Radiosurgery in patients with renal cell carcinoma metastasis to the brain: long-term outcomes and prognostic factors influencing survival and local tumor control

Radioresistant Pulmonary Oligometastatic and Oligoprogressive Lesions From Nonlung Primaries: Impact of Histology and Dose-Fractionation on Local Control After Radiation Therapy

Purpose

We investigated whether pulmonary metastases from historically considered radioresistant primaries would have inferior local control after radiation therapy than those from nonradioresistant nonlung primaries, and whether higher biologically effective dose assuming alpha/beta=10 (BED10) would be associated with superior local control.

Methods and Materials

We identified patients treated with radiation therapy for oligometastatic or oligoprogressive pulmonary disease to 1 to 5 lung metastases from nonlung primaries in 2013 to 2020 at a single health care system. Radioresistant primary cancers included colorectal carcinoma, endometrial carcinoma, renal cell carcinoma, melanoma, and sarcoma. Nonradioresistant primary cancers included breast, bladder, esophageal, pancreas, and head and neck carcinomas. The Kaplan-Meier estimator, log-rank test, and multivariable Cox proportional hazards regression were used to compare local recurrence-free survival (LRFS), new metastasis-free survival, progression-free survival, and overall survival.

Results

Among 114 patients, 73 had radioresistant primary cancers. The median total dose was 50 Gy (IQR, 50-54 Gy) and the median number of fractions was 5 (IQR, 3-5). Median follow-up time was 59.6 months. One of 41 (2.4%) patients with a nonradioresistant metastasis experienced local failure compared with 18 of 73 (24.7%) patients with radioresistant metastasis (log-rank P = .004). Among radioresistant metastases, 12 of 41 (29.2%) patients with colorectal carcinoma experienced local failure compared with 6 of 32 (18.8%) with other primaries (log-rank P = .018). BED10 ≥100 Gy was associated with decreased risk of local recurrence. On univariable analysis, BED10 ≥100 Gy (hazard ratio [HR], 0.263; 95% CI, 0.105-0.656; P = .004) was associated with higher LRFS, and colorectal primary (HR, 3.060; 95% CI, 1.204-7.777; P = .019) was associated with lower LRFS, though these were not statistically significant on multivariable analysis. Among colorectal primary patients, BED10 ≥100 Gy was associated with higher LRFS (HR, 0.266; 95% CI, 0.072-0.985; P = .047) on multivariable analysis.

Conclusions

Local control after radiation therapy was encouraging for pulmonary metastases from most nonlung primaries, even for many of those classically considered to be radioresistant. Those from colorectal primaries may benefit from testing additional strategies, such as resection or systemic treatment concurrent with radiation.

Fatal tumoral hemorrhage from brain metastases of renal cell carcinoma after stereotactic radiotherapy and immune checkpoint inhibitor and vascular endothelial growth factor-targeted therapy combinations

Introduction

Brain metastasis in renal cell carcinoma, which is reported in 10% of cases, leads to significant morbidity and mortality. Establishment of appropriate and safe treatment for brain metastasis renal cell carcinoma remains a pressing need.

Case presentation

A 56-year-old female patient, presenting with anorexia, headache, and occipital swelling, was subsequently diagnosed with clear cell renal cell carcinoma with multiple metastases, including intracranial and epicranial tumors. The patient initially underwent stereotactic radiotherapy for metastatic brain tumors and then received combination therapy with pembrolizumab and lenvatinib. However, after 30 days of treatment, the patient experienced a sudden loss of consciousness due to massive multifocal intracranial hemorrhage, leading to her death the following day.

Conclusion

Although fatal tumoral hemorrhage during combined stereotactic radiotherapy and immune checkpoint inhibitor/VEGF-targeted therapy for patients with brain metastasis renal cell carcinoma is an extremely rare complication, it should always be considered a possibility.

Stereotactic body radiotherapy for inoperable patients with renal carcinoma

INTRODUCTION

The objective of this study was to analyze the dose-dependent safety profiles of stereotactic body radiation therapy (SBRT) in patients with inoperable small renal cell carcinoma (RCC).

MATERIAL

This is a retrospective study from a single institution including patients with RCC treated between 2011 and 2020 with SBRT on the primary tumor or on a local recurrence after surgery. All patients had been declared inoperable or refused surgery. The patients were divided into two dose level groups: group 1 (BED10<60Gy) and group 2 (BED10≥60Gy). Acute and late toxicities, renal function and local control (LC) were compared between the two groups.

RESULTS

A total of 24 patients were analyzed with an average follow-up of 25.1 months. Nine patients (37%) and three patients (14%) reported grade 1-2 acute and late toxicities, respectively. No grade≥3 acute and late toxicities were observed. There was no significant difference in acute and late toxicities between the two groups (P=0.21 and P=0.27, respectively). There was no significant difference in estimated glomerular filtration rate in the 15 patients, eligible for renal toxicity analysis between the pre-radiation and the 12-month follow-up (P=0.1) and the last follow-up (P=0.06). LC at the last follow-up was noted in 19 out of 23 patients (83%) and was based on imaging acquisition. LC was 77.8% for group 1 and 85.7% for group 2 (P=1.95).

CONCLUSION

Dose escalation was not associated with an increase in acute and late grade≥2 toxicities. There appears to be a trend towards increased LC at higher doses.

Early tumor-related hemorrhage after stereotactic radiosurgery of brain metastases: Systematic review of reported cases

OBJECTIVE

Early (within 72 h) tumor-related hemorrhage (TRH) after stereotactic radiosurgery (SRS) of brain metastases (BM) has been reported only occasionally. Systematic review of such cases was done.

METHODS

Literature search was performed through PubMed according to PRISMA guidelines using combination of the following medical subject headings: "hemorrhage," "stereotactic radiosurgery," and "brain metastasis."

RESULTS

In total, 7 case reports and 8 clinical series, which noted early TRH after SRS of BM were identified. Scarce and inconsistent data precluded their precise synthesis and statistical analysis. BM of renal cell carcinoma comprised around one-third of reported cases. In 4 patients with multiple BM, TRH after SRS was noted simultaneously in several irradiated tumors. Considering 17 reported cases overall, in 3 patients TRH occurred during SRS session itself, in 4 within several minutes upon completion of treatment, in 7 within several hours thereafter, and in 3 on the third posttreatment day. Out of 11 reported cases providing detailed outcome, 6 patients died shortly after the ictus, 2 others were severely disabled at discharge, and 3 demonstrated good-to-moderate recovery. Overall, among evaluated series the median rates of early TRH after SRS for BM were 0.8% per patient (range, 0.4 - 1.9%) and 0.3% per tumor (range, 0.05 - 0.8%).

CONCLUSION

Early TRH is very rare, but potentially life-threatening complication of SRS for BM; thus, its risk (while extremely low) and possible consequences should be discussed at the time of obtaining informed consent.

Immunotherapy: an emerging modality to checkmate brain metastasis

The diagnosis of brain metastasis (BrM) has historically been a dooming diagnosis that is nothing less than a death sentence, with few treatment options for palliation or prolonging life. Among the few treatment options available, brain radiotherapy (RT) and surgical resection have been the backbone of therapy. Within the past couple of years, immunotherapy (IT), alone and in combination with traditional treatments, has emerged as a reckoning force to combat the spread of BrM and shrink tumor burden. This review compiles recent reports describing the potential role of IT in the treatment of BrM in various cancers. It also examines the impact of the tumor microenvironment of BrM on regulating the spread of cancer and the role IT can play in mitigating that spread. Lastly, this review also focuses on the future of IT and new clinical trials pushing the boundaries of IT in BrM.

Single fraction stereotactic radiosurgery and fractionated stereotactic radiotherapy provide equal prognosis with overall survival in patients with brain metastases at diagnosis without surgery at primary site

Background and purpose

Stereotactic radiosurgery (SRS) and fractionated stereotactic radiation therapy (SRT) are both treatments shown to be effective in treating brain metastases (BMs). However, it is unknown how these treatments compare in effectiveness and safety in cancer patients with BMs regardless of the primary cancer. The main objective of this study is to investigate the SRS and SRT treatments' associations with the overall survival (OS) of patients diagnosed with BMs using the National Cancer Database (NCDB).

