Evaluation of Culture Conducive to Academic Success by Gender at a Comprehensive Cancer Center

INTRODUCTION

The primary objective of this study was to determine whether workplace culture in academic oncology differed by gender, during the COVID-19 pandemic.

MATERIALS AND METHODS

We used the Culture Conducive to Women's Academic Success (CCWAS), a validated survey tool, to investigate the academic climate at an NCI-designated Cancer Center. We adapted the CCWAS to be applicable to people of all genders. The full membership of the Cancer Center was surveyed (total faculty = 429). The questions in each of 4 CCWAS domains (equal access to opportunities, work-life balance, freedom from gender bias, and leadership support) were scored using a 5-point Likert scale. Median score and interquartile ranges for each domain were calculated.

RESULTS

A total of 168 respondents (men = 58, women = 106, n = 4 not disclosed) submitted survey responses. The response rate was 39% overall and 70% among women faculty. We found significant differences in perceptions of workplace culture by gender, both in responses to individual questions and in the overall score in the following domains: equal access to opportunities, work-life balance, and leader support, and in the total score for the CCWAS.

CONCLUSIONS

Our survey is the first of its kind completed during the COVID-19 pandemic at an NCI-designated Cancer Center, in which myriad factors contributed to burnout and workplace challenges. These results point to specific issues that detract from the success of women pursuing careers in academic oncology. Identifying these issues can be used to design and implement solutions to improve workforce culture, mitigate gender bias, and retain faculty.

A combinatory vaccine with IMA950 plus varlilumab promotes effector memory T-cell differentiation in the peripheral blood of patients with low-grade gliomas

BACKGROUND

Central nervous system (CNS) WHO grade 2 low-grade glioma (LGG) patients are at high risk for recurrence and with unfavorable long-term prognosis due to the treatment resistance and malignant transformation to high-grade glioma. Considering the relatively intact systemic immunity and slow-growing nature, immunotherapy may offer an effective treatment option for LGG patients.

METHODS

We conducted a prospective, randomized pilot study to evaluate the safety and immunological response of the multipeptide IMA950 vaccine with agonistic anti-CD27 antibody, varlilumab, in CNS WHO grade 2 LGG patients. Patients were randomized to receive combination therapy with IMA950 + poly-ICLC and varlilumab (Arm 1) or IMA950 + poly-ICLC (Arm 2) before surgery, followed by adjuvant vaccines.

RESULTS

A total of 14 eligible patients were enrolled in the study. Four patients received pre-surgery vaccines but were excluded from postsurgery vaccines due to the high-grade diagnosis of the resected tumor. No regimen-limiting toxicity was observed. All patients demonstrated a significant increase of anti-IMA950 CD8+ T-cell response postvaccine in the peripheral blood, but no IMA950-reactive CD8+ T cells were detected in the resected tumor. Mass cytometry analyses revealed that adding varlilumab promoted T helper type 1 effector memory CD4+ and effector memory CD8+ T-cell differentiation in the PBMC but not in the tumor microenvironment.

CONCLUSION

The combinational immunotherapy, including varlilumab, was well-tolerated and induced vaccine-reactive T-cell expansion in the peripheral blood but without a detectable response in the tumor. Further developments of strategies to overcome the blood-tumor barrier are warranted to improve the efficacy of immunotherapy for LGG patients.

Genomic alterations associated with postoperative nodular leptomeningeal disease after resection of brain metastases

OBJECTIVE

The relationship between brain metastasis resection and risk of nodular leptomeningeal disease (nLMD) is unclear. This study examined genomic alterations found in brain metastases with the aim of identifying alterations associated with postoperative nLMD in the context of clinical and treatment factors.

METHODS

A retrospective, single-center study was conducted on patients who underwent resection of brain metastases between 2014 and 2022 and had clinical and genomic data available. Postoperative nLMD was the primary endpoint of interest. Targeted next-generation sequencing of > 500 oncogenes was performed in brain metastases. Cox proportional hazards analyses were performed to identify clinical features and genomic alterations associated with nLMD.

RESULTS

The cohort comprised 101 patients with tumors originating from multiple cancer types. There were 15 patients with nLMD (14.9% of the cohort) with a median time from surgery to nLMD diagnosis of 8.2 months. Two supervised machine learning algorithms consistently identified CDKN2A/B codeletion and ERBB2 amplification as the top predictors associated with postoperative nLMD across all cancer types. In a multivariate Cox proportional hazards analysis including clinical factors and genomic alterations observed in the cohort, tumor volume (× 10 cm3; HR 1.2, 95% CI 1.01-1.5; p = 0.04), CDKN2A/B codeletion (HR 5.3, 95% CI 1.7-16.9; p = 0.004), and ERBB2 amplification (HR 3.9, 95% CI 1.1-14.4; p = 0.04) were associated with a decreased time to postoperative nLMD.

CONCLUSIONS

In addition to increased resected tumor volume, ERBB2 amplification and CDKN2A/B deletion were independently associated with an increased risk of postoperative nLMD across multiple cancer types. Additional work is needed to determine if targeted therapy decreases this risk in the postoperative setting.

Provider Perceptions of a Novel Inpatient Co-Rounding Model Integrating Medical Oncology, Neuro-Oncology, and Radiation Oncology for the Care of Patients with Advanced Cancer

PURPOSE/OBJECTIVE(S)

Patients (pts) with advanced cancer require interdisciplinary care. Although tumor boards are well-established in the outpatient setting, few studies have evaluated interventions for improving consultative care coordination for hospitalized pts with cancer. The purpose of this study was to evaluate a novel inpatient co-rounding model of care in which medical-, neuro-, and radiation-oncology consult teams rounded jointly, with the hypothesis that primary referring team perception of the alignment of the recommendations from these consult services would improve post-implementation.

MATERIALS/METHODS

An inpatient co-rounding model was implemented in September 2021 for hospitalized pts with solid malignancies at a tertiary medical center. Attending physicians, nurse practitioners, fellows, and residents from oncologic consulting services met virtually twice weekly to discuss pt care. Providers from the two most common primary services for pts with cancer at this hospital (hospital medicine and neurosurgery) were surveyed via institutional email listservs. The survey included Likert-type questions about the quality of inpatient consultation and the alignment of recommendations across three consulting oncological specialty services. The pre-intervention survey was distributed prior to model implementation, and the post-intervention survey was distributed 9 months later. Wilcoxon rank-sum tests were used to compare responses from the pre-and post-intervention surveys.

RESULTS

At each session, a median of 6 providers attended (range, 4-8 providers), and a median of 6 pts were discussed (range, 4-8 pts). Among 331 providers surveyed, 119 completed the pre-intervention survey (36% response rate), and 34 completed the post-intervention survey (10% response rate). Respondents were 81 (53%) internal medicine attending physicians/hospitalists, 55 (36%) internal medicine resident physicians, 6 (4%) neurosurgery advanced practice providers, 6 (4%) neurosurgery attending physicians, and 5 (3%) neurosurgery resident physicians. When asked to rate agreement with the statement that consultant recommendations from medical-, neuro-, and radiation-oncology were aligned, respondents were significantly more likely to perceive alignment 9 months post-implementation (67% strongly agree) compared to pre-implementation (23% strongly agree, p = 0.0001). There was high satisfaction with the quality of medical-, neuro-, and radiation-oncology consultations at both time points, with no statistical difference pre- vs. post-implementation of the co-rounding model.

CONCLUSION

A novel inpatient co-rounding model of care was successfully launched between medical-, neuro-, and radiation-oncology. Primary teams perceived greater alignment in recommendations between these consulting services after project implementation. Future directions include evaluating the impact of this co-rounding model on patient outcomes.

Association of CDKN2A alterations with increased postoperative seizure risk after resection of brain metastases

OBJECTIVE

Seizures are common and significantly disabling for patients with brain metastases (BMs). Although resection can provide seizure control, a subset of patients with BMs may continue to suffer seizures postoperatively. Genomic BM characteristics may influence which patients are at risk for postoperative seizures. This work explores correlations between genomic alterations and risk of postoperative seizures following BM resection.

METHODS

All patients underwent BM resection at a single institution, with available clinical and sequencing data on more than 500 oncogenes. Clinical seizures were documented pre- and postoperatively. A random forest machine learning classification was used to determine candidate genomic alterations associated with postoperative seizures, and clinical and top genomic variables were correlated with postoperative seizures by using Cox proportional hazards models.

