 0.001) and smaller median lesion volume (8.3 cc vs. 15.3 cc, p = 0.006). 1-year OS was similar between cohorts (58% vs. 56%, respectively) (p = 0.43). Intracranial outcomes were also similar (2-year outcomes, pre-SRS vs. post-WBRT): local recurrence: 24.5% vs. 25% (p = 0.81), distant brain failure (DBF): 53.2% vs. 45% (p = 0.66), and leptomeningeal disease (LMD) recurrence: 3.5% vs. 9.0% (p = 0.66). On MVA, radiation cohort was not independently associated with OS or any intracranial outcome. Crude rates of symptomatic radiation necrosis were 5.6 and 0%, respectively. OS and intracranial outcomes were similar for patients treated with pre-SRS or post-WBRT for resected BM. Pre-SRS is a viable alternative to post-WBRT for resected BM. Further confirmatory studies with neuro-cognitive outcomes comparing these two treatment paradigms are needed.

Effect of Radiosurgery Alone vs Radiosurgery With Whole Brain Radiation Therapy on Cognitive Function in Patients With 1 to 3 Brain Metastases: A Randomized Clinical Trial

IMPORTANCE

Whole brain radiotherapy (WBRT) significantly improves tumor control in the brain after stereotactic radiosurgery (SRS), yet because of its association with cognitive decline, its role in the treatment of patients with brain metastases remains controversial.

OBJECTIVE

To determine whether there is less cognitive deterioration at 3 months after SRS alone vs SRS plus WBRT.

DESIGN, SETTING, AND PARTICIPANTS

At 34 institutions in North America, patients with 1 to 3 brain metastases were randomized to receive SRS or SRS plus WBRT between February 2002 and December 2013.

INTERVENTIONS

The WBRT dose schedule was 30 Gy in 12 fractions; the SRS dose was 18 to 22 Gy in the SRS plus WBRT group and 20 to 24 Gy for SRS alone.

MAIN OUTCOMES AND MEASURES

The primary end point was cognitive deterioration (decline >1 SD from baseline on at least 1 cognitive test at 3 months) in participants who completed the baseline and 3-month assessments. Secondary end points included time to intracranial failure, quality of life, functional independence, long-term cognitive status, and overall survival.

RESULTS

There were 213 randomized participants (SRS alone, n = 111; SRS plus WBRT, n = 102) with a mean age of 60.6 years (SD, 10.5 years); 103 (48%) were women. There was less cognitive deterioration at 3 months after SRS alone (40/63 patients [63.5%]) than when combined with WBRT (44/48 patients [91.7%]; difference, -28.2%; 90% CI, -41.9% to -14.4%; P < .001). Quality of life was higher at 3 months with SRS alone, including overall quality of life (mean change from baseline, -0.1 vs -12.0 points; mean difference, 11.9; 95% CI, 4.8-19.0 points; P = .001). Time to intracranial failure was significantly shorter for SRS alone compared with SRS plus WBRT (hazard ratio, 3.6; 95% CI, 2.2-5.9; P < .001). There was no significant difference in functional independence at 3 months between the treatment groups (mean change from baseline, -1.5 points for SRS alone vs -4.2 points for SRS plus WBRT; mean difference, 2.7 points; 95% CI, -2.0 to 7.4 points; P = .26). Median overall survival was 10.4 months for SRS alone and 7.4 months for SRS plus WBRT (hazard ratio, 1.02; 95% CI, 0.75-1.38; P = .92). For long-term survivors, the incidence of cognitive deterioration was less after SRS alone at 3 months (5/11 [45.5%] vs 16/17 [94.1%]; difference, -48.7%; 95% CI, -87.6% to -9.7%; P = .007) and at 12 months (6/10 [60%] vs 17/18 [94.4%]; difference, -34.4%; 95% CI, -74.4% to 5.5%; P = .04).

