Brain Metastasis-free Survival Research Articles

Comprehensive analysis of stereotactic Radiosurgery outcomes in triple-negative breast cancer patients with brain metastases: The influence of immunotherapy and prognostic factors

IntroductionBreast cancer stands as the second most common solid tumors with a propensity for brain metastasis. Among metastatic breast cancer cases, the brain metastasis incidence ranges from 10 % to 30 %, with triple-negative breast cancer (TNBC) displaying a heightened risk and poorer prognosis. SRS has emerged as an effective local treatment modality for brain metastases; however, data on its outcomes specifically in pure triple-negative subtype remain scarce. MethodWe retrospectively reviewed the electronic medical records of all brain metastasis (BM) TNBC patients treated with SRS. Patient, tumour characteristics and treatment details data were collected. This retrospective cohort study aimed to evaluate local control (LC), distant brain metastasis free survival (DBMFS), and overall survival (OS) outcomes in TNBC patients undergoing SRS for brain metastases while identifying potential prognostic factors. ResultForty-three patients with TNBC and brain metastases treated with SRS between January 2017 and 2023 were included. The study found rates of LC (99 % at 1 year) and DBMFS (76 % at 1 year) after SRS, with brain metastasis count (p = 0,003) and systemic treatment modality (p = 0,001) being significant predictors of DBMFS. The median OS following SRS was 19.5 months, with neurological deficit (p = 0.003) and systemic treatment modality (p = 0.019) identified as significant predictors of OS. ConclusionSRS demonstrates favourable outcomes in terms of local control and distant brain metastasis-free survival in TNBC. Neurological deficit and systemic treatment significantly influence overall survival, emphasizing the importance of personalized treatment approaches and (magnetic resonance imaging) MRI surveillance based on these factors.

Dual-agent immunotherapy for prevention of melanoma brain metastases: A real-world analysis of 8686 patients.

2022 Background: Melanoma brain metastases (MBM) are a common endpoint among patients with advanced melanoma and prognosis is poor. Strategies for MBM prevention can prolong life and reduce morbidity. Dual agent immunotherapy (dIT) has been paradigm-changing in management malignant melanoma management. Recent clinical trials have supported the role of dIT for upfront management of small, asymptomatic MBM. Yet, its potential role in extending brain metastasis-free survival (BMFS) and decreasing MBM incidence overall has not been explored. The objective was to compare MBM incidence, median overall survival (OS), and BMFS in melanoma patients treated with dIT versus single immunotherapy (sIT). Methods: A real-world deidentified database collating clinical information from 92 organizations (TriNetX, Inc.) was queried. Melanoma patients without brain metastases prior to immunotherapy were stratified by treatment (anti-CTLA4 [sIT] and combination anti-CTLA4/ anti-PD1 [dIT]) and propensity-score matched. MBM incidence was measured within 5 years post-IT initiation. A complementary single-institution retrospective cohort study analyzed melanoma patients treated from 2012-2019. Median OS and BMFS were compared via log-rank tests and multivariate Cox proportional-hazards models. A competing risk analysis was performed to measure the cumulative incidences of MBM and death without MBM. Results: TriNetX identified 8,686 melanoma patients who received immunotherapy (4,585 dIT; 4,101 sIT). MBM incidence was 13.4%, and 19.3%, for the dIT and sIT cohorts, respectively (p < 0.0001). DIT was associated with a lower likelihood of developing MBM compared to sIT (RR [95%CI], 0.69 [0.62-0.77]). After propensity-score matching on demographics and comorbidities, MBM incidence was similarly 13.3% and 18.5% for the dIT and sIT cohorts, respectively. On single-institution analysis, 130 melanoma patients were included (87 dIT; 43 sIT with anti-CTLA4). In patients with stage IV disease, median OS was 1.70 and 3.66 years for the sIT and dIT cohorts, respectively (p=0.6). Median BMFS was 1.56 and 2.36 years in the sIT and dIT cohorts respectively (p=0.76). On multivariable Cox proportional hazard regression analysis, NRAS mutation was significantly correlated with a worse prognosis for BMFS. Conclusions: These data highlight the impact of combination anti-CTL4/ anti-PD1 immunotherapy in decreasing MBM incidence. The potential primary prophylactic role of dIT in MBM warrants prospective exploration, including mechanistic understanding.

The development of brain metastases in patients with different therapeutic strategies for metastatic renal cell cancer.

A diagnosis of brain metastasis (BM) significantly affects quality of life in patients with metastatic renal cell cancer (mRCC). Although systemic treatments have shown efficacy in mRCC, active surveillance (AS) is still commonly used in clinical practice. In this single-center cohort study, we assessed the impact of different initial treatment strategies for metastatic RCC (mRCC) on the development of BM. All consecutive patients diagnosed with mRCC between 2011 and 2022 were included at the Erasmus MC Cancer Institute, the Netherlands, and a subgroup of patients with BM was selected. In total, 381 patients with mRCC (ECM, BM, or both) were identified. Forty-six patients had BM of whom 39 had metachronous BM (diagnosed ≥1 month after ECM). Twenty-five (64.1%) of these 39 patients with metachronous BM had received prior systemic treatment for ECM and 14 (35.9%) patients were treatment naive at BM diagnosis. The median BM-free survival since ECM diagnosis was significantly longer (p = .02) in previously treated patients (29.0 [IQR 12.6-57.0] months) compared to treatment naive patients (6.8 [IQR 1.0-7.0] months). In conclusion, patients with mRCC who received systemic treatment for ECM prior to BM diagnosis had a longer BM-free survival as compared to treatment naïve patients. These results emphasize the need for careful evaluation of treatment strategies, and especially AS, for patients with mRCC.

