Consulting a neurosurgeon upon initial medical assessment reduces the time to the first surgery and potentially contributes to improved prognosis for glioblastoma patients

BACKGROUND

The neurological status of glioblastoma patients rapidly deteriorates. We recently demonstrated that early diagnosis and surgery within 3 weeks from the initial symptoms are associated with improved survival. While glioblastoma is a semi-urgent disease, the prehospital behaviors and clinical outcomes of glioblastoma patients are poorly understood. We aimed to disclose how prehospital patient behavior influences the clinical outcomes of glioblastoma patients.

METHODS

Isocitrate dehydrogenase-wildtype glioblastoma patients treated at our institution between January 2010 and December 2019 were reviewed. Patients were divided into two groups, neurosurgeon and non-neurosurgeon groups, based on the primary doctor whom patients sought for an initial evaluation. Patient demographics and prognoses were examined.

RESULTS

Of 170 patients, 109 and 61 were classified into the neurosurgeon and non-neurosurgeon groups, respectively. The median age of neurosurgeon group was significantly younger than the non-neurosurgeon group (61 vs. 69 years old, P = 0.019) and in better performance status (preoperative Karnofsky performance status scores $\ge$80: 72.5 vs. 55.7%, P = 0.027). The neurosurgeon group exhibited a significantly shorter duration from the first hospital visit to the first surgery than the non-neurosurgeon group (18 vs. 29 days, P < 0.0001). Furthermore, the overall survival of the neurosurgeon group was significantly more prolonged than that of the non-neurosurgeon group (22.9 vs. 14.0 months, P = 0.038).

CONCLUSION

Seeking an initial evaluation by a neurosurgeon was potentially associated with prolonged survival in glioblastoma patients. A short duration from the first hospital visit to the first surgery is essential in enhancing glioblastoma patient prognosis.

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

BACKGROUND

Treatment of brain metastases (BMs) from colorectal cancer (CRC) has transitioned with the expansion of indications for stereotactic radiotherapy. Our study aimed to assess changes in prognosis and prognostic factors associated with changes in treatment for BMs from CRC.

METHODS

We retrospectively surveyed treatments for and outcomes of BMs from CRC in 208 patients treated during 1997-2018. Patients were divided into two groups according to time of BM diagnosis, i.e., 1997-2013 ("first period") and 2014-2018 ("second period"). We compared overall survival between the periods and assessed how the transition impacted prognostic factors affecting overall survival, including the following prognostic factors such as Karnofsky performance status (KPS), volume-related factors (BM number and diameter), and BM treatment modalities as covariates.

RESULTS

Of the 208 patients, 147 were treated in the first period and 61 in the second period. Whole-brain radiotherapy use decreased from 67 to 39% in the second period, and stereotactic radiotherapy use increased from 30 to 62%. Median survival after BM diagnosis improved from 6.1 to 8.5 months (p = 0.0272). Multivariate analysis revealed KPS, control of primary tumor, stereotactic radiotherapy use, and chemotherapy history as independent prognostic factors during the entire observation period. Hazard ratios of KPS, primary tumor control, and stereotactic radiotherapy were higher in the second period, whereas prognostic impact of chemotherapy history before BM diagnosis was similar in both periods.

CONCLUSION

Overall survival of patients with BMs from CRC improved since 2014, which can be attributed to advances in chemotherapy and the more widespread use of stereotactic radiotherapy.

A retrospective analysis of the prognosis of Japanese patients with sarcoma brain metastasis

BACKGROUND

Bone and soft tissue sarcomas are rare tumors and extremely rarely metastasize to the brain. Previous studies have examined the characteristics and poor prognostic factors in cases of sarcoma brain metastasis (BM). Due to the rarity of cases of BM from sarcoma, limited data exist concerning the prognostic factors and treatment strategies.

METHODS

A retrospective single-center study was performed on sarcoma patients with BM. The clinicopathological characteristics and treatment options for BM of sarcoma were investigated to identify predictive prognostic factors.

RESULTS

Between 2006 and 2021, 32 patients treated for newly diagnosed BM at our hospital were retrieved among 3133 bone and soft tissue sarcoma patients via our database. The most common symptom was headache (34%), and the most common histological subtypes were alveolar soft part sarcoma (ASPS) and undifferentiated pleomorphic sarcoma (25%). Non-ASPS (p = 0.022), presence of lung metastasis (p = 0.046), a short duration between initial metastasis, and the diagnosis of brain metastasis (p = 0.020), and the absence of stereotactic radiosurgery for BM (p = 0.0094) were significantly correlated with a poor prognosis.

CONCLUSIONS

In conclusion, the prognosis of patients with brain metastases of sarcomas is still dismal, but it is necessary to be aware of the factors associated with a relatively favorable prognosis and to select treatment options appropriately.

Utility of real-time polymerase chain reaction for the assessment of CDKN2A homozygous deletion in adult-type IDH-mutant astrocytoma

The World Health Organization Classification of Tumors of the Central Nervous System 5th Edition (WHO CNS5) introduced a newly defined astrocytoma, IDH-mutant grade 4, for adult diffuse glioma classification. One of the diagnostic criteria is the presence of a CDKN2A/B homozygous deletion (HD). Here, we report a robust and cost-effective quantitative polymerase chain reaction (qPCR)-based test for assessing CDKN2A HD. A TaqMan copy number assay was performed using a probe located within CDKN2A. The linear correlation between the Ct values and relative CDKN2A copy number was confirmed using a serial mixture of DNA from normal blood and U87MG cells. The qPCR assay was performed in 109 IDH-mutant astrocytomas, including 14 tumors with CDKN2A HD, verified either by multiplex ligation-dependent probe amplification (MLPA) or CytoScan HD microarray platforms. Receiver operating characteristic curve analysis indicated that a cutoff value of 0.85 yielded optimal sensitivity (100%) and specificity (99.0%) for determining CDKN2A HD. The assay applies to DNA extracted from frozen or formalin-fixed paraffin-embedded tissue samples. Survival was significantly shorter in patients with than in those without CDKN2A HD, assessed by either MLPA/CytoScan or qPCR. Thus, our qPCR method is clinically applicable for astrocytoma grading and prognostication, compatible with the WHO CNS5.

Clinical characteristics and prognosis of Glioblastoma patients with infratentorial recurrence

BACKGROUND

Glioblastoma (GBM) infrequently recurs in the infratentorial region. Such Infratentorial recurrence (ITR) has some clinically unique characteristics, such as presenting unspecific symptoms and providing patients a chance to receive additional radiotherapy. However, the clinical significances of ITR are not well studied.