CONCLUSIONS AND RELEVANCE

Among patients with 1 to 3 brain metastases, the use of SRS alone, compared with SRS combined with WBRT, resulted in less cognitive deterioration at 3 months. In the absence of a difference in overall survival, these findings suggest that for patients with 1 to 3 brain metastases amenable to radiosurgery, SRS alone may be a preferred strategy.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00377156.

Novel radiotherapy approaches for lung cancer: combining radiation therapy with targeted and immunotherapies

Targeted therapies and immunotherapies have quickly become fixtures in the treatment armamentarium for metastatic non-small cell lung cancer (NSCLC). Targeted therapies directed against epidermal growth factor receptor (EGFR) mutations, anaplastic lymphoma kinase (ALK) translocations, and ROS-1 rearrangements have demonstrated improved progression free survival (PFS) and, in selected populations, improved overall survival (OS) compared with cytotoxic chemotherapy. Immunotherapies, including checkpoint inhibitor monoclonal antibodies against programmed death receptor 1 (PD-1) and programmed death ligand 1 (PD-L1), have now also demonstrated improved survival compared with chemotherapy. The use of these novel systemic agents in non-metastatic patient populations and in combination with radiation therapy is not well defined. As radiation therapy has become more effective and more conformal with fewer toxicities, it has increasingly been used in the oligometastatic or oligoprogression setting. This has allowed improvement in PFS and potentially OS, and in the oligoprogressive setting may overcome acquired drug resistance of a specific lesion(s) to allow patients to remain on their targeted therapies. Molecularly targeted therapies and immunotherapies for patients with metastatic NSCLC have demonstrated much success. Advances in radiation therapy and stereotactic body radiotherapy, radiation therapy have led to combination strategies with targeted therapies among patients with lung cancer. Radiation therapy has also been combined with immunotherapies predominantly in the metastatic setting. In the metastatic population, radiation therapy has the ability to provide durable local control and also augment the immune response of systemic agents, which may lead to an abscopal effect of immune-mediated tumor response in disease sites outside of the radiation field in select patients.

Polymeric drug delivery for the treatment of glioblastoma

Glioblastoma (GBM) remains an almost universally fatal diagnosis. The current therapeutic mainstay consists of maximal safe surgical resection followed by radiation therapy (RT) with concomitant temozolomide (TMZ), followed by monthly TMZ (the "Stupp regimen"). Several chemotherapeutic agents have been shown to have modest efficacy in the treatment of high-grade glioma (HGG), but blood-brain barrier impermeability remains a major delivery obstacle. Polymeric drug-delivery systems, developed to allow controlled local release of biologically active substances for a variety of conditions, can achieve high local concentrations of active agents while limiting systemic toxicities. Polymerically delivered carmustine (BCNU) wafers, placed on the surface of the tumor-resection cavity, can potentially provide immediate chemotherapy to residual tumor cells during the standard delay between surgery and chemoradiotherapy. BCNU wafer implantation as monochemotherapy (with RT) in newly diagnosed HGG has been investigated in 2 phase III studies that reported significant increases in median overall survival. A number of studies have investigated the tumoricidal synergies of combination chemotherapy with BCNU wafers in newly diagnosed or recurrent HGG, and a primary research focus has been the integration of BCNU wafers into multimodality therapy with the standard Stupp regimen. Overall, the results of these studies have been encouraging in terms of safety and efficacy. However, the data must be qualified by the nature of the studies conducted. Currently, there are no phase III studies of BCNU wafers with the standard Stupp regimen. We review the rationale, biochemistry, pharmacokinetics, and research history (including toxicity profile) of this modality.

Pathology concordance levels for meningioma classification and grading in NRG Oncology RTOG Trial 0539

BACKGROUND

With advances in the understanding of histopathology on outcome, accurate meningioma grading becomes critical and drives treatment selection. The 2000 and 2007 WHO schema greatly increased the proportion of grade II meningiomas. Although associations with progression-free survival (PFS) and overall survival (OS) have been independently validated, interobserver concordance has not been formally assessed.