Abstract PO3-18-11: A011801 (CompassHER2 RD): Postneoadjuvant T-DM1 + tucatinib/placebo in patients with residual HER2-positive invasive breast cancer

Abstract Background: Patients with HER2+ early breast cancer (EBC) and invasive residual disease (RD) after neoadjuvant therapy (NAT) have a higher risk of relapse than patients who have a pathologic complete response (pCR). Escalation of therapy in patients with RD using post-neoadjuvant T-DM1 has become the new standard of care, leading to improved invasive disease-free survival (iDFS), but patients with estrogen receptor (ER)-negative or nodal RD have suboptimal outcomes, and central nervous system recurrences are a challenge. More effective treatment strategies are urgently needed. Alliance A011801 (CompassHER2 RD) is an escalation trial for patients with high-risk HER2+ RD after neoadjuvant systemic therapy, evaluating the addition of the HER2 selective tyrosine kinase inhibitor (TKI) tucatinib to post-neoadjuvant T-DM1. Methods: Eligibility and Intervention: Patients with high-risk HER2+ RD (i.e., ER-, node-positive, or both) after a predefined course of neoadjuvant HER2-directed treatment are randomized 1:1 to adjuvant T-DM1 + placebo, vs. T-DM1 and tucatinib with adjuvant RT +/- ET. Eligibility criteria include completion of ≥ 6 cycles of NAT, including ≥ 9 weeks of paclitaxel and trastuzumab +/- pertuzumab. All chemotherapy (CT) must be completed preoperatively unless participating in EA1181 (~15-30% will be participants in the CompassHER2 pCR de-escalation companion trial [NCT04266249]; these patients must receive postoperative CT to complete ≥ 6 cycles prior to enrollment on A011801). Patients who received prior HER2-targeted TKIs or antibody-drug conjugates are ineligible. Objectives: The primary objective is to determine if iDFS is improved with addition of tucatinib to T-DM1 in patients with HER2+ EBC with RD after neoadjuvant systemic therapy; secondary endpoints include overall survival, breast cancer free survival, distant recurrence-free survival, brain metastases-free survival and disease-free survival. Correlative objectives include the association of i) tumor infiltrating lymphocyte (TILs) levels in the primary tumor and RD with iDFS, ii) TILs with tucatinib benefit, iii) iDFS and circulating tumor cells (CTC) at serial timepoints and iv) the magnitude of benefit of tucatinib (iDFS) in patients with/without detectable pretreatment CTCs. Quality of life and pharmacokinetic endpoints are also being evaluated. Statistics: A011801 is a prospective, double-blind, randomized, phase III superiority trial; stratified by i) receipt of postoperative CT (Y/N), ii) hormone receptor-status (+/-), and iii) pathologic lymph node status (+/-). The study targets an absolute difference of 5% in iDFS (control vs. experimental arm 82% & 87%, HR = 0.7), with a two-sided alpha of 0.05 and power of 80%. The sample size is 981; target accrual = 1031 patients; activation and estimated completion dates are 01/6/21 and ~ 01/2028. Accrual as of 7/10/2023: 438 patients. Support: U10CA180821, U10CA180882; Seagen Inc; https://acknowledgments.alliancefound.org. ClinicalTrials.gov Identifier: NCT04457596 Citation Format: Ciara O'Sullivan, Karla Ballman, Linda McCall, Tyler Zemla, Anna Weiss, Melissa Mitchell, Victoria Blinder, Nadine Tung, William Irvin, Myounghee Lee, Sailaja Kamaraju, Matthew Goetz, W. Fraser Symmans, Virginia Borges, Ian Krop, Ann Partridge, Lisa Carey. A011801 (CompassHER2 RD): Postneoadjuvant T-DM1 + tucatinib/placebo in patients with residual HER2-positive invasive breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-18-11.

Rational and design of prophylactic cranial irradiation (PCI) and brain MRI surveillance versus brain MRI surveillance alone in patients with limited-stage small cell lung cancer achieving complete remission (CR) of tumor after chemoradiotherapy: a multicenter prospective randomized study

BackgroundProphylactic cranial irradiation (PCI) is part of standard care in limited-stage small cell lung cancer (SCLC) at present. As evidence from retrospective studies increases, the benefits of PCI for limited-stage SCLC are being challenged.MethodsA multicenter, prospective, randomized controlled study was designed. The key inclusion criteria were: histologically or cytologically confirmed small cell carcinoma, age ≥ 18 years, KPS ≥ 80, limited-stage is defined as tumor confined to one side of the chest including ipsilateral hilar, bilateral mediastinum and supraclavicular lymph nodes, patients have received definitive thoracic radiotherapy (regardless of the dose-fractionation of radiotherapy used) and chemotherapy, evaluated as complete remission (CR) of tumor 4–6 weeks after the completion of chemo-radiotherapy. Eligible patients will be randomly assigned to two arms: (1) PCI and brain MRI surveillance arm, receiving PCI (2.5 Gy qd to a total dose of 25 Gy in two weeks) followed by brain MRI surveillance once every three months for two years; (2) brain MRI surveillance alone arm, undergoing brain MRI surveillance once every three months for two years. The primary objective is to compare the 2-year brain metastasis-free survival (BMFS) rates between the two arms. Secondary objectives include 2-year overall survival (OS) rates, intra-cranial failure patterns, 2-year progression-free survival rates and neurotoxicity. In case of brain metastasis (BM) detect during follow-up, stereotactic radiosurgery (SRS) will be recommended if patients meet the eligibility criteria.DiscussionBased on our post-hoc analysis of a prospective study, we hypothesize that in limited-stage SCLC patients with CR after definitive chemoradiotherapy, and ruling out of BM by MRI, it would be feasible to use brain MRI surveillance and omit PCI in these patients. If BM is detected during follow-up, treatment with SRS or whole brain radiotherapy does not appear to have a detrimental effect on OS. Additionally, this approach may reduce potential neurotoxicity associated with PCI.

