Treatment Of Brain Metastases Research Articles

Association between systemic treatment with immune checkpoint inhibitor therapy in renal cell carcinoma and reduced risk of brain metastasis development.

Immune checkpoint inhibitor (ICI) efficacy in the treatment of metastatic renal cell carcinoma (RCC) without brain metastases (BMs) is well established in several clinical trials; however, patients with BMs were typically excluded from these trials. Therefore, the efficacy of ICI in the treatment or prevention of BM remains unclear. The primary aim of the study was to address the efficacy of ICI in treatment of patients with RCC BMs compared with patients receiving targeted therapies. A secondary aim was to evaluate the risk of RCC BM development among patients who received ICI versus targeted therapies early in their treatment course. A retrospective single-center review between 2011 and 2018 identified 425 patients treated for metastatic RCC. The study group included patients who received ICI and/or targeted therapies during their disease. Data analyzed included demographic information, systemic treatments, overall survival from RCC diagnosis (OSRCC) and from BM diagnosis (OSBM), and BM development. Fisher's exact test was used to evaluate the frequency of BM occurrence. Survival was assessed using Kaplan-Meier curves and log-rank tests. Of the 425 patients, 125 received ICI and 300 were treated with molecular targeted agents only during their clinical course. BMs occurred in 113 (9.5%) of the 425 patients. Among patients with BMs, OSRCC was improved with the use of ICI (77.2 vs 25.2 months, p < 0.001), with 1-, 2-, and 5-year survival rates of 93.9%, 81.8%, and 62.6%, respectively. The use of ICI was associated with increased OSBM (21.7 vs 8.9 months, p = 0.001). The rate of BM development was lower when patients were treated with ICI (8/100 [8.0%]) compared with targeted therapy (47/267 [17.6%]) (OR 0.41, 95% CI 0.18-0.89; p = 0.021). ICI was associated with improved OSRCC and OSBM in patients with BMs and decreased the probability of BM development in patients with metastatic RCC. Prospective trials are needed to further evaluate optimal use of ICI in treatment of RCC BMs.

Prognosis of breast cancer patients with brain metastasis treated with radiotherapy

Background Life expectancy for patients diagnosed with metastatic breast cancer (BC) has improved in recent years, especially due to better systemic treatment. This has led to an increased incidence of brain metastases (BM), and BC is now the leading cause of BM in women. Treatment of BM primarily consists of surgery and/or radiotherapy. We aimed to investigate survival time and prognostic factors for BC patients treated with radiotherapy for BM. Material & methods During the period 1st of January 2015 to 1st of June 2020, 144 consecutive BC patients treated for BM from one centre were retrospectively analyzed. The patients were either diagnosed with BM as the first metastatic lesion, or developed BM during palliative therapy for distant non-brain metastasis. The study was approved by the Central Denmark Region. Results Median age at BM diagnosis was 66 years, and 90% of the patients already had extracranial metastatic disease at BM diagnosis. Median overall survival after diagnosis of BM was 6.1 months. Short survival was observed for patients with poor performance status, leptomeningeal metastasis or more than three solid BM. Several of these factors were overrepresented in patients with estrogen receptor-positive (ER+) tumours who had poorer survival than patients with different receptor status. Conclusion The number of metastatic BC patients developing BM is high, and survival following local treatment remains poor. Several prognostic factors appear to influence survival after radiotherapy. Treatment of BC patients with BM should be individualized according to performance status, leptomeningeal disease, number of BM, and receptor status of the disease.

Navigating the Blood-Brain Barrier: Challenges and Therapeutic Strategies in Breast Cancer Brain Metastases.