RESULTS

There were 112 patients with BMs who underwent 114 surgeries and had at least 1 month of postoperative follow-up. Seizures occurred preoperatively in 26 (22.8%) patients and postoperatively in 25 (21.9%). The Engel classification achieved at 6 months for those with preoperative seizures was class I in 13 (50%); class II in 6 (23.1%); class III in 5 (19.2%), and class IV in 2 (7.7%). In those with postoperative seizures, only 8 (32.0%) had seizures preoperatively, and preoperative seizures were not a significant predictor of postoperative seizures (HR 1.84; 95% CI 0.79-4.37; p = 0.156). On random forest classification and multivariate Cox analysis controlling for factors including recurrence, extent of resection, and number of BMs, CDKN2A alterations were associated with postoperative seizures (HR 3.22; 95% CI 1.27-8.16; p = 0.014). Melanoma BMs were associated with higher risk of postoperative seizures compared with all other primary malignancies (HR 5.23; 95% CI 1.37-19.98; p = 0.016). Of 39 BMs with CDKN2A alteration, 35.9% (14/39) had postoperative seizures, compared to 14.7% (11/75) without CDKN2A alteration. The overall rate of postoperative seizures in melanoma BMs was 42.9% (15/35), compared with 12.7% (10/79) for all other primary malignancies.

CONCLUSIONS

CDKN2A alterations and melanoma primary malignancy are associated with increased postoperative seizure risk following resection of BMs. These results may help guide postoperative seizure prophylaxis in patients undergoing resection of BMs.

Genomic alterations associated with rapid progression of brain metastases

OBJECTIVE

The aim of this study was to investigate associations between genomic alterations in resected brain metastases and rapid local and distant CNS recurrence identified at the time of postoperative adjuvant radiosurgery.

METHODS

This was a retrospective study on patients who underwent resection of intracranial brain metastases. Next-generation sequencing of more than 500 coding genes was performed on brain metastasis specimens. Postoperative and preradiosurgery MR images were compared to identify rapid recurrence. Genomic data were associated with rapid local and distant CNS recurrence of brain metastases using nominal regression analyses.

RESULTS

The cohort contained 92 patients with 92 brain metastases. Thirteen (14.1%) patients had a rapid local recurrence, and 64 (69.6%) patients had rapid distant CNS progression by the time of postoperative adjuvant radiosurgery, which occurred in a median time of 25 days (range 3-85 days) from surgery. RB1 and CTNNB1 mutations were seen in 8.7% and 9.8% of the cohort, respectively, and were associated with a significantly higher risk of rapid local recurrence (RB1: OR 13.6, 95% CI 2.0-92.39, p = 0.008; and CTNNB1: OR 11.97, 95% CI 2.25-63.78, p = 0.004) on multivariate analysis. No genes were found to be associated with rapid distant CNS progression. However, the presence of extracranial disease was significantly associated with a higher risk of rapid distant recurrence on multivariate analysis (OR 4.06, 95% CI 1.08-15.34, p = 0.039).

CONCLUSIONS

Genomic alterations in RB1 or CTNNB1 were associated with a significantly higher risk of rapid recurrence at the resection site. Although no genomic alterations were associated with rapid distant recurrence, having active extracranial disease was a risk factor for new lesions by the time of adjuvant radiotherapy after resection.

Molecular Features of Resected Melanoma Brain Metastases, Clinical Outcomes, and Responses to Immunotherapy

Importance

Central nervous system (CNS)-penetrant systemic therapies have significantly advanced care for patients with melanoma brain metastases. However, improved understanding of the molecular landscape and microenvironment of these lesions is needed to both optimize patient selection and advance treatment approaches.

Objective

To evaluate how bulk and single-cell genomic features of melanoma brain metastases are associated with clinical outcome and treatment response.

Design, Setting, and Participants

This cohort study analyzed bulk DNA sequencing and single nuclear RNA-sequencing data from resected melanoma brain metastases and included 94 consecutive patients with a histopathologically confirmed diagnosis of melanoma brain metastasis who underwent surgical resection at a single National Comprehensive Cancer Network cancer center in San Francisco, California, from January 1, 2009, to December 31, 2022.

Exposure

A Clinical Laboratory Improvement Amendments-certified targeted sequencing assay was used to analyze tumor resection specimens, with a focus on BRAF V600E alteration. For frozen pathologic specimens from CNS treatment-naive patients undergoing surgical resection, commercial single nuclear RNA sequencing approaches were used.

Main Outcomes and Measures

The primary outcome was overall survival (OS). Secondary outcomes included CNS progression-free survival (PFS), microenvironmental composition with decreased T-cell and macrophage populations, and responses to immunotherapy.

Results

To correlate molecular status with clinical outcome, Kaplan-Meier survival analysis of 94 consecutive patients (median age, 64 years [range, 24-82 years]; 70 men [74%]) with targeted BRAF alteration testing showed worse median intracranial PFS (BRAF variant: 3.6 months [IQR, 0.1-30.6 months]; BRAF wildtype: 11.0 months [IQR, 0.8-81.5 months]; P < .001) and OS (BRAF variant: 9.8 months [IQR, 2.5-69.4 months]; BRAF wildtype: 23.2 months [IQR, 1.1-102.5 months]; P = .005; log-rank test) in BRAF V600E variant tumors. Multivariable Cox proportional hazards regression analysis revealed that BRAF V600E status was an independent variable significantly associated with both PFS (hazard ratio [HR], 2.65; 95% CI, 1.54-4.57; P < .001) and OS (HR, 1.96; 95% CI, 1.08-3.55; P = .03). For the 45 patients with resected melanoma brain metastases undergoing targeted DNA sequencing, molecular classification recapitulated The Cancer Genome Atlas groups (NRAS variant, BRAF variant, NF1 variant, and triple wildtype) with no subtype enrichment within the brain metastasis cohort. On a molecular level, BRAF V600E variant lesions were found to have a significantly decreased tumor mutation burden. Moreover, single nuclear RNA sequencing of treatment-naive BRAF V600E variant (n = 3) brain metastases compared with BRAF wildtype (n = 3) brain metastases revealed increased immune cell populations in BRAF wildtype tumors (mean [SD], 11% [4.1%] vs 3% [1.6%] CD45-positive cells; P = .04). Survival analysis of postoperative immunotherapy responses by BRAF status revealed that BRAF wildtype lesions were associated with a response to checkpoint inhibition (median OS: with immunotherapy, undefined; without immunotherapy, 13.0 months [range, 1.1-61.7 months]; P = .001; log-rank test) while BRAF variant lesions (median OS: with immunotherapy, 9.8 months [range, 2.9-39.8 months]; without immunotherapy, 9.5 months [range, 2.5-67.2 months]; P = .81; log-rank test) were not.

Conclusions and Relevance

This molecular analysis of patients with resected melanoma brain metastases found that BRAF V600E alteration is an important translational biomarker associated with worse clinical outcomes, differential microenvironmental composition, and benefit from immunotherapy. Patients with BRAF V600E variant melanoma brain metastases may thus benefit from alternative CNS-penetrant systemic regimens.

Oncolytic DNX-2401 virotherapy plus pembrolizumab in recurrent glioblastoma: a phase 1/2 trial

Immune-mediated anti-tumoral responses, elicited by oncolytic viruses and augmented with checkpoint inhibition, may be an effective treatment approach for glioblastoma. Here in this multicenter phase 1/2 study we evaluated the combination of intratumoral delivery of oncolytic virus DNX-2401 followed by intravenous anti-PD-1 antibody pembrolizumab in recurrent glioblastoma, first in a dose-escalation and then in a dose-expansion phase, in 49 patients. The primary endpoints were overall safety and objective response rate. The primary safety endpoint was met, whereas the primary efficacy endpoint was not met. There were no dose-limiting toxicities, and full dose combined treatment was well tolerated. The objective response rate was 10.4% (90% confidence interval (CI) 4.2-20.7%), which was not statistically greater than the prespecified control rate of 5%. The secondary endpoint of overall survival at 12 months was 52.7% (95% CI 40.1-69.2%), which was statistically greater than the prespecified control rate of 20%. Median overall survival was 12.5 months (10.7-13.5 months). Objective responses led to longer survival (hazard ratio 0.20, 95% CI 0.05-0.87). A total of 56.2% (95% CI 41.1-70.5%) of patients had a clinical benefit defined as stable disease or better. Three patients completed treatment with durable responses and remain alive at 45, 48 and 60 months. Exploratory mutational, gene-expression and immunophenotypic analyses revealed that the balance between immune cell infiltration and expression of checkpoint inhibitors may potentially inform on response to treatment and mechanisms of resistance. Overall, the combination of intratumoral DNX-2401 followed by pembrolizumab was safe with notable survival benefit in select patients (ClinicalTrials.gov registration: NCT02798406).

Interactive Effects of Molecular, Therapeutic, and Patient Factors on Outcome of Diffuse Low-Grade Glioma

PURPOSE

In patients with diffuse low-grade glioma (LGG), the extent of surgical tumor resection (EOR) has a controversial role, in part because a randomized clinical trial with different levels of EOR is not feasible.

METHODS

In a 20-year retrospective cohort of 392 patients with IDH-mutant grade 2 glioma, we analyzed the combined effects of volumetric EOR and molecular and clinical factors on overall survival (OS) and progression-free survival by recursive partitioning analysis. The OS results were validated in two external cohorts (n = 365). Propensity score analysis of the combined cohorts (n = 757) was used to mimic a randomized clinical trial with varying levels of EOR.

