Residual symptoms and long-term outcomes after all-cause autoimmune encephalitis in adults

BACKGROUND AND OBJECTIVES

To evaluate residual symptoms after all-cause autoimmune encephalitis in a real-life outpatient setting and compare long-term outcome measures. A secondary objective was to identify correlates of poor outcomes.

METHODS

We analyzed patients referred to the Neuroimmunology clinic for evaluation of autoimmune encephalitis for whom standardized data were collected. We compared the prevalence of symptoms at the latest follow-up to presentation and calculated symptom improvement rates. We compared the Modified Rankin Scale (mRS) to the Clinical Assessment Scale for Autoimmune Encephalitis (CASE). Non-parametric Wilcoxon rank sum tests and Fisher's exact tests were used to compare clinical attributes between patients with and without poor outcomes.

RESULTS

We evaluated 54 patients from 2017 to 2021 of whom 33 met inclusion criteria (average age 47±20 years, 57% females, 55% seropositive). By latest follow-up, 94% improved compared to presentation but six patients (18%) had poor outcomes as defined by an mRS ≥3. The most common residual symptoms were cognitive and mood dysfunction. The highest improvement rates were in alertness and psychosis while the lowest were in motor function and ataxia. CASE had moderate correlation with mRS (r2 = 0.53 [95%CI:0.23,0.74, p = 0.0015) but it captured more nuances than mRS at both presentation and follow-up. Older age and higher post-treatment CASE score correlated with poor outcomes.

DISCUSSION

Most autoimmune encephalitis patients experience symptom improvement post-treatment. The CASE score was more representative of the wide symptomatic spectrum of autoimmune encephalitis and correlated with poor outcomes. However, CASE did not capture patients with dysautonomia, sleep dysfunction, or death.

CTIM-18. LUMINOS-101: INITIAL SAFETY AND TOLERABILITY OF PVSRIPO AND PEMBROLIZUMAB COMBINATION THERAPY IN RECURRENT GLIOBLASTOMA

BACKGROUND

Recurrent glioblastoma (rGBM) is rapidly fatal with current therapies. PVSRIPO is an intratumoral immunotherapy targeting CD155 on antigen-presenting and malignant cells of solid tumors. Preclinically, PVSRIPO treatment leads to systemic, tumor antigen-specific, polyfunctional T-cell–mediated anti-tumor response, predominately driven by type I/III interferons. This inflammatory signature generates anti-tumor immunity and upregulates the programmed death (PD)-1 immune checkpoint in the tumor microenvironment. Preclinical models (including GBM) have shown that PVSRIPO+anti-PD-1/L1 therapy was more efficacious than either agent alone, warranting further investigation.

METHODS

Adults with histologically confirmed rGBM (1-2 prior progressions), Karnofsky performance status (KPS) ≥70, and an active, supratentorial, contrast-enhancing lesion (1-5.5 cm), received PVSRIPO (5x107 TCID50) intratumorally via convection-enhanced delivery (Day 1), followed by 200 mg pembrolizumab IV at week 2, given every 3 weeks for up to 24 months, to evaluate the safety/efficacy of the combination. A safety lead-in period (n=3-6) with a minimum 21–28-day delay before treatment of subsequent patients was planned, with a data safety monitoring board (DSMB) evaluating safety/tolerability prior to expansion (up to N=30).

RESULTS

The first 3 patients enrolled (ages 55-60, KPS 90-100) all received PVSRIPO followed by pembrolizumab (1-5 cycles), as planned. At cutoff (26-106 days of follow-up), there were no dose-limiting toxicities, treatment-emergent (TE) serious adverse events (SAE), or TEAEs necessitating a delay in initial/subsequent pembrolizumab treatments. All patients experienced a related TEAE, all grade 1 or 2 in severity. One patient experienced an AE of special interest (peritumoral edema, resulting in headache and hemiparesis), successfully managed with low-dose bevacizumab and corticosteroids. The DSMB unanimously recommended the study proceed without modification.

CONCLUSIONS

Intratumoral PVSRIPO+pembrolizumab was reasonably well tolerated, warranting continued investigation of the safety and efficacy of this combination in patients with rGBM.