METHODS

Once mature, NRG Oncology RTOG-0539 will report PFS and OS in variably treated low-, intermediate-, and high-risk cohorts. We address concordance of histopathologic assessment between enrolling institutions and central review, performed by a single pathologist (AP), who is also involved in developing current WHO criteria.

RESULTS

The trial included 170 evaluable patients, 2 of whom had 2 eligible pathology reviews from different surgeries, resulting in 172 cases for analysis. Upon central review, 76 cases were categorized as WHO grade I, 71 as grade II, and 25 as grade III. Concordance for tumor grade was 87.2%. Among patients with WHO grades I, II, and III meningioma, respective concordance rates were 93.0%, 87.8%, and 93.6% (P values < .0001). Moderate to substantial agreement was encountered for individual grading criteria and were highest for brain invasion, ≥20 mitoses/10 high-powered field [HPF], and spontaneous necrosis, and lowest for small cells, sheeting, and ≥4 mitoses/10 HPF. In comparison, published concordance for gliomas in clinical trials have ranged from 8%-74%.

CONCLUSION

Our data suggest that current meningioma classification and grading are at least as objective and reproducible as for gliomas. Nevertheless, reproducibility remains suboptimal. Further improvements may be anticipated with education and clarification of subjective criteria, although development of biomarkers may be the most promising strategy.

A new treatment paradigm: neoadjuvant radiosurgery before surgical resection of brain metastases with analysis of local tumor recurrence

PURPOSE

Resected brain metastases (BM) require radiation therapy to reduce local recurrence. Whole brain radiation therapy (WBRT) reduces recurrence, but with potential toxicity. Postoperative stereotactic radiosurgery (SRS) is a strategy without prospective data and problematic target delineation. SRS delivered in the preoperative setting (neoadjuvant, or NaSRS) allows clear target definition and reduction of intraoperative dissemination of tumor cells.

METHODS AND MATERIALS

Our treatment of resectable BM with NaSRS was begun in 2005. Subsequently, a prospective trial of NaSRS was undertaken. A total of 47 consecutively treated patients (23 database and 24 prospective trial) with a total of 51 lesions were reviewed. No statistical difference was observed between the 2 cohorts, and they were combined for analysis. The median follow-up time was 12 months (range, 1-58 months), and the median age was 57. A median of 1 day elapsed between NaSRS and resection. The median diameter of lesions was 3.04 cm (range, 1.34-5.21 cm), and the median volume was 8.49 cc (range, 0.89-46.7 cc). A dose reduction strategy was used, with a median dose of 14 Gy (range, 11.6-18 Gy) prescribed to 80% isodose.

RESULTS

Kaplan-Meier overall survival was 77.8% and 60.0% at 6 and 12 months. Kaplan-Meier local control was 97.8%, 85.6%, and 71.8% at 6, 12, and 24 months, respectively. Five of 8 failures were proved pathologically without radiation necrosis. There were no perioperative adverse events. Ultimately, 14.8% of the patients were treated with WBRT. Local failure was more likely with lesions >10 cc (P=.01), >3.4 cm (P=.014), with a trend in surface lesions (P=.066) and eloquent areas (P=.052). Six of the 8 failures had an obvious dural attachment or proximity to draining veins.

CONCLUSIONS

NaSRS can be performed safely and effectively with excellent results without documented radiation necrosis. Local control was excellent even in the setting of large (>3 cm) lesions. The strong majority of patients were able to avoid WBRT. NaSRS merits consideration in a multi-institution trial.

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.

The role of emerging and investigational therapies for metastatic brain tumors: a systematic review and evidence-based clinical practice guideline of selected topics

QUESTION

What evidence is available regarding the emerging and investigational therapies for the treatment of metastatic brain tumors?

TARGET POPULATION

These recommendations apply to adults with brain metastases.