RESULTS

Recursive partitioning analysis identified three survival risk groups. Median OS was shortest in two subsets of patients with astrocytoma: those with postoperative tumor volume (TV) > 4.6 mL and those with preoperative TV > 43.1 mL and postoperative TV ≤ 4.6 mL. Intermediate OS was seen in patients with astrocytoma who had chemotherapy with preoperative TV ≤ 43.1 mL and postoperative TV ≤ 4.6 mL in addition to oligodendroglioma patients with either preoperative TV > 43.1 mL and residual TV ≤ 4.6 mL or postoperative residual volume > 4.6 mL. Longest OS was seen in astrocytoma patients with preoperative TV ≤ 43.1 mL and postoperative TV ≤ 4.6 mL who received no chemotherapy and oligodendroglioma patients with preoperative TV ≤ 43.1 mL and postoperative TV ≤ 4.6 mL. EOR ≥ 75% improved survival outcomes, as shown by propensity score analysis.

CONCLUSION

Across both subtypes of LGG, EOR beginning at 75% improves OS while beginning at 80% improves progression-free survival. Nonetheless, maximal resection with preservation of neurological function remains the treatment goal. Our findings have implications for surgical strategies for LGGs, particularly oligodendroglioma.

Identification of risk factors associated with leptomeningeal disease after resection of brain metastases

OBJECTIVE

Resection of brain metastases (BMs) may be associated with increased risk of leptomeningeal disease (LMD). This study examined rates and predictors of LMD, including imaging subtypes, in patients who underwent resection of a BM followed by postoperative radiation.

METHODS

A retrospective, single-center study was conducted examining overall LMD, classic LMD (cLMD), and nodular LMD (nLMD) risk. Logistic regression, Cox proportional hazards, and random forest analyses were performed to identify risk factors associated with LMD.

RESULTS

Of the 217 patients in the cohort, 47 (21.7%) developed postoperative LMD, with 19 cases (8.8%) of cLMD and 28 cases (12.9%) of nLMD. Six-, 12-, and 24-month LMD-free survival rates were 92.3%, 85.6%, and 71.4%, respectively. Patients with cLMD had worse survival outcomes from the date of LMD diagnosis compared with nLMD (median 2.4 vs 6.9 months, p = 0.02, log-rank test). Cox proportional hazards analysis identified cerebellar/insular/occipital location (hazard ratio [HR] 3.25, 95% confidence interval [CI] 1.73-6.11, p = 0.0003), absence of extracranial disease (HR 2.49, 95% CI 1.27-4.88, p = 0.008), and ventricle contact (HR 2.82, 95% CI 1.5-5.3, p = 0.001) to be associated with postoperative LMD. A predictive model using random forest analysis with an area under the receiver operating characteristic curve of 0.87 in a test cohort identified tumor location, systemic disease status, and tumor volume as the most important factors associated with LMD.

CONCLUSIONS

Tumor location, absence of extracranial disease at the time of surgery, ventricle contact, and increased tumor volume were associated with LMD. Further work is needed to determine whether escalating therapies in patients at risk of LMD prevents disease dissemination.

CDKN2A/B co-deletion is associated with increased risk of local and distant intracranial recurrence after surgical resection of brain metastases

Background

While genetic alterations in brain metastases (BMs) have been previously explored, there are limited data examining their association with recurrence after surgical resection. This study aimed to identify genetic alterations within BMs associated with CNS recurrence after surgery across multiple cancer types.

Methods

A retrospective, single-center study was conducted with patients who underwent resection of a BM with available clinical and gene sequencing data available. Local and remote CNS recurrence were the primary study outcomes. Next-generation sequencing of the coding regions in over 500 oncogenes was performed in brain metastasis specimens. Cox proportional hazards analyses were performed to identify clinical features and genomic alterations associated with CNS recurrence.

Results

A total of 90 patients undergoing resection of 91 BMs composed the cohort. Genes most frequently mutated in the cohort included TP53 (64%), CDKN2A (37%), TERT (29%), CDKN2B (23%), NF1 (14%), KRAS (14%), and PTEN (13%), all of which occurred across multiple cancer types. CDKN2A/B co-deletion was seen in 21 (23.1%) brain metastases across multiple cancer types. In multivariate Cox proportional hazard analyses including patient, tumor, and treatment factors, CDKN2A/B co-deletion in the brain metastasis was associated with increased risk of local (HR 4.07, 95% CI 1.32-12.54, P = 0.014) and remote (HR 2.28, 95% CI 1.11-4.69, P = 0.025) CNS progression. Median survival and length of follow-up were not different based on CDKN2A/B mutation status.

Conclusions

CDKN2A/B co-deletion detected in BMs is associated with increased CNS recurrence after surgical resection. Additional work is needed to determine whether more aggressive treatment in patients with this mutation may improve outcomes.

Factors associated with preoperative and postoperative seizures in patients undergoing resection of brain metastases

OBJECTIVE

Epileptic seizures are a common and potentially devastating complication of metastatic brain tumors. Although tumor-related seizures have been described in previous case series, most studies have focused on primary brain tumors and have not differentiated between different types of cerebral metastases. The authors analyzed a large surgical cohort of patients with brain metastases to examine risk factors associated with preoperative and postoperative seizures and to better understand the seizure risk factors of metastatic brain tumors.

METHODS

Patients who underwent resection of a brain metastasis at the University of California, San Francisco (UCSF), were retrospectively reviewed. Patients included in the study were ≥ 18 years of age, required resection of a brain metastasis, and were treated at UCSF. Primary cancers included melanoma, non-small cell lung adenocarcinoma, breast adenocarcinoma, colorectal adenocarcinoma, esophageal adenocarcinoma, gastric adenocarcinoma, renal cell carcinoma, urothelial carcinoma, ovarian carcinoma, cervical squamous cell carcinoma, and endometrial adenocarcinoma. Patients were evaluated for primary cancer type and seizure occurrence, as well as need for use of antiepileptic drugs preoperatively, at time of discharge, and at 6 months postoperatively. Additionally, Engel classification scores were assigned to those patients who initially presented with seizures preoperatively. Univariate and multivariate regression analyses were used to assess the association of tumor type with preoperative seizures.

RESULTS

Data were retrospectively analyzed for 348 consecutive patients who underwent surgical treatment of brain metastases between 1998 and 2019. The cohort had a mean age of 60 years at the time of surgery and was 59% female. The mean and median follow-up durations after the date of surgery for the cohort were 22 months and 10.8 months, respectively. In univariate analysis, frontal lobe location (p = 0.05), melanoma (p = 0.02), KRAS mutation in lung carcinoma (p = 0.04), intratumoral hemorrhage (p = 0.04), and prior radiotherapy (p = 0.04) were associated with seizure presentation. Postoperative checkpoint inhibitor use (p = 0.002), prior radiotherapy (p = 0.05), older age (p = 0.002), distant CNS progression (p = 0.004), and parietal lobe tumor location (p = 0.002) were associated with seizures at 6 months postoperatively. The final multivariate model confirmed the independent effects of tumor location in the frontal lobe and presence of intratumoral hemorrhage as predictors of preoperative seizures, and checkpoint inhibitor use and parietal lobe location were identified as significant predictors of seizures at 6 months postoperatively.

CONCLUSIONS

Within this surgical cohort of patients with brain metastases, seizures were seen in almost a quarter of patients preoperatively. Frontal lobe metastases and hemorrhagic tumors were associated with higher risk of preoperative seizures, whereas checkpoint inhibitor use and parietal lobe tumors appeared to be associated with seizures at 6 months postoperatively. Future research should focus on the effect of metastatic lesion-targeting therapeutic interventions on seizure control in these patients.

BIOM-02. MUTATIONAL ANALYSIS AND SINGLE CELL SEQUENCING OF MELANOMA BRAIN METASTASES REVEALS BRAF STATUS CORRELATES WITH CLINICAL OUTCOME AND DIFFERENTIAL IMMUNE POPULATIONS

Understanding the molecular landscape and microenvironment of melanoma brain metastases is critical to devise improved treatments. Here, we perform bulk and single cell genomic analysis of melanoma brain metastases to identify molecular correlates of clinical outcome. 84 consecutive patients who underwent surgical resection at a single institution with a histo-pathologically confirmed diagnosis of melanoma brain metastasis were retrospectively identified. In 60 patients (71%) with sufficient brain metastasis tissue for targeted next generation sequencing, DNA mutations were assessed with a CLIA certified sequencing assay. Single nuclear RNA sequencing using the 10x platform was performed on n=6 samples from treatment naïve patients. Overall survival (OS) and CNS progression free survival (CNS PFS) from time of brain metastasis diagnosis were estimated using the Kaplan-Meier method. The median patient age was 62 years old (range: 25-78 years), and the median clinical follow up was 17 months. A total of 33 patients (39%) had BRAFV600E melanoma brain metastases. Multivariate analysis incorporating age, performance status, and extracranial disease revealed BRAF status was an independent prognostic factor for OS (p&lt; 0.05). In patients undergoing targeted next generation sequencing, the most common pathogenic variant was TERT promoter mutation (n=44; 73%). With regard to TCGA molecular melanoma subgroups, NRAS mutant (n=22; 37%) brain metastases were most common followed by BRAF mutant (n=20; 33%), NF1 mutant (n=11; 18%), and triple wildtype (n=7; 12%). Evaluation of clinical outcomes in the context of next generation sequencing results revealed no differences by TERT status but demonstrated worse overall survival in the BRAF mutant molecular group (p&lt; 0.01, log-rank test). Single nuclear sequencing of 36,115 nuclei across 6 samples revealed BRAF wildtype tumors exhibit greater infiltrating immune cell populations including microglia and T cell subtypes. Future work will require integration of these findings with different systemic therapy regimens and across larger, prospective, multi-institutional cohorts.