Abstract 3782: IASLC grading system predict distant metastases for resected lung adenocarcinoma

Abstract The International Association for the Study of Lung Cancer (IASLC) proposed a new histological grading system for invasive lung adenocarcinoma (LUAD). However, whether this new grading system is able to predict distant metastases in LUAD patients has not been evaluated. This study investigated the feasibility of using this grading system to predict the occurrence of brain and bone metastases in patients with resectable LUAD which identifies patients who have a high probability of developing distant metastases after surgery. We collected clinical information and pathological reports of 179 early stage LUAD patients who underwent resection during 2008 to 2015 from Wake Forest Comprehensive Cancer Center. All patients were followed up for 5 years and both bone and brain metastasis-free survival were calculated. Tumor grading of all samples was evaluated by both IASLC grading and predominant pattern-based grading systems. The ability of predicting distant metastases using IASLC grading and tumor stage were examined by receiver operating characteristic curves (ROC). 28 out of 179 patients developed distant metastases in five years with a median overall survival of 60 months for metastasis-free patients and 38.9 for patients with distant metastasis. Compared to predominant pattern-based grading system, IASLC grading system showed a stronger correlation with distant metastasis incidence. Complex gland pattern is enriched in patients who developed bone and brain metastases compared to metastasis-free patients. IASLC grading system also showed a superior prediction power of distant metastasis compared to tumor stage with area under curve (AUC) of 0.69 for brain metastasis and 0.71 for bone metastasis. IASLC grading system is capable of predicting the incidence of distant metastasis among early-stage invasive LUAD patients. Citation Format: Yuezhu Wang, Margaret R. Smith, Yin Liu, Mary E. Green, Omer A. Hassan, Alexandra M. Balmaceda, Tammy Sexton, Wencheng Li, Fei Xing. IASLC grading system predict distant metastases for resected lung adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3782.

Comprehensive genomic and clinical analyses identify APOBEC mutational signatures as a brain metastasis risk factor in lung adenocarcinoma patients

BackgroundLung adenocarcinoma is the most common source of brain metastasis (BM), resulting in significant morbidity and mortality. We aimed to identify patients with high BM risk who possibly benefit from brain-penetrant drugs, prophylactic cranial irradiation, or close brain magnetic resonance imaging surveillance. MethodsMetastatic lung adenocarcinoma patients with extracranial tumor samples profiled by a next-generation sequencing panel targeting 425 tumor-related genes were retrospectively enrolled between February 2008 and July 2021. We compared BM and non-BM patients’ genomic and clinical features and studied their associations with BM risk. Two external cohorts were used for result validation and molecular mechanisms investigation, respectively. ResultsWe included 174 eligible patients, including 90 having developed BM by the end of follow-up. Age≤60, EGFR activating mutations, and high-level apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like (APOBEC) mutational signatures were associated with elevated BM risk. Similar findings in BM-free survival were obtained by fitting Fine-Gray subdistribution hazard models addressing competing risks. Increased BM risk related to APOBEC mutational signatures was validated in an external cohort (N = 440). RNA sequencing data analyses performed in another external cohort (N = 230) revealed that expressions of metastasis-related pathways such as transforming growth factor (TGF)β and epithelial-mesenchymal transition (EMT) were upregulated in the patients with high-level APOBEC mutational signatures. ConclusionAPOBEC mutational signatures related to upregulated TGFβ and EMT, could serve as an independent risk factor for BM and BM-free survival in metastatic lung adenocarcinoma patients. Further investigations are warranted to tailor personalized treatments to improve the susceptible patient's outcomes.

Pathological Complete Response as Outcome Modifier in Breast Cancer Patients and Brain Metastasis.

Breast cancer with brain metastases (BCBM) has dreadful outcomes. Various factors influencing outcomes are age, receptors status, number of distant metastases, performance status, leptomeningeal metastasis, chemotherapies, and whole brain radiation dose. This study aimed to find outcome-modifying factors in BCBM. Clinical, demographic, subtype, and pathological response of primary brain imaging characteristics of BCBM patients were correlated with brain metastasis-free interval and survival after brain metastasis was studied from January 2020 to March 2022. Triple-negative breast cancer (TNBC) patients had the earliest presentation for brain metastases (mean 45.4years) vs luminal B (mean 57.93years). Both brain metastasis-free interval (BMFI) and brain metastasis overall survival (BMOS) were maximum in HER2-positive subtype (mean 22.8 and 11.55months) and least in TNBC patients (mean 9.8 and 2.12months), respectively. Low-graded prognosis assessment (GPA) score and leptomeningeal metastasis were associated with the worst outcomes. BMFI and BMOS in patients with pathological complete response (PCR) were at 28.5 and 15.1months, in partial response were 18.5 and 7.66months, and with stable or progressive disease were 11 and 1.36months, respectively. In the present study, PCR was the only modifiable parameter that changed breast cancer outcomes with brain metastasis and leptomeningeal metastasis was associated with the worst outcomes. Our study favors that PCR has prognostic importance.