Breast cancer (BC) is the most common cancer in women, with metastatic BC being responsible for the highest number of deaths. A frequent site for BC metastasis is the brain. Brain metastasis derived from BC involves the cooperation of multiple genetic, epigenetic, angiogenic, and tumor-stroma interactions. Most of these interactions provide a unique opportunity for development of new therapeutic targets. Potentially targetable signaling pathways are Notch, Wnt, and the epidermal growth factor receptors signaling pathways, all of which are linked to driving BC brain metastasis (BCBM). However, a major challenge in treating brain metastasis remains the blood-brain barrier (BBB). This barrier restricts the access of unwanted molecules, cells, and targeted therapies to the brain parenchyma. Moreover, current therapies to treat brain metastases, such as stereotactic radiosurgery and whole-brain radiotherapy, have limited efficacy. Promising new drugs like phosphatase and kinase modulators, as well as BBB disruptors and immunotherapeutic strategies, have shown the potential to ease the disease in preclinical studies, but remain limited by multiple resistance mechanisms. This review summarizes some of the current understanding of the mechanisms involved in BC brain metastasis and highlights current challenges as well as opportunities in strategic designs of potentially successful future therapies.

Circulating hsa_circ_0072309, acting via the miR-100/ACKR3 pathway, maybe a potential biomarker for the diagnosis, prognosis, and treatment of brain metastasis from non-small-cell lung cancer.

One of the main causes of lung cancer-related death is brain metastasis (BM). Finding early indicators of BM derived from lung cancer is crucial. Therefore, this study was designed to determine if serum hsa_circ_0072309 may be employed as a potential biomarker for BM induced by non-small-cell lung cancer (NSCLC) and to understand its possible underlying mechanism. Primary lung cancer and healthy neighboring tissues were obtained from all patients, while BM tissues were taken from BM+ patients. Serum specimens were collected from all patients and healthy volunteers. Hsa_circ_001653, miR-100, and ACKR3 RNA expressions were analyzed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and atypical chemokine receptor 3 (ACKR3) protein expression by western blotting (WB), immunohistochemistry (IHC), and enzyme-linked immunosorbent assay (ELISA). In order to examine the effect of serum hsa_circ_0072309 and its relevant mechanism on BM development, an NSCLC-associated BM model in mice was established. According to the results, miR-100 expression was down-regulated in primary lung cancer tissues compared to healthy lung tissues in all NSCLC patients, and circ_0072309 and ACKR3 expression were up-regulated. In BM tissues compared with primary lung tumors of BM+ patients, in serum samples from all patients compared to healthy volunteers, and in lung tumors of BM+ patients compared to those from BM- patients. Patients' serum exhibits the same level of hsa_circ_0072309/miR-100/ACKR3 expression as in BM samples. Advanced tumor-node-metastasis (TNM) stage, higher BM, shorter post-operative overall survival (OS), and progression-free survival (PFS) are all substantially associated with increased serum circ_0072309 levels in BM+ patients. In animal models, serum owning hsa_circ_0072309 from BM+ patients facilitates BM formation by regulating the miR-100/ACKR3 pathway. The current preliminary research reveals serum hsa_circ_0072309 as a possible biomarker and target for early diagnosis, prognosis, and therapy of NSCLC-derived BM and suggests a substantial role for the hsa_circ_0072309/miR-100/ACKR3 axis in the formation of BM from NSCLC.

Use of 18F-PSMA PET to Distinguish Cerebral Radiation Necrosis From Tumor Recurrence.

Brain metastasis in prostate adenocarcinoma is extremely rare and usually arises in the setting of widespread osseous and visceral metastases. Surgical resection and radiation therapy, including stereotactic radiosurgery, are the mainstays of treatment for brain metastasis. Radiation necrosis is a common complication of radiotherapy for brain metastasis, and distinguishing it from tumor recurrence by MRI is difficult because of overlapping findings. We present a 73-year-old man with prostate cancer with a solitary brain metastasis where PET with 18F-piflufolostat helped detect disease recurrence in the setting of ambiguous MRI findings.