IMMU-02. PHASE I/II STUDY OF LASER INTERSTITIAL THERMOTHERAPY (LITT) COMBINED WITH CHECKPOINT INHIBITOR FOR RECURRENT GLIOBLASTOMA (RGBM): PRELIMINARY RESULTS

BACKGROUND

Recurrent glioblastoma (rGBM) has poor response rate and survival. Laser Interstitial Thermotherapy (LITT), a minimally invasive approach, improves survival but is not curative alone. Previous studies of LITT suggested the possibility of an abscopal effect. Indeed, GBM are known to harbor elevated levels of immunosuppressive cells such as Treg, M2 macrophages and MDSC both in the tumor microenvironment as well as in the systemic circulation. Checkpoint inhibition (CPI) immunotherapy has proven highly effective for some solid tumors. CPI in newly diagnosed GBM demonstrated safety in phase I trials (NRG BN-002). Further, preclinical studies targeting PD-1 with concurrent RT appears to be synergistic and improve survival. We hypothesized that LITT would block tumor-induced immunosuppression and introduce tumor neoantigens. However, there was no data regarding safety of pembrolizumab combined with LITT. We thus conducted a phase I/II study of LITT + pembrolizumab starting at three times relative to LITT.

METHODS

This is a three armed Phase I/II study based on timing of pembrolizumab (200 mg q 21 days) relative to LITT at 35d or 14d post-op, or 7d pre-op, with an expansion cohort phase II arm conducted at the earliest tolerated time of CPI administration. Adults with proven supratentorial rGBM with KPS >=70 and <= 2mg/d of dexamethasone were eligible.

RESULTS

Arm 1-2 of the phase I trial demonstrated no SAEs grade II or greater, but limited evidence of response. Arm 3 (neoadjuvant) pembrolizumab appears to be equally safe and has been expanded to phase II, demonstrating at least two CR among the first 3 patients (66.6%) with >= 9 month follow-up and patients remain clinically stable at 10 and 15 months post-op.

CONCLUSIONS

Neoadjuvant pembrolizumab combined with LITT for rGBM appears to be safe in this phase I trial, and demonstrates early evidence of response. The phase II trial is ongoing.

NCOG-33. HEMATOLOGIC PREDICTORS OF OUTCOMES IN GLIOBLASTOMA TREATED WITH SURGERY AND CHEMORADIATION

BACKGROUND

There are conflicting reports regarding the prognostic value of platelet and other blood counts in glioblastoma. However, few series have looked at all hematologic parameters simultaneously.

METHODS

We performed a retrospective chart review of patients diagnosed with supratentorial glioblastoma from 2014-2019 who started conventional chemoradiation following initial surgical biopsy and/or resection. Hematologic parameters were collected at baseline, in the preoperative and postoperative periods and at the initiation and completion of chemoradiation. This included platelet counts, hemoglobin levels, white blood cell counts (WBC), neutrophil and lymphocyte counts with neutrophil:lymphocyte (NLR) and platelet:lymphocyte ratios (PLR) calculated at each time point. Cox regression was performed to assess the association between each hematologic parameter and both overall survival (OS) and progression free survival (PFS). A multivariate Cox proportional hazards model adjusted for all hematologic parameters, age, sex, race and KPS was generated for each time point. All hematologic parameters were modeled as continuous variables.

RESULTS

A total of 58 patients met inclusion criteria. 18 were female and 40 male. The median age was 59.5 (range 43-82). Median follow up for all patients was 15.3 months. A total of 52 patients completed radiation therapy and 18 completed 6 cycles of adjuvant chemotherapy. Hemoglobin and neutrophil counts at the conclusion of chemoradiation were associated with OS and PFS on univariate and multivariate analyses. The HR for OS were 0.74 (95% CI 0.5807-0.9313) and 1.28 (1.143-1.441) respectively. The HR for PFS were 0.70 (0.5531-0.8881) and 1.16 (1.05-1.271) respectively. Postoperative lymphocyte and platelet counts at initiation of chemoradiation were both associated with OS with unadjusted HR of 3.2 (1.037-9.960) and HR of 0.99 (0.9898-0.9999) respectively, which remained significant on multivariate analysis. However, neither were associated with PFS.

CONCLUSION

Several hematologic parameters are associated with glioblastoma outcomes in these initial analyses. Further analyses with additional patients are ongoing.