METHODS

We reviewed newly diagnosed isocitrate dehydrogenase (IDH)-wildtype GBM patients treated at our institution between October 2008 and December 2018. ITR was defined as any type of recurrence in GBM, including dissemination or distant recurrence, which primarily developed in the supratentorial region and recurred in the infratentorial region.

RESULTS

Of 134 patients with newly diagnosed IDH-wildtype GBM, six (4.5%) were classified as having ITR. There was no significant difference in median duration from the first surgery to ITR development between patients with and without ITR (12.2 vs. 10.2 months, P = 0.65). The primary symptoms of ITR were gait disturbance (100%, n = 6), dizziness (50.0%, n = 3), nausea (33.3%, n = 2), and cerebellar mutism (16.7%, n = 1). In four cases (66.7%), symptoms were presented before ITR development. All patients received additional treatments for ITR. The median post-recurrence survival (PRS) of ITR patients was significantly shorter than that of general GBM patients (5.5 vs. 9.1 months, P = 0.023). However, chemoradiotherapy contributed to palliating symptoms such as nausea.

CONCLUSIONS

ITR is a severe recurrence type in GBM patients. Its symptoms are neurologically unspecific and can be overlooked or misdiagnosed as side effects of treatments. Carefully checking the infratentorial region, especially around the fourth ventricle, is essential during the GBM patient follow-up.

RT-8 POST-IRRADIATION COURSE OF GLIOMAS OF THALAMUS AND BRAINSTEM

Objective

We retrospectively reviewed the post-irradiation course of cases treated with radiotherapy for the gliomas involving thalamus or brainstem.

Methods

Thirty-seven gliomas involving thalamus or brainstem treated with radiotherapy from 2007 to 2021 in our hospital were included. Median age was 47 (19-79) years, and KPS at the start of irradiation was 80% or less in 26 cases. Tumor localization was thalamus only/brainstem only/both thalamus and brainstem for 20/9/8 cases. Two cases did not undergo biopsy, and the others underwent surgery before irradiation. Two cases underwent partial excision of the lesion near the thalamus, 6 cases underwent partial excision from other than the thalamus-brainstem, and 27 cases underwent biopsy only. The pathological diagnosis based on the WHO classification at the time of surgery was glioblastoma (GBM) in 8 cases, high-grade glioma other than glioblastoma (HGG) in 23 cases (including 9 cases of diffuse midline glioma K27M), and low-grade glioma (LGG) in 6 cases.

Results

Median observation period was 16(2-66) months. Median PFS/median OS/5-year OS rate were 13 months/25 months/20% in all 37 cases. Median PFS was 66/18/7 months for LGG/ HGG/ GBM, and 5-year OS was 75/16/15%. Symptomatic cerebral edema associated with tumor growth was observed in one GBM 9 months after irradiation. In HGG, 7/23 cases underwent the VP shunting before irradiation, and one case who underwent ventriculostomy before irradiation had a VP shunting created for worsening hydrocephalus 3 months after irradiation. In one case of GBM, a VP shunt was created immediately after surgery.

Conclusions

Compared to the past reports of gliomas, it was suggested that the localization in thalamic brainstem was a factor for a worse prognosis in HGG.

ACT-19 A REPORT OF PHASE I PART OF PHASE I/II STUDY OF MAINTENANCE THERAPY WITH METFORMIN AND TEMOZOLOMIDE FOR GLIOBLASTOMA

Background

Glioblastoma (GBM) is an aggressive primary brain tumor with poor prognosis. One strategy for overcoming resistance is developing a new therapy targeting the cancer stem/initiating cells. We have shown that the antidiabetic drug metformin (MF) can induce differentiation of stem-like glioma-initiating cells and suppress tumor formation through AMPK-FOXO3 activation. We conducted a phase I/II study to examine the clinical effect of MF combined with standard maintenance temozolomide (TMZ). Here, we report the result of phase I part and the current status of phase II part.

Patients and Methods

Patients between 20 and 74 years of age with supratentorial GBM histologically diagnosed according to the World Health Organization 2016 classification were eligible. MF dose-escalation was planned using a 3 + 3 design. Dose-limiting toxicities (DLTs) were assessed during the first 6 weeks after MF initiation.

Results

Between February 2021 and January 2022, the first three patients were treated with 1,500 mg/day MF and the next four patients were treated with 2,250 mg/day MF, which is the maximum dose approved in Japan. The median age of the patients was 41 years. Three tumors (42.9 %) were IDH1/2 mutants and 4 (57.1 %) were IDH1/2 wild-types. No DLTs were observed. The most common adverse effects were appetite loss, nausea, and diarrhea, which were observed in three patients. All of them were manageable, with grade 1 or 2. Only one grade 3 seizure was reported, which was likely related to the tumor. Two patients experienced tumor progression at 6.0 and 6.1 months, and one died 12.2 months after initial surgery. The other five patients remained stable at the last follow-up.

Conclusion

MF dose of up to 2,250 mg/day combined with maintenance TMZ appeared to be well tolerated, and we proceeded to phase II study with 2,250 mg/day MF.

NQPC-10 IMPACT OF HEALTH-RELATED QOL (HRQOL) IN THE FIRST SIX MONTHS AFTER SURGERY ON LONG-TERM POSTOPERATIVE GENERAL HEALTH STATUS IN GLIOMA PATIENTS

Purpose

Though prolonging survival is often the focus of brain tumor therapy, evaluation of health-related quality of life (HRQoL) is important in postoperative follow-up since treatment-induced side effects or tumor-induced functional impairment could affect HRQoL.In glioma treatment, we investigated the relationship between patient-reported HRQoL assessment from 1 month preoperatively to 6 months postoperatively and overall health status at 1 year and 1.5years postoperatively.

Methods

Thirty-one glioma patients who underwent surgical treatment at our hospital and the National Cancer Center Hospital from May 2011 to August 2022 were included in this study. HRQoL and KPS were evaluated at 1 month before surgery, 6 months, 1 year and 1.5 years after surgery, respectively. The median age was 47 years, 15 (48%) were men and 16 (52%) were women. Pathological results were GBM in 19 (61%), AA in 4 (13%), AO in 2 (6%), and others in 6 (19%). The EORTC QLQ-C30/BN20 was used as a measure of HRQoL, and eligible patients answered each of the 50 questions on a 4-point scale, with scores calculated for 26 QoL status items. Bivariate analysis (Wilcoxon test) was performed on the 26 HRQoL items and KPS.