Immune checkpoint inhibitor treatment of brain metastasis associated with a less invasive growth pattern, higher T-cell infiltration and raised tumor ADC on diffusion weighted MRI

BackgroundBrain metastases are the most common intracranial tumors with an increasing incidence. They are an important cause of morbidity and mortality in patients with solid organ cancer and a focus of recent clinical research and experimental interest. Immune checkpoint inhibitors are being increasingly used to treat solid organ cancers.MethodsTo determine whether immune checkpoint inhibitors were biologically effective in the brain, we compared melanoma brain metastasis samples where treatment with ipilimumab had occurred preoperatively to those who had not received any immune modulating therapy and looked for histopathological (invasion, vascularity, metastasis inducing proteins, matrix metalloproteinases, immune cell infiltration, tissue architecture) and advanced MRI differences (diffusion weighted imaging).ResultsCo-localized tissue samples from the same regions as MRI regions of interest showed significantly lower vascularity (density of CD34 + vessels) in the core and higher T-cell infiltration (CD3 + cells) in the leading edge for ipilimumab-treated brain metastasis samples than for untreated cases and this correlated with a higher tumor ADC signal at post-treatment/preoperative MRI brain.ConclusionsTreatment of a melanoma brain metastasis with ipilimumab appears to cause measurable biological changes in the tumor that can be correlated with post-treatment diffusion weighted MRI imaging, suggesting both a mechanism of action and a possible surrogate marker of efficacy.

Outcome assessment of intraoperative radiotherapy for brain metastases: results of a prospective observational study with comparative matched-pair analysis

PurposeIntraoperative radiation therapy (IORT) is an emerging alternative to adjuvant stereotactic external beam radiation therapy (EBRT) following resection of brain metastases (BM). Advantages of IORT include an instant prevention of tumor regrowth, optimized dose-sparing of adjacent healthy brain tissue and immediate completion of BM treatment, allowing an earlier admission to subsequent systemic treatments. However, prospective outcome data are limited. We sought to assess long-term outcome of IORT in comparison to EBRT.MethodsA total of 35 consecutive patients, prospectively recruited within a study registry, who received IORT following BM resection at a single neuro-oncological center were evaluated for radiation necrosis (RN) incidence rates, local control rates (LCR), distant brain progression (DBP) and overall survival (OS) as long-term outcome parameters. The 1 year-estimated OS and survival rates were compared in a balanced comparative matched-pair analysis to those of our institutional database, encompassing 388 consecutive patients who underwent adjuvant EBRT after BM resection.ResultsThe median IORT dose was 30 Gy prescribed to the applicator surface. A 2.9% RN rate was observed. The estimated 1 year-LCR was 97.1% and the 1 year-DBP-free survival 73.5%. Median time to DBP was 6.4 (range 1.7–24) months in the subgroup of patients experiencing intracerebral progression. The median OS was 17.5 (0.5-not reached) months with a 1 year-survival rate of 61.3%, which did not not significantly differ from the comparative cohort (p = 0.55 and p = 0.82, respectively).ConclusionIORT is a safe and effective fast-track approach following BM resection, with comparable long-term outcomes as adjuvant EBRT.

Stereotactic radiotherapy for brain metastases: predictive factors of radionecrosis

PurposeStereotactic radiotherapy (SRT) is a highly effective approach and represents the current standard of treatment for patients with limited number of brain metastasis (BM). SRT is generally well tolerated but can sometimes lead to radionecrosis (RN). The aim of this study was to identify predictive factors of radionecrosis related to SRT for brain metastasis.MethodsThis retrospective observational cohort study included patients who underwent SRT in the Institut Sainte Catherine between January 1st, 2017 and December 31st, 2020 for the treatment of brain metastasis from any cancer. Individual data and particularly signs of radionecrosis (clinical, imaging, anatomopathological) were collected from electronic medical records. Radionecrosis was defined as the occurrence on MRI of contrast-enhancing necrotic lesions, surrounded by edema, occurring at least 6 months after SRT and localized within fields of irradiation.Results123 patients were included; median age was 66 years. 17 patients (11.8%) developed radionecrosis after a median follow up of 418.5 days [63;1498]. Predictive factors of radionecrosis in multivariate analysis were age under 66 years with a sensitivity of 77% and a specificity of 56%. No other factor as the presence of comorbidities, the number of irradiated metastases, the PTV volume or the volume of irradiated healthy brain were predictive of radionecrosis.ConclusionAge at treatment initiation and tumor location seems to be correlated with radionecrosis in patients with brain metastasis treated with SRT. These elements could be useful to adapted radiation therapy.