Materials and methods

Patients in the NCDB with breast cancer, non-small cell lung cancer, small cell lung cancer, other lung cancers, melanoma, colorectal cancer, or kidney cancer who had BMs at the time of their primary cancer diagnosis and received either SRS or SRT as treatment for their BMs were included in the study. We analyzed OS with a Cox proportional hazard analysis that adjusted variables associated with improved OS during univariable analysis.

Results

Of the total 6,961 patients that fit the criteria for the study, 5,423 (77.9%) received SRS and 1,538 (22.1%) received SRT. Patients who received SRS treatment had a median survival time of 10.9 (95% CI [10.5-11.3]), and those who received SRT treatment had a median survival time of 11.3 (95% CI [10.4-12.3]) months. This difference was not found to be significant (Log-rank P = 0.31). Multivariable Cox proportional hazard analysis did not yield a significant difference between the treatments' associations with OS (Hazard Ratio: 0.942, CI 95% [0.882-1.006]; P = .08) or SRS vs. SRT.

Conclusions

In this analysis, SRS and SRT did not show a significant difference in their associations with OS. Future studies investigating the neurotoxicity risks of SRS as compared to SRT are warranted.

Evaluating the impact of early identification of asymptomatic brain metastases in metastatic renal cell carcinoma

BACKGROUND

Brain metastases (BM) in metastatic renal cell carcinoma (mRCC) have been reported to be present in up to 25% of patients diagnosed with mRCC. There is limited published literature evaluating the role of routine intra-cranial imaging for the screening of asymptomatic BM in mRCC.

AIMS

To evaluate the potential utility of routine intra-cranial imaging, a retrospective cohort study was conducted to characterize the outcomes of mRCC patients who presented with asymptomatic BM, as compared to symptomatic BM.

METHODS AND RESULTS

The Canadian Kidney Cancer Information System (CKCis) database was used to identify mRCC patients diagnosed with BM. This cohort was divided into two groups based on the presence or absence of BM symptoms. Details regarding patient demographics, disease characteristics, systemic treatments, BM characteristics and survival outcomes were extracted. Statistical analysis was through chi-square tests, analysis of variance, and Kaplan-Meier method to characterize survival outcomes. A p-value of <0.05 was considered statistically significant for all analyses. A total of 267 mRCC patients with BM were identified of which 106 (40%) presented with asymptomatic disease. The majority of patients presented with multiple (i.e., >1) BM (75%) with no significant differences noted in number of BM or BM-directed therapy received in symptomatic, as compared to asymptomatic BM patients. Median [95% confidence interval (CI)] overall survival (OS) from mRCC diagnosis was 42 months (95% CI: 32-62) for patients with asymptomatic BM, and 39 months (95% CI: 29-48) with symptomatic BM (p = 0.10). OS from time of BM diagnosis was 28 months (95% CI: 18-42) for the asymptomatic BM group, as compared to 13 months (95% CI: 10-21) in the symptomatic BM group (p = 0.04).

CONCLUSIONS

Given a substantial proportion of patients may present with asymptomatic BM, limiting intra-cranial imaging to patients with symptomatic BM, may be associated with a missed opportunity for timely diagnosis and treatment. The utility of routine intra-cranial imaging in patients with renal cell carcinoma, warrants further prospective evaluation.

VEGFR-TKI treatment for radiation-induced brain injury after gamma knife radiosurgery for brain metastases from renal cell carcinomas

OBJECTIVE

Antiangiogenic vascular endothelial growth factor receptor tyrosine kinase inhibitors play an essential role in systemic therapy for renal cell carcinoma. Given the anti-edematous effect of bevacizumab, an antiangiogenic antibody targeting vascular endothelial growth factor, vascular endothelial growth factor receptor tyrosine kinase inhibitors should exert therapeutic effects on radiation-induced brain injury after stereotactic radiosurgery. This preliminary study aimed to investigate the therapeutic effect of vascular endothelial growth factor receptor tyrosine kinase inhibitor against radiation-induced brain injury.

METHODS

Magnetic resonance images for six patients treated with vascular endothelial growth factor receptor tyrosine kinase inhibitors who were diagnosed with radiation-induced brain injury following gamma knife radiosurgery were retrospectively reviewed.

RESULTS

The median brain edema volume and tumour mass volume in the pre-tyrosine kinase inhibitor period were 57.6 mL (range: 39.4-188.2) and 3.2 mL (range: 1.0-4.6), respectively. Axitinib, pazopanib (followed by cabozantinib) and sunitinib were administered in four, one and one cases, respectively. The median brain edema volume and tumour mass volume in the post-tyrosine kinase inhibitor period were 4.8 mL (range: 1.5-27.8) and 1.6 mL (range: 0.4-3.6), respectively. The median rates of reduction in brain edema volume and tumour mass volume were 90.8% (range: 51.9-97.6%) and 57.2% (range: 20.0-68.6%), respectively. The post-tyrosine kinase inhibitor values for brain edema volume (P = 0.027) and tumour mass volume (P = 0.008) were significantly lower than the pre-tyrosine kinase inhibitor values. Changes in volume were correlated with tyrosine kinase inhibitor use.

CONCLUSION

This study is the first to demonstrate the therapeutic effects of vascular endothelial growth factor receptor tyrosine kinase inhibitors on radiation-induced brain injury in patients with brain metastases from renal cell carcinoma treated via gamma knife radiosurgery.

The Emerging Role of Radiation Therapy in Renal Cell Carcinoma

Advancements in radiation delivery technology have made it feasible to treat tumors with ablative radiation doses via stereotactic ablative radiation therapy (SAbR) at locations that were previously not possible. Renal cell cancer (RCC) was initially thought to be radioresistant, even considered toxic, in the era of conventional protracted course radiation. However, SAbR has been demonstrated to be safe and effective in providing local control to both primary and metastatic RCC by using ablative radiation doses. SAbR can be integrated with other local and systemic therapies to provide optimal management of RCC patients. We will discuss the rationale and available evidence for the integration and sequencing of SAbR with local and systemic therapies for RCC.

Sarcomatoid variant of urothelial carcinoma in the renal pelvis with brain metastasis: a case report

Sarcomatoid urothelial carcinoma (UC) of the renal pelvis is rare. It is a high-grade malignant tumor that contains both epithelial and mesenchymal elements. Brain metastases from renal pelvis UC are infrequent and represented in few cases. We report a 68-year-old female with a right renal mass diagnosed as a UC with a sarcomatoid variant. The patient underwent a right radical nephroureterectomy and received chemotherapy. She developed brain metastasis in the left temporal area two months later. Therefore, metastasectomy and palliative brain radiotherapy were performed for her. Sadly, her general condition worsened, and she passed away after one month. Brain metastasis in patients with UC is rare and poorly understood. Therefore, we describe the clinico pathological characteristics, including the clinical follow-up of our case with a focus on the treatment and outcome.

Stereotactic radiosurgery results for brain metastasis patients with renal cancer: A validity study of Renal Graded Prognostic Assessment and proposal of a new grading index (JLGK2101 Study)

Background and purpose

The Renal Graded Prognostic Assessment (GPA) is relatively new and has not been sufficiently validated using a different dataset. We thus developed a new grading index, the Renal Brain Metastasis Score (Renal-BMS).

Materials and methods

Using our dataset including 262 renal cancer patients with brain metastases (BMs) undergoing stereotactic radiosurgery (SRS) (test series), we validity tested the Renal-GPA. Next, we applied clinical factor-survival analysis to the test series and thereby developed the Renal-BMS. This system was then validated using another series of 352 patients independently undergoing SRS at nine gamma knife facilities in Japan (verification series).

Results

Using the test series, with the Renal-GPA, 95% confidence intervals (CIs) of the post-SRS median survival times (MSTs) overlapped between pairs of neighboring subgroups. Among various pre-SRS clinical factors of the test series, six were highly associated with overall survival. Therefore, we assigned scores for six factors, i.e., "KPS ≥ 80%/<80% (0/3)", "tumor numbers 1-4/≥5 (score; 0/2)", "controlled primary cancer/not (0/2)", "existing extra-cerebral metastases/not (0/3)", "blood hemoglobin ≥ 11.0/<11.0 g/dl (0/1)" and "interval from primary cancer to SRS ≥ 5/<5 years (0/1)". Patients were categorized into three subgroups according to the sum of scores, i.e., 0-4, 5-8 and 9-12. In the test and verification series, post-SRS MSTs differed significantly (p < 0.0001) with no overlaps of 95% CIs among the three subgroups.