Results/Consideration

High KPS(≥70)was seen in patients who perceived themselves at 6 months postoperatively, to be “good” in the following 10 items “Physical functioning,” “Role functioning,” “Cognitive functioning,” “Global health status,” “Fatigue,” “Constipation,” “Motor dysfunction,” Communication deficit,” “Itchy skin” and “Weakness of legs. “In addition, patients who perceived their HRQoL conditions of” Sleep disturbance,”“ Future Uncertain,”and “ Bladder control”to be “good” after 6 months had a KPS of 70 or higher at 1.5 years.

Conclusions

The results suggest that long-term systemic status can also be monitored by assessing HRQoL in the first six months after surgery. Patient evaluation including sequential HRQoL is important in the treatment of glioma.

MET-14 OUTCOME OF METASTATIC CEREBELLAR TUMOR: A SINGLE-CENTER STUDY

Background

Brain metastases (BM) to the cerebellum account for approximately 20% of all of BM. From the results of JCOG0504 clinical trial, observation with salvage SRS (stereotactic radiosurgery) has been established as a standard therapy for a patient after complete resection of BM. However, we often experience early local recurrence after resection of cerebellar BM, therefore, we retrospectively analyzed them to consider the appropriate timing of SRS.

Methods

We extracted surgical cases with cerebellar BM from January 2015 to March 2022 and analyzed the patient characteristics, treatment content, postoperative intracranial progression-free survival (IC-PFS) and postoperative overall survival (OS).

Results

A total of 57 cases were enrolled (male: female = 43.9%: 56.1%) in this study. The median age was 61.9 years (51.9-68.2). The common primary lesions were NSCLC (31.6%), colorectal cancer (19.3%), and breast cancer (17.5%). The IC-PFS was 4.5 months (2.6-5.7) and the OS was 11.6 months (9.1-21.8), but the local recurrent rate within 3 months was 43.4%. The rate of patients with leptomeningeal metastases (LMM) at the first recurrence was 26.3%, significantly higher than 7.7% in JCOG0504 (p=0.000224). In the postoperative observation group (no SRS within a month), the OS was 25.3 months (11.6-NA), which was longer than the 15.6 months (11.4-20.8) of JCOG0504. RT was performed in 18 patients at the recurrence (SRS: 15, WBRT (whole-brain radiotherapy): 9). SRS was the only factor that prolonged the OS (25.2 vs. 6.1 months (p=0.0212)). Furthermore, in the patients who underwent radiotherapy within 1 month after surgery, postoperative SRS (10.2 vs. 3.1 months, p=0.00437), and postoperative SRS to the resection cavity (11.0 vs. 3.7mo, p=0.0012) significantly prolonged the OS.

Conclusion

Since cerebellar BM has high recurrence and frequent LMM, early SRS for a resected cavity after surgery might lead to more favorable outcomes in cerebellar BM patients.

NQPC-1 INSIGHTS FROM PREOPERATIVE FATIGUE ASSESSMENT IN GLIOMA PATIENTS

Introduction

Glioma is a rare type of tumor, and the research on fatigue and QOL in glioma patients is limited. Research from other countries has reported patients with intense fatigue in the preoperative stage, but no similar studies could be found in Japan. In the present study, we report a retrospective investigation of fatigue assessment performed during preoperative rehabilitation evaluation.

Participants and Methods

Participants were 90 patients admitted to the hospital for glioma surgery between January 2016 and December 2020 who underwent five specific preoperative evaluations: KPS, MMSE, Motor-Functional Independence Measure (Motor FIM), Cancer Fatigue Scale (CFS), and grip strength. Participants were divided into a CFS-High(CFS-H) group (CFS&gt;19 points) and a CFS-Low (CFS-L) group (CFS&lt;18 points), and participant attributes, MMSE, Motor FIM, and grip strength compared. Between-group comparisons used the Mann-Whitney U test.

Results

Participants were 90 patients with high-grade glioma. Fifty-seven were men, and the median age was 45 (15-81). Thirty-three participants (37%) had intense fatigue before surgery (CFS-H group: 33 participants, CFS-L group: 57 participants). In the CFS-H group and CFS-L group respectively, age was 46.5/44 (p=0.36), MMSE was 24 points/29 points (p=0.00255), Motor FIM was 89 points/91 points (p=0.0383), and grip strength was 22.2kg/25.5kg (p=0.194).

Discussion

The present study suggests that some Japanese high-grade glioma patients also experience intense fatigue before surgery. Compared to patients with low fatigue, those with high fatigue were suggested to have significant declines in cognitive function and ADL.

ML-12 HIGH-DOSE CHEMOTHERAPY AND AUTOLOGOUS STEM CELL TRANSPLANTATION (HDC-ASCT) FOR THE PATIENTS WITH PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMA (PCNSL)

High-dose chemotherapy and autologous stem-cell transplantation (HDC-ASCT) for the patient with primary central nervous system lymphoma (PCNSL) has been used as treatment at relapse or as consolidation therapy. We report on the efficacy, safety, and future issues of HDC-ASCT. Twelve patients with PCNSL (10 males and 2 females) underwent HDC-ASCT, ranging in age from 45 to 66 years (median 58 years) and KPS from 70 to 100 (median 90) at the time of HDC-ASCT. HDC-ASCT was performed at the time of consolidation therapy (without radiation) in 7 patients, at first recurrence in 4 (including 1 without radiation), and at second recurrence in 1. Department of Neurosurgery and Neuro-Oncology (NSNO) was in charge from diagnosis to just before transplantation, Department of Hematopoietic Stem Cell Transplantation (HSCT) was in charge of HDC-ASCT, and Department of NSNO was in charge after discharge again. The conditioning regimen consisted of busulfan 3.2mg/kg/day for 4 days and thiotepa 5mg/kg/day for the 2 following days, followed by ASCT. The observation period after HDC-ASCT ranged from 2.8 to 43 months (median 16.1 months), and the hospitalization period for HDC-ASCT ranged from 26 to 38 days (median 33 days), with no serious complications. All patients have returned to society and there have been no deaths to date, but two patients (after 4.7 months and 10.9 months) had relapses, of which two were treated with tirabrutinib, and one was subsequently treated palliatively. HDC-ASCT in PCNSL is an important option to improve outcomes. Since the main focus of this treatment is Department of HSCT, it is important to have sufficient cooperation and communication among the departments from the time of tumor diagnosis until after the patient is discharged from transplantation, and it is essential to be fully aware of each role.