SURG-04. CDK2NA/B, SMAD4, AND PIK3R1 MUTATIONS ARE ASSOCIATED WITH INCREASED RISK OF LOCAL RECURRENCE AFTER SURGICAL RESECTION OF BRAIN METASTASES

BACKGROUND

While resection of brain metastases (BMs) offers favorable local disease control, factors and genetic alterations associated with local recurrence are not well defined. This study examined patient, tumor, treatment, and genetic factors associated with local recurrence.

METHODS

A retrospective, single-center study was conducted with patients who underwent resection of a BM with available clinical outcome and genetic data available. Local recurrence was the primary outcome of the study. Next-generation sequencing of coding regions in over 500 cancer genes was performed to detect mutations. Cox proportional hazards analysis was performed to identify patient, tumor, treatment, and genetic factors associated with local recurrence.

RESULTS

We identified 91 patients who underwent surgical resection of a BM with available data, of which 80 (87.1%) underwent preoperative radiotherapy or received some form of adjuvant radiation to the resection cavity. Primary pathologies in the cohort included non-small cell lung cancer (24.2%), melanoma (24.2%), breast cancer (16.5%), gastrointestinal cancers (13.2%), gynecologic cancers (4.4%), renal cell carcinoma (4.4%), and other cancers (13.2%). Eleven patients (12.1%) developed postoperative recurrence at the surgical site with 6- and 12-month PFS of 91.2% and 84.2%. Multivariate Cox proportional hazard analysis identified cancer type (Gyn and RCC vs Others: OR 39.4, p=0.002), CDK2NA/B co-deletion (OR 37.52, p=0.0009), PIK3R1 mutation (OR 56.88, p=0.003), and SMAD4 mutation (OR 134.8, p=0.0007) to be associated with time to local recurrence. Overall survival and length of follow-up were not different based on mutational status of these genes, demonstrating that results were not due to survival bias.

CONCLUSIONS

Genetic alterations within BMs impact clinical outcomes after surgical resection. Further work is needed to determine if targeted therapies for BMs with these alterations can decrease rates of local recurrence.

SURG-05. SUPERVISED MACHINE LEARNING IDENTIFIES RISK FACTORS ASSOCIATED WITH LEPTOMENINGEAL DISEASE AFTER SURGICAL RESECTION OF BRAIN METASTASES

INTRODUCTION

Predictors of postoperative leptomeningeal disease (LMD) after resection of brain metastases (BMs) are not well defined.

OBJECTIVE

This study examined rates and predictors of LMD, including subtypes, in patients who underwent resection of a BM followed by postoperative radiation.Method: A retrospective, single-center study was conducted examining overall LMD, classical LMD (cLMD), and nodular LMD (nLMD) risk. Logistic regression and a Cox proportional hazards analyses were performed to identify risk factors associated with LMD. Random forest models were constructed to predict LMD and differentiate cLMD versus nLMD. Accuracy and the area under the receiver operating characteristic curve (AUROC) were calculated to evaluate the models.Result: Of the 217 patients in the cohort, 47 (21.7%) developed postoperative LMD with 19(8.8%) cLMD cases and 28(12.9%) nLMD cases . Six-, 12-, and 24-month LMD-free survival rates were 92.3%, 85.6%, and 71.4%, respectively. Patients with cLMD had worse survival outcomes from LMD diagnosis compared to nLMD (2.4 vs 6.9 mo, Log-rank p=0.02), and treatment of LMD was associated with improved survival for both cLMD and nLMD subtypes. Multivariate Cox hazard analysis identified cerebellar/insular/occipital location (HR 3.25, 95% CI 1.73-6.11, p=0.0003), absence of extracranial disease (HR 2.49, 95% CI 1.27-4.88, p=0.008), and ventricle contact (HR 2.82, 95% CI 1.5-5.3, p=0.001) to be associated with postoperative LMD. A predictive model using random forest analysis with an AUROC of 0.87 in a test cohort identified tumor location, systemic disease status, and tumor volume as the most important factors associated with LMD. Both regression analysis and random forest analysis identified postoperative systemic therapy exposure as the main factor differentiating cLMD from nLMD development.

CONCLUSION

Tumor location, absence of extracranial disease at the time of surgery, contact with a ventricle, and increased tumor volume are associated with LMD. Classical LMD is associated with worse prognosis compared to nLMD.

QOL-10. NOVEL MULTIMODAL STUDY OF THREE COGNITIVE REHABILITATION INTERVENTIONS IN LOWER GRADE GLIOMA

BACKGROUND

Grade 2 and 3 glioma survivors (LrGG) are living longer, yet experience cognitive impairments with diminished quality of life (QOL). We present a novel multimodal study of three cognitive rehabilitation interventions in stable LrGG survivors.

METHODS

Participants were radiologically stable adult LrGG patients who were off medical treatment for ≥ 6 months with subjective and objective cognitive impairments ( &gt;1SD in 2 or more domains). Patients were offered either In-person cognitive rehabilitation (strategy training including telehealth), or randomized to App-based cognitive rehabilitation (retraining and strategy training) versus Text messaging (strategy training). Intervention duration was 3 months. Neuropsychological testing (with parallel forms) and QOL assessments were conducted at baseline (T1), immediate post intervention (T2), and 6-month follow-up (T3), and analyzed with repeated measures regression or Wilcoxon signed rank tests.

RESULTS

Of the 33 analyzed (enrollment ongoing); 15/17 In-person, 5/8 App-based, and 8/8 Texting completed ≥ 80% or greater of interventions. Demographic and clinical characteristics were similar between cohorts. Median age was 48 years (range 27-63), 58% astrocytoma, 30% oligodendroglioma, 15% other (1 pilocytic astrocytoma, 4 diffuse glioma NOS), and 76% had prior radiotherapy. Rehabilitation interventions showed improvements in auditory working memory (T1-T2 In-person p= 0.02, eta2= 0.32-medium effect), verbal learning (T1-T3 App-based p= .06, eta2= 0.54-large effect; T1-T3 Texting p= .01, eta2= 0.75-large effect), and verbal memory (T1-T3 App-based p= .06, rho=0.31-medium effect).

CONCLUSION

Significant improvements in cognitive impairments were found with medium to large treatment effects within each cohort. Cognitive rehabilitation via In-person and Texting showed strongest feasibility and acceptability. In-person cognitive rehab showed earlier posttreatment improvements whereas treatment effects for App-based and Texting were noted, but took longer to realize gains. These interventions may show promise for addressing cognitive impairments in LrGG survivors and warrant further investigation.

Prospective genomically guided identification of "early/evolving" and "undersampled" IDH-wildtype glioblastoma leads to improved clinical outcomes

BACKGROUND

Genomic profiling studies of diffuse gliomas have led to new improved classification schemes that better predict patient outcomes compared to conventional histomorphology alone. One example is the recognition that patients with IDH-wildtype diffuse astrocytic gliomas demonstrating lower-grade histologic features but genomic and/or epigenomic profile characteristic of glioblastoma typically have poor outcomes similar to patients with histologically diagnosed glioblastoma. Here we sought to determine the clinical impact of prospective genomic profiling for these IDH-wildtype diffuse astrocytic gliomas lacking high-grade histologic features but with molecular profile of glioblastoma.

METHODS

Clinical management and outcomes were analyzed for 38 consecutive adult patients with IDH-wildtype diffuse astrocytic gliomas lacking necrosis or microvascular proliferation on histologic examination that were genomically profiled on a prospective clinical basis revealing criteria for an integrated diagnosis of "diffuse astrocytic glioma, IDH-wildtype, with molecular features of glioblastoma, WHO grade IV" per cIMPACT-NOW criteria.

RESULTS

We identified that this diagnosis consists of two divergent clinical scenarios based on integration of radiologic, histologic, and genomic features that we term "early/evolving" and "undersampled" glioblastoma, IDH-wildtype. We found that prospective genomically guided identification of early/evolving and undersampled IDH-wildtype glioblastoma resulted in more aggressive patient management and improved clinical outcomes compared to a biologically matched historical control patient cohort receiving standard-of-care therapy based on histomorphologic diagnosis alone.