PATH-30. CLINICAL AND GENETIC CHARACTERISTICS OF HISTONE H3 K27M-MUTANT DIFFUSE MIDLINE GLIOMAS IN ADULTS

BACKGROUND

“Diffuse midline glioma, H3 K27M-mutant” is a new tumor entity established in the 2016 WHO Classification of Tumors of the CNS that comprises a set of diffuse gliomas arising in midline structures that is molecularly defined by a recurrent K27M mutation in genes encoding the histone 3 variants H3.3 or H3.1. While this tumor entity is associated with poor prognosis in children, clinical experience in adults remains limited. Given the more frequent origin in the thalamus or spinal cord in adults versus the brainstem in children, gliomas with this mutation may encompass a heterogeneous population of tumor subtypes that vary based on patient age, anatomic site of origin, and concurrent genetic alterations.

METHODS

The 60 patients included were 18 years or older at initial diagnosis, during the period of 2014-2019 at UCSF. Cases were identified using immunohistochemistry with a H3 K27M-mutant specific antibody and/or next-generation sequencing of histone 3 genes H3F3A, HIST1H3B and HIST1H3C. Targeted NGS was performed on tumors from 21 patients, utilizing an UCSF institutional panel or a variety of commercial sources.

RESULTS

Patients presented primarily in the 3rd decade of life, and 57% of tumors were located in the thalamus. Genomic profiling revealed p.K27M mutations exclusively in H3F3A and an absence of mutations in HIST1H3B or HIST1H3C, which are present in approximately one-third of pediatric diffuse midline gliomas. Additionally, these adult H3 K27M-mutant diffuse midline gliomas are universally IDH-wildtype, and have frequent mutations in TP53, PPM1D, FGFR1, NF1, and ATRX. The overall survival of this adult cohort is longer than historical averages for both H3 K27M-mutant diffuse midline glioma in children and IDH-wildtype glioblastomas in adults.

CONCLUSIONS

Together, these findings indicate that H3 K27M-mutant diffuse midline glioma represents a heterogeneous disease with regard to outcomes, sites of origin, and molecular pathogenesis in children versus adults.

Ependymoma, NOS and anaplastic ependymoma incidence and survival in the United States varies widely by patient and clinical characteristics, 2000-2016

BACKGROUND

Ependymoma is a rare CNS tumor arising from the ependymal lining of the ventricular system. General differences in incidence and survival have been noted but not examined on a comprehensive scale for all ages and by histology. Despite the rarity of ependymomas, morbidity/mortality associated with an ependymoma diagnosis justifies closer examination.

METHODS

Incidence data were obtained from the Central Brain Tumor Registry of the United States in collaboration with the Centers for Disease Control and Prevention and the National Cancer Institute, and survival data from Surveillance Epidemiology and End Results, from 2000 to 2016 for anaplastic ependymoma and ependymoma, not otherwise specified (NOS). Age-adjusted incidence rates (IRs) per 100 000 person-years were analyzed by age, sex, race, and location. Survival analysis was performed with Kaplan-Meier curves and multivariable Cox proportional hazards models.

RESULTS

Incidence of anaplastic ependymoma was highest in ages 0 to 4 years. African American populations had lower incidence but had a 78% increased risk of death compared to white populations (hazard ratio [HR]: 1.78 [95% CI, 1.30-2.44]). Incidence was highest for anaplastic ependymoma in the supratentorial region. Adults (age 40+ years) had almost twice the risk of death compared to children (ages 0-14 years) (HR: 1.97 [95% CI, 1.45-2.66]). For ependymoma, NOS, subtotal resection had a risk of mortality 1.86 times greater than gross total resection ([HR: 1.86 [95% CI, 1.32-2.63]).

CONCLUSIONS

African American populations experienced higher mortality rates despite lower incidence compared to white populations. Extent of resection is an important prognostic factor for survival. This highlights need for further evaluation of treatment patterns and racial disparities in the care of patients with ependymoma subtypes.

Treatment and surgical factors associated with longer-term glioblastoma survival: a National Cancer Database study

Background

Insufficient data exist to characterize factors associated with longer-term survival of glioblastoma (GBM). A population-based analysis of GBM longer-term survivors (LTS) in the United States was conducted to investigate the association between treatment, demographic, surgical factors, and longer-term survival.