COT-8 DEVELOPMENT OF TARGETED GENE PANEL FOR RAPID MOLECULAR DIAGNOSIS OF BRAIN TUMORS

Background

Brain tumors are diagnosed based on pathological and genetic features defined by WHO classification. Although targeted gene panels are clinically available, most of them do not cover all the necessary genes for the diagnosis of brain tumors. Moreover, broad copy number analysis, which the current WHO classification requires, usually lacks in the gene panel. Another problem is that those panels demand a high burden of time and cost, which disturbs rapid diagnosis and broad application. To overcome those problems, we developed a rapid and cost-effective workflow of molecular diagnosis for brain tumors.

Methods

Our panel contains 109 genes of which 68 are necessary for fundamental molecular diagnosis and 41 are other common driver genes. To detect copy number changes and structural variants, which generate a fused gene, additional probes are placed on common SNPs and introns containing common breakpoints. MGMT methylation status is examined at the same time using bisulfite-converted DNA amplification. Sequencing data is analyzed using a supercomputer.

Results

The analysis time is within 4 days: 2 days for library preparation, 1 day for sequencing, and 12 hours for analysis. Detected driver alterations were validated by whole genome sequencing data. MGMT methylation status was correlated between the results of our workflow and pyrosequencing.

Conclusions

We have developed a rapid comprehensive molecular analysis workflow that detects genetic alterations and MGMT methylation. Our method allows a cost-effective molecular diagnosis with high accuracy, which would improve molecular diagnosis for brain tumors.

PEDT-12 NATIONWIDE LANDSCAPE OF GENOMIC ANALYSIS OF PEDIATRIC CENTRAL NERVOUS SYSTEM TUMORS

Background and Purpose

In Japan, cancer-gene profiling (CGP) tests, such as the OncoGuide NCC Oncopanel System, FoundationOne CDx Cancer Genome Profile (F-one), and FoundationOne Liquid CDx Cancer Genome Profile, are covered by insurance and clinically applied to promote cancer genomic medicine. Information from CGP tests is managed at the Center for Cancer Genomics and Advanced Therapeutics (C-CAT) and shared with clinicians after discussions at the Expert Panel (EP). We provide an overview of the registered pediatric CNS tumors.

Methods

We extracted and analyzed CNS/brain data from the C-CAT registry from June 2019 to June 2022 for ages 0–19 years. Variables such as age, gender, histopathological diagnosis, CGP test type, ECOG Performance Status (PS), registration status, genetic abnormalities, and treatments were analyzed.

Results

Among 1133 patients of all ages with CNS tumors, 361 (31.9%) were aged 0–19 years; Of the 918 patients aged 0-19 years with any type of cancer, those with CNS tumors accounted for 34.2%; 188 patients were aged under 10 years, 173 patients were teenagers, 174 patients were males, 187 patients were females; PS was 0 in 47.9% of patients. The most common histopathological diagnoses were medulloblastoma, diffuse midline glioma and glioblastoma. Genetic abnormalities included TP53 mutations in 85 cases, H3F3A mutations in 38 cases, STK11 mutations in 36 cases, BRAF mutations in 33 cases, BRAF-KIAA1549 fusions in 24 cases, and TMB high in 16 cases. Seventy-six patients (21.1%) were offered treatment options in the EP, and 26 patients (7.2%) received the recommended treatment, including two in physician-initiated trials, four in company trials, eleven in treatments within insurance coverage, and eleven in others.

Discussion

This is the first report of genetic analysis of pediatric CNS tumors on a nationwide scale. Pediatric CNS tumors have a large number of registered cases; thus, drug development for them is urgently needed.

COT-16 NATION-WIDE LANDSCAPE OF GENOMIC ANALYSIS OF ADULT CENTRAL NERVOUS SYSTEM TUMORS IN JAPAN

Background

Comprehensive genomic profiling (CGP) testing has been covered by public health insurance and its clinical application has started in Japan since June 2019. All the results of CGP testing are sent to the Center for Cancer Genomics and Advanced Therapeutics (C-CAT) and shared with clinicians after discussion at the Expert Panel (EP). Here we report the results of analysis of adult central nervous system (CNS) tumors registered in Japan.

Methods

C-CAT registry data as of April 2022 (ver. 20220406) was used. Patient background, diagnosis, type of CGP testing, genetic alterations and treatment status after EP were analyzed.

Results

1042 patients with CNS tumors were enrolled, 338 (32.4%) were younger than 20 years old and 704 (67.6%) were older. Among 704 adult patients, mean age was 47.6 years and median ECOG PS was 1. Top tumor diagnosis included glioblastoma (42.8%), anaplastic astrocytoma (11.8%) and anaplastic oligodendroglioma (5.0%), and 634 (90.0%) were tested with FoundationOne CDx(R). Regarding genomic alterations, 278 had TP53 mutation, 242 had CDKN2A deletion, 221 had TERT mutation, 218 had CDKN2B deletion, 136 had IDH1 mutation, and 39 had TMB high (&gt;10Mb) and no NTRK gene fusion was observed. EP recommended treatment options in 187 cases (26.6%) and 60 cases (8.5%) reached therapeutic agents, including 25 Patient-Proposed Healthcare Services, 16 approved drugs, 8 pharmaceutical clinical trials, 7 investigator-initiated clinical trials and 4 others.

Conclusion

This is the first report of nation-wide results of CNS tumors analyzed by CGP in Japan. Although some patients were able to reach therapeutic agents under the Patient-Proposed Healthcare Services system, little number of patients reached clinical trial. Development of new drugs is urgently warranted.

Early Diagnosis and Surgical Intervention Within 3 Weeks From Symptom Onset Are Associated With Prolonged Survival of Patients With Glioblastoma

BACKGROUND

Glioblastoma (GBM) is a rapidly growing and most life-threatening malignant brain tumor. The significance of early treatment to the clinical outcomes of patients with GBM is unclear.

OBJECTIVE

To determine whether early diagnosis and surgery improve the preoperative and postoperative Karnofsky performance status (KPS) and prognosis of patients with GBM.