CONCLUSIONS

These results support routine use of genomic and/or epigenomic profiling to accurately classify glial neoplasms, as these assays not only improve diagnostic classification but critically lead to more appropriate patient management that can improve clinical outcomes.

Multiplatform molecular analyses refine classification of gliomas arising in patients with neurofibromatosis type 1

Gliomas arising in the setting of neurofibromatosis type 1 (NF1) are heterogeneous, occurring from childhood through adulthood, can be histologically low-grade or high-grade, and follow an indolent or aggressive clinical course. Comprehensive profiling of genetic alterations beyond NF1 inactivation and epigenetic classification of these tumors remain limited. Through next-generation sequencing, copy number analysis, and DNA methylation profiling of gliomas from 47 NF1 patients, we identified 2 molecular subgroups of NF1-associated gliomas. The first harbored biallelic NF1 inactivation only, occurred primarily during childhood, followed a more indolent clinical course, and had a unique epigenetic signature for which we propose the terminology "pilocytic astrocytoma, arising in the setting of NF1". The second subgroup harbored additional oncogenic alterations including CDKN2A homozygous deletion and ATRX mutation, occurred primarily during adulthood, followed a more aggressive clinical course, and was epigenetically diverse, with most tumors aligning with either high-grade astrocytoma with piloid features or various subclasses of IDH-wildtype glioblastoma. Several patients were treated with small molecule MEK inhibitors that resulted in stable disease or tumor regression when used as a single agent, but only in the context of those tumors with NF1 inactivation lacking additional oncogenic alterations. Together, these findings highlight recurrently altered pathways in NF1-associated gliomas and help inform targeted therapeutic strategies for this patient population.

MMAP-10 ADVERSE RADIATION EFFECT AFTER STEREOTACTIC RADIOSURGERY AND IMMUNOTHERAPY/TARGETED THERAPY FOR MELANOMA BRAIN METASTASES

BACKGROUND

Safety of immunotherapy (IO) and targeted therapy (TT) with stereotactic radiosurgery (SRS) in melanoma brain metastases (MBM) treatment remains incompletely understood. We aim to identify whether timing of IO/TT in relation to SRS impacts rates of adverse radiation effect (ARE) in MBM.

METHODS

Retrospective review of patients with MBM treated with SRS and IO/TT within three months prior and one year after SRS, from 2011-2021 at a single institution with at least two months MRI follow-up, identified 108 patients with 939 unique MBM meeting criteria. ARE was confirmed on independent imaging review. Concurrent IO/TT was defined as receiving IO/TT within 4 weeks before or after SRS. Data analysis was performed with the univariate cox proportional hazard model and Kaplan-Meier method.

RESULTS

Median radiographic follow-up from time of SRS was 16months. IO/TT was initiated prior to SRS for 681 (72.5%) metastases and after SRS for 258 (27.5%) metastases. 837 (89.1%) metastases received concurrent IO/TT. Most common IO agents were ipilimumab (n=416), nivolumab (n=448), and pembrolizumab (n=203). Most common TT agents were dabrafenib (n=548), trametinib (n=540), and vemurafenib (n=81). 2-year local progression-free survival (PFS), distant intracranial PFS, and overall survival were 94.1%, 33.3%, and 55.2%, respectively. 55 (5.9%) metastases in 33 (30.6%) patients experienced ARE. Median time to ARE was 5mo (IQR 4-9mo). Of those who experienced ARE, 22 (66.7%) patients were symptomatic and treated with steroids; 12 (36.4%) patients underwent surgical intervention. ARE rates were not impacted by concurrent vs nonconcurrent IO/TT (5.5% vs 4.9%, p=0.34) nor IO/TT initiation pre vs post SRS (6.0% vs 5.4%, p=0.61).

CONCLUSION

IO/TT in conjunction with SRS resulted in low ARE rates as compared to historical controls in the pre-IO/TT era. Timing of IO/TT in relation to SRS may not significantly impact ARE rates in MBM treatment.

MMAP-11 VOLUMETRIC STUDY OF BRAIN METASTASES IN EGFR-POSITIVE NSCLC TREATED WITH OSIMERTINIB WITH OR WITHOUT CNS-DIRECTED RADIATION THERAPY

BACKGROUND

In patients with brain metastases (BM) from EGFR-positive non-small cell lung cancer (NSCLC), recent data indicated that treating with CNS-penetrant tyrosine kinase inhibitors such as osimertinib may enable deferring radiotherapy (RT) in select patients. The purpose of this study was to describe the radiographic response of newly diagnosed BM to osimertinib with or without stereotactic radiosurgery or whole brain radiotherapy, to identify parameters that may guide early versus delayed salvage RT.

METHODS

In this single-institution retrospective study, 35 patients with 186 newly diagnosed BM started on osimertinib between 2014 and 2020 were reviewed. BM with tumor volume ≥ 0.1 cm³ were included in the volumetric analyses (N=106 BM). Survival was estimated with the Kaplan-Meier method, and univariable analysis was performed using log-rank tests. Cox proportional hazards was used for multivariable analyses for local control (LC), distant brain failure (DBF), and overall survival (OS).

RESULTS

Of the 35 patients, 8 (23%) received osimertinib alone. Median follow-up was 29 months. The 1- and 2-year LC rates were 94% and 86%. The 1- and 2-year OS rates were 89% and 66%. Median time to DBF was 24 months. Patients treated with osimertinib and RT were more likely to have a significant radiographic volumetric response at early follow-up (4-12 weeks after treatment initiation) compared to osimertinib alone (median volumetric response of –80% vs. –41%, p=0.05). On per lesion analysis, early volumetric response of ≥ 80% was associated with improved LC (3-year LC 98% vs 72%, p=0.04).

CONCLUSIONS

The combination of osimertinib and CNS RT is associated with greater early volumetric response in patients with BM from EGFR-positive NSCLC compared to osimertinib alone. BM with significant initial radiographic response remain well-controlled in the long term. Patients whose BM demonstrate limited initial volumetric response may benefit from targeted RT to provide long term control.

LOCL-06 SUPERVISED MACHINE LEARNING IDENTIFIES RISK FACTORS ASSOCIATED WITH LEPTOMENINGEAL DISEASE AFTER SURGICAL RESECTION OF BRAIN METASTASES

BACKGROUND

Resection of brain metastases (BMs) can help with local disease control, yet predictors of leptomeningeal disease (LMD) after surgery are not well defined. This study examined rates and predictors of LMD in patients who underwent resection of a BM.

METHODS

A retrospective, single-center study was conducted examining LMD risk for adult patients with a BM that underwent resection with postoperative adjuvant radiation. Logistic regression analyses and a supervised machine learning algorithm (Random forest) were implemented to identify factors within the cohort that were associated with LMD.

RESULTS

Of the 182 patients in the cohort, 43 patients (23.6%) developed LMD in the postoperative setting with 18 cases of classical LMD (9.9%) and 25 cases of nodular LMD (13.7%). Median censored time to LMD was not reached, and 6-, 12-, and 24-month LMD-free rates from surgery were 93%, 86.3%, and 71.8%, respectively. Median time from surgery to classical and nodular LMD were 13.1 and 9.5 months, respectively (Log-rank p=0.71). Patients diagnosed with classical LMD had worse survival outcomes from LMD diagnosis compared to nodular LMD (2.6 vs 9.7 mo, Log-rank p=0.02), and LMD-subtype was significantly associated with overall survival from the date of surgery (classical vs nodular vs none: 16.1 vs 20 vs 36.7 mo, p <.0001). Random forest analysis identified primary cancer type, absence of extracranial disease, and tumor volume as the top 3 factors associated with LMD. On multivariate regression analysis, absence of extracranial disease at index surgery was associated with any LMD (OR 2.65, 95% CI 1.15-6.10, p=0.02). Treatment with postoperative checkpoint inhibitors, type of radiation, and performing additional craniotomies were not associated with risk of LMD.

CONCLUSIONS

Classical-type LMD is associated with worse prognosis compared to nodular-type LMD. Absence of extracranial disease at the time of surgery was the most consistent factor associated with LMD on follow-up.

Cellular architecture of human brain metastases

Brain metastasis (BrM) is the most common form of brain cancer, characterized by neurologic disability and an abysmal prognosis. Unfortunately, our understanding of the biology underlying human BrMs remains rudimentary. Here, we present an integrative analysis of >100,000 malignant and non-malignant cells from 15 human parenchymal BrMs, generated by single-cell transcriptomics, mass cytometry, and complemented with mouse model- and in silico approaches. We interrogated the composition of BrM niches, molecularly defined the blood-tumor interface, and revealed stromal immunosuppressive states enriched with infiltrated T cells and macrophages. Specific single-cell interrogation of metastatic tumor cells provides a framework of 8 functional cell programs that coexist or anticorrelate. Collectively, these programs delineate two functional BrM archetypes, one proliferative and the other inflammatory, that are evidently shaped through tumor-immune interactions. Our resource provides a foundation to understand the molecular basis of BrM in patients with tumor cell-intrinsic and host environmental traits.