Enhancing brain metastasis prediction in non-small cell lung cancer: a deep learning-based segmentation and CT radiomics-based ensemble learning model

BackgroundBrain metastasis (BM) is most common in non-small cell lung cancer (NSCLC) patients. This study aims to enhance BM risk prediction within three years for advanced NSCLC patients by using a deep learning-based segmentation and computed tomography (CT) radiomics-based ensemble learning model.MethodsThis retrospective study included 602 stage IIIA-IVB NSCLC patients, 309 BM patients and 293 non-BM patients, from two centers. Patients were divided into a training cohort (N = 376), an internal validation cohort (N = 161) and an external validation cohort (N = 65). Lung tumors were first segmented by using a three-dimensional (3D) deep residual U-Net network. Then, a total of 1106 radiomics features were computed by using pretreatment lung CT images to decode the imaging phenotypes of primary lung cancer. To reduce the dimensionality of the radiomics features, recursive feature elimination configured with the least absolute shrinkage and selection operator (LASSO) regularization method was applied to select the optimal image features after removing the low-variance features. An ensemble learning algorithm of the extreme gradient boosting (XGBoost) classifier was used to train and build a prediction model by fusing radiomics features and clinical features. Finally, Kaplan‒Meier (KM) survival analysis was used to evaluate the prognostic value of the prediction score generated by the radiomics–clinical model.ResultsThe fused model achieved area under the receiver operating characteristic curve values of 0.91 ± 0.01, 0.89 ± 0.02 and 0.85 ± 0.05 on the training and two validation cohorts, respectively. Through KM survival analysis, the risk score generated by our model achieved a significant prognostic value for BM-free survival (BMFS) and overall survival (OS) in the two cohorts (P < 0.05).ConclusionsOur results demonstrated that (1) the fusion of radiomics and clinical features can improve the prediction performance in predicting BM risk, (2) the radiomics model generates higher performance than the clinical model, and (3) the radiomics-clinical fusion model has prognostic value in predicting the BMFS and OS of NSCLC patients.

Predictive value of metabolic parameters derived from preoperative 18F-FDG positron emission tomography/computed tomography for brain metastases in patients with surgically resected non-small cell lung cancer.

Brain metastases (BMs) are common complications in patients with non-small cell lung cancer (NSCLC). The purpose of this study was to investigate whether the metabolic parameters derived from preoperative 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) can predict BM development in patients with surgically resected NSCLC. We retrospectively reviewed 128 consecutive patients with stage I-IIIA NSCLC who underwent 18F-FDG PET/CT before curative surgery at The First Affiliated Hospital of Jinan University between November 2012 and October 2021. By drawing a volume of interest (VOI), the maximum standardized uptake values (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary tumor as well as the mean SUV (SUVmean) of the liver and arterial blood were measured. The tumor-to-liver SUV ratio (TLR) and tumor-to-blood SUV ratio (TBR) were also calculated. Receiver operating characteristic curve analysis was used to determine the best cut-off values for positron emission tomography (PET) parameters to predict BM-free survival, and Cox proportional hazards regression analysis was used to assess the predictive value of clinical variables and PET parameters. The median follow-up duration for survival patients was 23.4 months, and 15 patients (11.7%) experienced BM as the initial relapse site. The cumulative rates of BM over the course of 1, 2, and 5 years were 4.5%, 10.5%, and 17.5%, respectively. The optimal cut-off values for the prediction of BM-free survival were 7.7, 4.9, and 4.5 for SUVmax, TLR, and TBR, and 5.5 mL and 16.1 for MTV and TLG, respectively. In the Cox proportional hazards model, the risk of BM was significantly associated with TLR [hazard ratio (HR) =10.712; 95% confidence interval (CI): 2.958-38.801; P<0.001] and MTV (HR =3.150; 95% CI: 0.964-10.293; P=0.020) after adjusting for tumor stage, clinicopathological factors, and other PET parameters. Preoperative TLR and MTV of the primary tumor may be helpful in predicting BM development in patients with surgically resected NSCLC. Tumor metabolic parameters may potentially be used to stratify the risk of BM and determine individualized surveillance strategies.

First-site-metastasis pattern in patients with inoperable stage III NSCLC treated with concurrent chemoradiotherapy with or without immune check-point inhibition: a retrospective analysis