Immune checkpoint inhibitors for the treatment of non-small cell lung cancer brain metastases.

Lung cancer has the highest risk of brain metastasis (BM) among all solid carcinomas. The emergence of BM has a significant impact on the selection of oncologic treatment for patients. Immune checkpoint inhibitors (ICIs) are the most promising treatment option for patients without druggable mutations and have been shown to improve survival in patients with non-small cell lung cancer (NSCLC) BM in clinical trials with good safety. Moreover, ICI has shown certain effects in NSCLC BM, and the overall intracranial efficacy is comparable to extracranial efficacy. However, a proportion of patients showed discordant responses in primary and metastatic lesions, suggesting that multiple mechanisms may exist underlying ICI activity in BM. According to studies pertaining to tumor immune microenvironments, ICIs may be capable of provoking immunity in situ. Meanwhile, systematic immune cells activated by ICIs can migrate into the central nervous system and exert antitumor effects. This review summarizes the present evidence for ICI treatment efficacy in NSCLC BM and proposes the possible mechanisms of ICI treatment for NSCLC BMs based on existing evidence.

PD-L1 Positron Emission Tomography Imaging in Patients With Non-Small Cell Lung Cancer: Preliminary Results of the ImmunoPET Phase 0 Study

ImmunoPET is a multicenter, single arm, phase 0-1 study of 89Zr-DFO-Sq-durvalumab (89Zr-durvalumab), a novel PET tracer, designed to interrogate the expression of PD-L1 in patients with NSCLC. Clinically relevant findings from phase 0 are presented here. Phase 0 was designed to investigate tracer biodistribution and safety in patients with metastatic NSCLC with PD-L1 expression >25%. After 60MBq/70kg 89Zr-durvalumab infusion, PET/CT images were acquired at days 0, 1, 3 or 5 ± 24h. Baseline FDG PET/CT was performed prior to PD-L1 PET imaging. All five patients recruited to phase 0 completed the full imaging protocol. The only reported adverse event was a transient asymptomatic increase in respiratory rate. At the time of PD-L1 imaging, two patients were in complete remission on FDG-PET after treatment with osimertinib and pembrolizumab; neither showed PD-L1 tracer uptake in previous tumor sites. All three patients with active tumor had received radiotherapy to some or all disease sites prior to PD-L1 imaging. With the exception of a single disease site, specific uptake of 89Zr-durvalumab uptake was seen in tumours, with increasing uptake in tumor seen up to Day 5 post-injection. Patient 1, who had multiple metastases, including brain and bone, showed more intense 89Zr-durvalumab uptake in recently irradiated bone lesions than un-irradiated lesions and uptake was also observed in treated brain metastases.. One patient, who experienced rapid growth of a single lung lesion that had acquired resistance to pembrolizumab, showed no significant 89Zr-durvalumab in that lesion, despite recent radiotherapy. In patient 5, 89Zr-durvalumab uptake was observed in the viable rim of a large, recently irradiated adrenal oligometastasis. 89Zr- durvalumab imaging was safe and detected known viable tumor at multiple sites. Recently irradiated tumours showed the highest uptake and in another, a single site of immunotherapy resistant disease showed minimal tracer uptake. PD-L1 imaging may have utility in patients with NSCLC treated with radiotherapy.