METHODS

Data of isocitrate dehydrogenase-wildtype patients with GBM treated at our institution between January 2010 and December 2019 were reviewed. Patients were classified into early or late diagnosis groups with a threshold of 14 days from initial symptoms. In addition, patients were divided into early, intermediate, and late surgery groups with thresholds of 21 and 35 days. Representative symptoms and patient prognoses were examined.

RESULTS

Of 153 patients, 72 and 81 were classified into the early and late diagnosis groups. The median tumor volume was significantly smaller in the former group. The proportion of patients with preoperative KPS scores 90 was 48.6% and 29.6% in the early and late diagnosis groups ( P = .016). The early, intermediate, and late surgery groups included 43, 24, and 86 patients. The median overall survival was significantly longer in the early surgery group than in the late surgery group (28.4 vs 18.7 months, P = .006). Multivariate analysis demonstrated that significant predictors of shorter survival included extent of tumor resection (partial or biopsy), preoperative and postoperative KPS 60, and O6-methylguanine-DNA-methyltransferase promoter status (unmethylated).

CONCLUSION

Early diagnosis within 2 weeks and surgical interventions within 3 weeks from the symptom onset are associated with prolonged patient survival. Early GBM treatment will benefit patients with GBM.

Combination of asleep and awake craniotomy as a novel strategy for resection in patients with butterfly glioblastoma: Two case reports

Background:

Several studies have reported that gross total resection contributes to improved prognosis in patients with butterfly glioblastoma (bGBM). However, it sometimes damages the corpus callosum and cingulate gyrus, leading to severe neurological complications.

Case Description:

We report two cases of bGBM that was safely and maximally resected using brief and exact awake mapping after general anesthesia. Two patients had butterfly tumors in both the frontal lobes and the genu of the corpus callosum. Tumor resection was first performed on the nondominant side under general anesthesia to shorten the resection time and maintain patient concentration during awake surgery. After that, awake surgery was performed for the lesions in the dominant frontal lobe and genu of the corpus callosum. Tumor resection was performed through minimal cortical incisions in both frontal lobes. Postoperative magnetic resonance imaging showed gross total resection, and the patients had no chronic neurological sequelae, such as akinetic mutism and abulia.

Conclusion:

bGBM could be safely and maximally resected by a combination of asleep and brief awake resection, which enabled patients to maintain their attention to the task without fatigue, somnolence, or decreased attention. The bilateral approach from a small corticotomy can avoid extensive damage to the cingulate gyrus.

Metformin with Temozolomide for Newly Diagnosed Glioblastoma: Results of Phase I Study and a Brief Review of Relevant Studies

Glioblastoma (GBM) inevitably recurs due to a resistance to current standard therapy. We showed that the antidiabetic drug metformin (MF) can induce the differentiation of stem-like glioma-initiating cells and suppress tumor formation through AMPK-FOXO3 activation. In this study, we design a phase I/II study to examine the clinical effect of MF. We aim to determine a recommended phase II MF dose with maintenance temozolomide (TMZ) in patients with newly diagnosed GBM who completed standard concomitant radiotherapy and TMZ. MF dose-escalation was planned using a 3 + 3 design. Dose-limiting toxicities (DLTs) were assessed during the first six weeks after MF initiation. Three patients were treated with 1500 mg/day MF and four patients were treated with 2250 mg/day MF between February 2021 and January 2022. No DLTs were observed. The most common adverse effects were appetite loss, nausea, and diarrhea, all of which were manageable. Two patients experienced tumor progression at 6.0 and 6.1 months, and one died 12.2 months after initial surgery. The other five patients remained stable at the last follow-up session. The MF dose of up to 2250 mg/day combined with maintenance TMZ appeared to be well tolerated, and we proceeded to a phase II study with 2250 mg/day MF.

Olfactory Preservation in Craniofacial Resection of Tumor Invading Hemianterior Skull Base: Operative Video

In traditional craniofacial resection of tumors invading the anterior skull base, the bilateral olfactory apparatus is resected. Recently, transnasal endoscopy has been used for olfactory preservation in resections of unilateral low-grade malignancies. However, for tumors that invade the orbita or for high-grade malignancies, the transnasal endoscopic skull base surgery has been controversial. This video demonstrates the surgical techniques of olfactory preservation during craniofacial resection of a high-grade malignancy invading the hemianterior skull base and orbita.

We present the case of a 32-year-old woman with osteosarcoma in the right ethmoid sinus. The tumor invaded the ipsilateral cribriform plate, dura menta, and orbital periosteum; however, the nasal septum and crista galli were intact ( Fig. 1A, B ). Because the tumor was a high-grade malignancy and the orbita had been invaded, we performed craniofacial resection instead of endoscopic resection ( Fig. C2A ). We drilled into the right side of the crista galli, midline of the cribriform plate, and perpendicular plate of the ethmoid bone via craniotomy. As a result, we accessed the nasal cavity directly ( Fig. 2B ). To preserve the nasal septum, we detached the remaining right septal mucosa through the transfacial approach ( Fig. 2C ). Because of the high risk of cerebrospinal fluid leakage as a result of previous irradiation, we performed vascularized free flap reconstruction of the skull base instead of pericranial flap.

Postoperative computed tomography revealed no evidence of tumor ( Fig. 1C, D ). The patient's sense of smell returned after 1 postoperative day, and she was discharged on the postoperative day 14.

The link to the video can be found at: https://youtu.be/XzPABYwzkjs .

Clinical application of a highly sensitive digital PCR assay to detect a small fraction of IDH1 R132H-mutant alleles in diffuse gliomas

The current World Health Organization classification of diffuse astrocytic and oligodendroglial tumors requires the examination of isocitrate dehydrogenase 1 (IDH1) or IDH2 mutations. Conventional analysis tools, including Sanger DNA sequencing or pyrosequencing, fail in detecting these variants of low frequency owing to their limited sensitivity. Digital polymerase chain reaction (dPCR) is a recently developed, highly sensitive, and precise quantitative rare variant assay. This study aimed to establish a robust limit of quantitation of the dPCR assay to detect a small fraction of IDH1 R132H mutation. The dPCR assays with serially diluted IDH1 R132H constructs detected 0.05% or more of mutant IDH1 R132H in samples containing mutant DNA. The measured target/total value of the experiments was proportional to the dilution factors and was almost equal to the actual frequencies of the mutant alleles. Based on the average target/total values, together with a twofold standard deviation of the normal DNA, a limit of quantitation of 0.25% was set to secure a safe margin to judge the mutation status of the IDH1 R132H dPCR assay. In clinical settings, detecting IDH1 R132H using dPCR assays can validate ambiguous immunohistochemistry results even when conventional DNA sequencing cannot detect the mutation and assure diagnostic quality.