Abstract Purpose The aim of this study was to investigate a first-site-metastasis pattern (FSMP) in unresectable stage III NSCLC after concurrent chemoradiotherapy (cCRT) with or without immune checkpoint inhibition (ICI). Methods We defined three patient subgroups according to the year of initial multimodal treatment: A (2011–2014), B (2015–2017) and C (2018–2020). Different treatment-related parameters were analyzed. Observed outcome parameters were brain metastasis-free survival (BMFS), extracranial distant metastasis-free survival (ecDMFS) and distant metastasis-free survival (DMFS). Results 136 patients treated between 2011 and 2020 were included with ≥ 60.0 Gy total dose and concurrent chemotherapy (cCRT); thirty-six (26%) received ICI. Median follow-up was 49.7 (range:0.7–126.1), median OS 31.2 (95% CI:16.4–30.3) months (23.4 for non-ICI vs not reached for ICI patients, p = 0.001). Median BMFS/ecDMFS/DMFS in subgroups A, B and C was 14.9/16.3/14.7 months, 20.6/12.9/12.7 months and not reached (NR)/NR/36.4 months (p = 0.004/0.001/0.016). For cCRT+ICI median BMFS was 53.1 vs. 19.1 months for cCRT alone (p = 0.005). Median ecDMFS achieved 55.2 vs. 17.9 (p = 0.003) and median DMFS 29.5 (95% CI: 1.4–57.6) vs 14.93 (95% CI:10.8–19.0) months (p = 0.031), respectively. Multivariate analysis showed that age over 65 (HR:1.629; p = 0.036), GTV ≥ 78 cc (HR: 2.100; p = 0.002) and V20 ≥ 30 (HR: 2.400; p = 0.002) were negative prognosticators for BMFS and GTV ≥ 78 cc for ecDMFS (HR: 1.739; p = 0.027). After onset of brain metastasis (BM), patients survived 13.3 (95% CI: 6.4–20.2) months and 8.6 months (95% CI: 1.6–15.5) after extracranial-distant-metastasis (ecDM). Patients with ecDM as FSMP reached significantly worse overall survival of 22.1 (range:14.4–29.8) vs. 40.1 (range:18.7–61.3) months (p = 0.034) in the rest of cohort. In contrast, BM as FSMP had no impact on OS. Conclusion This retrospective analysis of inoperable stage III NSCLC patients revealed that age over 65, V20 ≥ 30 and GTV ≥ 78 cc were prognosticators for BMFS and GTV ≥ 78 cc for ecDMFS. ICI treatment led to a significant improvement of BMFS, ecDMFS and DMFS. ecDM as FSMP was associated with significant deterioration of OS, whereas BM as FSMP was not.

IMMU-02. IS DUAL AGENT IMMUNOTHERAPY SHIFTING THE EPIDEMIOLOGY OF MELANOMA BRAIN METASTASES? A REAL-WORLD ANALYSIS AND SINGLE-INSTITUTION VALIDATION

Abstract INTRODUCTION Dual agent immunotherapy (dIT) has been paradigm changing in melanoma brain metastasis (MBM). Recent clinical trials have supported the role of dIT for upfront management of small, asymptomatic MBM. Yet, its potential role in extending brain metastasis free survival and decreasing MBM incidence overall has been inadequately explored. Objective: To compare new brain metastasis incidence, median overall survival (OS), and brain metastasis free survival (BMFS) in melanoma patients treated with dIT versus single immunotherapy (sIT). METHODS A real-world deidentified database collating clinical information from 92 organizations (TriNetX, Inc) was queried. Melanoma patients without brain metastases prior to immunotherapy were stratified by treatment (anti-CTLA4 [sIT] and combination anti-CTLA4/ anti-PD1 [dIT]) and propensity score matched. A complementary single-institution retrospective cohort study analyzed melanoma patients treated from 2012-2019. The incidence of new asynchronous MBMs after immunotherapy initiation was compared. Median OS and BMFS were compared via log-rank tests and Cox proportional-hazards model. RESULTS TriNetX identified 8,686 melanoma patients who received immunotherapy (4,585 dIT; 4,101 sIT). MBM prevalence was 9.6%, and 15.6%, for the dIT and sIT cohorts, respectively (p &amp;lt; 0.0001). DIT was associated with a lower likelihood of developing MBM compared to sIT (OR [95%CI], 0.64 [0.61-0.77]). After propensity score matching on demographics and significant comorbidities, OS was not statistically different between treatment groups. On single-institution analysis, 222 melanoma patients were included (89 dIT; 45 anti-CTLA4; 88 anti-PD1). Patients were predominantly stage III at diagnosis (43%) with PD-L1 expression (51%) and BRAF (43%), and NRAS wildtype (50%) mutational status. BMFS was significantly extended in the dIT cohort compared to the anti-CTLA4 or anti-PD1 alone cohorts (406, 217, 139 days, respectively; p&amp;lt; 0.0001). On Cox-proportional hazards model, no covariates significantly contributed to the BMFS difference. CONCLUSION These data highlight the impact of combination anti-CTL4/ anti-PD1 immunotherapy in decreasing BM incidence in melanoma.

