Stereotactic radiosurgery with and without whole-brain radiotherapy for newly diagnosed brain metastases

Evaluation of response to stereotactic radiosurgery in patients with radioresistant brain metastases

PURPOSE

Renal cell carcinoma (RCC) and melanoma have been considered 'radioresistant' due to the fact that they do not respond to conventionally fractionated radiation therapy. Stereotactic radiosurgery (SRS) provides high-dose radiation to a defined target volume and a limited number of studies have suggested the potential effectiveness of SRS in radioresistant histologies. We sought to determine the effectiveness of SRS for the treatment of patients with radioresistant brain metastases.

MATERIALS AND METHODS

We performed a retrospective review of our institutional database to identify patients with RCC or melanoma brain metastases treated with SRS. Treatment response were determined in accordance with the Response Evaluation Criteria in Solid Tumors.

RESULTS

We identified 53 radioresistant brain metastases (28% RCC and 72% melanoma) treated in 18 patients. The mean target volume and coverage was 6.2 ± 9.5 mL and 95.5% ± 2.9%, respectively. The mean prescription dose was 20 ± 4.9 Gy. Forty lesions (75%) demonstrated a complete/partial response and 13 lesions (24%) with progressive/stable disease. Smaller target volume (p < 0.001), larger SRS dose (p < 0.001), and coverage (p = 0.008) were found to be positive predictors of complete response to SRS.

CONCLUSION

SRS is an effective management option with up to 75% response rate for radioresistant brain metastases. Tumor volume and radiation dose are predictors of response and can be used to guide the decision-making for patients with radioresistant brain metastases.

Quality of life is maintained using Gamma Knife radiosurgery: a prospective study of a brain metastases patient cohort

OBJECTIVE

Gamma Knife radiosurgery (GKRS) is increasingly used in the management of brain metastases (BMs), but few studies have evaluated how GKRS impacts quality of life (QOL). The aim of this study was to monitor QOL as the primary end point following GKRS in a patient cohort with BM.

METHODS

The study included 97 consecutive patients with 1–6 BMs treated with GKRS between May 2010 and September 2011. QOL was assessed at baseline and at 1, 3, 6, 9, and 12 months postoperatively using the Functional Assessment of Cancer Therapy–Brain (FACT-BR) questionnaire with the brain cancer subscale (BRCS) questionnaire. Factors predicting QOL were identified by mixed linear regression analyses. Local control and toxicity were evaluated according to Response Evaluation Criteria in Solid Tumors (RECIST) and the European Organisation for Research and Treatment/Radiation Therapy Oncology Group (EORTC/RTOG) criteria of late effects, respectively.

RESULTS

Compliance was high from baseline (97%) to 12-month follow-up (78%). Mean BRCS scores remained high during follow-up: they improved in 66% of patients and remained unchanged in 6% at 9 months. Local control (p = 0.018), improved symptoms (p = 0.005), and stable extracerebral disease (p = 0.001) correlated with high QOL-BRCS score. High baseline recursive partitioning analysis class predicted improved QOL (p = 0.031), whereas high Karnofsky Performance Scale score (p = 0.017), asymptomatic BMs (p = 0.001), and no cognitive deficits (p = 0.033) or seizures (p = 0.040) predicted high, stable QOL-BRCS during the 12-month follow-up.

CONCLUSIONS

QOL remained stable for up to 12 months following GKRS for the total cohort. High QOL was reported if local control occurred, cerebral symptoms improved/stabilized, or the need for steroids declined, which all reflected successful GKRS. Conversely, low QOL accompanied progression of intra- and extracerebral disease. Based on the study findings, GKRS appears to be a safe and effective treatment option for patients with BMs.

Reirradiation of Pediatric Tumors Using Hypofractionated Stereotactic Radiotherapy

BACKGROUND

This study aimed to evaluate the efficacy and safety of hypofractionated stereotactic radiotherapy for reirradiation of recurrent pediatric tumors.

METHODS AND MATERIALS

The study included 23 pediatric patients who were reirradiated using hypofractionated stereotactic radiotherapy in the radiation oncology department between January 2008 and November 2013. In total, 33 tumors were treated-27 (82%) cranial and 6 (18%) extracranial. Hypofractionated stereotactic radiotherapy was administered due to recurrent disease in 31 (94%) tumors and residual disease in 2 (6%) tumors. The median total dose was 25 Gy (range: 15-40 Gy), and the median follow-up was 20 months (range: 2-68 months).

RESULTS

The 1-year and 2-year local control rates in the entire study population were 42% and 31%, respectively. The median local control time was 11 months (range: 0-54 months) following hypofractionated stereotactic radiotherapy. The patients with tumor response after hypofractionated stereotactic radiotherapy had significantly longer local control than the patients with post-hypofractionated stereotactic radiotherapy tumor progression (21 vs 3 months, P < .001). Tumor volume <1.58 cm³ was correlated (not significantly) with better local control (23 vs 7 months, P = .064).