PRO: Do We Still Need Whole-Brain Irradiation for Brain Metastases?

(1) Background: In recent decades, the use of whole-brain radiation therapy (WBRT) in the treatment of brain metastases has significantly decreased, with clinicians fearing adverse neurocognitive events and data showing limited efficacy regarding local tumor control and overall survival. The present study thus aimed to reassess the role that WBRT holds in the treatment of brain metastases. (2) Methods: This review summarizes the available evidence from 1990 until today supporting the use of WBRT, as well as new developments in WBRT and their clinical implications. (3) Results: While one to four brain metastases should be exclusively treated with radiosurgery, WBRT does remain an option for patients with multiple metastases. In particular, hippocampus-avoidance WBRT, WBRT with dose escalation to the metastases, and their combination have shown promising results and offer valid alternatives to local stereotactic radiotherapy. Ongoing and published prospective trials on the efficacy and toxicity of these new methods are presented. (4) Conclusions: Unlike conventional WBRT, which has limited indications, modern WBRT techniques continue to have a significant role to play in the treatment of multiple brain metastases. In which situations radiosurgery or WBRT should be the first option should be investigated in further studies. Until then, the therapeutic decision must be made individually depending on the oncological context.

Spatiotemporal fractionation schemes for stereotactic radiosurgery of multiple brain metastases.

Stereotactic radiosurgery (SRS) is an established treatment for patients with brain metastases (BMs). However, damage to the healthy brain may limit the tumor dose for patients with multiple lesions. In this study, we investigate the potential of spatiotemporal fractionation schemes to reduce the biological dose received by the healthy brain in SRS of multiple BMs, and also demonstrate a novel concept of spatiotemporal fractionation for polymetastatic cancer patients that faces less hurdles for clinical implementation. Spatiotemporal fractionation (STF) schemes aim at partial hypofractionation in the metastases along with more uniform fractionation in the healthy brain. This is achieved by delivering distinct dose distributions in different fractions, which are designed based on their cumulative biologically effective dose ( ) such that each fraction contributes with high doses to complementary parts of the target volume, while similar dose baths are delivered to the normal tissue. For patients with multiple brain metastases, a novel constrained approach to spatiotemporal fractionation (cSTF) is proposed, which is more robust against setup and biological uncertainties. The approach aims at irradiating entire metastases with possibly different doses, but spatially similar dose distributions in every fraction, where the optimal dose contribution of every fraction to each metastasis is determined using a new planning objective to be added to the BED-based treatment plan optimization problem. The benefits of spatiotemporal fractionation schemes are evaluated for three patients, each with >25 BMs. For the same tumor BED10 and the same brain volume exposed to high doses in all plans, the mean brain BED2 can be reduced compared to uniformly fractionated plans by 9%-12% with the cSTF plans and by 13%-19% with the STF plans. In contrast to the STF plans, the cSTF plans avoid partial irradiation of the individual metastases and are less sensitive to misalignments of the fractional dose distributions when setup errors occur. Spatiotemporal fractionation schemes represent an approach to lower the biological dose to the healthy brain in SRS-based treatments of multiple BMs. Although cSTF cannot achieve the full BED reduction of STF, it improves on uniform fractionation and is more robust against both setup errors and biological uncertainties related to partial tumor irradiation.

A multicenter study of central nervous system (CNS) metastasis in EGFR-mutated advanced non–small-cell lung cancer in Thailand: CNS progression-free survival analysis.