Conclusions

The Renal BMS has the potential to be very useful to physicians selecting among aggressive treatment modalities for renal cancer patients with BMs.

Significance of upfront cytoreductive nephrectomy stratified by IMDC risk for metastatic renal cell carcinoma in targeted therapy era - a multi-institutional retrospective study

Background

This retrospective multicenter study aimed to evaluate the survival benefit of upfront cytoreductive nephrectomy (CN) in metastatic renal cell carcinoma (RCC) patients stratified by International Metastatic RCC Database Consortium (IMDC) risk criteria.

Methods

We reviewed the medical records in the Michinoku Database between 2008 and 2019. Patients who received upfront CN, systemic therapy without CN (no CN) and CN after drug therapy (deferred CN) were analyzed. To exclude selection bias due to patient characteristics, baseline clinical data were adjusted by inverse probability of treatment weighting (IPTW). Overall survival (OS) was compared between upfront CN and non-upfront CN (no CN plus deferred CN). Associations between time-varying covariates including systemic therapies and OS stratified by IMDC risk criteria were analyzed by IPTW-adjusted Cox regression method.

Results

Of 259 patients who fulfilled the selection criteria, 107 were classified in upfront CN and 152 in non-upfront CN group. After IPTW-adjusted analysis, upfront CN showed survival benefit compared to non-upfront CN in patients with IMDC intermediate risk (median OS: 52.5 versus 31.3 months, p < 0.01) and in patients with IMDC poor risk (27.2 versus 11.4 months, p < 0.01). In IPTW-adjusted Cox regression analysis of time-varying covariates, upfront CN was independently associated with OS benefit in patients with IMDC intermediate risk (hazard ratio 0.52, 95% confidence interval 0.29–0.93, p = 0.03) and in patients with IMDC poor risk (0.26, 0.11–0.59, p < 0.01).

Conclusions

Upfront CN may confer survival benefit in RCC patients with IMDC intermediate and poor risk.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10147-021-02091-8.

Nivolumab in metastatic renal cell carcinoma: results from the Turkish Oncology Group Kidney Cancer Consortium database

Aim: The authors present real-world data on the efficacy and safety of nivolumab in patients with metastatic renal cell carcinoma (mRCC). Methods: The Turkish Oncology Group Kidney Cancer Consortium (TKCC) database includes patients with mRCC from 13 cancer centers in Turkey. Patients with mRCC treated with nivolumab in the second line and beyond were extracted from the TKCC database. Results: A total of 173 patients were included. The rates of patients treated with nivolumab in the second, third, fourth and fifth lines were 47.4%, 32.4%, 14.5% and 5.7%, respectively. The median overall survival and progression-free survival were 24.2 months and 9.6 months, respectively. Nivolumab was discontinued owing to adverse events in 11 (6.4%) patients. Conclusion: Nivolumab was effective in patients with mRCC and no new safety signal was observed.

Outcomes of Stereotactic Radiosurgery and Immunotherapy in Renal Cell Carcinoma Patients With Brain Metastases

OBJECTIVE

The impact of immunotherapy and stereotactic radiosurgery (SRS) in treatment of brain metastases (BM) from renal cell carcinoma (RCC) has not been well investigated.

MATERIALS AND METHODS

Forty-eight patients with 372 RCC BM were treated with SRS and divided into those ever treated with immunotherapy versus those who never received immunotherapy. Survival and local control (LC) outcomes were studied. χ2 and Mann-Whitney U tests compared categorical and continuous variables, respectively. Kaplan-Meier curves were used to estimate survival and log-rank test was used to compare survival between groups.

RESULTS

Immunotherapy and nonimmunotherapy groups contained 29 and 19 patients, respectively. Median follow-up was 23.1 months (range, 6 to 93.8 mo). Demographic and treatment variables were similar except median prescribed margin dose was significantly lower in immunotherapy group (20 vs. 22 Gy, P<0.0001). Median overall survival (OS) was 27.2 months (immunotherapy) and 14.9 months (nonimmunotherapy), P=0.14. Furthermore, patients treated with immune checkpoint inhibitor (ICI) had even better median OS compared with those who never received ICI (33 vs. 16.7 mo, P=0.03). Factors associated with improved LC were use of ICI (P=0.002) and lesion size <1000 mm3 (P=0.046). There was no difference in incidence of radiation necrosis between the 2 groups (P=0.67).

CONCLUSIONS

Patients with RCC BM undergoing SRS can experience prolonged survival when treated with ICI. Equally effective LC of BM was achieved when treated with immunotherapy using a 2 Gy decrease in SRS dose without increasing the risk of central nervous system toxicity.

Validation of the updated renal graded prognostic assessment (GPA) for patients with renal cancer brain metastases treated with gamma knife radiosurgery

INTRODUCTION

Prognosis of patients with brain metastasis (BM) from renal cell carcinoma (RCC) is relevant for treatment decisions and can be estimated with the Renal Graded Prognostic Assessment (GPA). The aim of this study is to validate the updated version of this instrument in a cohort treated with Gamma Knife radiosurgery (GKRS) without prior local intracerebral therapy.

METHODS

Between 2007 and 2018, 106 RCC patients with BM were treated with GKRS. They were categorized according to the updated Renal GPA. Overall survival (OS), distant intracranial failure and local failure were estimated using the Kaplan-Meier method and risk factors were identified with Cox proportional hazard regressions.

RESULTS

Median OS was 8.6 months. Median OS for GPA categories 0.0-1.0 (15%), 1.5-2.0 (12%), 2.5-3.0 (35%) and 3.5-4.0 (29%) was 2.9, 5.5, 8.1 and 20.4 months, respectively. Karnofsky performance status < 90, serum hemoglobin ≤ 12.5 g/dL, age > 65 years and time from primary diagnosis to brain metastasis < 1 year were significantly related with shorter survival, while presence of extracranial disease, the volume and total number of BM had no significant impact on OS. A total count of > 4 BM was the only predictive factor for distant intracranial failure, while none of the investigated factors predicted local failure.

CONCLUSIONS

This study confirms the updated Renal GPA in an independent cohort as a valuable instrument to estimate survival in patients with BM from RCC treated with GKRS.

Radiotherapy and Renal Cell Carcinoma: A Continuing Saga

Renal cell carcinoma (RCC) is one of the most aggressive malignancies of the genito-urinary tract, having a poor prognosis especially in patients with metastasis. Surgical resection remains the gold standard for localized renal cancer disease, with radiotherapy (RT) receiving much skepticism during the last decades. However, many studies have evaluated the role of RT, and although renal cancer is traditionally considered radio-resistant, technological advances in the RT field with regards to modern linear accelerators, as well as advanced RT techniques have resulted in breakthrough therapeutic outcomes. Additionally, the combination of RT with immune checkpoint inhibitors and targeted agents may maximize the clinical benefit. This review article focuses on the role of RT in the therapeutic management of renal cell carcinoma.

Prognostic Factors and Current Treatment Strategies for Renal Cell Carcinoma Metastatic to the Brain: An Overview

Renal cell carcinoma (RCC) is one of primary cancers that frequently metastasize to the brain. Brain metastasis derived from RCC has the propensity of intratumoral hemorrhage and relatively massive surrounding edema. Moreover, it confers a grim prognosis in a great percentage of cases with a median overall survical (mOS) around 10 months. The well-recognized prognostic factors for brain metastatic renal cell carcinoma (BMRCC) are Karnofsky Performance Status (KPS), the number of brain metastasis (BM), the presence of a sarcomatoid component and the presence of extracranial metastasis. Therapeutic strategies are multimodal and include surgical resection, radiotherapy, such as stereotactic radiosurgery due to the radioresistance of RCC and systemic strategies with tyrosin kinase inhibitors (TKI) or Immune checkpoint inhibitors (ICI) whose efficacy is not well-established in this setting of patients due to their exclusion from most clinical trials. To date, in case of positive prognostic factors and after performing local radical therapies, such as complete resection of BM or stereotactic radiosurgery (SRS), the outcome of these patients significantly improves, up to 33 months in some patients. As a consequence, tailored clinical trials designed for BMRCC are needed to define the correct treatment strategy even in this poor prognostic subgroup of patients.