RECOMMENDATIONS

New radiation sensitizers Level 2 A subgroup analysis of a large prospective randomized controlled trial (RCT) suggested a prolongation of time to neurological progression with the early use of motexafin-gadolinium (MGd). Nonetheless this was not borne out in the overall study population and therefore an unequivocal recommendation to use the currently available radiation sensitizers, motexafin-gadolinium and efaproxiral (RSR 13) cannot be provided. Interstitial modalities There is no evidence to support the routine use of new or existing interstitial radiation, interstitial chemotherapy and or other interstitial modalities outside of approved clinical trials. New chemotherapeutic agents Level 2 Treatment of melanoma brain metastases with whole brain radiation therapy and temozolomide is reasonable based on one class II study. Level 3 Depending on individual circumstances there may be patients who benefit from the use of temozolomide or fotemustine in the therapy of their brain metastases. Molecular targeted agents Level 3 The use of epidermal growth factor receptor inhibitors may be of use in the management of brain metastases from non-small cell lung carcinoma.

The role of surgical resection in the management of newly diagnosed brain metastases: a systematic review and evidence-based clinical practice guideline

QUESTION

Should patients with newly-diagnosed metastatic brain tumors undergo open surgical resection versus whole brain radiation therapy (WBRT) and/or other treatment modalities such as radiosurgery, and in what clinical settings? Target population These recommendations apply to adults with a newly diagnosed single brain metastasis amenable to surgical resection. Recommendations Surgical resection plus WBRT versus surgical resection alone Level 1 Surgical resection followed by WBRT represents a superior treatment modality, in terms of improving tumor control at the original site of the metastasis and in the brain overall, when compared to surgical resection alone. Surgical resection plus WBRT versus SRS +/- WBRT Level 2 Surgical resection plus WBRT, versus stereotactic radiosurgery (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. Note The following question is fully addressed in the WBRT guideline paper within this series by Gaspar et al. Given that the recommendation resulting from the systematic review of the literature on this topic is also highly relevant to the discussion of the role of surgical resection in the management of brain metastases, this recommendation has been included below. Question Does surgical resection in addition to WBRT improve outcomes when compared with WBRT alone? Target population This recommendation applies to adults with a newly diagnosed single brain metastasis amenable to surgical resection; however, the recommendation does not apply to relatively radiosensitive tumors histologies (i.e., small cell lung cancer, leukemia, lymphoma, germ cell tumors and multiple myeloma). Recommendation Surgical resection plus WBRT versus WBRT alone Level 1 Class I evidence supports the use of surgical resection plus post-operative WBRT, as compared to WBRT alone, in patients with good performance status (functionally independent and spending less than 50% of time in bed) and limited extra-cranial disease. There is insufficient evidence to make a recommendation for patients with poor performance scores, advanced systemic disease, or multiple brain metastases.

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

Target population

This recommendation applies to adults with newly diagnosed brain metastases; however, the recommendation below does not apply to the exquisitely chemosensitive tumors, such as germinomas metastatic to the brain.

Recommendation

Should patients with brain metastases receive chemotherapy in addition to whole brain radiotherapy (WBRT)?

Level 1 Routine use of chemotherapy following WBRT for brain metastases has not been shown to increase survival and is not recommended. Four class I studies examined the role of carboplatin, chloroethylnitrosoureas, tegafur and temozolomide, and all resulted in no survival benefit. Two caveats are provided in order to allow the treating physician to individualize decision-making: First, the majority of the data are limited to non small cell lung (NSCLC) and breast cancer; therefore, in other tumor histologies, the possibility of clinical benefit cannot be absolutely ruled out. Second, the addition of chemotherapy to WBRT improved response rates in some, but not all trials; response rate was not the primary endpoint in most of these trials and end-point assessment was non-centralized, non-blinded, and post-hoc. Enrollment in chemotherapy-related clinical trials is encouraged.

The role of whole brain radiation therapy in the management of newly diagnosed brain metastases: a systematic review and evidence-based clinical practice guideline

Target population

This recommendation applies to adults with newly diagnosed single brain metastases amenable to surgical resection; however, the recommendation does not apply to relatively radiosensitive tumors histologies (i.e., small cell lung cancer, leukemia, lymphoma, germ cell tumors and multiple myeloma).