Continuing maintenance temozolomide therapy beyond 12 cycles confers no clinical benefit over discontinuation at 12 cycles in patients with IDH1/2-wildtype glioblastoma

OBJECTIVE

The optimal duration of maintenance temozolomide therapy is controversial. We aimed to examine the clinical benefits of continuing temozolomide therapy beyond 12 cycles in patients with glioblastoma.

METHODS

We included 41 patients with isocitrate dehydrogenase 1/2-wildtype glioblastoma, who received 12 or more cycles of temozolomide therapy between June 2006 and December 2019. We evaluated the outcome between 16 patients who continued temozolomide therapy beyond 12 cycles up to 24 cycles (≥13 cycles group) and 25 patients wherein temozolomide therapy was discontinued at 12 cycles (12 cycles group).

RESULTS

The median progression-free survival and survival time after completing 12 cycles (residual progression-free survival and residual overall survival) did not differ between the 12 cycles group and ≥13 cycles group (residual progression-free survival: 11.3 vs. 9.2 months, P = 0.61, residual overall survival: 25.7 vs. 30.2 months, P = 0.76). Multivariate analysis including temozolomide therapy beyond 12 cycles, age at 12 cycles, Karnofsky performance status at 12 cycles, residual tumor at 12 cycles, maintenance therapy regimen and O-6-methylguanine deoxyribonucleic acid methyltransferase promoter methylation status revealed that extended temozolomide therapy beyond 12 cycles was not correlated with residual progression-free survival and residual overall survival (P = 0.80 and P = 0.41, respectively) but Karnofsky performance status at 12 cycles ≥80 was significantly associated with increased residual overall survival (P = 0.0012).

CONCLUSIONS

Continuing temozolomide beyond 12 cycles confers no clinical benefit over the discontinuation of temozolomide at 12 cycles. Karnofsky performance status at 12 cycles ≥80 may serve as a novel predictive factor for long-term survival.

The first-in-human phase I study of a brain-penetrant mutant IDH1 inhibitor DS-1001 in patients with recurrent or progressive IDH1-mutant gliomas

BACKGROUND

Approximately 70% of lower-grade gliomas harbor isocitrate dehydrogenase 1 (IDH1) mutations, resulting in the accumulation of oncometabolite D-2-hydroxyglutarate (D-2-HG); this leads to epigenetic dysregulation, oncogenesis, and subsequent clonal expansion. DS-1001 is an oral brain-penetrant mutant IDH1 selective inhibitor. This first-in-human study investigated the safety, pharmacokinetics, pharmacodynamics, and efficacy of DS-1001.

METHODS

This was a multicenter, open-label, dose-escalation, phase I study of DS-1001 for recurrent/progressive IDH1-mutant (R132) glioma (N = 47) (NCT03030066). DS-1001 was administered orally at 125-1400 mg twice daily. Dose-escalation used a modified continual reassessment method.

RESULTS

The maximum tolerated dose was not reached. Eight patients were continuing treatment at the data cutoff. Most adverse events (AEs) were grade 1-2. Twenty patients (42.6%) experienced at least 1 grade 3 AE. No grade 4 or 5 AEs or serious drug-related AEs were reported. Common AEs (>20%) were skin hyperpigmentation, diarrhea, pruritus, alopecia, arthralgia, nausea, headache, rash, and dry skin. The objective response rates were 17.1% for enhancing tumors and 33.3% for non-enhancing tumors. Median progression-free survival was 10.4 months (95% confidence interval [CI], 6.1 to 17.7 months) and not reached (95% CI, 24.1 to not reached) for the enhancing and non-enhancing glioma cohorts, respectively. Seven on-treatment brain tumor samples showed a significantly lower amount of D-2-HG compared with pre-study archived samples.

CONCLUSIONS

DS-1001 was well tolerated with a favorable brain distribution. Recurrent/progressive IDH1-mutant glioma patients responded to treatment. A study of DS-1001 in patients with chemotherapy- and radiotherapy-naïve IDH1-mutated WHO grade 2 glioma is ongoing (NCT04458272).

Assessment of therapeutic outcome and role of reirradiation in patients with radiation-induced glioma

Background

We sought to clarify the optimal follow-up, therapeutic strategy, especially the role of reirradiation, and the diagnostic impact of isocitrate dehydrogenase (IDH) 1 and 2 mutation status in patients with radiation-induced glioma (RIG).

Methods

We retrospectively reviewed the clinical characteristics and treatment outcomes of 11 patients with high-grade glioma who satisfied Cahan’s criteria for RIG in our database during 2001–2021. IDH 1/2 mutations were analyzed by Sanger sequencing and/or pyrosequencing.

Results

The RIGs included glioblastoma with IDH 1/2 wild-type (n = 7), glioblastoma not otherwise specified (n = 2), anaplastic astrocytoma with IDH1/2 wild-type (n = 1), and anaplastic astrocytoma not otherwise specified (n = 1). The median period from primary disease and RIG diagnosis was 17 years (range: 9–30 years). All patients underwent tumor removal or biopsy, 5 patients postoperatively received reirradiation combined with chemotherapy, and 6 patients were treated with chemotherapy alone. The median progression-free and survival times were 11.3 and 28.3 months. The median progression-free survival time of patients treated with reirradiation and chemotherapy (n = 5) tended to be longer than that of patients that received chemotherapy alone (n = 6) (17.0 vs 8.1 months). However, the median survival time was similar (29.6 vs 27.4 months). Local recurrence was observed in 5 patients treated with chemotherapy alone, whereas in 2 patients among 4 patients treated with reirradiation and chemotherapy. None of the patients developed radiation necrosis. In one case, the primary tumor was diffuse astrocytoma with IDH2 mutant, and the secondary tumor was glioblastoma with IDH 1/2 wild-type. Based on the difference of IDH2 mutation status, the secondary tumor with IDH 1/2 wild-type was diagnosed as a de novo tumor that was related to the previous radiation therapy.

Conclusions

RIG can occur beyond 20 years after successfully treating the primary disease using radiotherapy; thus, cancer survivors should be informed of the long-term risk of developing RIG and the need for timely neuroimaging evaluation. Reirradiation combined with chemotherapy appears to be feasible and has favorable outcomes. Determining the IDH1/2 mutational status is useful to establish RIG diagnosis when the primary tumor is glioma.