NCMP-01. TREATMENT STRATEGIES IN PATIENTS WITH RENAL CELL CANCER AND BRAIN METASTASES

Abstract BACKGROUND Brain metastases (BM) significantly impact quality of life and survival in patients with metastatic renal cell cancer (mRCC). Based on the International Metastatic RCC Database Consortium (IMDC) risk classification, treatment strategies for patients with mRCC vary from systemic treatment with vascular endothelial growth factor receptor-tyrosine kinase inhibitors (VEGFR-TKIs) and/or immune checkpoint inhibitors (ICIs) to active surveillance (AS). Here, we describe the impact of treatment strategies on survival in patients with RCC and BM. METHODS We conducted a single-center, retrospective cohort study at Erasmus MC Cancer Institute (Rotterdam, Netherlands). All consecutive patients with RCC BM between 2011-2022 were included. Primary outcome was the BM-free survival, i.e. the time between diagnosis of extracranial metastases (ECM) and BM. Secondary outcome was overall survival (OS). RESULTS 46 patients with RCC BM were included: 25 (54.3%) had received prior systemic treatment for ECM, and 21 (45.7%) were treatment naive at diagnosis of BM. IMDC scores (favorable 12% resp. 0%, intermediate 48% resp. 64%, poor 24% resp. 0%, unknown 16% resp. 36%) were not significantly different (p=0.07) between these groups. In 39 (84.8%) of 46 patients, BM were metachronous ( &amp;gt;1 month) after ECM. In these patients (n=39), the median BM-free survival was 22.3 (IQR 5.7-46.7) months and was significantly longer (p=0.02) in previously treated patients (29.0 [IQR 12.6-57.0] months) as compared to treatment naive patients (6.8 [IQR 1.0-7.0] months). However, median OS since ECM diagnosis (39.1 [IQR 16.5-111.5] months) was not significantly different (p=0.62) between previously treated and treatment naive patients. CONCLUSION Patients with RCC who received systemic treatment for ECM prior to BM diagnosis, had a longer BM-free survival as compared to patients without previous systemic treatment. These results emphasize the need for careful evaluation of AS in patients with mRCC, even in patients with a favorable prognostic profile.

EPID-01. ANTINEOPLASTIC, RADIATION, AND SYNCHRONICITY EFFECTS ON BRAIN METASTASIS SURVIVAL: A RETROSPECTIVE POPULATION-BASED STUDY

Abstract INTRODUCTION Brain metastases (BM) are the most common central nervous system tumors. The impact of oncological treatment on the prevention of BM is not well-defined. We report the effects of chemotherapy and radiotherapy directed at primary cancer on synchronous and metachronous BM survival. METHODS A large nationwide multi-institutional claims-based platform (TriNetX Diamond Network) was queried. Patients diagnosed during 2013-2023 with the 15 most common primary cancers that metastasize to the brain were included. Metachronous was defined as BM diagnosed &amp;gt; 2 months after primary cancer. Cohorts were propensity score matched for age, extracranial metastasis, and adjuvant therapy. Kaplan-Meier plots were used to compare survival. RESULTS 113,827 (38%) patients with synchronous and 187,036 (62%) with metachronous BM were identified. Patients with synchronous BM had 26 months shorter median survival compared to metachronous BM (11 vs. 37 months, HR 2.17, 95%CI 2.14-2.19, P&amp;lt; 0.0001). However, no survival advantage was observed from the time of BM diagnosis (11 vs. 12 months, HR 1.06, 95%CI 1.05-1.08, P=0.411). Antineoplastic treatment prior to BM improved median BM-free survival by 13 months (4 vs. 18 months, HR 1.66, 95%CI 1.77-1.82, P &amp;lt; 0.0001) and median OS by 17 months (25.15 vs. 42.26 months, HR 1.48, 95%CI 1.46-1.51, P&amp;lt; 0.0001). Radiation therapy prior to BM incurred a significant but smaller increase in median BM-free survival by 6 months (5 vs. 11 months, HR 1.27, 95%CI 1.26-1.29, P&amp;lt; 0.0001) and median OS by about 3 months (30.13 vs. 32.82 months, HR 1.06, 95%CI 1.04-1.08, P &amp;lt; 0.0001). CONCLUSION Once BM is diagnosed, the synchronicity of diagnosis does not predict survival. Antineoplastic and radiation treatment directed at primary cancer may improve BM-free survival and OS. Studies characterizing the BM-free effects of molecular markers, chemotherapy, and radiotherapy are necessary to improve screening, prevention, and treatment.

Role and Modality of Combining Radiotherapy with Immunotherapy in Stage III-IV Unresectable Small Cell Lung Cancer

The combination of radiotherapy and immunotherapy was rarely reported in the management of small cell lung cancer (SCLC). We retrospectively assessed the role and modality of this combination in Stage III-IV unresectable SCLC. Patients with stage III and IV SCLC were enrolled according to AJCC 8th edition. Both efficacy and safety of immunotherapy combined with radiotherapy were evaluated. Thereinto, patients received first-line chemo-immunotherapy and sequential thoracic consolidation radiotherapy (TCRT) were further evaluated. Survival and descriptive analyses were performed. Between January 1, 2019 and December 31, 2021, 51 patients were included in our analysis. Median follow-up was 28.0 months (95% CI 22.8-33.2). Patients received radiotherapy in treatment course had a prolonged 2-year overall survival (OS). And in the first-line immunotherapy cohort of 27 patients, the addition of TCRT significantly improved 2y-OS (72.22% vs. 13.89%, p = 0.0048), 2y-locoregional recurrence free survival (LRRFS) (90.00% vs 48.00%, p = 0.011), and 2y-distance progression free survival (DPFS) (66.67% vs. 16.67%, p = 0.039). Subgroup analyses showed that TCRT rendered superior outcomes regardless of brain metastases. Dose-escalation (45 Gy/15f) and earlier radiotherapy seemed to improve the benefit. Of 70.37% (19/27) patients experienced disease progression in the TCRT evaluation cohort, 63.16% (12/19) patients failed in brain. A tendency toward better OS and superior brain metastases free survival (BMFS) were observed after receiving prophylactic cranial irradiation (PCI). Finally, the most common grade 2 or higher toxic effects were pneumonitis in all patients (11.76% of immune-related vs. 7.84% of radiation related). Earlier addition of TCRT to immunotherapy could significantly improve survival and extracranial control for stage IIIA-IVB unresectable SCLC patients, with no increased risk of adverse events. In the era of immunotherapy, PCI may still be a recommended strategy. Further investigation is warranted.