CONCLUSION

Reirradiation of pediatric tumors using hypofractionated stereotactic radiotherapy is a safe and effective therapeutic approach. This treatment modality should be considered as a treatment option in selected pediatric patients.

Intensity-Modulated Radiosurgery for Patients with Brain Metastases: A Mature Outcomes Analysis

The purpose of this study was to evaluate the outcomes of patients with brain metastases treated by tomotherapeutic Intensity-modulated Radiosurgery (IMRS). Using retrospective chart review, we analyzed the outcomes of 78 patients (age 33–83 years, median 57 years) who underwent 111 sessions of IMRS (1 to 7 sessions per patient, median 1) for brain metastases (1 to 4 targets per IMRS session, median 1) treated between 2000 and 2005 using a serial tomotherapeutic intensity-modulated radiotherapy treatment (IMRT) planning and delivery system (Peacock, Nomos Corp., Cranberry Township, PA). Treatment planning was performed using an inverse treatment planning optimization algorithm that was optimized for IMRS. A median prescription dose of 15 Gy in combination with WBI, and median 20 Gy for IMRS alone was delivered using 2–4 couch angles over 4–24 rotational arcs. Overall survival was calculated using Kaplan-Meier analysis. To determine the effects of prognostic variables on survival, univariate and multivariate analyses using proportional hazards were performed to assess the effects of age, tumor size, the combination with whole brain irradiation, presence of multiple brain metastases, and presence of extracranial disease. The median overall survival was 6.5 months (95% CI, 5.5–7.9). One- and two-year survival rates were 24% and 10%. In multivariate analyses, age greater than 60 years was the only statistically significant variable that affected survival (hazard rate 1.29, p=0.049). We conclude that tomotherapeutic IMRS is safe and effective to treat patients with brain metastases.

Cost-effectiveness of stereotactic radiosurgery with and without whole-brain radiotherapy for the treatment of newly diagnosed brain metastases

Object

Stereotactic radiosurgery (SRS) alone is increasingly used in patients with newly diagnosed brain metastases. Stereotactic radiosurgery used together with whole-brain radiotherapy (WBRT) reduces intracranial failure rates, but this combination also causes greater neurocognitive toxicity and does not improve survival. Critics of SRS alone contend that deferring WBRT results in an increased need for salvage therapy and in higher costs. The authors compared the cost-effectiveness of treatment with SRS alone, SRS and WBRT (SRS+WBRT), and surgery followed by SRS (S+SRS) at the authors' institution.

Methods

The authors retrospectively reviewed the medical records of 289 patients in whom brain metastases were newly diagnosed and who were treated between May 2001 and December 2007. Overall survival curves were plotted using the Kaplan-Meier method. Multivariate proportional hazards analysis (MVA) was used to identify factors associated with overall survival. Survival data were complete for 96.2% of patients, and comprehensive data on the resource use for imaging, hospitalizations, and salvage therapies were available from the medical records. Treatment costs included the cost of initial and all salvage therapies for brain metastases, hospitalizations, management of complications, and imaging. They were computed on the basis of the 2007 Medicare fee schedule from a payer perspective. Average treatment cost and average cost per month of median survival were compared. Sensitivity analysis was performed to examine the impact of variations in key cost variables.

Results

No significant differences in overall survival were observed among patients treated with SRS alone, SRS+WBRT, or S+SRS with respective median survival of 9.8, 7.4, and 10.6 months. The MVA detected a significant association of overall survival with female sex, Karnofsky Performance Scale (KPS) score, primary tumor control, absence of extracranial metastases, and number of brain metastases. Salvage therapy was required in 43% of SRS-alone and 26% of SRS+WBRT patients (p < 0.009). Despite an increased need for salvage therapy, the average cost per month of median survival was $2412 per month for SRS alone, $3220 per month for SRS+WBRT, and $4360 per month for S+SRS (p < 0.03). Compared with SRS+WBRT, SRS alone had an average incremental cost savings of $110 per patient. Sensitivity analysis confirmed that the average treatment cost of SRS alone remained less than or was comparable to SRS+WBRT over a wide range of costs and treatment efficacies.

Conclusions

Despite an increased need for salvage therapy, patients with newly diagnosed brain metastases treated with SRS alone have similar overall survival and receive more cost-effective care than those treated with SRS+WBRT. Compared with SRS+WBRT, initial management with SRS alone does not result in a higher average cost.