Oligo metastatic renal cell carcinoma: stereotactic body radiation therapy, if, when and how?

BACKGROUND AND PURPOSE

Renal cell carcinoma (RCC) has traditionally been considered radioresistant with a limited role for conventional fractionation as a local approach. Nevertheless, since the appearance of stereotactic body radiation therapy (SBRT), radiotherapy (RT) has been increasingly employed in the management of metastatic RCC (mRCC). The aim of this study was to evaluate the role of SBRT for synchronous and metachronous oligo metastatic RCC patients in terms of local control, delay of systemic treatment, overall survival and toxicity.

PATIENTS AND METHODS

A Monocentric single institution retrospective data collection was performed. Inclusion criteria were: (1) oligo-recurrent or oligo-progressive disease (less than 5 metastases) in mRCC patients after radical/partial nephrectomy or during systemic therapy, (2) metastasectomy or other metastasis-directed, rather than SBRT not feasible, (3) any contraindication to receive systemic therapy (such as comorbidities), (4) all the histologies were included, (5) available signed informed consent form for treatment. Tumor response and toxicity were evaluated using the response evaluation criteria in solid tumors and the Common Terminology Criteria for Adverse Events version 4.03, respectively. Progression-free survival in-field and out-field (in-field and out-field PFS) and overall survival (OS) were calculated via the Kaplan-Meier method. The drug treatment-free interval was calculated from the start of SBRT to the beginning of any systemic therapy.

RESULTS

From 2010 to December 2018, 61 patients with extracranial and intracranial metastatic RCC underwent SBRT on 83 lesions. Intracranial and extracranial lesions were included. Forty-five (74%) patients were treated for a solitary metastatic lesion. Median RT dose was 25 Gy (range 10-52) in 5-10 fractions. With a median follow-up of 2.3 years (range 0-7.15), 1-year in-field PFS was 70%, 2-year in-field PFS was 55%. One year out-field PFS was 39% and 1-year OS was 78%. Concomitant systemic therapy was employed for only 11 (18%) patients, for the others 50 (82%) the drug treatment-free rate was 70% and 50% at 1 and 2 years, respectively. No > G1 acute and late toxicities were reported.

CONCLUSION

The pattern of failure was pre-dominantly out-of-field, even if the population was negatively selected and the used RT dose could be considered palliative. Therefore, SBRT appears to be a well-tolerated, feasible and safe approach in oligo metastatic RCC patients with an excellent in-field PFS. SBRT might play a role in the management of selected RCC patients allowing for a delay systemic therapy begin (one out of two patients were free from new systemic therapy at 2 years after SBRT). Further research on SBRT dose escalation is warranted.

Current Multimodality Treatments Against Brain Metastases from Renal Cell Carcinoma

Simple Summary

Brain metastasis (BM) is generally one of poor prognostic factors in patients with advanced renal cell carcinoma. However, because of longer control of extra-cranial disease by the recent introduction of molecular target therapy and immune checkpoint inhibitor, the incidence of BM has been recently increasing and to progress the treatment of BM is one of urgent medical unmet needs. Although the pivotal clinical trials usually excluded patients with BM, BM subgroup data from the prospective and retrospective series have been gradually accumulated. To select the appropriate strategy, individual patient and tumor characteristics (e.g., Karnofsky Performance Status (KPS), systemic cancer burden, the number/size/location of BM) are important information. Among the local treatments, the technology of stereotactic radiosurgery (SRT) has been especially advanced and its adaptation has been expanded. The combination of SRT with molecular target therapy and/or immune checkpoint inhibitor would be promising to further enhance the efficacy without increased toxicity.

Abstract

In patients with renal cell carcinoma, brain metastasis is generally one of the poor prognostic factors. However, the recent introduction of molecular target therapy and immune checkpoint inhibitor has remarkably advanced the systemic treatment of metastatic renal cell carcinoma and prolonged the patients’ survival. The pivotal clinical trials of those agents usually excluded patients with brain metastasis. The incidence of brain metastasis has been increasing in the actual clinical setting because of longer control of extra-cranial disease. Brain metastasis subgroup data from the prospective and retrospective series have been gradually accumulated about the risk classification of brain metastasis and the efficacy and safety of those new agents for brain metastasis. While the local treatment against brain metastasis includes neurosurgery, stereotactic radiosurgery, and conventional whole brain radiation therapy, the technology of stereotactic radiosurgery has been especially advanced, and the combination with systemic therapy such as molecular target therapy and immune checkpoint inhibitor is considered promising. This review summarizes recent progression of multimodality treatment of brain metastasis of renal cell carcinoma from literature data and explores the future direction of the treatment.

Impact of Tyrosine Kinase Inhibitors (TKIs) Combined With Radiation Therapy for the Management of Brain Metastases From Renal Cell Carcinoma

Background: Targeted therapy has transformed the outcome for patients with metastatic renal cell carcinoma. Their efficacy and safety have also been demonstrated in brain metastatic RCC. Preclinical evidence suggests synergism of radiation and tyrosine kinase inhibitors. Consequently, several studies have compared their efficacy in the treatment of RCC brain metastases to the era of brain management with surgery/radiation only.

Objectives: We seek to systematically review and meta-analyze the results of those studies that involved comparative intervention groups of brain management; TKIs, and never used TKIs.

Methods and Materials: Online databases (PubMed, EMBASE, Cochrane library, and ClinicalTrials.gov) were searched for comparative studies. Overall survival as the primary outcome of interest, and local brain control, distant control, and adverse events as secondary outcomes of interest were recorded for meta-analysis. Hazard ratios were pooled together using Review Manager 5.3. Fixed effects or random effects model were adopted according to the level of heterogeneity. Subgroup analysis included studies that involved SRS as the local treatment of management.

Results: Overall 7 studies (n = 897) were included for meta-analysis. TKI use was associated with better survival (HR 0.60 [0.52, 0.69], p < 0.00001) and local brain control (HR 0.34 [0.11, 0.98], p = 0.05). SRS subgroup also revealed significantly better survival (HR 0.61 [0.44, 0.83], p = 0.002) and local brain control (HR 0.19 [0.08, 0.45], p = 0.0002). Distant brain control (HR 0.95 [0.67, 1.35], p = 0.79) and brain progression free survival were unaffected (HR 0.94 [0.56, 1.56], p = 0.80). Only one study (n = 376) reported significantly greater 12-months cumulative incidence of radiation necrosis with TKI use within 30 days of SRS (10.9 vs. 6.4%, p = 0.04).

Conclusions: TKIs use in combination with SRS is safe and effective for treating RCC brain metastases. Larger randomized controlled trials are warranted to validate the results.

Tumor Primary Site and Histology Subtypes Role in Radiotherapeutic Management of Brain Metastases

Randomized controlled trials have failed to report any survival advantage for WBRT combined with SRS in the management of brain metastases, despite the enhanced local and distant control in comparison to each treatment alone. Literature review have revealed important role of primary histology of the tumor when dealing with brain metastases. NSCLC responds better to combined approach even when there was only single brain metastasis present while breast cancer has registered better survival with SRS alone probably due to better response of primary tumor to advancement in surgical and chemotherapeutic agents. Furthermore, mutation status (EGFR/ALK) in lung cancer and receptor status (ER/PR/HER2) in breast cancer also exhibit diversity in their response to radiotherapy. Radioresistant tumors like renal cell carcinoma and melanoma brain metastases have achieved better results when treated with SRS alone. Secondly, single brain metastasis may benefit from local and distant brain control achieved with combined treatment. These diverse outcomes suggest a primary histology-based analysis of the radiotherapy regimens (WBRT, SRS, or their combination) would more ideally establish the role of radiotherapy in the management of brain metastases. Molecularly targeted therapeutic and immunotherapeutic agents have revealed synergism with radiation therapy particularly SRS in treating cancer patients with brain metastases. Clinical updates in this regard have also been reviewed.