Recommendation

Surgical resection plus WBRT versus WBRT alone

Level 1 Class I evidence supports the use of surgical resection plus post-operative WBRT, as compared to WBRT alone, in patients with good performance status (functionally independent and spending less than 50% of time in bed) and limited extra-cranial disease. There is insufficient evidence to make a recommendation for patients with poor performance scores, advanced systemic disease, or multiple brain metastases.

If WBRT is used, is there an optimal dosing/fractionation schedule?

Target population

This recommendation applies to adults with newly diagnosed brain metastases.

Recommendation

Level 1 Class I evidence suggests that altered dose/fractionation schedules of WBRT do not result in significant differences in median survival, local control or neurocognitive outcomes when compared with “standard” WBRT dose/fractionation. (i.e., 30 Gy in 10 fractions or a biologically effective dose (BED) of 39 Gy10).

If WBRT is used, what impact does tumor histopathology have on treatment outcomes?

Target population

This recommendation applies to adults with newly diagnosed brain metastases.

Recommendation

Given the extremely limited data available, there is insufficient evidence to support the choice of any particular dose/fractionation regimen based on histopathology.

The following question is fully addressed in the surgery guideline paper within this series by Kalkanis et al. Given that the recommendation resulting from the systematic review of the literature on this topic is also highly relevant to the discussion of the role of WBRT in the management of brain metastases, this recommendation has been included below.

Does the addition of WBRT after surgical resection improve outcomes when compared with surgical resection alone?

Target population

This recommendation applies to adults with newly diagnosed single brain metastases amenable to surgical resection.

Recommendation

Surgical resection plus WBRT versus surgical resection alone

Level 1 Surgical resection followed by WBRT represents a superior treatment modality, in terms of improving tumor control at the original site of the metastasis and in the brain overall, when compared to surgical resection alone.

The role of steroids in the management of brain metastases: a systematic review and evidence-based clinical practice guideline

Do steroids improve neurologic symptoms in patients with metastatic brain tumors compared to no treatment? If steroids are given, what dose should be used? Comparisons include: (1) steroid therapy versus none. (2) comparison of different doses of steroid therapy.

Target population

These recommendations apply to adults diagnosed with brain metastases.

Recommendations

Steroid therapy versus no steroid therapy

Asymptomatic brain metastases patients without mass effect

Insufficient evidence exists to make a treatment recommendation for this clinical scenario.

Brain metastases patients with mild symptoms related to mass effect

Level 3 Corticosteroids are recommended to provide temporary symptomatic relief of symptoms related to increased intracranial pressure and edema secondary to brain metastases. It is recommended for patients who are symptomatic from metastatic disease to the brain that a starting dose of 4–8 mg/day of dexamethasone be considered.

Brain metastases patients with moderate to severe symptoms related to mass effect

Level 3 Corticosteroids are recommended to provide temporary symptomatic relief of symptoms related to increased intracranial pressure and edema secondary to brain metastases. If patients exhibit severe symptoms consistent with increased intracranial pressure, it is recommended that higher doses such as 16 mg/day or more be considered.

Choice of Steroid

Level 3 If corticosteroids are given, dexamethasone is the best drug choice given the available evidence.

Duration of Corticosteroid Administration

Level 3 Corticosteroids, if given, should be tapered slowly over a 2 week time period, or longer in symptomatic patients, based upon an individualized treatment regimen and a full understanding of the long-term sequelae of corticosteroid therapy.

Given the very limited number of studies (two) which met the eligibility criteria for the systematic review, these are the only recommendations that can be offered based on this methodology. Please see “Discussion” and “Summary” section for additional details.

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.

Multi-institutional phase I/II trial of stereotactic body radiation therapy for liver metastases

PURPOSE

To evaluate the efficacy and tolerability of high-dose stereotactic body radiation therapy (SBRT) for the treatment of patients with one to three hepatic metastases.