Stereotactic radiosurgery and radiation therapy for spinal tumors

Spinal tumors constitute 15% of all CNS neoplasms. Radiation therapy can be administered for palliation of pain and spinal cord compression. However, the amount of radiation that can be administered is often limited by the tolerance of the spinal cord, especially in cases where prior radiation therapy has been given. Stereotactic radiosurgery and radiotherapy allow the delivery of a higher dose of radiation to spinal lesions, while limiting the spinal cord dose to below the tolerance level. These are technically demanding procedures and should be performed only when proper equipment and expertise are available. Data on spinal stereotactic radiosurgery and radiotherapy have emerged in recent years. This review summarizes the clinical applications of stereotactic radiosurgery and radiotherapy for spinal tumors.

Delivery of nanoparticles to brain metastases of breast cancer using a cellular Trojan horse

As systemic cancer therapies improve and are able to control metastatic disease outside the central nervous system, the brain is increasingly the first site of relapse. The blood-brain barrier (BBB) represents a major challenge to the delivery of therapeutics to the brain. Macrophages originating from circulating monocytes are able to infiltrate brain metastases while the BBB is intact. Here, we show that this ability can be exploited to deliver both diagnostic and therapeutic nanoparticles specifically to experimental brain metastases of breast cancer.

Stereotactic radiosurgery with or without whole-brain radiotherapy for brain metastases: an update

Brain metastases are unfortunately a common occurrence in patients with cancer. Whole-brain radiation therapy (WBRT) is still considered the standard of care in the treatment of brain metastases. Stereotactic radiosurgery (SRS) offers the additional ability to treat tumors with relative sparing of normal brain tissue in a single fraction. While the addition of SRS to WBRT has been shown to improve survival and local tumor control in selected patients, the idea of deferring WBRT in order to avoid its effects on normal tissues and using SRS alone continues to generate significant discussion and interest. Three recent randomized trials from Japan, Europe and the MD Anderson Cancer Center (TX, USA) have attempted to address this issue. In this article, we update a previous review by discussing these trials to compare the outcomes for SRS alone versus SRS plus WBRT for limited metastases. We also discuss recent nonrandomized evidence for the use of SRS alone for oligometastatic disease.

Outcomes and prognostic factors for patients with brainstem metastases undergoing stereotactic radiosurgery

BACKGROUND

Treatment of tumors metastatic to the brainstem with stereotactic radiosurgery (SRS) has not been widely studied.

OBJECTIVE

To identify the effects of SRS on patients with brainstem metastases by assessing duration of local progression-free survival (LPFS) and overall survival.

METHODS

We retrospectively reviewed clinical data collected from 60 patients undergoing linear accelerator-based SRS for tumors metastatic to the brainstem between August 1994 and December 2007. The LPFS and overall survival were calculated with the Kaplan-Meier method. Prognostic factors were evaluated with the log-rank test and Cox proportional hazards model.

RESULTS

The median age of patients was 61 years (range, 39-85 years); the median treated lesion volume was 1.0 mL (range, 0.1-8.7 mL); and the median SRS dose was 15 Gy (range, 8-18 Gy). The median overall survival interval after SRS was 4 months (95% confidence interval, 3.4-4.9 months); crude local tumor control was 76%; and median LPFS was 5.7 months (95% confidence interval, 3.0-8.4 months). Shorter overall survival was associated with a pretreatment tumor volume ≥4 mL (P < .001) and male sex (P = .03). Shorter LPFS was associated with a pretreatment tumor volume ≥4 mL (P = .008), a melanoma primary tumor (P = .002), and the presence of necrosis in pre-SRS magnetic resonance imaging (P = .04). A Basic Score for Brain Metastases of 2 to 3 vs 1 (P = .007) and a Score Index for Radiosurgery >5 (P = .003) were significantly associated with longer survival. Twelve patients (20%) developed SRS-related complications.

CONCLUSION

Stereotactic radiosurgery provides noninvasive treatment and favorable local tumor control for patients with brainstem metastases.

Effect of lapatinib on the outgrowth of metastatic breast cancer cells to the brain

BACKGROUND

The brain is increasingly being recognized as a sanctuary site for metastatic tumor cells in women with HER2-overexpressing breast cancer who receive trastuzumab therapy. There are no approved or widely accepted treatments for brain metastases other than steroids, cranial radiotherapy, and surgical resection. We examined the efficacy of lapatinib, an inhibitor of the epidermal growth factor receptor (EGFR) and HER2 kinases, for preventing the outgrowth of breast cancer cells in the brain in a mouse xenograft model of brain metastasis.

