Abstracts vii145 NEURO-ONCOLOGY • November 2022 INNV-18. PROLONGED REMISSION AFTER TREATMENT WITH SINGLE-AGENT IBRUTINIB AS MAINTENANCE THERAPY FOLLOWING SALVAGE RADIATION THERAPY FOR REFRACTORY/ RELAPSE PRIMARY CNS LYMPHOMA Steven Du 1 , Daniela Bota 2 , and Xiao-Tang Kong 3 ; 1 University of California, Irvine, Orange, CA, USA, 2 Department of Neurology, University of California, Irvine, Irvine, CA, USA, 3 UC Irvine Health, Irvine, CA, USA INTRODUCTION: Primary central nervous system lymphoma (PCNSL) is a rare and aggressive disease. Standard induction therapy for PCNSL consists of a high-dose methotrexate-based (HD-MTX) regimen. For relapsed or refractory primary CNS lymphoma (r/r PCNSL), most of the non-standard treatment regimens including additional chemo- therapy, stem cell transplant, or whole brain radiation therapy (WBRT) may not reach long-term remission due to intolerance of the treatment by the patients or lack of effects. Here we report a case with r/r PCNSL reached more than 50-month remission after salvage WBRT followed by single agent ibrutinib maintenance therapy. CASE REPORT: a 75-year- old female with PCNSL, experienced disease recurrence, despite under- going multiple lines of treatment including initial HD-MTX, second-line rituximab and temozolomide, repeated HD-MTX, and a clinical trial. Because her disease was refractory to these treatment options, we decided to start WBRT as salvage therapy, which resulted in signifcant reduc- tion of tumor burden. Prior studies, however, showed that r/r PCNSL patients who underwent salvage WBRT alone had a median survival of only 1-2 years. Therefore, to extend the remission after salvage WBRT, she opted to try ibrutinib, a Bruton’s tyrosine kinase inhibitor with past success in treating r/r PCNSL patients, as maintenance therapy after sal- vage WBRT. She tolerated well and decided to be off the treatment after 18 month-maintenance therapy. The patient has been stable clinically. She has since survived for more than 50 months after the completion of salvage WBRT plus maintenance therapy with ibrutinib. DISCUS- SION: Compared to prior reports of 11 to 16 months of median survival after salvage WBRT alone for r/r PCNSL, our case has had prolonged survival, which supports the potential positive effect of ibrutinib as main- tenance therapy for r/r PCNSL after salvage WBRT INNV-19. THE DETECTION OF DISSEMINATED PINEAL PARENCHYMAL TUMOR OF INTERMEDIATE DIFFERENTIATION (PPTID) IN CEREBROSPINAL FLUID (CSF) USING CELL CAPTURE AND IMMUNOCYTOCHEMISTRY Kaitlyn Armijo 1 , Nathan Sweed 1 , Steven Hsiao 1 , Tony Pircher 1 , Mikayla Marrin 1 , Leslie Cho 1 , Kelly Kreitzburg 1 , Barbara Blouw 1 , Deanna Fisher 1 , Michael Dugan 1 , and Santosh Kesari 2 ; 1 Biocept, Inc., San Diego, CA, USA, 2 Providence Saint John’s Health Center, St. John’s Cancer Institute, Santa Monica, CA, USA BACKGROUND: Pineal parenchymal tumors of intermediate dif- ferentiation (PPTID) account for 21% to 54% of pineal parenchymal tumors and may be complicated by cerebrospinal dissemination (most commonly at time of reoccurrence; up to 4-10 years post resection). The integral membrane protein synaptophysin is expressed in neuroendocrine cells and virtually all neuraxial neurons that contribute to synaptic trans- mission. PPTID frequently demonstrates synaptophysin independently of other neural differentiation markers. Cerebrospinal fuid (CSF) cell cap- ture assays have demonstrated utility for assessing disseminated intracra- nial neoplasms, thus we explore this technology for monitoring a patient with PPTID. METHODS: A 30-year-old female patient with PPTID diagnosed two years prior was suspected for intracranial dissemination and underwent fve CSF collections over the course of 64 days. Per col- lection, approximately 7 mL of CSF was submitted for each cytology and cell capture. Cytology was performed at Providence Saint John’s Health Center. The CNSide™ platform (Biocept, Inc.) was used to capture and stain cells for DAPI, synaptophysin, and CD45. Multiple capture anti- body cocktails (termed 1986, 1822, and gTP1—originally developed for use in carcinoma, melanoma, and glioma) were tested. Cells of interest (COI) were defned by positive immunoreactivity for both DAPI and synaptophysin and no immunoreactivity for CD45. Results were quan- tifed and compared longitudinally. RESULTS: CSF analysis on days 0, 9, 21, 36, and 64 demonstrated negative results by cytology and 51, 96, 170, 130, and 43 COI/mL by the CNSide platform, respectively. Cumu- lative mean capture rates for cocktails 1986, 1822, and gTP1 were 47, 14, and 36 COI/mL/sample, respectively. DISCUSSION: A signifcant amount of PPTID patients will develop cerebrospinal dissemination. The importance of craniospinal control in this setting has been previously demonstrated. Our work suggests that cell capture assays paired with immunocytochemistry can be used as sensitive means to monitor dissem- inated PPTID and may impact treatment decisions. INNV-20. INCORPORATING EXPERT OPINIONS INTO THE DEVELOPMENT OF FEARLESS: A PSYCHOTHERAPEUTIC INTERVENTION TARGETING FEAR OF CANCER RECURRENCE IN THOSE WITH BRAIN TUMORS Ashlee Loughan 1 , Sarah Braun 1 , Autumn Lanoye 2 , and Kelcie Willis 1 ; 1 Virginia Commonwealth University, Richmond, USA, 