e14002 Background: Central Nervous System (CNS) metastasis is common in patients with advanced stage non-small cell lung cancer (NSCLC), which impacts their survival and quality of life. Nearly Half of NSCLCs in Thailand are EGFR (Epidermal Growth Factor Receptor) mutated NSCLCs. The aim of this study was to define the prevalence of CNS metastasis in EGFR mutated advanced NSCLC in Thai patients and their survival during the year 2013-2019.Now we reported CNS progression free survival data in subgroup with evidence of CNS progression. Methods: We retrospectively conducted a multicenter study of EGFR mutated advanced NSCLC from 9 government hospitals in Thailand from January 2013 to December2019. Demographic data and cancer treatments were recorded with previous reports of overall survival data in all cohorts. Brain imaging was performed upon neurologic signs and symptoms. Treatment of CNS metastasis, CNS progression date and overall survival data were collected. The analysis of CNS progression free survival and overall survival was performed and the effect of Osimertinib was defined. Results: There were 254 patients with advanced EGFR mutated NSCLCs. The prevalence of CNS metastasis was 32.28% (82 patients). There were 25.6% (21) of patients with definite evidence of CNS progression by imaging or clinical. In this group, Brain metastasis at first diagnosis was 61.9% (13 patients). EGFR TKIs was given as first line 42.9% (9 patients), second line 33.3% (7 patients), third line 19% (4 patients). Whereas one patient did not received EGFR TKIs. Most of EGFR TKIs treatment was first generation for 95% (19 patients). Osimertinib was given in 23.8% (5) of patients as second line, third line and fourth line for 2, 1 and 2 patients, respectively. The onset of CNS metastasis before EGFR TKIs was 76.2% when compared to 4.8%, 19% during EGFR TKIs and after EGFR TKIs, respectively. Treatment of brain metastasis was whole brain radiation for 85.7% (18 patients), followed by surgery with whole brain radiation for 14.3% (3 patients). The median CNS progression free survival was 14.00 (9.51,18.48) months. The median CNS progression free survival between no Osimertinib treatment and Osimertinib treatment was 13 (10.38,15.61) months and 21 (17.49,24.5) months, respectively. The median survival was 30.03 (19.6,40.45) months. The median survival between no Osimertinib treatment and Osimertinib treatment was 26.58 (18.96,34.20) months and NR (NR, NR), respectively. Conclusions: The prevalence of CNS progression was 25.6% in patients with EGFR mutated NSCLC in Thailand. Treatment with EGFR TKIs improved CNS progression free survival better than historical data.3rd generation EGFR TKIs Osimertinib in later line prolong clinical benefit of CNS Progression free survival and overall survival better than 1st generation EGFR TKIs alone.

Stereotactic Radiosurgery as Treatment for Brain Metastases: An Update.

Stereotactic radiosurgery (SRS) is a mainstay treatment option for brain metastasis (BM). While guidelines for SRS use have been outlined by professional societies, consideration of these guidelines should be weighed in the context of emerging literature, novel technology platforms, and contemporary treatment paradigms. Here, we review recent advances in prognostic scale development for SRS-treated BM patients and survival outcomes as a function of the number of BM and cumulative intracranial tumor volume. Focus is placed on the role of stereotactic laser thermal ablation in the management of BM that recur after SRS and the management of radiation necrosis. Neoadjuvant SRS prior to surgical resection as a means of minimizing leptomeningeal spread is also discussed.

Phase I/II study of stereotactic radiosurgery with concurrent olaparib followed by adjuvant durvalumab and physician’s choice systemic therapy in patients with breast cancer brain metastases.