Clinical Outcomes in Patients with Renal Cell Carcinoma Metastases to the Choroid Plexus

OBJECTIVE

Intraventricular metastatic brain tumors account for a small, but challenging, fraction of metastatic brain tumors (0.9%-4.5%). Metastases from renal cell carcinoma (RCC) account for a large portion of these intraventricular tumors. Although patient outcomes have been assumed to be poor, these have not been reported in a modern series with a multimodality treatment paradigm of radiotherapy (RT), resection, and cerebrospinal fluid (CSF) diversion. We have presented the first case series of patients with intraventricular metastatic tumors from RCC.

METHODS

We performed a single-institution retrospective review of patients with intraventricular RCC metastases treated from January 2003 to January 2019. Volumetric analysis was used to delineate the tumor size and the Kaplan-Meier method to evaluate the survival data.

RESULTS

A total of 22 intraventricular RCC metastases were identified in 19 patients with 61.3 patient-years of follow-up. The median patient age was 64 years, and the median tumor volume was 2.2 cm³. Overall, 19 metastases had been treated initially with RT. Of these, 16 had received stereotactic body RT and 3 had received whole brain RT. Three tumors were surgically excised and had received adjuvant stereotactic body RT in the upfront setting. Although 5 patients had presented with obstructive hydrocephalus, none had required CSF diversion. After treatment, 5 metastases had progressed, resulting in 1- and 3-year progression-free survival rates of 81.6% and 68%, respectively. The median overall survival was 2.8 years, with 1- and 5-year overall survival rates of 76.7% and 28.3%, respectively. Leptomeningeal carcinomatosis was not observed.

CONCLUSIONS

Despite the relatively limited overall survival for this population with metastatic cancer, comparable to contemporary parenchymal brain metastasis cohorts, reasonable local central nervous system control was achieved in most patients using a paradigm of focal RT and resection, where indicated. Finally, CSF diversion was not required even in patients presenting with hydrocephalus.

Overall survival and response to radiation and targeted therapies among patients with renal cell carcinoma brain metastases

OBJECTIVE

The object of this retrospective study was to investigate the impact of targeted therapies on overall survival (OS), distant intracranial failure, local failure, and radiation necrosis among patients treated with radiation therapy for renal cell carcinoma (RCC) metastases to the brain.

METHODS

All patients diagnosed with RCC brain metastasis (BM) between 1998 and 2015 at a single institution were included in this study. The primary outcome was OS, and secondary outcomes included local failure, distant intracranial failure, and radiation necrosis. The timing of targeted therapies was recorded. Multivariate Cox proportional-hazards regression was used to model OS, while multivariate competing-risks regression was used to model local failure, distant intracranial failure, and radiation necrosis, with death as a competing risk.

RESULTS

Three hundred seventy-six patients presented with 912 RCC BMs. Median OS was 9.7 months. Consistent with the previously validated diagnosis-specific graded prognostic assessment (DS-GPA) for RCC BM, Karnofsky Performance Status (KPS) and number of BMs were the only factors prognostic for OS. One hundred forty-seven patients (39%) received vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKIs). Median OS was significantly greater among patients receiving TKIs (16.8 vs 7.3 months, p < 0.001). Following multivariate analysis, KPS, number of metastases, and TKI use remained significantly associated with OS.The crude incidence of local failure was 14.9%, with a 12-month cumulative incidence of 13.4%. TKIs did not significantly decrease the 12-month cumulative incidence of local failure (11.4% vs 14.5%, p = 0.11). Following multivariate analysis, age, number of BMs, and lesion size remained associated with local failure. The 12-month cumulative incidence of radiation necrosis was 8.0%. Use of TKIs within 30 days of SRS was associated with a significantly increased 12-month cumulative incidence of radiation necrosis (10.9% vs 6.4%, p = 0.04).

CONCLUSIONS

Use of targeted therapies in patients with RCC BM treated with intracranial SRS was associated with improved OS. However, the use of TKIs within 30 days of SRS increases the rate of radiation necrosis without improving local control or reducing distant intracranial failure. Prospective studies are warranted to determine the optimal timing to reduce the rate of necrosis without detracting from survival.

Operative and peri-operative considerations in the management of brain metastasis

The number of patients who develop metastatic brain lesions is increasing as the diagnosis and treatment of systemic cancers continues to improve, resulting in longer patient survival. The role of surgery in the management of brain metastasis (BM), particularly multiple and recurrent metastases, remains controversial and continues to evolve. However, with appropriate patient selection, outcomes after surgery are typically favorable. In addition, surgery is the only means to obtain a tissue diagnosis and is the only effective treatment modality to quickly relieve neurological complications or life-threatening symptoms related to significant mass effect, CSF obstruction, and peritumoral edema. As such, a thorough understanding of the role of surgery in patients with metastatic brain lesions, as well as the factors associated with surgical outcomes, is essential for the effective management of this unique and growing patient population.

Is there a role for stereotactic radiotherapy in the treatment of renal cell carcinoma?

Renal cell carcinoma (RCC) has traditionally been regarded as radioresistant tumor based on preclinical data and negative clinical trials using conventional fractionated radiotherapy. However, there is emerging evidence that radiotherapy delivered in few fractions with high single-fraction and total doses may overcome RCC s radioresistance. Stereotactic radiotherapy (SRT) has been successfully used in the treatment of intra- and extracranial RCC metastases showing high local control rates accompanied by low toxicity. Although surgery is standard of care for non-metastasized RCC, a significant number of patients is medically inoperable or refuse surgery. Alternative local approaches such as radiofrequency ablation or cryoablation are invasive and often restricted to small RCC, so that there is a need for alternative local therapies such as stereotactic body radiotherapy (SBRT). Recently, both retrospective and prospective trials demonstrated that SBRT is an attractive treatment alternative for localized RCC. Here, we present a comprehensive review of the published data regarding SBRT for primary RCC. The radiobiological rationale to use higher radiation doses in few fractions is discussed, and technical aspects enabling the safe delivery of SBRT despite intra- and inter-fraction motion and the proximity to organs at risk are outlined.

Intraoperative brachytherapy for resected brain metastases

Brain metastases are the most common intracranial malignancies in adults. Surgical resection is the preferred treatment approach when a pathological diagnosis is required, for symptomatic patients who are refractory to steroids, and to decompress lesions causing mass effect. Radiotherapy is administered to improve local control rates after surgical resection. After a brief review of the literature describing the treatment of brain metastases using whole-brain radiotherapy, postoperative stereotactic radiosurgery, preoperative radiosurgery, and brachytherapy, we compare patient-related, technical, practical, and radiobiological considerations of each technique. Finally, we focus our discussion on intraoperative brachytherapy, with an emphasis on the technical aspects, benefits, efficacy, and outcomes of studies utilizing permanent Cs-131 implants.

Efficacy of gamma knife radiosurgery in brain metastases of primary gynecological tumors

OBJECTIVE

Gynecological brain metastases (BM) are rare and usually develop as part of widespread disseminated disease. Despite treatment, the majority of these patients do not survive > 1 year due to advanced extracranial disease. The use of Gamma Knife Radiosurgery (GKRS) for gynecological BM is not well known. The goal of this study is to evaluate the efficacy of GKRS for gynecological BM.

METHODS

We performed a retrospective study of patients with gynecological BM who underwent GKRS between 2002 and 2015. A total of 41 patients were included. Outcome measures were local tumor control (LC), development of new BM and/or leptomeningeal disease, overall intracranial progression free survival (PFS) and survival.

RESULTS

LC was 100%, 92%, 80%, 75% and 67% at 3, 6, 9, 12 and 15 months, respectively. PFS was 90%, 61%, 41%, 23% and 13% at 3, 6, 9, 12 and 15 months, respectively. During follow-up (FU), 18 (44%) patients had intracranial progression. Distant BM occurred in 29% of the patients. Local recurrence and distant recurrence occurred after a mean FU time of 15.5 (2.6-71.9) and 11.4 (2-40) months, respectively. Thirty-one (76%) patients died due to extracranial tumor progression and only 2 (5%) patients died due to progressive intracranial disease. The overall mean survival from time of GKRS was 19 months (1-109). The 6-month, 1-year, and 2-year survival rate from the time of GKRS were 71%, 46%, and 22%, respectively.

CONCLUSION

GKRS is a good treatment option for controlling gynecological BM. As most patients die due to extracranial tumor progression, their survival might improve with better systemic treatment options in addition to GKRS.