CTNI-55. THE CDK4/6 INHIBITOR ABEMACICLIB IN PATIENTS WITH RECURRENT MENINGIOMA AND OTHER PRIMARY CNS TUMORS

BACKGROUND

Medical therapies for recurrent brain tumors are limited. Abemaciclib is a small molecule CDK4/6 inhibitor that has demonstrated antitumor activity in multiple cancer types and crosses the blood-brain barrier.

METHODS

We conducted a phase II trial of single-agent abemaciclib in patients with recurrent primary brain tumors utilizing a novel CNS basket trial design with multiple tumor types accrued to separate cohorts including patients with recurrent IDH-wildtype gliomas (Cohort A), any recurrent gliomas requiring cytoreductive surgery (Cohort B), and any other recurrent primary brain tumors (Cohort C) including IDH-mutant gliomas, meningiomas, and other tumor types. In all patients, abemaciclib was administered orally at 200mg twice daily for each 28-day cycle. In cohort B abemaciclib was administered 4-7 days prior to surgery then resumed after recovery. Neuroimaging disease assessments were performed every two cycles. Cohorts were individually assessed for efficacy, tumoral molecular characteristics, and exploratory biomarker analyses. Next generation sequencing was performed on patients who had prior surgery.

RESULTS

To date, a total of 61 patients have enrolled and initiated treatment with abemaciclib. Cohort A enrolled 9 patients with IDH-wildtype WHO grade II and III astrocytomas. Cohort B enrolled 10 patients with astrocytomas of varying IDH-status. Cohort C is a diverse group of 42 patients including 22 treatment-refractory meningiomas, 10 IDH-mutant gliomas (5 astrocytomas, 5 oligodendrogliomas), 3 ependymomas, 3 primary CNS lymphomas, 2 pituitary tumors, 1 glioneuronal rosette forming tumor, and 1 diffuse midline glioma. A total of 7 grade 3 toxicities occurred in 6 patients: fatigue (3), neutropenia (2), colitis (1) and seizure (1); no grade 4 toxicities occurred.

CONCLUSIONS

We present the results of a novel CNS basket trial looking at the efficacy of abemaciclib across multiple recurrent primary brain tumors. Efficacy results will be presented, highlighting an update on promising results in the 22 patients with recurrent meningiomas.

QOLP-32. EFFECT OF CANNABIS USE ON QUALITY OF LIFE AMONG GLIOMA PATIENTS: A LONGITUDINAL PERSPECTIVE

BACKGROUND

Gliomas are devastating primary tumors of the central nervous system that often present with difficult to manage symptoms in addition to the antineoplastic tumor itself. Due to recent increase in popularity and societal acceptance of cannabis products, their use by glioma patients has increased.

METHODS

We conducted a single center, prospective study: patients with glioma answered a locally validated survey to inquire about their cannabis use at baseline and every three months. Quality of Life was measured using the EORTC QLQ-C30, its complementary module BN-20 and the EQ-5D-5L instrument. Eligible participants were classified as cannabis users or non-users. We performed linear regression clustered by subjects to see differences by user group and trends overtime.

RESULTS

To date, 89 patients agreed to participate, enrolled, and answered the baseline questionnaires, and 64 have answered the 3 month follow up survey. The mean age was 49.7(SD 13.74), 55 were male, 55 were cannabis users at baseline (61.8%) and 34 at 3 months (53.13%). Patients who were cannabis users scored 11.73 lower points at baseline when compared to non-users (79.65 [SD 18.93] vs 67.92 [SD 19.22]) in the QLQ-C30 instrument. Similarly, cannabis users recorded 9.624 lower points at 3 months compared to non-users (70.1 [SD 21.33] vs 79.72 [SD13.95]). The difference-in-difference estimator was 2.108 (p&lt; 0.7).

CONCLUSION

Although we observed cannabis users scoring lower QoL measurements (p&lt; 0.05) at baseline and 3 months, we observed a slight improvement in QoL of cannabis users while observing no change or decline (in some measures) among non-users. Our findings provide insight to the impact that cannabis has in QoL over time. While not conclusive, these preliminary results need to be studied on a longer-term basis with a larger sample size in order to detect trends on quality of life among patients with different tumor types.

Salvage Surgery for Local Control of Brain Metastases After Previous Stereotactic Radiosurgery: A Single-Center Series

BACKGROUND

Although overall survival (OS) has improved in patients with brain metastases (BMs), control of recurrent BMs remains a therapeutic challenge. Salvage surgery may achieve acceptable control rates in the setting of progression after previous stereotactic radiosurgery (SRS), yet it remains a question how additional adjuvant therapies may affect outcomes and how patient selection for salvage surgery may be optimized.

METHODS

Patients receiving salvage surgery for BM progression after previous SRS were retrospectively reviewed from a single center. Outcomes of interest included local tumor progression, leptomeningeal dissemination, and OS. Cox proportional hazard models and nominal logistic regression were applied to determine factors associated with outcomes of interest.

RESULTS

A total of 43 patients with 50 BMs were included. After salvage surgery, local progression was observed for 17 BMs (34%), leptomeningeal dissemination was observed in 17 patients (39.5%), and censored median OS was 17.9 months. On multivariate analysis, use of brachytherapy was associated with improved local control (hazard ratio [HR], 0.15; 95% confidence interval [CI], 0.04-0.6; P = 0.008). For patients treated with SRS ≥4.5 months before salvage surgery, both brachytherapy (HR, 0.07; 95% CI, 0.01-0.39; P = 0.002) and postoperative adjuvant SRS (HR, 0.14; 95% CI, 0.02-1.00; P = 0.05) were associated with improved local control compared with no adjuvant radiation therapy. Presence of extracranial malignancy (HR, 6.70; 95% CI, 2.58-17.42; P < 0.0001) was associated with shorter survival. Graded prognostic assessment underestimated survival in 79.1% of patients, with a mean difference of 18.9 months between graded prognostic assessment-estimated and actual OS.

CONCLUSIONS

In properly selected patients, salvage surgery may be an appropriate therapy for BM progression after previous SRS. Adjuvant brachytherapy and repeat SRS can offer significant benefit for local control with salvage resection.

CTNI-47. PHASE II STUDY OF ABEMACICLIB IN RECURRENT GBM PATIENTS WITH CDKN2A/B LOSS AND INTACT RB

Deregulation of the cyclin-dependent kinases (CDK) 4 and 6 (cdk4/6)–cyclin D-INK4—retinoblastoma protein (Rb) signaling pathway is among the most common aberrations found in glioblastoma (GBM) with more than 80% of patients estimated to be affected. We conducted an open label, multi-center, phase II trial of abemaciclib in participants with recurrent glioblastoma (GBM) at their first relapse and with documented evidence of CDKN2A/B loss and intact RB from archival tissue. A total of 32 patients enrolled on the non-surgical arm of the study with 13 women (40.63%) and median KPS 90 [range 60–100]. The PFS6 rate was 9.37% [95% CI, 2.4%, 22.27%], median PFS 55 days [95% CI, 49, 56], and median OS 384 days [95% CI, 228, 488]. Out of 31 evaluable patients, best response was PR 1 (3.2%), SD 11 (35.5%), and PD 19 (61.3%). The most common grade 3 or higher toxicities at least possibly related to abemaciclib included leukopenia (21.9%), neutropenia (18.6%), lymphopenia (9.4%), and thrombocytopenia (6.3%). Abemaciclib has minimal activity in this preselected recurrent GBM population. Correlative studies from the surgical arm of this study are pending.

CTIM-15. PRELIMINARY RESULTS OF A PHASE II STUDY OF NIVOLUMAB WITH HYPOFRACTIONATED RE-RADIATION AND BEVACIZUMAB FOR RECURRENT MGMT METHYLATED GLIOBLASTOMA

Standard of standard of care for glioblastoma (GBM) remains unsatisfactory with universal disease recurrence and a median survival of &lt; 2 years. Immune checkpoint inhibitors (ICI) have shown limited single-agent activity in GBM thus far. GBMs with methylated MGMT promoter and no baseline corticosteroid dependence may be most likely to derive benefit from ICI. The combination of ICIs with radiation has shown promising activity in other human cancers. Combining nivolumab and re-RT/bevacizumab in GBM may augment ICI activity through immunogenic effects of radiation, may reduce the risk of radiation necrosis by addition of bevacizumab at the time of radiation, and may reduce the need for corticosteroids. In this multicenter phase II study, nivolumab is combined with re-irradiation and optional concurrent bevacizumab followed by nivolumab in patients with first recurrence of IDH-wildtype and MGMT methylated glioblastoma. Primary objective is to improve 1-year overall survival (OS) from 33 (based on EORTC 26101) to 50%. Nine-three patients are required to show a significant finding with an α of 0.05 and 81% power. Thirteen of 93 patient (14%) have been enrolled with a median age of 59 (range 42–71) with a median KPS of 90 (range 70–90). Treatment has been tolerated well without any grade ≥ 4 toxicities and only one grade 3 (amylase elevation). The most common adverse events were pruritus and hypothyroidism in 3/13 (23%). The median progression-free survival (PFS) is 7 months with a 6months PFS of 55.6%. The 12months OS is 66.7%. Patients with recurrent MGMT methylated, IDH-wildtype glioblastoma tolerate trial treatment with acceptable toxicities. Clinical efficacy in the first patients enrolled shows a promising effect. Enrollment is ongoing.