Methods

From the National Cancer Database, GBM patients were identified using ICD-O-3 histology codes 9440-9442/3, 2005-2015 and were divided into routine (≤3 years) and longer-term (>3 years) overall survival (OS) groups. Univariable and multivariable logistic regression analysis was used to assess factors associated with longer-term survival. A subset analysis was performed to further investigate the association of extent of resection and treatment combinations on OS outcomes.

Results

A total of 93 036 patients with GBM met study criteria. Among these patients, 8484 were LTS and 84 552 were routine survivors (RS). When comparing LTS (OS of >3 years) with RS (OS of ≤3 years), younger age, insured status, metro/urban residence, treatment at academic facility, and fewer comorbidities were associated with longer-term survival. In addition, trimodality therapy (chemotherapy + radiation + surgery) was associated with having best odds of longer-term survival (odds ratio = 4.89, 95% confidence interval [3.58, 6.68]); 74% of LTS received such therapy compared with 51% of RS. Subset analysis revealed that total resection is only associated with longer-term survival status for those receiving trimodality therapy or surgery only.

Conclusions

In a population-based analysis, standard of care surgery and chemo radiation connote a survival advantage in GBM. Among those receiving standard of care, having a total resection is most beneficial for longer-term survival status.

A systematic review and meta-analysis examining the effects of cannabis and its derivatives in adults with malignant CNS tumors

Background

Primary CNS tumors constitute a heterogeneous group of neoplasms that share a considerable morbidity and mortality rate. To help control tumor growth and clinical outcomes (overall survival, progression-free survival, quality of life) symptoms, patients often resort to alternative therapies, including the use of cannabis. Despite rapidly growing popularity, cannabis and its impact on patients with primary malignant CNS tumors is understudied.

Methods

To shed light on the lack of scientific evidence in this field, in November 2018 we conducted a search and examination of cannabis in neuro-oncology in major journal databases and bibliographies of selected articles, and through abstracts of annual meetings using prespecified criteria in line with the Cochrane Collaboration guidelines.

Results

We identified 45 publications, of which 9 were selected. Five studies were included. Publication dates ranged from 2004 to 2018 and included varying histologies of primary brain tumors. The average survival at 1 year was 56.09% (95% CI: 48.28-63.9). There was no difference in risk ratio (RR) for death at 1 year between groups (RR: 1.069 [95% CI: 0.139-8.25]). We found strong evidence of heterogeneity (Q = 74.0%; P = .021). We found no statistical evidence of publication bias (P = .117; SD = 1.91).

Conclusions

There was limited moderate-quality evidence that supports the use of cannabinoids as adjuvant to the standard of care in the treatment of brain and CNS tumors. There was very low-quality evidence suggesting that cannabinoids were associated with adult-onset gliomas. Further prospective clinical trials are necessary to adequately evaluate the impact of cannabinoids on CNS tumors, specifically on survival and quality of life.

PATH-38. ROSETTE-FORMING GLIONEURONAL TUMOR IS DEFINED BY FGFR1 ACTIVATING ALTERATIONS WITH FREQUENT ACCOMPANYING PI3K AND MAPK PATHWAY MUTATIONS

BACKGROUND

Rosette-forming glioneuronal tumor (RGNT) is an uncommon CNS tumor originally described in the fourth ventricle characterized by a low-grade glial neoplasm admixed with a rosette-forming neurocytic component.

METHODS

We reviewed clinicopathologic features of 42 patients with RGNT. Targeted next-generation sequencing was performed, and genome-wide methylation profiling is underway.

RESULTS

The 20 male and 22 female patients had a mean age of 25 years (range 3–47) at time of diagnosis. Tumors were located within or adjacent to the lateral ventricle (n=16), fourth ventricle (15), third ventricle (9), and spinal cord (2). All 31 tumors assessed to date contained FGFR1 activating alterations, either in-frame gene fusion, kinase domain tandem duplication, or hotspot missense mutation in the kinase domain (p.N546 or p.K656). While 7 of these 31 tumors harbored FGFR1 alterations as the solitary pathogenic event, 24 contained additional pathogenic alterations within PI3-kinase or MAP kinase pathway genes: 5 with additional PIK3CA and NF1 mutations, 4 with PIK3CA mutation, 3 with PIK3R1 mutation (one of which also contained focal RAF1 amplification), 5 with PTPN11 mutation (one with additional PIK3R1 mutation), and 2 with NF1 deletion. The other 5 cases demonstrated anaplastic features including hypercellularity and increased mitotic activity. Among these anaplastic cases, 3 harbored inactivating ATRX mutations and two harbored CDKN2A homozygous deletion, in addition to the FGFR1 alterations plus other PI3-kinase and MAP kinase gene mutations seen in those RGNT without anaplasia.