METHODS

EGFR-overexpressing MDA-MB-231-BR (231-BR) brain-seeking breast cancer cells were transfected with an expression vector that contained or lacked the HER2 cDNA and used to examine the effect of lapatinib on the activation (ie, phosphorylation) of cell signaling proteins by immunoblotting, on cell growth by the tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, and on cell migration using a Boyden chamber assay. The outgrowth of large (ie, >50 microm(2)) and micrometastases was counted in brain sections from nude mice that had been injected into the left cardiac ventricle with 231-BR cells and, beginning 5 days later, treated by oral gavage with lapatinib or vehicle (n = 22-26 mice per treatment group). All statistical tests were two-sided.

RESULTS

In vitro, lapatinib inhibited the phosphorylation of EGFR, HER2, and downstream signaling proteins; cell proliferation; and migration in 231-BR cells (both with and without HER2). Among mice injected with 231-BR-vector cells, those treated with 100 mg lapatinib/kg body weight had 54% fewer large metastases 24 days after starting treatment than those treated with vehicle (mean number of large metastases per brain section: 1.56 vs 3.36, difference = 1.80, 95% confidence interval [CI] = 0.92 to 2.68, P < .001), whereas treatment with 30 mg lapatinib/kg body weight had no effect. Among mice injected with 231-BR-HER2 cells, those treated with either dose of lapatinib had 50%-53% fewer large metastases than those treated with vehicle (mean number of large metastases per brain section, 30 mg/kg vs vehicle: 3.21 vs 6.83, difference = 3.62, 95% CI = 2.30 to 4.94, P < .001; 100 mg/kg vs vehicle: 3.44 vs 6.83, difference = 3.39, 95% CI = 2.08 to 4.70, P < .001). Immunohistochemical analysis revealed reduced phosphorylation of HER2 in 231-BR-HER2 cell-derived brain metastases from mice treated with the higher dose of lapatinib compared with 231-BR-HER2 cell-derived brain metastases from vehicle-treated mice (P < .001).

CONCLUSIONS

Lapatinib is the first HER2-directed drug to be validated in a preclinical model for activity against brain metastases of breast cancer.

Role of stereotactic radiosurgery and fractionated stereotactic radiotherapy in pediatric brain tumors

Brain tumors are the most common solid tumor in childhood. Surgery and/or fractionated radiotherapy are conventional treatment modalities. Stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT) are advanced radiation therapy techniques that have been frequently used in adults with brain tumors but they are less frequently used in pediatric patients. SRS and FSRT can potentially add to the armamentarium against brain tumors in children. This article will review the role of SRS and FSRT in the management of pediatric brain tumors.

Successful treatment of a skull base malignant rhabdoid tumor with surgery, chemotherapy and gamma Knife-based stereotactic radiosurgery in a young child

Most childhood rhabdoid tumors occur in the kidney or central nervous system but they can occur in other sites and they usually run an aggressive clinical course. We report a case of an 8-month-old boy with a right temporal bone rhabdoid tumor treated with surgery, chemotherapy and Gamma Knife-based stereotactic radiosurgery. The patient remained alive after 61 months and repeat magnetic resonance imaging (MRI) of the brain showed no evidence of recurrence. There were no obvious endocrine deficits or growth abnormalities at last follow-up. Gamma Knife-based stereotactic radiosurgery may have a role in the management of very young children with skull base tumors.

A PILOT STUDY OF NEUROCOGNITIVE FUNCTION IN PATIENTS WITH ONE TO THREE NEW BRAIN METASTASES INITIALLY TREATED WITH STEREOTACTIC RADIOSURGERY ALONE

OBJECTIVE

Whether to administer or omit adjuvant whole-brain radiation therapy in conjunction with stereotactic radiosurgery (SRS) in the initial management of patients with one to three newly diagnosed brain metastases is the subject of debate. This report provides data from a pilot study in which neurocognitive function (NCF) was prospectively measured for patients with one to three newly diagnosed brain metastases treated with initial SRS alone.

METHODS

Fifteen patients were prospectively treated with initial SRS alone. Assessment of NCF and magnetic resonance imaging scans were performed.

RESULTS

At baseline, 67% of the patients had impairment on one or more tests of NCF. The domains most frequently impaired at baseline were executive function, motor dexterity, and learning/memory with an incidence of 50, 40, and 27% respectively. Brain metastasis volume (.3 cm3) measured at the time of initial SRS treatment was associated with worse performance on a measure of attention (P &lt; 0.05). At 1 month, declines in the learning/memory and motor dexterity domains were most common. In a subgroup of five patients still alive 200 days after enrollment, four patients (80%) demonstrated stable or improved learning/memory, three (60%) demonstrated stable or improved executive function, and three (60%) demonstrated stable or improved motor dexterity relative to their baseline evaluation.

CONCLUSION

Although two-thirds of the brain metastasis patients had impaired NCF at baseline, the majority of five long-term survivors had stable or improved NCF performance across executive function, learning/memory, and motor dexterity.