Frequency and outcomes of brain metastases in patients with HER2-mutant lung cancers

BACKGROUND

Mutations in human epidermal growth factor receptor 2 (HER2; also known as ERBB2) are found in approximately 2% of lung adenocarcinomas. The frequency and clinical course of brain metastases in this oncogenic subset are ill defined.

METHODS

Baseline and subsequent development of brain metastases was evaluated in consecutive patients with HER2-mutant (n = 98), epidermal growth factor receptor (EGFR)-mutant (n = 200), and KRAS-mutant lung cancers (n = 200).

RESULTS

At metastatic diagnosis, the odds ratio (ORs) for brain metastases was similar for patients whose tumors harbored HER2 mutations (19%) in comparison with patients with KRAS mutations (24%; OR for HER2 vs KRAS, 0.7; P = .33) but lower compared to patients with EGFR mutations (31%; OR for HER2 vs EGFR, 0.5; P = .03). Patients with lung cancer and HER2 mutations developed more brain metastases on treatment than patients with KRAS mutations (28% vs 8%; hazard ratio [HR], 5.2; P < .001) and trended more than patients with EGFR mutations (28% vs 16%; HR, 1.7; P = .06). Patients with HER2 YVMA mutations also developed more brain metastases on treatment than patients with KRAS mutations (HR, 5.9; P < .001). The median overall survival (OS) was shorter for patients with HER2-mutant (1.6 years; P < .001) or KRAS-mutant lung cancers (1.1 years; P < .001) than patients with EGFR-mutant lung cancers (3.0 years). Brain metastases occurred in 47% of patients with HER2-mutant lung cancers, which imparted shorter OS (HR, 2.7; P < .001).

CONCLUSIONS

These data provide a framework for brain imaging surveillance in patients with HER2-mutant lung cancers and underpin the need to develop HER2-targeted agents with central nervous system activity.

Genomic Correlates of Disease Progression and Treatment Response in Prospectively Characterized Gliomas

PURPOSE

The genomic landscape of gliomas has been characterized and now contributes to disease classification, yet the relationship between molecular profile and disease progression and treatment response remain poorly understood.Experimental Design: We integrated prospective clinical sequencing of 1,004 primary and recurrent tumors from 923 glioma patients with clinical and treatment phenotypes.

RESULTS

Thirteen percent of glioma patients harbored a pathogenic germline variant, including a subset associated with heritable genetic syndromes and variants mediating DNA repair dysfunctions (29% of the total) that were associated with somatic biallelic inactivation and mechanism-specific somatic phenotypes. In astrocytomas, genomic alterations in effectors of cell-cycle progression correlated with aggressive disease independent of IDH mutation status, arose preferentially in enhancing tumors (44% vs. 8%, P < 0.001), were associated with rapid disease progression following tumor recurrence (HR = 2.6, P = 0.02), and likely preceded the acquisition of alkylating therapy-associated somatic hypermutation. Thirty-two percent of patients harbored a potentially therapeutically actionable lesion, of whom 11% received targeted therapies. In BRAF-mutant gliomas, response to agents targeting the RAF/MEK/ERK signaling axis was influenced by the type of mutation, its clonality, and its cellular and genomic context.

CONCLUSIONS

These data reveal genomic correlates of disease progression and treatment response in diverse types of glioma and highlight the potential utility of incorporating genomic information into the clinical decision-making for patients with glioma.

Sequencing and curation strategies for identifying candidate glioblastoma treatments

Background

Prompted by the revolution in high-throughput sequencing and its potential impact for treating cancer patients, we initiated a clinical research study to compare the ability of different sequencing assays and analysis methods to analyze glioblastoma tumors and generate real-time potential treatment options for physicians.

Methods

A consortium of seven institutions in New York City enrolled 30 patients with glioblastoma and performed tumor whole genome sequencing (WGS) and RNA sequencing (RNA-seq; collectively WGS/RNA-seq); 20 of these patients were also analyzed with independent targeted panel sequencing. We also compared results of expert manual annotations with those from an automated annotation system, Watson Genomic Analysis (WGA), to assess the reliability and time required to identify potentially relevant pharmacologic interventions.

Results

WGS/RNAseq identified more potentially actionable clinical results than targeted panels in 90% of cases, with an average of 16-fold more unique potentially actionable variants identified per individual; 84 clinically actionable calls were made using WGS/RNA-seq that were not identified by panels. Expert annotation and WGA had good agreement on identifying variants [mean sensitivity = 0.71, SD = 0.18 and positive predictive value (PPV) = 0.80, SD = 0.20] and drug targets when the same variants were called (mean sensitivity = 0.74, SD = 0.34 and PPV = 0.79, SD = 0.23) across patients. Clinicians used the information to modify their treatment plan 10% of the time.

Conclusion

These results present the first comprehensive comparison of technical and machine augmented analysis of targeted panel and WGS/RNA-seq to identify potential cancer treatments.

Clinical presentation, treatment, and outcomes of patients with central nervous system involvement in extranodal natural killer/T-cell lymphoma

Extranodal natural killer (NK)/T-cell lymphoma (ENKTCL) is a rare type of Non-Hodgkin's lymphoma which rarely metastasizes to the central nervous system (CNS). Ten of 60 patients (16.7%) with ENKTCL followed at Memorial Sloan Kettering Cancer Center (MSKCC) were diagnosed with CNS involvement between 1995 and 2016. Eight patients had systemic disease at the time of CNS diagnosis; one patient never developed systemic disease and another was in remission at the time of CNS relapse. Median overall survival was 3.8 months; at time of this report 9 patients have died and one who underwent autologous stem cell transplant (ASCT) is alive 27 months after CNS diagnosis. Five patients achieved a complete response in the CNS; one is still alive, one died of systemic disease, and three died of infection. CNS ENKTCL portends a grim prognosis, with no standard treatment. Prospective study on ASCT and immunotherapy in CNS ENKTCL is warranted.

Patients’ education about a new service available at Memorial Sloan Kettering Multidisciplinary Clinic for frail patients with central nervous system cancers

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Background: A multidisciplinary clinic (MDC) is a pilot project in the MSK Department of Neurology designed to improve quality of care and patient satisfaction. The MDC enables the patient to receive coordinated care from multiple providers (eg a physical therapist, physiatrist, nutritionist, social worker, case manager, spiritual advisor, and neurologist) in one location in one longer visit. This approach is new, and few patients (pts) have had the opportunity to experience the MDC. We hypothesized that giving the patient information about the MDC will increase the MDC volume. Methods: This is a prospective quality improvement study from June 14, 2018 to July 20, 2018 conducted in four Neuro-Oncology clinics. Pts with primary or metastatic central nervous system (CNS) cancers were identified prior to the visits in their regular oncology clinic. Pts were asked if they were interested in receiving verbal or written information (brochure) about the MDC. For each patient, we recorded if they agreed to receive information, what information they received, and whether they scheduled an appointment at the MDC. We also recorded patient demographics, CNS cancer type, and whether they were accompanied by caregivers. Results: We approached 41 pts. Of the 41 pts, 31(74%) were accompanied by caregivers. Median patient age was 58 (range, 24-79) years. 26 (62%) were female. CNS cancers were primary brain tumors in 31 (76%) and brain metastases in 10 (24%). 27 (64%) of 41 pts agreed to receive both verbal information and a brochure. The remaining 14 (36%) pts did not want to receive more information about the MDC; of these, one patient didn’t take a brochure, 2 pts resided out of the country, and one patient said all needs had been addressed. Within 4 weeks of this pilot study four (15%) of 27 pts scheduled an appointment in the MDC clinic for upcoming dates. Conclusions: Among our pts with CNS tumors visiting their oncologists, 64% were willing to receive information about the MDC, four (15%) made an appointment with the MDC. More study is needed to facilitate education about and access to the MDC; to identify potential barriers; and to obtain longer follow-up.