STMO-17 Treatment outcome of photodynamic therapy using talaporfin sodium for recurrent high-grade glioma

Objective: Photodynamic therapy (PDT) using Talaporfin Sodium (TS) is a novel therapeutic strategy to improve local tumor control in high-grade glioma. TS is a photosensitizer that accumulates in tumor cells and produces highly toxic free radicals by intraoperative irradiation of laser with a 664nm wavelength. However, little is known about the treatment outcomes of PDT in recurrent high-grade gliomas (rHGG). In this study, we investigated the treatment outcome of PDT in rHGG and evaluated the correlation between intratumoral TS accumulation and outcomes. Methods: We included 21 patients with rHGG and 22 tumors, who were treated by PDT between June 2016 and March 2021. TS was transvenously administered 22–26 hours before PDT. Intratumoral TS concentrations were measured by liquid chromatography using frozen tissue. Results: The rHGGs included 10 glioblastoma, IDH1/2-wildtype (GBM, IDH1/2-WT: 45.5%), 3 GBM, IDH1/2-mutant (GBM, IDH1/2-Mut: 13.6%), 7 anaplastic oligodendroglioma, IDH1/2-Mut/codel (AO, IDH1/2-Mut/codel: 31.8%), 1 anaplastic astrocytoma, IDH1/2-WT (AA, IDH1/2-WT: 4.5%), 1 high-grade astrocytoma, IDH1/2-WT (4.5%). The median local progression free survival (PFS) time after PDT was 3.6 months and the median survival time from PDT was 19.4 months. The intratumoral TS concentrations of 7 tumors (TS(-): 31.8%) were below the limit of quantification, and the intratumoral TS concentrations of the remaining 15 tumors (TS(+)) were 43.5 ng/mg-protein (14.7–132 ng/mg-protein). The intratumoral TS concentrations were not significantly associated with IDH1/2 mutation status, cellularity, tumor grade, and pattern of enhancement. The median PFS from PDT tended to be longer in TS(+) than in TS(-) (TS(+): 6.3 vs TS(-): 1.4 months, p = 0.054). Conclusions: We found that the intratumoral TS concentrations were heterogeneous and 31.8% were below the limit of quantification. TS(+) tended to have better local tumor control than TS(-), suggesting the intratumoral TS accumulation have an impact of treatment outcomes of PDT.

RT-5 Boron Neutron Capture Therapy has extended progression-free survival about recurrent malignant peripheral nerve sheath tumor - A case report

Introduction: Recurrent malignant peripheral nerve sheath tumor (MPNST) is intractable. Boron neutron capture therapy (BNCT) is a treatment using tumor-selective particle radiation, and is indicated for medical treatment for head and neck cancer, and also used for malignant glioma and malignant meningioma.<Case>20-year-old woman who has MPNST that extends from the subcutaneous tissue of the right neck to the posterior fossa. <Medical History>Chemotherapy and local irradiation(50.4Gy/28fr) for primary embryonal rhabdomyosarcoma of the right ear canal at the age six.<Current medical history>Right cervical tumor developed at 17-year-old, some chemotherapy regimens and tumor resections were performed as recurrence of rhabdomyosarcoma at the previous hospital. After she was diagnosed with MPNST in the pathology consultation at our hospital, she was irradiated with heavy ion beam 70.8Gy(RBE)/16fr and received additional chemotherapies at our department, but her tumor was refractory. Although BNCT for MPNST is not covered by health insurance in Japan, she wanted to try to be treated for BNCT. After confirming boron accumulation in the tumor (SUVmax 4.28) by FBPA-PET, tumor growth and hydrocephalus occurred while waiting for travel to Taiwan due to the spread of COVID-19 infection. She was performed tumor resection(NTR) and irradiated with SRS 20Gy/fr for the residual lesion, but tumor had a rapid recurrence from the margin of the excision cavity. Finally, she could travel about 3 months after the operation and underwent BNCT, that used neutrons and 10B-boronophenylalanine from the Tsinghua University research reactor in Taiwan. No serious adverse events including cerebral edema were observed, and dramatic tumor shrinkage was maintained after treatment. FBPA-PET of 3 months later showed accumulation in the part of the margin of the cavity, the recurrence was observed on MRI after 3 and a half months. Discussion: BNCT for refractory/recurrent MPNST showed acceptable safety and was able to prolong progression-free survival.

MPC-1 DNA methylome analysis suggested the presence of “true” IDH-wildtype lower-grade gliomas

Background: There will be significant changes in the diagnosis of IDH-wildtype adult-type gliomas in the upcoming 5th edition of the WHO Classification of Central Nervous System Tumours. IDH-wildtype lower grade gliomas (IDHwt LGGs) that harbor molecular features of glioblastoma (EGFR amplification, the combination of whole chromosome 7 gain and whole chromosome 10 loss (7+/10-), or TERT promoter mutations) will be diagnosed as glioblastomas (GBMs), while IDH-wildtype astrocytomas will not be included as a separate tumor type. However, IDHwt LGGs are a very heterogeneous group of tumors, and further investigation is warranted particularly in those without molecular features of glioblastoma. To elucidate the biology of IDHwt LGGs, we analyzed DNA methylation profile and survival time. Materials and Methods: Of the 724 adult-type diffuse glioma samples from a multi-institutional study, 64 IDHwt LGG, including 54 without any of molecular features of GBM and 10 with PDGFRA amplification or TERT promoter mutation, were examined using Infinium MethylationEPIC BeadChip. The raw data files (IDAT files) were analyzed by the web-based DNA methylation classifier provided by DKFZ (MolecularNeuropathology.org) or by R (Version 4.0.4) using the minfi (1.34.0) and Rtsne (0.15) packages. [Result] Twenty-three out of 54 IDHwt LGGs matched known methylation classes using the DKFZ methylation classifier. In t-Distributed Stochastic Neighbor Embedding clustering analysis, 20 cases formed a cluster within the methylation class family glioblastoma, IDH-wildtype, mainly subclass RTK I (“GBM” cluster). Another 29 IDHwt LGGs formed an independent cluster (“LGG” cluster) separate from any of the existing reference groups near but not overlapping with several subtypes of pediatric-type lower grade gliomas. The “LGG” cluster cases had significantly longer overall survival than the “GBM” cluster cases. Discussion: Methylation profiling showed that IDHwt LGGs without molecular features of GBM were heterogeneous group of tumors. Our data suggested the presence of “true” IDHwt LGGs with intermediate prognosis.