PATIENTS AND METHODS

Patients with one to three hepatic lesions and maximum individual tumor diameters less than 6 cm were enrolled and treated on a multi-institutional, phase I/II clinical trial in which they received SBRT delivered in three fractions. During phase I, the total dose was safely escalated from 36 Gy to 60 Gy. The phase II dose was 60 Gy. The primary end point was local control. Lesions with at least 6 months of radiographic follow-up were considered assessable for local control. Secondary end points were toxicity and survival.

RESULTS

Forty-seven patients with 63 lesions were treated with SBRT. Among them, 69% had received at least one prior systemic therapy regimen for metastatic disease (range, 0 to 5 regimens), and 45% had extrahepatic disease at study entry. Only one patient experienced grade 3 or higher toxicity (2%). Forty-nine discrete lesions were assessable for local control. Median follow-up for assessable lesions was 16 months (range, 6 to 54 months). The median maximal tumor diameter was 2.7 cm (range, 0.4 to 5.8 cm). Local progression occurred in only three lesions at a median of 7.5 months (range, 7 to 13 months) after SBRT. Actuarial in-field local control rates at one and two years after SBRT were 95% and 92%, respectively. Among lesions with maximal diameter of 3 cm or less, 2-year local control was 100%. Median survival was 20.5 months.

CONCLUSION

This multi-institutional, phase I/II trial demonstrates that high-dose liver SBRT is safe and effective for the treatment of patients with one to three hepatic metastases.

Multi-institutional phase I/II trial of stereotactic body radiation therapy for lung metastases

PURPOSE

To evaluate the efficacy and tolerability of high-dose stereotactic body radiation therapy (SBRT) for the treatment of patients with one to three lung metastases.

PATIENTS AND METHODS

Patients with one to three lung metastases with cumulative maximum tumor diameter smaller than 7 cm were enrolled and treated on a multi-institutional phase I/II clinical trial in which they received SBRT delivered in 3 fractions. In phase I, the total dose was safely escalated from 48 to 60 Gy. The phase II dose was 60 Gy. The primary end point was local control. Lesions with at least 6 months of radiographic follow-up were considered assessable for local control. Secondary end points included toxicity and survival.

RESULTS

Thirty-eight patients with 63 lesions were enrolled and treated at three participating institutions. Seventy-one percent had received at least one prior systemic regimen for metastatic disease and 34% had received at least two prior regimens (range, zero to five). Two patients had local recurrence after prior surgical resection. There was no grade 4 toxicity. The incidence of any grade 3 toxicity was 8% (three of 38). Symptomatic pneumonitis occurred in one patient (2.6%). Fifty lesions were assessable for local control. Median follow-up for assessable lesions was 15.4 months (range, 6 to 48 months). The median gross tumor volume was 4.2 mL (range, 0.2 to 52.3 mL). Actuarial local control at one and two years after SBRT was 100% and 96%, respectively. Local progression occurred in one patient, 13 months after SBRT. Median survival was 19 months.

CONCLUSION

This multi-institutional phase I/II trial demonstrates that high-dose SBRT is safe and effective for the treatment of patients with one to three lung metastases.

Black and white patients fare equally well when treated with postlumpectomy radiotherapy

PURPOSE

Some previous studies have demonstrated that black patients have inferior local-regional control and disease-free survival when treated with postlumpectomy radiotherapy. The intention of this study was to analyze the same outcomes with a larger series of black patients.

METHODS

A retrospective chart review was performed at an academic referral center, a community hospital, and an inner-city public hospital.

RESULTS

A total of 270 patients that received postlumpectomy radiotherapy were reviewed. Of those, 102 were black, 162 white, and six nonblack, nonwhite. The black patients were statistically significantly more likely to present with higher-stage disease (Stage II: 43.1% vs. 32.1%), positive lymph nodes (29.4% vs. 14.8%), higher-grade disease (Grade III: 35.3% vs. 24.1%), and age < 45. The actuarial local control at five years in the black patients was 95.5% and in the white patients was 94.8%. The actuarial five-year disease-free survival in the black patients was 90.3% and in the white patients was 91.7%. There was no statistically significant difference in either local control or disease free-survival in the black and white patients when matched by stage.