Extrapulmonary Small Cell Carcinoma: A Single Institution Review of Brain Metastases, Treatment Paradigms and Patient Outcomes

Extrapulmonary small cell carcinoma (EPSCC) is a rare entity with 1,000 cases reported annually in the U.S. It can originate in a variety of sites outside of the lung, and even with locoregional disease, relapse is common, and survival is poor. Prophylactic cranial irradiation (PCI) can improve survival in small cell lung carcinoma, however in the setting of EPSCC its role has not been clearly defined. We offer a single institution retrospective review of EPSCC, outlining the incidence of brain metastases, treatment paradigms, and patient outcomes. Patients with available records were identified from an institutional database. Demographic, disease-related, and treatment details were abstracted from the electronic medical record. Clinical outcomes were obtained by medical record review and brain metastases were identified through diagnostic imaging. Patients were classified as having brain metastases at diagnosis or in follow-up. Brain metastasis-free survival (BMFS) was defined as the duration of time from diagnosis to the development of brain metastases, and extracranial progression-free survival (ePFS), as the duration of time from diagnosis to progression of disease outside the brain. Time to event outcomes were summarized using the Kaplan-Meier method. Analyses were performed using R version 3.6. In total, 68 patients met eligibility criteria for analysis. The majority were male (66%) and median age was 68. The most common primary sites were genitourinary (32%) and gastrointestinal/hepatobiliary (22%). Thirty-eight patients (56%) had diagnostic brain imaging at time of diagnosis, with brain metastases present in 5 (13%). Treatment was delivered to 53 patients (80%) and treatment modalities included chemotherapy (n = 46), radiotherapy (n = 21), and surgery (n = 18). Median follow-up was 9.3 months for all patients and 10.3 months for surviving patients. Overall, 12 patients were observed to have brain metastases: 5 at diagnosis and 7 in follow-up. The competing risk of death without brain metastases at 1 year was 51.5%. Four of 5 patients with de novo brain metastases received WBRT. Of the 7 patients with subsequent brain metastases, 1 received salvage WBRT and 3 received salvage SRS. In total, 49 patients died and median OS was 10.0 months. Those with brain metastases had no significant difference in OS when compared to those without brain metastases (10.8 months v. 9.4 months). There was no association between primary type and survival. EPSCC is a rare entity that is most commonly diagnosed in the genitourinary system. In contrast to SCLC, the incidence of brain metastases is uncommon. No difference in survival was observed between patients with or without brain metastases. While retrospective studies must be interpreted with caution, our data suggest that the risks of PCI may outweigh the benefits. Further studies investigating the role of brain imaging surveillance, as well as the optimal management of brain metastases, is warranted.

The long transcript of lncRNA TMPO-AS1 promotes bone metastases of prostate cancer by regulating the CSNK2A1/DDX3X complex in Wnt/β-catenin signaling

The second most common male cancer is prostate cancer (PCa), which has a high tendency for bone metastasis. Long non-coding RNAs, including TMPO-AS1, play a crucial role in PCa progression. However, TMPO-AS1’s function in PCa bone metastasis (BM) and its underlying molecular mechanisms are unclear. Herein, we found that the long transcript of TMPO-AS1 (TMPO-AS1L) was upregulated in PCa tissues with bone metastasis, and overexpression of TMPO-AS1L correlated with advanced clinicopathological features and reduced BM-free survival in patients with PCa. Upregulated TMPO-AS1L promoted, whereas downregulated TMPO-AS1L inhibited, the PCa cell bone metastatic capacity in vitro and in vivo. Mechanistically, TMPO-AS1L was demonstrated to act as a scaffold, that strengthened the interaction of casein kinase 2 alpha 1 (CSNK2A1) and DEAD-box helicase 3 X-linked (DDX3X), and activated the Wnt/β-catenin signaling pathway, thus promoting BM of PCa. Moreover, upregulation of TMPO-AS1L in PCa resulted from transcription elongation modulated by general transcription factor IIF subunit 2 (GTF2F2). Collectively, our study provides critical insights into the role of TMPO-AS1L in PCa BM via Wnt/β-catenin signaling, identifying TMPO-AS1L as a candidate marker of PCa bone metastasis prognosis and therapeutic target.