Multicenter Phase IB Trial of Carboxyamidotriazole Orotate and Temozolomide for Recurrent and Newly Diagnosed Glioblastoma and Other Anaplastic Gliomas

Purpose Carboxyamidotriazole orotate (CTO) is a novel oral inhibitor of non-voltage-dependent calcium channels with modulatory effects in multiple cell-signaling pathways and synergistic effects with temozolomide (TMZ) in glioblastoma (GBM) models. We conducted a phase IB study combining CTO with two standard TMZ schedules in GBM. Methods In cohort 1, patients with recurrent anaplastic gliomas or GBM received escalating doses of CTO (219 to 812.5 mg/m² once daily or 600 mg fixed once-daily dose) combined with TMZ (150 mg/m² 5 days during each 28-day cycle). In cohort 2, patients with newly diagnosed GBM received escalating doses of CTO (219 to 481 mg/m²/d once daily) with radiotherapy and TMZ 75 mg/m²/d, followed by TMZ 150 mg to 200 mg/m² 5 days during each 28-day cycle. Results Forty-seven patients were enrolled. Treatment was well tolerated; toxicities included fatigue, constipation, nausea, and hypophosphatemia. Pharmacokinetics showed that CTO did not alter TMZ levels; therapeutic concentrations were achieved in tumor and brain. No dose-limiting toxicities were observed; the recommended phase II dose was 600 mg/d flat dose. Signals of activity in cohort 1 (n = 27) included partial (n = 6) and complete (n = 1) response, including in O⁶-methylguanine-DNA methyltransferase unmethylated and bevacizumab-refractory tumors. In cohort 2 (n = 15), median progression-free survival was 15 months and median overall survival was not reached (median follow-up, 28 months; 2-year overall survival, 62%). Gene sequencing disclosed a high rate of responses among EGFR-amplified tumors ( P = .005), with mechanisms of acquired resistance possibly involving mutations in mismatch-repair genes and/or downstream components TSC2, NF1, NF2, PTEN, and PIK3CA. Conclusion CTO can be combined safely with TMZ or chemoradiation in GBM and anaplastic gliomas, displaying favorable brain penetration and promising signals of activity in this difficult-to-treat population.

Twice weekly pulse and daily continuous-dose erlotinib as initial treatment for patients with epidermal growth factor receptor-mutant lung cancers and brain metastases

BACKGROUND

In a phase 1 study of pulse/continuous-dose erlotinib, no patient had disease progression in the central nervous system (CNS). This expansion cohort of the phase 1 study tested the same regimen in a cohort of individuals with epidermal growth factor receptor (EGFR)-mutant lung cancers with untreated brain metastases.

METHODS

Patients had not received EGFR tyrosine kinase inhibitors or radiation for brain metastases. All received 1200 mg of erlotinib on days 1 and 2 and 50 mg on days 3 to 7 weekly. The primary endpoints were the overall and CNS response rates (according to version 1.1 of the Response Evaluation Criteria in Solid Tumors).

RESULTS

Between May 2015 and August 2016, 19 patients were enrolled. Forty-two percent of the patients had target brain lesions, and the median size of the target brain lesions was 13 mm. Overall, 14 patients (74%; 95% confidence interval [CI], 51%-89%) had partial responses. The response rate in brain metastases was 75%. The overall median progression-free survival was 10 months (95% CI, 7 months to not reached). Only 3 patients (16%) had CNS progression. To date, 4 patients required CNS radiation at some time during their course. The adverse events (any grade) seen in 10% or more of the patients were rash, diarrhea, nausea, an increase in alanine aminotransferase, and fatigue.

CONCLUSIONS

Pulse/continuous-dose erlotinib produced a 74% overall response rate and a 75% response rate in brain metastases in patients with EGFR-mutant lung cancers and untreated brain metastases. CNS control persisted even after progression elsewhere. Although this regimen did not improve progression-free survival or delay the emergence of EGFR T790M, it prevented progression in the brain and could be useful in situations in which CNS control is critical. Cancer 2018;124:105-9. © 2017 American Cancer Society.

Pulse-continuous dose erlotinib as initial targeted therapy for patients with EGFR-mutant lung cancers with untreated brain metastases

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Background: Clarke (Neurooncol 2010) reported responses with intermittent high pulse doses of erlotinib (leading to higher concentrations in CSF) given to patients with EGFR-mutant central nervous system metastases developing on standard erlotinib doses. In a phase 1 study of pulse-continuous dose erlotinib, no patient developed progression in existing or new brain or leptomeningeal metastases (Yu Ann Oncol 2016). This phase 2 trial tested pulse-continuous dose erlotinib in patients with lung cancers with EGFRmutations with brain metastases. Methods: Patients had no prior EGFR TKI or radiation to the brain and at least 1 target brain metastasis. All received initial daily "pulse" doses of erlotinib 1200 mg days 1&2 and "continuous" 50 mg doses days 3-7 (doses and schedule from the Yu Phase 1 study), weekly until progression. The co-primary endpoints were overall and brain metastasis response by RECIST 1.1. Results: We enrolled 19 patients with EGFR-mutant lung cancers: median age 61yrs (range 45-80), 74% women, 95% Karnofsky PS ≥80%, 1 leptomeningeal disease, 33% prior pemetrexed-based chemotherapy. The median size of target brain metastases was 13 mm (range 10-19 mm). 32% were on dexamethasone for cerebral edema. The partial response rate overall was 74% (95% CI 51-89%) and also 74% in brain metastases. Of 10 patients with progression, 9/10 occurred in non-brain sites (4 EGFRT790M, 1 with progression in brain as well), 1 with leptomeningeal. The median progression free survival was 10 mo (range 7-NR mo). Pulse doses were reduced in 68% (median delivered pulse dose 1050 mg days 1&2, range 600-1200 mg). Incidences of any gradeof rash and diarrhea were 84% and 63% respectively. There were no grade 4 or 5 toxicities. Conclusions: Pulse-continuous dose erlotinib alone controlled brain and leptomeningeal metastases in 89% (95% CI 67-98%) of patients with EGFR-mutant lung cancers with central nervous system spread pretreatment, with an overall response rate of 74% and progression free survival and rates of rash and diarrhea comparable to series with erlotinib 150 mg daily. Supported by Astellas, CA 129243, CA 008748. NCT01967095 Clinical trial information: NCT01967095.

Dynamic contrast-enhanced MRI perfusion for differentiating between melanoma and lung cancer brain metastases

Brain metastases originating from different primary sites overlap in appearance and are difficult to differentiate with conventional MRI. Dynamic contrast-enhanced (DCE)-MRI can assess tumor microvasculature and has demonstrated utility in characterizing primary brain tumors. Our aim was to evaluate the performance of plasma volume (Vp) and volume transfer coefficient (K^trans ) derived from DCE-MRI in distinguishing between melanoma and nonsmall cell lung cancer (NSCLC) brain metastases. Forty-seven NSCLC and 23 melanoma brain metastases were retrospectively assessed with DCE-MRI. Regions of interest were manually drawn around the metastases to calculate Vp_mean and Kmeantrans. The Mann-Whitney U test and receiver operating characteristic analysis (ROC) were performed to compare perfusion parameters between the two groups. The Vp_mean of melanoma brain metastases (4.35, standard deviation [SD] = 1.31) was significantly higher (P = 0.03) than Vp_mean of NSCLC brain metastases (2.27, SD = 0.96). The Kmeantrans values were higher in melanoma brain metastases, but the difference between the two groups was not significant (P = 0.12). Based on ROC analysis, a cut-off value of 3.02 for Vp_mean (area under curve = 0.659 with SD = 0.074) distinguished between melanoma brain metastases and NSCLC brain metastases (P < 0.01) with 72% specificity. Our data show the DCE-MRI parameter Vp_mean can differentiate between melanoma and NSCLC brain metastases. The ability to noninvasively predict tumor histology of brain metastases in patients with multiple malignancies can have important clinical implications.

Bevacizumab in high-grade glioma patients following intraparenchymal hemorrhage

BACKGROUND

Intraparenchymal hemorrhage (IPH) is a relative contraindication to bevacizumab therapy, an anti-vascular endothelial growth factor (VEGF) monoclonal antibody approved for the treatment of recurrent glioblastoma. However, in patients with symptomatic enhancing tumors and poor functional status, bevacizumab may be the only beneficial therapeutic option.

METHODS

We retrospectively reviewed all patients with high-grade glioma who were treated between January 1, 2005 and December 31, 2014 with bevacizumab despite prior IPH.

RESULTS

Eighteen patients met our study criteria. There were 12 women and 6 men with a median age of 56 years. Tumor types were glioblastoma (n = 15), anaplastic astrocytoma (n = 2), and anaplastic oligodendroglioma (n = 1). Seventeen patients had prior spontaneous intratumoral bleed (13 grade 1-2; 4 grade 3-4); the 1 remaining patient had a grade 3 bleed due to cerebral venous thrombosis. Among them, identifiable risk factors for hemorrhage were anti-VEGF therapy, anticoagulation use, thrombocytopenia, and hypertension; seven had no identifiable risk factors. The median duration from IPH to (re-)initiation of bevacizumab was 113 days (range 13-1367). Brain imaging performed prior to bevacizumab treatment showed persistent or evolving hemorrhage in 8 patients and complete resolution in 10 patients. With a median follow-up duration of 137 days after bevacizumab re-initiation, only 1 (6%) of the 18 patients re-bled; this patient had an anaplastic oligodendroglioma and developed a grade 2 intratumoral bleed after 3 doses of bevacizumab.

CONCLUSIONS

The incidence of re-bleed is rare. Bevacizumab use was safe in patients with recurrent high-grade glioma following IPH for whom no other meaningful treatment options existed.