CONCLUSION

At five years, the local control and disease-free survival for black patients are equally as good as white patients.

Breast conservation is an effective option in Black, medically indigent patients

The purpose of the study was to evaluate the efficacy of lumpectomy and postoperative radiotherapy in an African-American, medically indigent population. From 1980 through 1996, a retrospective chart review was undertaken of the patients treated with radiotherapy after lumpectomy at an inner city hospital, whose patients are primarily African American and uninsured. One hundred and one patients were treated with breast conservation during this time. Of those, 72 were African American and with invasive carcinoma. The data were analyzed using JMP IN (SAS Institute). The study found that African-American patients with invasive carcinoma had 95.2% local control at 5 years and 87.9% at 10 years. The disease-free survival was 84.6% at 5 years and 65.3% at 10 years. Patients that received less than 50 Gray to the tumor bed had inferior local control, disease-free survival, and overall survival (p < 0.0001 for all three). The 5-year and 10-year local control for DCIS, in a limited number of patients, was 95.2%. We conclude that lumpectomy followed by radiotherapy is an effective treatment strategy in the high-risk population of African-American, medically indigent patients. The local control and disease-free survival compare favorably to published controls in this traditionally high-risk patient population.

'Loop' domain deletional mutant of Bcl-xL is as effective as p29Bcl-xL in inhibiting radiation-induced cytosolic accumulation of cytochrome c (cyt c), caspase-3 activity, and apoptosis

PURPOSE/OBJECTIVE

To investigate the effect of the enforced expression of p29Bcl-xL or its loop deletional mutant, p18Bcl-xLdelta, on irradiation-induced apoptosis and cell-cycle distribution of HL-60 cells.

MATERIALS & METHODS

We compared the irradiation-induced molecular cascade of apoptosis in control human AML HL-60/neo versus Bcl-xL overexpressing (approximately 8-fold) (HL-60/Bcl-xL) and HL-60/Bcl-XLdelta cells that express the loop domain deletional mutant construct (delta26-83 AA) of Bcl-xL. The three cell lines were irradiated with 6MV photons to varying doses up to 20 Gy. Following this, cytosolic cyt c levels, caspase-3 activity, and the Bcl-2 family of proteins were evaluated utilizing Western blot analysis (whole cell lysate or cytosolic S-100 fraction). Apoptosis was assessed by internucleosomal DNA fragmentation, Annexin-V staining and FACS analysis, as well as by morphologic criteria. The cell-cycle effects of radiation were analyzed by flow cytometry.

RESULTS

Eight hours following irradiation (12 Gy) of HL-60/neo cells, a marked increase (approximately 8-fold) in the cytosolic accumulation of cyt c in the S-100 fraction was observed. This was associated with the cleavage of caspase-3, as well as the generation of its poly (ADP-ribose) polymerase (PARP) and DFF (DNA fragmentation factor)-45 cleavage activity. Twenty-four to forty-eight hours after irradiation, internucleosomal DNA fragmentation and positive Annexin-V staining (32.3+/-3.3%) was detected in HL-60/neo cells. In contrast, in both HL-60/Bcl-xL and HL-60/Bcl-xLdelta cells, a significantly lower percentage of apoptotic cells (p<0.05) were detected and internucleosomal DNA fragmentation was not induced. Following irradiation, Western analysis neither demonstrated any significant alteration in Bcl-2, p29Bcl-xL, p18Bcl-xLdelta, or Bax; nor induced CD95 (Fas receptor) or Fas ligand expression in any cell type. However, in all cell types, irradiation produced approximately a 2-fold increase in the percentage of cells in the G2/M phase of the cell cycle.

CONCLUSION

These results demonstrate that an intact loop domain is not necessary for the full antiapoptotic function of Bcl-xL against irradiation-induced cytosolic accumulation of cyt c, caspase activation, and apoptosis of HL-60 cells. Additionally, the cell-cycle effects of ionizing radiation in HL-60 cells are not affected by enforced expression of Bcl-xL or Bcl-xLdelta.