CLRM-09 MAPPING THE DISTRIBUTION AND CLINICAL ASSOCIATIONS OF BRAIN METASTASES IN RENAL CELL CARCINOMA

Abstract Brain metastases (BrM) commonly occur in renal cell carcinoma (RCC) and often present with hemorrhagic features. The distribution patterns of BrM in RCC and their associations with clinical outcomes remain unclear. We conducted a retrospective neuroanatomical distribution analysis combined with clinical review of our surgical RCC BrM cohort. Sixty-seven BrMs from 46patients (age 63±10years, 25males) were included. The majority of BrM (55%) were found in the left hemisphere, with frontal (45%), parietal (21%), and occipital (18%) lobes being the most commonly affected areas. Hemosiderin deposits, as detected by MRI, were present in 82% of BrM, while hemorrhage, as detected by CT, was present in 80% of BrM. Patients with solitary BrM had a higher KPS (p=0.006) and lower disease burden (p=0.004) compared to those with multiple BrM. Mean 1D and 2D(RANO) tumor dimensions were 2.0±1.1cm and 4.7±4.9cm2, respectively, and correlated with the neutrophil count at BrM diagnosis (r=0.3; p=0.01). Hemosiderin deposits were associated with larger tumors (2.6±1.0cm vs. 1.8±0.7cm, p=0.04), lower platelet counts (p=0.01), and higher hemoglobin levels (p=0.08). Shorter Brain Metastasis-Free Survival was associated with hemosiderin deposits on MRI (log-rank p=0.04) and renal vein thrombosis (RVT) in the primary specimen (log-rank p=0.002). RVT at primary diagnosis was associated with both hemosiderin deposits on MRI (p=0.05) and hemorrhage on CT (p=0.03), and CNS progression-free survival was shorter in patients with RVT (7.3±1.7 months vs. 21.0±4.7 months). When including only significant predictors, right hemispheric BrM lateralization (HR 2.6, p=0.06), hemosiderin deposits in BrM (HR 6.5, p=0.02), and IMDC risk groups (intermediate HR=2.9; poor-risk HR=25.6; p&amp;lt;0.04) were independent prognostic factors for shorter OS on multivariable analysis. Our results demonstrate that mapping the BrM distribution o in RCC can provide clinically relevant insights. Hemosiderin deposits in BrM may have prognostic implications. Further analyses are ongoing.

Prophylactic cranial irradiation effect on survival in patients with small cell lung cancer: a comprehensive systematic review and meta-analysis.

Prophylactic cranial irradiation (PCI) is a companion treatment option for small cell lung cancer (SCLC) patients. However, its efficacy and associated risk factors have not been clearly defined. In this study, the authors aimed to systematically assess the effectiveness and role of PCI in the treatment plan of SCLC. The PubMed, Scopus, Web of Science, and Cochrane databases were searched using the following key terms and their equivalents: "brain," "radiotherapy," "metastases," "prophylactic," and "small cell lung cancer." Studies comparing overall survival (OS), progression-free survival (PFS), brain metastasis-free survival (BMFS), and incidence of brain metastases between patients receiving PCI and those not receiving it were considered eligible. Risk of bias was assessed using the Risk of Bias in Non-Randomized Studies-of Interventions (ROBINS-I) tool. Meta-analysis was conducted on the mentioned outcomes with subgrouping based on different factors. The authors identified 74 studies published between 1983 and 2022 with 31,551 SCLC patients, of whom 26.7% received PCI. The studies were a mix of prospective randomized and retrospective observational studies. Patients with limited-stage disease receiving PCI had better OS, PFS, and BMFS than those not receiving PCI. Patients receiving PCI also had significantly longer OS times and developed brain metastases significantly later. However, findings regarding extensive-stage SCLC were not as promising. PCI is an effective option for limited-stage SCLC patients. It improves OS and PFS, delays brain metastases, and reduces the incidence of brain metastases. However, it might not benefit patients with extensive-stage SCLC under adequate follow-up with MRI surveillance. Finally, the heterogeneity of the included studies and publication bias were the main limitations of this study.

Epidemiology and survival outcomes of synchronous and metachronous brain metastases: a retrospective population-based study.

Brain metastases (BMs) are the most common CNS tumors, yet their prevalence is difficult to determine. Most studies only report synchronous metastases, which make up a fraction of all BMs. The authors report the incidence and prognosis of patients with synchronous and metachronous BMs over a decade. Study data were obtained from the TriNetX Research Network. Patients were included if they had a primary cancer diagnosis and a BM diagnosis, with primary cancer occurring between January 1, 2013, and January 1, 2023. Metachronous BM was defined as BM diagnosed more than 2 months after the primary cancer. Cohorts were balanced by propensity score matching for age, extracranial metastasis, and antineoplastic or radiation therapy. Kaplan-Meier plots were used to evaluate survival differences between synchronous and metachronous BMs and associations with clinical conditions. A log-rank test was used to evaluate BM-free survival for metachronous BM and overall survival (OS) for all BMs. Hazard ratios and 95% CIs were calculated. Of the 11,497,663 patients with 15 primary cancers identified, 300,863 (2.6%) developed BMs. BMs most commonly arose from lung and breast cancers and melanoma. Of all BMs, 113,827 (37.8%) presented synchronously and 187,036 (62.2%) presented metachronously. Lung and bronchial cancer had the highest metastasis rate (11.0%) and the highest synchronous presentation (51.0%). For metachronous presentations, the time from primary diagnosis to metastasis ranged from 1.3 to 2.5 years, averaging 1.8 years. Metachronous BM diagnosis was associated with longer survival over synchronous BM from primary diagnosis (11.54 vs 37.41 months, p < 0.0001), but shorter survival than extracranial metastases without BM (38.75 vs 69.18 months, p < 0.0001). Antineoplastic therapy prior to BM was associated with improved BM-free survival (4.46 vs 17.80 months, p < 0.0001) and OS (25.15 vs 42.26 months, p < 0.0001). Radiotherapy showed a similar effect that was statistically significant but modest for BM-free survival (5.25 vs 11.44 months, p < 0.0001) and OS (30.13 vs 32.82 months, p < 0.0001). The majority of BMs present metachronously and arise within 2 years of primary cancer diagnosis. The substantial rate of BMs presenting within 6 months of primary cancer, especially liver, lung, and pancreatic cancer, may guide future recommendations on intracranial staging. Antineoplastic therapy prior to the development of BM may prolong the time before metastasis and improve survival. Further characterization of this population can better inform screening, prevention, and treatment efforts.