CONCLUSION

Independent of ventricular location, RGNT is defined by FGFR1 activating mutations or rearrangements, which are frequently accompanied by mutations involving PIK3CA, PIK3R1, PTPN11, NF1, and KRAS. Whereas pilocytic astrocytoma and ganglioglioma are characterized by solitary activating MAP kinase pathway alterations (e.g. BRAF fusion or mutation), RGNT are genetically more complex with dual PI3K-Akt-mTOR and Ras-Raf-MAPK pathway activation. Rare anaplastic examples may show additional ATRX and/or CDKN2A inactivation.

QOLP-13. IMPACT OF CANNABIS USE ON QUALITY OF LIFE IN PATIENTS WITH CENTRAL NERVOUS SYSTEM TUMORS

BACKGROUND

Nearly 80,000 new cases of primary brain tumors are expected to be diagnosed this year, 32% of CNS tumors are malignant. Anecdotally, patients who report use of cannabis, frequently describe higher quality of life scores (QOL) in standardized instruments. However, the lack of available tools that allow systematic documentation of cannabis use results in a barrier to accurately assess efficacy, potential benefits and risks.

METHODS

We conducted a single center, observational study: patients with primary brain tumors answered a previously validated instrument to explore cannabis use. QOL was assessed using the instruments from the European Organisation for Research and Treatment of Cancer: QLQ-C30 and its complementary module BN-20 as well as the EuroQol instrument EQ-5D-5L. Eligible participants were identified as cannabis users or non-users, completing the instruments in a self-administered fashion.

RESULTS

To date, 51 patients who signed informed consent were enrolled and answered the questionnaires, mean age was 51 (SD 12.95) years, 34 were male, 30 were considered active cannabis users (66.6% males and 33.3% females). The mean global health score in the QLQ-C30 instrument was 68.4 (SD: 20.7) among cannabis users and 82.2 (SD: 17.5) among non-users. The mean difference in QOL scores between users and non-users was 13.8 (95%CI: 2.8, 24.8; p=0.01). In contrast the difference between cannabis users and non-users in QOL index in the EQ-5D-5L instrument was 0.13 (95% CI: 0.06, 0.2; p=0.001). Among cannabis users, patients perceive their symptoms as moderate before using cannabis and mild after using cannabis (p >0.001)

CONCLUSIONS

In our analysis, patients who use cannabis reported, on average, lower QOL scores. Potentially, sicker patients resort to cannabis to improve their symptoms and ultimately quality of life. The perception of patients is that cannabis usage improves overall quality of life. Findings provide support to perform prospective studies.

Identification and characterization of E2F7, a novel mammalian E2F family member capable of blocking cellular proliferation

The mammalian E2F family of transcription factors plays a crucial role in the regulation of cellular proliferation, apoptosis, and differentiation. Consistent with its biological role in a number of important cellular processes, E2F regulates the expression of genes involved in cell cycle, DNA replication, DNA repair, and mitosis. It has proven difficult, however, to determine the specific roles played by the various known family members in these cellular processes. The work presented here now extends the complexity of this family even further by the identification of a novel E2F family member, which we now term E2F7. Like the expression of the known E2F activators, E2F1, E2F2, and E2F3, the expression of E2F7 is growth-regulated, at least in part, through E2F binding elements on its promoter, and its protein product is localized to the nucleus and associates with DNA E2F recognition sites with high affinity. A number of salient features, however, make this member unique among the E2F family. First, the E2F7 gene encodes a protein that possesses two distinct DNA-binding domains and that lacks a dimerization domain as well as a transcriptional activation and a retinoblastoma-binding domain. In contrast to the E2F activators, E2F7 can block the E2F-dependent activation of a subset of E2F target genes as well as mitigate cellular proliferation of mouse embryo fibroblasts. These findings identify E2F7 as a novel member of the mammalian E2F transcription factor family that has properties of a transcriptional repressor capable of negatively influencing cellular proliferation.