The influence of histology on the response of brain metastases to gamma knife radiosurgery: a propensity score-matched study

BACKGROUND

In terms of response to fractionated radiotherapy, metastatic brain tumors of certain origins are considered radioresistant.

OBJECTIVE

To determine the influence of "radioresistant" histology on outcomes of brain metastases treated with radiosurgery.

METHODS

Between 2001 and 2017, 121 patients with brain metastases from renal cell carcinoma (RCC) and 2151 from non-small cell lung cancer (NSCLC) were reviewed. Eighty-seven pairs were derived using propensity score matching. Local progression-free survival (PFS), progression patterns, distant PFS, and overall survival were investigated.

RESULTS

The median follow-up period was 13.7 months (range, 1.6-78.4 months). A total of 536 lesions were treated using gamma knife radiosurgery (GKS), with a median dose of 20 Gy (range, 12-28 Gy). The actuarial local PFS rates in the RCC group were 91% and 89% at 6 and 12 months, respectively, and did not differ from the NSCLC group (97% and 83% at 6 and 12 months, respectively). Continuous progression, without response to GKS, was noted in seven of the eight progressed RCCs. However, six of the seven progressed NSCLCs showed transient shrinkage before progression. The median distant PFS was 9.3 months (95% CI, 6.3-12.2) in the RCC group and 8.0 months (95% CI, 5.5-10.4) in the NSCLC group. The median overall survival was 16.1 months (95% CI, 11.3-20.8) and 14.9 months (95% CI, 11.9-17.8) in RCC and NSCLC groups, respectively.

CONCLUSION

Histological differences had no effect on local control in the single high-dose range used for radiosurgery. However, changes in tumor volume during progression varied across tumor histology.

Improving the Prognostic Value of Disease-Specific Graded Prognostic Assessment Model for Renal Cell Carcinoma by Incorporation of Cumulative Intracranial Tumor Volume

BACKGROUND

We tested the prognostic value of cumulative intracranial tumor volume (CITV) in the context of a disease-specific Graded Prognostic Assessment (ds-GPA) model for renal cell carcinoma (RCC) patients with brain metastasis (BM) treated with stereotactic radiosurgery (SRS).

METHODS

Patient and tumor characteristics were collected from RCC cohorts with new BM who underwent SRS. Univariable and multivariable logistic regression model was used to test the prognostic value of CITV, Karnofsky Performance Score (KPS), and the number of BM. Net reclassification index (NRI) and integrated discrimination improvement (IDI) were used to assess whether CITV improved the prognostic utility of RCC ds-GPA.

RESULTS

In univariable logistic regression models, CITV, KPS, and the number of BM were independently associated with RCC patient survival. In a multivariable Cox proportional hazard model, the association between CITV and survival remained robust after controlling for KPS and the number of BM (P = 0.042). The incorporation of the CITV into the RCC ds-GPA model (consisting of KPS and number of BM) improved prognostic accuracy with NRI >0 of 0.3156 (95% confidence interval [CI], 0.0883-0.5428; P = 0.0065) and IDI of 0.0151 (95% CI, 0.0036-0.0277; P = 0.0183). These findings were validated in an independent cohort of 107 SRS-treated RCC BM patients.

CONCLUSION

CITV is an important prognostic variable in SRS-treated RCC patients with BM. The prognostic value of the ds-GPA scale for RCC brain metastasis was enhanced by the incorporation of CITV.

Surgical Management of Advanced and Metastatic Renal Cell Carcinoma: A Multidisciplinary Approach

The past decade has seen a rapid proliferation in the number and types of systemic therapies available for renal cell carcinoma. However, surgery remains an integral component of the therapeutic armamentarium for advanced and metastatic kidney cancer. Cytoreductive surgery followed by adjuvant cytokine-based immunotherapy (predominantly high-dose interleukin 2) has largely given way to systemic-targeted therapies. Metastasectomy also has a role in carefully selected patients. Additionally, neoadjuvant systemic therapy may increase the feasibility of resecting the primary tumor, which may be beneficial for patients with locally advanced or metastatic disease. Several prospective trials examining the role of adjuvant therapy are underway. Lastly, the first immune checkpoint inhibitor was approved for metastatic renal cell carcinoma (mRCC) in 2015, providing a new treatment mechanism and new opportunities for combining systemic therapy with surgery. This review discusses current and historical literature regarding the surgical management of patients with advanced and mRCC and explores approaches for optimizing patient selection.

Prognostic Factors for Survival of Patients With Synchronous or Metachronous Brain Metastasis of Renal Cell Carcinoma

INTRODUCTION

We evaluated the oncological outcomes of synchronous or metachronous brain metastasis (BM) of metastatic renal cell carcinoma (RCC) according to clinicopathologic factors.

PATIENTS AND METHODS

Patients with metastatic RCC (n = 93) with synchronous and metachronous BM were retrospectively identified. We analyzed patients and tumor characteristics, treatment methods, prognostic factors, BM progression, and overall survival (OS).

RESULTS

Seventy-six patients (81.7%) received local therapy (stereotactic radiosurgery [60.2%], radiation therapy [22.6%], and neurosurgery [10.8%]), and 54 patients (58.1%) were treated with systemic medical therapy. In multivariable analysis, poor Memorial Sloan-Kettering Cancer Center (MSKCC) risk (hazard ratio [HR] 3.672; 95% confidence interval [CI], 1.441-9.36; P = .0064), sarcomatoid component (HR 4.264; 95% CI, 2.062-8.820; P = .0001), and multiple BMs (HR 2.838; 95% CI, 1.690-4.767; P = .0001) were prognostic indicators of a poorer OS outcome. Local (HR 0.436; 95% CI, 0.237-0.802; P = .0076) and systemic treatment (HR 0.322; 95% CI, 0.190-0.548; P < .0001) were independent factors for a better OS. Although OS from initial RCC diagnosis in patients with metachronous BM was better than that for patients with synchronous BM, there were no differences found between synchronous and metachronous patients in terms of BM progression and OS after the diagnosis of BM.

CONCLUSIONS

Poor MSKCC risk, sarcomatoid component of histology, and multiple BMs are prognostic indicators for poor OS in patients with BM from metastatic RCC. Systemic and/or local treatment improves the OS. Because the type of BM, synchronous or metachronous, does not influence BM progression or the OS outcome, routine evaluation for BM is not recommended.

Simultaneous meningioma and brain metastasis from renal cell carcinoma - a rare presentation. Case report

CONTEXT:

Brain metastases are the most common tumors of the central nervous system. Because of their high frequency, they may be associated with rare situations. Among these are tumor-to-tumor metastasis and an even a rarer situation called simultaneous brain tumors, which are more related to primary tumors of the reproductive and endocrine systems.

CASE REPORT:

A 56-year-old male patient with a history of renal cell carcinoma (which had previously been resected) presented with a ventricular lesion (suggestive of metastatic origin) and simultaneous olfactory groove lesion (probably a meningioma). First, only the ventricular lesion was dealt with, but after a year, the meningothelial lesion increased and an occipital lesion appeared. Therefore, both of these were resected in a single operation. All the procedures were performed by the same neurosurgeon. The patient evolved without neurological deficits during the postoperative period. After these two interventions, the patient remained well and was referred for adjuvant treatment.

CONCLUSIONS:

This study provides the first description of an association between these two tumors. Brain metastases may be associated with several lesions, and rare presentations such as simultaneity with meningioma should alert neurosurgeons to provide the best oncological treatment.