TPS1133 Background: Despite progress in the treatment of brain metastasis for HER2+ breast cancer, outcomes for patients with HER2-negative breast cancer brain metastases remain poor. Current standard of care consists of local therapies, including surgery and radiotherapy, followed by systemic therapy. Preclinical studies show inhibitors of poly(ADP-ribose) polymerase (PARP) are effective in combination with radiation therapy as a DNA damage response inhibitor. Triple-negative breast cancer (TNBC) has higher rates of homologous recombination deficiency compared to other breast cancer subtypes, and together with HER2-negative, BRCA-mutated breast cancer would be particularly sensitive to PARP inhibition. PARP inhibition has also demonstrated promising efficacy combined with immunotherapy in patients with germline BRCA-mutant and metastatic TNBC in clinical trials (MEDIOLA, TOPACIO). In addition, immunotherapy with stereotactic radiosurgery (SRS) is associated with favorable intracranial control and survival in patients with brain metastases. We hypothesize that this biologically-driven combination will enhance local control of SRS-treated brain metastases through synergy with PARP inhibition, while controlling micrometastatic disease in the brain and extracranial sites via potentiation of the immune response. Methods: We are conducting a multi-institution, Phase I/II trial of SRS plus olaparib, followed by durvalumab (with physician’s choice systemic therapy), for patients with TNBC (any BRCA status) or HER2-negative with BRCA-mutated (germline or somatic) breast cancer brain metastases [NCT04711824]. A total of 41 patients are planned for enrollment at 8 sites. The primary objectives are to evaluate safety and tolerability (Phase I) and determine intracranial disease control at 6 months (Phase II) of this treatment combination. Secondary objectives include determining clinical activity via intracranial and global progression-free survival, overall survival, and intracranial and extracranial response rate. Exploratory objectives will assess potential biomarkers of treatment response, including changes in circulating tumor cells and DNA in blood and cerebrospinal fluid, germline and tumor mutations in DNA repair pathway genes, and PD-L1 expression, as well as quality of life and patient-reported outcomes. A surgical sub-study (n=5) will evaluate olaparib concentration/distribution in resected brain metastases. As of January 2023, cohort 1 of phase I has been completed without dose-limiting toxicity. Clinical trial information: NCT04711824 .

Safety and efficacy of silibinin in patients with brain metastases after stereotactc radiosurgery: SUSTAIN trial.

e14012 Background: Brain metastases (BMs) account for more than one-half of all intracranial tumors. Over the past years, stereotactic radiosurgery (SRS) has become the mainstay of BMs treatment, providing high rates of local tumor control. Nevertheless, SRS alone is associated with a 30-50% risk of distant brain failure (DBF), consequently requiring careful follow-up and possible rescue treatments. Silibinin or silybin, a natural polyphenolic flavonoid, has shown promising antitumor activity, leading to improvement of BMs in patients (pts) with progressive non-small cell lung cancer. Therefore, our exploratory study aims to evaluate whether the use of a silibinin-based nutraceutical can significantly reduce DBF rate at 6 months in pts with first-diagnosed BMs treated with SRS with or without surgery. Methods: SUSTAIN is an interventional, prospective, single arm, phase II study. A total of 80 pts treated in our center are planned to be enrolled. Pts receive 2 capsules (cps) of silibinin-based nutraceutical per day for the first month after SRS and 1 cp per day thereafter. Primary endpoints are 6-month distant brain failure (DBF) rate and safety; secondary endpoint is 6-month overall survival (OS) rate. Contrast-enhanced magnetic resonance (MRI) of the brain is performed at baseline and every 12 weeks after SRS treatment; radiological response is assessed according to RANO criteria for brain metastases (RANO-BM). Results: Thirty pts has been enrolled at the time of this primary analysis (Tab1). NSCLC and breast cancer were the prevalent histologies (14 and 10 cases respectively). Twelve pts were chemotherapy naive at the time of BMs diagnosis; 10 pts has received 1 systemic therapy line and 8 pts has received 2 lines or more. Overall, the number of treated lesions was 73, with a median of 1 lesion (range 1-9). All pts underwent SRS (Fig.1), with a median prescription dose (PD) and a median prescription isodose line (IDL) of 24 Gy and 80% respectively. After a 14-month enrollment period, with a median follow-up of 9 months, 6 pts reported distant intracranial failure according to RANO-BM criteria, with a 6-month DBF rate of 20%. Only 1 treated lesion met the criteria for progression, accounting for a 6-month local control (LC) rate of 98%. Six pts died, with a 6-month OS rate of 80%. Radiological radionecrosis was detected in 3 pts (10%), who developed G1 neurological symptoms managed with low-dose dexamethasone. Two pts discontinued silibinin-based nutraceutical assumption due to G1 nausea. No other adverse events were reported. Conclusions: At about half of our enrollment target, the results show a favorable trend towards 6-month DBF rate reduction. Toxicity proved manageable, consistent with the literature and limited to gastrointestinal effects. A larger sample and longer follow-up is needed to confirm our hypothesis.