2 Massey Cancer Center, Richmond, USA INTRODUCTION: A brain tumor diagnosis brings about emotional dis- tress, including signifcant fear of cancer recurrence (FCR). Three evidence- based interventions that target FCR exist, but all excluded patients with brain tumors (PwBT) from their effcacy trials. Preliminary evidence suggests that FCR may be categorically different in PwBT compared to other cancer populations, thereby necessitating tailored intervention development. For these reasons, we convened a neuro-oncology Expert Advisory Board (EAB) to assist in the creation of a psychotherapeutic intervention targeting FCR in PwBT. METHODS: The EAB included neuro-oncology professionals, patients, and caregivers (N=7). To facilitate open dialogue, the patients and caregivers (n=3) met separately from the professionals (n=4). The EAB met virtually over fve consecutive weeks to discuss three evidence-based FCR manuals, identify topic applicability, determine medical relevance, and dis- cuss necessary adaptations to meet the specifc needs of PwBT. Readings were provided in advance, two moderators (ARL & SEB) led group discus- sions, and all sessions were recorded following consent. RESULTS: The EAB determined the content contained in the three FCR intervention re- quired tailoring to meet the distinct needs of PwBT. Hypervigilance patterns were determined to be unique for PwBT (e.g., headache, fatigue, word- fnding, auras). Language surrounding uncertainty of progression and inclu- sion of healthcare providers in therapy were less relevant in PwBT. Strategies and skills to enhance acceptance of existential themes were spotlighted. Mindfulness practices were requested. Results called for a blend of three therapeutic orientations: cognitive behavioral therapy, existential therapy, and mindfulness-based therapy. Professionals promoted group intervention delivery, whereas patients and caregivers promoted individual or dyadic sessions. Caregiver participation was unanimously supported. CONCLU- SION: The development of a psychotherapeutic intervention targeting FCR in PwBT offers a distinct opportunity for interdisciplinary and community collaboration. Results from the EAB were overwhelmingly informative, and recommendations will be incorporated into the newly developed FCR inter- vention for PwBT: FearLess. INNV-21. FEASIBILITY OF A VIRTUAL REALITY (VR) INTERVENTION TARGETING DISTRESS AND ANXIETY IN PRIMARY BRAIN TUMOR (PBT) PATIENTS AT THE TIME OF NEUROIMAGING: INTERIM ANALYSIS OF A PHASE 2 CLINICAL TRIAL Amanda King 1 , Kayla Roche 1 , Heather Leeper 1 , Elizabeth Vera 1 , Tito Mendoza 2 , Kelly Mentges 1 , Alvina Acquaye 1 , Kendra Adegbesan 1 , Lisa Boris 1 , Eric Burton 1 , Claudia Chambers 1 , Anna Choi 1 , Alexa Christ 1 , Karen Evans 3 , Ewa Grajkowska 1 , Jason Levine 2 , Matthew Lindsley 1 , Nicole Lollo 1 , Edina Komlodi-Pasztor 3 , Hope Miller 1 , Marissa Panzer 1 , Marta Penas-Prado 1 , Valentina Pillai 1 , Lily Polskin 3 , Jennifer Reyes 1 , James Rogers 1 , Solmaz Sahebjam 3 , Dilorom (Delia) Sass 1 , Dorela Shuboni-Mulligan 1 , Macy Stockdill 1 , Brett Theeler 2 , Kathleen Wall 3 , Alex Wollet 1 , Jing Wu 1 , Mark Gilbert 1 , and Terri Armstrong 1 ; 1 Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA, 2 National Cancer Institute, National Institutes of Health, Bethesda, MD, USA, 3 National Institutes of Health, National Cancer Institute (NCI), Center for Cancer Research (CCR), Neuro-Oncology Branch (NOB), Bethesda, MD, USA BACKGROUND: PBT patients experience high levels of distress and anx- iety symptoms at the time of neuroimaging, yet few non-pharmacological interventions are available. This phase 2 clinical trial interim analysis ex- plored feasibility of a VR relaxation intervention for a PBT population.  METHODS: PBT patients seen at NIH were recruited to participate in this single arm trial conducted via telehealth. English-speaking, adult patients with upcoming neuroimaging who can self-report symptoms and have re- ported distress on previous MD Anderson Symptom Inventory-Brain Tumor assessments were eligible. Exclusion criteria include recent surgery or seiz- ures, anxiety disorders, nausea, or visual defcits. The primary intervention consisted of a brief VR session done within 2 weeks prior to neuroimaging with patient-reported outcomes (PROs) collected before and immediately post-intervention, as well as 1 week and 4 weeks later, with self-directed VR use over 1 month. A qualitative phone interview was also completed to assess patient satisfaction. RESULTS: Fifty-fve patients were screened and approached with 40 (73%) responding to initial reach-out and 20 ul- timately enrolling (9 declines, 11 screen fails). Decline reasons included: no distress/anxiety (30%), treatment-related toxicities (11%), and unknown (59%). Seven (64%) failed screening due to exclusionary anxiety disorders (36% GAD, 18% PTSD, 9% claustrophobia). Of those enrolled, 65% were ≤ 50 years, 50% were male, 90% were White/non-Hispanic, 85% had good KPS ( > 80), 65% had high-grade tumors, and most were on active treat- ment. All enrolled patients completed the VR intervention and participation Downloaded from https://academic.oup.com/neuro-oncology/article/24/Supplement_7/vii145/6826488 by guest on 17 February 2023