Radiosurgery in the management of brain metastasis: a retrospective single-center study comparing Gamma Knife and LINAC treatment

OBJECTIVE The authors present a retrospective analysis of a single-center experience with treatment of brain metastases using Gamma Knife (GK) and linear accelerator (LINAC)-based radiosurgery and compare the results. METHODS From July 2010 to July 2012, 63 patients with brain metastases were treated with radiosurgery. Among them, 28 (with 83 lesions) were treated with a GK unit and 35 (with 47 lesions) with a LINAC. The primary outcome was local progression-free survival (LPFS), evaluated on a per-lesion basis. The secondary outcome was overall survival (OS), evaluated per patient. Statistical analysis included standard tests and Cox regression with shared-frailty models to account for the within-patient correlation. RESULTS The mean follow-up period was 11.7 months (median 7.9 months, range 1.7-32 months) for GK and 18.1 months (median 17 months, range 7.5-28.7 months) for LINAC. The median number of lesions per patient was 2.5 (range 1-9) in the GK group and 1 (range 1-3) in the LINAC group (p < 0.01, 2-sample t-test). There were more radioresistant lesions (e.g., melanoma) and more lesions located in functional areas in the GK group. Additional technical reasons for choosing GK instead of LINAC were limitations of LINAC movements, especially if lesions were located in the lower posterior fossa or multiple lesions were close to highly functional areas (e.g., the brainstem), precluding optimal dosimetry with LINAC. The median marginal dose was 24 Gy with GK and 20 Gy with LINAC (p < 0.01, 2-sample t-test). For GK, the actuarial LPFS rate at 3, 6, 9, 12, and 17 months was 96.96%, 96.96%, 96.96%, 88.1%, and 81.5%, remaining stable until 32 months. For LINAC the rate at 3, 6, 12, 17, 24, and 33 months was 91.5%, 91.5%, 91.5%, 79.9%, 55.5%, and 17.1% (log-rank p = 0.03). In the Cox regression with shared-frailty model, the risk of local progression in the LINAC group was almost twice that of the GK group (HR 1.92, p > 0.05). The mean OS was 16.0 months (95% CI 11.2-20.9 months) in the GK group, compared with 20.9 months (95% CI 16.4-25.3 months) in the LINAC group. Univariate and multivariate analysis showed that a lower graded prognostic assessment (GPA) score, noncontrolled systemic status at last radiological assessment, and older age were associated with lower OS; after adjustment of these covariables by Cox regression, the OS was similar in the 2 groups. CONCLUSIONS In this retrospective study comparing GK and LINAC-based radiosurgery for brain metastases, patients with more severe disease were treated by GK, including those harboring lesions of greater number, of radioresistant type, or in highly functional areas. The risk of local progression for the LINAC group was almost twice that in the GK group, although the difference was not statistically significant. Importantly, the OS rates were similar for the 2 groups, although GK was used in patients with more complex brain metastatic disease and with no other therapeutic alternative.

Evaluating the impact of hippocampal sparing during whole brain radiotherapy on neurocognitive functions: A preliminary report of a prospective phase II study

BACKGROUND

Whole brain radiotherapy (WBRT) is the treatment of choice for patients with brain metastases. However, neurocognitive functions (NCFs) decline due to impaired hippocampal neurogenesis might occur thereafter. It is hypothesized that conformal hippocampal avoidance during the course of WBRT (HA-WBRT) might provide meaningful NCF preservation. Our study aims to demonstrate the impact of delivering HA-WBRT on NCF changes in patients receiving WBRT.

METHODS

Twenty-five patients who were referred for prophylactic cranial irradiation (PCI) or treating oligometastatic brain disease were enrolled in the study. Before the HA-WBRT course, all participants should receive baseline neurocognitive assessment, including memory, executive functions, and psychomotor speed. The primary endpoint was delayed recall, as determined by the change/decline in verbal memory [Wechsler Memory Scale - 3rd edition (WMS III)- Word List score] from the baseline assessment to 4 months after the start of HA-WBRT.

RESULTS

Only three patients belonged to the clinical setting of PCI; the remaining 22 patients had oligometastatic brain disease. Regarding neurocognitive outcomes, no statistically significant differences were found between various NCF scores obtained at baseline and at post-radiotherapy intervals, in immediate verbal memory and non-verbal memory, except for delayed recall memory on Word List (F = 5.727, p = 0.048).

CONCLUSIONS

Functional preservation by hippocampal sparing during WBRT could largely be achieved in this study, which also suggests that HA-WBRT should be a feasible technique preserving neurocognitive functions while maintaining intracranial control.

Surgical Resection of Cerebral Metastases Leads to Faster Resolution of Peritumoral Edema than Stereotactic Radiosurgery: A Volumetric Analysis

BACKGROUND

Surgical resection and stereotactic radiosurgery (SRS) are well-established treatment options for selected patients with oligo-brain metastases (BMs). The dynamics of edema resolution with each treatment method have not been well characterized.

METHODS

Of 389 patients treated for BMs between 2012 and 2014, this study retrospectively identified 107 patients (150 metastases) who underwent either surgery or SRS as a single treatment method for BMs. The two groups of patients were matched for clinical parameters. Volumetric assessments of the tumor and associated edema were performed before treatment and then 2-3 months after treatment.

RESULTS

In this study, 76 surgical cases were compared with 74 cases treated with SRS. The volume of the tumor and surrounding edema was significantly greater in the surgery group than in the SRS group. However, resolution of edema was significantly more rapid in the surgical group (p < 0.0001), accompanied by faster weaning from steroids. After a matching process based on the propensity of a patient to receive SRS, a subgroup cohort was analyzed (mean maximal diameter: 21 mm in the surgical group vs 20.8 mm in the SRS group; p = 0.9). At diagnosis, edema volume, but not tumor volume, was significantly greater in the surgical group. The resolution of edema 2-3 months after treatment was better in the surgical group than in the SRS group (89.6% vs 71.1% of baseline, respectively; p = 0.09), although this difference did not reach the level of significance.

CONCLUSIONS

Resolution of tumor-associated edema in BMs suitable for either surgery or SRS was significantly faster after surgical resection than after SRS. Accordingly, when both treatment options are suitable, surgery appears to induce faster resolution of the edema.

Multimodality treatment of brain metastases from renal cell carcinoma in the era of targeted therapy

In patients with renal cancer, brain metastasis is associated with poor survival and high morbidity. Poor life expectancy is often associated with widespread extracranial metastases. In such patients, a multidisciplinary approach is paramount. Brain metastases-specific therapies may include surgery, radiosurgery, conventional radiation and targeted therapies (TT) or a combination of these treatments. Some factors are important prognostically when choosing the best strategy: performance status, the number, size and location of brain metastases, the extension of systemic metastases and a well-controlled primary tumour. Failure of chemical therapy has always been attributed to an intact blood-brain barrier and acquired drug resistance by renal cancer cells. Recent studies have demonstrated objective responses with TT in a variety of cancer types, including renal cancer. In most cases, these agents have been used in combination and in conjunction with whole-brain radiation therapy and radiosurgery. Local control appears to be better with the combined method if the patient has a good performance status and may improve overall survival. This review summarizes current literature data on multidisciplinary approach in the management of renal brain metastasis with radiation, surgery and TT with an emphasis on potential better outcomes with a combination of current treatment methods.

Treatment of brain metastases in the modern genomic era

Development of brain metastasis (BM) portends a dismal prognosis for patients with cancer. Melanomas and carcinomas of the lung, breast, and kidney are the most common malignancies to metastasize to the brain. Recent advances in molecular genetics have enabled the identification of actionable, clinically relevant genetic alterations within primary tumors and their corresponding metastases. Adoption of genotype-guided treatment strategies for the management of systemic malignancy has resulted in dramatic and durable responses. Unfortunately, despite these therapeutic advances, central nervous system (CNS) relapses are not uncommon. Although these relapses have historically been attributed to limited blood brain barrier penetration of anti-neoplastic agents, recent work has demonstrated genetic heterogeneity such that metastatic sites, including BM, harbor relevant genetic alterations that are not present in primary tumor biopsies. This improved insight into molecular mechanisms underlying site specific recurrences can inform strategies for targeting these oncogenic drivers. Thus, development of rational, genomically guided CNS-penetrant therapies is crucial for ongoing therapeutic success.