A Survival Tree of Advanced Melanoma Patients with Brain Metastases Treated with Immune Checkpoint Inhibitors.

The efficacy of immune checkpoint inhibitors (ICIs) in patients with advanced melanoma that develop brain metastases (BM) remains unpredictable. In this study, we aimed to identify prognostic factors in patients with melanoma BM who are treated with ICIs. Data from advanced melanoma patients with BM treated with ICIs in any line between 2013 and 2020 were obtained from the Dutch Melanoma Treatment Registry. Patients were included from the time of the treatment of BM with ICIs. Survival tree analysis was performed with clinicopathological parameters as potential classifiers and overall survival (OS) as the response variable. In total, 1278 patients were included. Most patients were treated with ipilimumab-nivolumab combination therapy (45%). The survival tree analysis resulted in 31 subgroups. The median OS ranged from 2.7 months to 35.7 months. The strongest clinical parameter associated with survival in advanced melanoma patients with BM was the serum lactate dehydrogenase (LDH) level. Patients with elevated LDH levels and symptomatic BM had the worst prognosis. The clinicopathological classifiers identified in this study can contribute to optimizing clinical studies and can aid doctors in giving an indication of the patients' survival based on their baseline and disease characteristics.

Prognostic factors associated with the transition in treatment methods for brain metastases from colorectal cancer.

Treatment of brain metastases (BMs) from colorectal cancer (CRC) has transitioned with the expansion of indications for stereotactic radiotherapy. Our study aimed to assess changes in prognosis and prognostic factors associated with changes in treatment for BMs from CRC. We retrospectively surveyed treatments for and outcomes of BMs from CRC in 208 patients treated during 1997-2018. Patients were divided into two groups according to time of BM diagnosis, i.e., 1997-2013 ("first period") and 2014-2018 ("second period"). We compared overall survival between the periods and assessed how the transition impacted prognostic factors affecting overall survival, including the following prognostic factors such as Karnofsky performance status (KPS), volume-related factors (BM number and diameter), and BM treatment modalities as covariates. Of the 208 patients, 147 were treated in the first period and 61 in the second period. Whole-brain radiotherapy use decreased from 67 to 39% in the second period, and stereotactic radiotherapy use increased from 30 to 62%. Median survival after BM diagnosis improved from 6.1 to 8.5months (p = 0.0272). Multivariate analysis revealed KPS, control of primary tumor, stereotactic radiotherapy use, and chemotherapy history as independent prognostic factors during the entire observation period. Hazard ratios of KPS, primary tumor control, and stereotactic radiotherapy were higher in the second period, whereas prognostic impact of chemotherapy history before BM diagnosis was similar in both periods. Overall survival of patients with BMs from CRC improved since 2014, which can be attributed to advances in chemotherapy and the more widespread use of stereotactic radiotherapy.

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.

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). 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. 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. 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.

Evaluation of Dosimetry Metrics in Single Isocenter Multiple Targets and Single Isocenter Single Target in the Treatment of Brain Metastases

Purpose: This study compares two LINAC-based techniques for treating multiple brain lesions using quantitative evaluation of plan dosimetric indices. Material and Methods: Twenty-one patients with a total of 168 targets were selected. All plans were designed with five non-coplanar arcs in the RayStation treatment planning system (TPS). The composite dose of Multiple Isocenter Multiple Targets (MIMT) was compared to that of single isocenter multiple targets (SIMT) by evaluating conformity indices, Paddick gradient-index (PGI), V8, V12, and Delivery Time (DT).