Retrospective Study of Metastatic Melanoma and Renal Cell Carcinoma to the Brain with Multivariate Analysis of Prognostic Pre-Treatment Clinical Factors

Patients with brain metastasis from renal cell carcinoma (RCC) or melanoma have historically had very poor prognoses of less than one year. Stereotactic radiosurgery (SRS) can be an effective treatment for patients with these tumors. This study analyzes the effect of pretreatment prognostic factors on overall survival (OS) for RCC and melanoma patients with metastasis to the brain treated with SRS. A total of 122 patients with brain metastases from either RCC or melanoma were grouped by age at brain metastasis diagnosis, whether they received whole brain radiation therapy (WBRT) in addition to SRS, or they underwent surgical resection, Karnofsky Performance Score (KPS), number of brain metastases, and primary tumor. Median survival times for melanoma patients and RCC patients were 8.20 ± 3.06 and 12.70 ± 2.63 months, respectively. Patients with >5 metastases had a significantly shorter median survival time (6.60 ± 2.45 months) than the reference group (1 metastasis, 10.70 ± 13.40 months, p = 0.024). Patients with KPS ≤ 60 experienced significantly shorter survival than the reference group (KPS = 90–100), with median survival times of 5.80 ± 2.46 months (p < 0.001) and 45.20 ± 43.52 months, respectively. We found a median overall survival time of 12.7 and 8.2 months for RCC and melanoma, respectively. Our study determined that a higher number of brain metastases (>5) and lower KPS were statistically significant predictors of a lower OS prognosis.

Clinical Outcome of Third-Line Pazopanib in a Patient with Metastatic Renal Cell Carcinoma

Background. Renal cell carcinoma accounts for about 2-3% of all malignant tumors. The prevalence of brain metastases from RCC is less than 20% of cases. Traditionally, whole brain radiotherapy as well as the latest stereotactic radiosurgery improves both survival and local tumor control. These treatments also allow stabilization of clinical symptomatology. However, validated treatment guidelines for RCC patients with brain metastases are not yet available on account of the frequent exclusion of such patients from clinical trials. Moreover, limited data about the sequential use of three therapies, changing the class of agent, have been published up to now. Case Report. We report the case of a patient with metastatic RCC who developed disease progression after sunitinib and everolimus as first-line and second-line therapy, respectively. Thus, he underwent a multimodality treatment with pazopanib, as third-line therapy, to control systemic disease and radiosurgery directed on the new brain metastasis. To date, the patient is still receiving pazopanib, with progression-free survival and overall survival of 43 and 103 months, respectively. Conclusion. In a context characterized by different emerging options, with no general consensus on the optimal treatment strategy, the use of pazopanib in pretreated patients could be a suitable choice.

Prolonged Survival following Repetitive Stereotactic Radiosurgery in a Patient with Intracranial Metastatic Renal Cell Carcinoma

Patients with metastatic renal cell carcinoma (RCC) to the brain have a very poor prognosis of three months if left untreated. SRS is an effective treatment modality in numerous patients. This case exemplifies the utility of stereotactic radiosurgery (SRS) in prolonging survival and maintaining quality of life in a patient with RCC. This 64-year-old female patient initially presented to her primary care physician 22 months after a left nephrectomy for RCC with complaints of mild, intermittent headaches and difficulty with balance. An MRI revealed five cerebellar lesions suspicious for intracranial metastasis. The patient's first GKRS treatment targeted four lesions with 22 Gy at the 50% isodose line. She underwent a total of seven GKRS treatments over the next 60 months for recurrent metastases to the brain. 72 months and 12 months have now passed since her brain metastases were first discovered and since her last GKRS treatment, respectively, and this woman is alive with considerable quality of life and no evidence of metastatic reoccurrence. This case shows that repeated GKRS treatments, with minimal surgical intervention, can effectively treat multiple intracranial lesions in select patients, prolonging survival and avoiding iatrogenic neurocognitive decline while maintaining a high quality of life.

Stereotactic Radiosurgery for Renal Cancer Brain Metastasis: Prognostic Factors and the Role of Whole-Brain Radiation and Surgical Resection

Background. Renal cell carcinoma is a frequent source of brain metastasis. We present our consecutive series of patients treated with Stereotactic Radiosurgery (SRS) and analyse prognostic factors and the interplay of WBRT and surgical resection. Methods. This is a retrospective study of 66 patients with 207 lesions treated with the Cyberknife radiosurgery system in our institution. The patients were followed up with imaging and clinical examination 1 month and 2-3 months thereafter for the brain metastasis. Patient, treatment, and outcomes characteristics were analysed. Results. 51 male (77.3%) and 15 female (22.7%) patients, with a mean age of 58.9 years (range of 31–85 years) and a median Karnofsky Performance Status (KPS) of 90 (range of 60–100), were included in the study. The overall survival was 13.9 months, 21.9 months, and 5.9 months for the patients treated with SRS only, additional surgery, and WBRT, respectively. The actuarial 1-year Local Control rates were 84%, 94%, and 88% for SRS only, for surgery and SRS, and for WBRT and additional SRS, respectively. Conclusions. Stereotactic radiosurgery is a safe and effective treatment option in patients with brain metastases from RCC. In case of a limited number of brain metastases, surgery and SRS might be appropriate.

Early identification of asymptomatic brain metastases from renal cell carcinoma

Current guidelines for metastatic renal cell carcinoma (mRCC) do not recommend routine brain imaging as part of the surveillance protocol unless central nervous system (CNS) symptoms or abnormal laboratory values suggest brain involvement. We hypothesized that strict adherence to these guidelines will delay diagnosis and management of RCC brain metastases. Retrospective review of our IRB-approved kidney cancer database examined a consecutive series of subjects from 1995 to 2012. We identified all mRCC patients with radiographic evidence of renal cell brain metastasis (RCCBM). RCCBM patients were divided into two cohorts: CNS symptoms present at RCCBM diagnosis and those without symptoms present at diagnosis. Fifty-two patients within our database met criteria; CNS symptoms were present at RCCBM diagnosis in 73 % (36) of patients. Median size of RCCBM on presentation was smaller in the asymptomatic verses the symptomatic cohort (0.83 vs. 1.7 cm, p = 0.003). Multivariate analysis demonstrated presence of CNS symptoms and female gender as a survival advantage (p < 0.05) while poor performance status, history of tobacco abuse and coexistence of lung metastasis were poor indicators for survival (p < 0.05). Patients with pulmonary metastases and a history of tobacco abuse are more likely to harbor RCCBM and perhaps in the absence of CNS symptoms these subjects should have routine brain surveillance incorporated into the RCC follow up. Overall, the current urologic guidelines may be missing a subset of metastatic RCC patients who could potentially benefit from early radiation or neurosurgical intervention. This may result in improved overall survival.

Control of brain metastases from radioresistant tumors treated by stereotactic radiosurgery

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

Competing Risk Analysis of Neurologic versus Nonneurologic Death in Patients Undergoing Radiosurgical Salvage After Whole-Brain Radiation Therapy Failure: Who Actually Dies of Their Brain Metastases?

PURPOSE

To estimate the hazard for neurologic (central nervous system, CNS) and nonneurologic (non-CNS) death associated with patient, treatment, and systemic disease status in patients receiving stereotactic radiosurgery after whole-brain radiation therapy (WBRT) failure, using a competing risk model.

PATIENTS AND METHODS

Of 757 patients, 293 experienced recurrence or new metastasis following WBRT. Univariate Cox proportional hazards regression identified covariates for consideration in the multivariate model. Competing risks multivariable regression was performed to estimate the adjusted hazard ratio (aHR) and 95% confidence interval (CI) for both CNS and non-CNS death after adjusting for patient, disease, and treatment factors. The resultant model was converted into an online calculator for ease of clinical use.

RESULTS

The cumulative incidence of CNS and non-CNS death at 6 and 12 months was 20.6% and 21.6%, and 34.4% and 35%, respectively. Patients with melanoma histology (relative to breast) (aHR 2.7, 95% CI 1.5-5.0), brainstem location (aHR 2.1, 95% CI 1.3-3.5), and number of metastases (aHR 1.09, 95% CI 1.04-1.2) had increased aHR for CNS death. Progressive systemic disease (aHR 0.55, 95% CI 0.4-0.8) and increasing lowest margin dose (aHR 0.97, 95% CI 0.9-0.99) were protective against CNS death. Patients with lung histology (aHR 1.3, 95% CI 1.1-1.9) and progressive systemic disease (aHR 2.14, 95% CI 1.5-3.0) had increased aHR for non-CNS death.

CONCLUSION

Our nomogram provides individual estimates of neurologic death after salvage stereotactic radiosurgery for patients who have failed prior WBRT, based on histology, neuroanatomical location, age, lowest margin dose, and number of metastases after adjusting for their competing risk of death from other causes.