ACT-6 Clinical manifestations of the patients with relapsed glioblastoma after bevacizumab treatment

Introduction:The outcome of glioblastoma (GBM) is improving recently, but still only temozolomide and bevacizumab (BEV) are recognized as the effective agents that are reimbursed in Japan. On large clinical trials, BEV prolonged progression free survival (PFS) but the remaining survival period from the relapse after BEV is only 3–5 month. On this study, we retrospectively analyzed the data of GBM patients who were treated with BEV to explore the best usage of BEV.Methods:230 patients were diagnosed as GBM and received BEV from July 2013 to March 2021 in our institution. Among them, 104 patient, whose clinical courses were followed, were included in this study. (M:F=59:45, median age was 65.5) Results:The patients were divided into three groups by when they used BEV; upfront group at first line therapy, 1st relapse group at second line, and 2nd+ relapse group at more than third line. There were 42, 35, 27 patients in each group. The median overall survival (OS) was 17.6, 24.7, 46.1 month (p<0.0001), median PFS after BEV treatment (PFSpBEV) was 8.8, 5.1, 5.0 month (p=0.2532), and the median survival after BEV treatment (OSpBEV) was 15.0, 9.9, 9.2 month (p=0.4437), respectively. There were 64 patients (22, 25, 17 in each group) who reached progressive disease (PD) after BEV. The median survival after PD (OSpBEVpPD) was 4.5, 5.8, 4.3 month (p=0.1590), respectively.Discussion:At the first onset, we use BEV only when the patients have low PS. Our results showed that OS was significantly longer when BEV was used in the later stage, but there was no significant difference in OS or PFS after BEV treatment. Especially OSpBEVpPD was 4–6 month regardless of the timing of BEV. To improve the treatment outcome of GBM, breakthrough therapy is needed in addition to optimizing the usage of BEV.

Tissue 2-Hydroxyglutarate and Preoperative Seizures in Patients With Diffuse Gliomas

BACKGROUND AND OBJECTIVES

Mutant isocitrate dehydrogenase (IDH) 1/2 gene products gain a new ability to produce D-2-hydroxyglutarate (D2HG). IDH1/2 mutations are thought to be associated with seizures owing to the structural similarity between D2HG and glutamate. However, the effects of D2HG on seizures in clinical settings are not fully understood. We sought to investigate the relationship between tissue 2-hydroxyglutarate (2HG) concentration and preoperative seizures using clinical samples.

METHODS

We included 104 consecutive patients with diffuse glioma who underwent surgery from August 2008 to May 2016 and whose clinical presentation and IDH1/2 status were identified. The presence of preoperative seizures, tumor location, histopathologic diagnosis, IDH1/2 status, and 1p/19q codeletion were assessed from the patient charts. Tissue 2HG concentration was measured using liquid chromatography-tandem mass spectrometry. To evaluate 2HG distribution without artefactual tissue disruption, we applied matrix-assisted laser desorption/ionization high-resolution mass spectrometry imaging (MALDI-MSI) in 12 patients' surgically resected samples. We assessed the correlation of preoperative seizures with tissue 2HG concentration, IDH1/2 status, WHO grade, and 1p/19q codeletion.

RESULTS

Tissue 2HG concentration was higher in IDH1/2 mutant tumors (IDH-Mut, n = 42) than in IDH1/2 wild-type tumors (IDH-WT, n = 62) (median 4,860 ng/mg vs 75 ng/mg) (p < 0.0001). MALDI-MSI could detect 2HG signals in IDH-Mut, but not in IDH-WT. Preoperative seizures were observed in 64.3% of patients with IDH-Mut and 21.0% patients with IDH-WT (p < 0.0001). The optimal cutoff value of tissue 2HG concentration for predicting preoperative seizures was 1,190 ng/mg, as calculated by the receiver operating characteristic curve. Increased preoperative seizure risk was only observed in tumors with 2HG concentration above the cutoff value among IDH-Mut (IDH-Mut with above the cutoff value: 71.4% vs IDH-Mut with below the cutoff value: 28.6%; p = 0.031). Multivariate analysis, including IDH1/2 mutation status, tissue 2HG concentration, WHO grade, and 1p/19q codeletion, revealed that only increased tissue 2HG concentration was associated with preoperative seizures (odds ratio 5.86, 95% confidence interval 1.02-48.5; p = 0.048).

DISCUSSION

We showed that high tissue 2HG concentration was associated with preoperative seizures, suggesting that excess 2HG increases risk of preoperative seizures in IDH1/2 mutant tumors.

TERT promoter mutation status is necessary and sufficient to diagnose IDH-wildtype diffuse astrocytic glioma with molecular features of glioblastoma

The Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy (cIMPACT-NOW) update 3 recommends that histologic grade II and III IDH-wildtype diffuse astrocytic gliomas that harbor EGFR amplification, the combination of whole chromosome 7 gain and whole chromosome 10 loss (7 + /10 -), or TERT promoter (pTERT) mutations should be considered as glioblastomas (GBM), World Health Organization grade IV. In this retrospective study, we examined the utility of molecular classification based on pTERT status and copy-number alterations (CNAs) in IDH-wildtype lower grade gliomas (LGGs, grade II, and III). The impact on survival was evaluated for the pTERT mutation and CNAs, including EGFR gain/amplification, PTEN loss, CDKN2A homozygous deletion, and PDGFRA gain/amplification. We analyzed 46 patients with IDH-wildtype/pTERT-mutant (mut) LGGs and 85 with IDH-wildtype/pTERT-wildtype LGGs. EGFR amplification and a combination of EGFR gain and PTEN loss (EGFR + /PTEN -) were significantly more frequent in pTERT-mut patients (p < 0.0001). Cox regression analysis showed that the pTERT mutation was a significant predictor of poor prognosis (hazard ratio [HR] 2.79, 95% confidence interval [CI] 1.55-4.89, p = 0.0008), but neither EGFR amplification nor EGFR + /PTEN - was an independent prognostic factor in IDH-wildtype LGGs. PDGFRA gain/amplification was a significant poor prognostic factor in IDH-wildtype/pTERT-wildtype LGGs (HR 2.44, 95% CI 1.09-5.27, p = 0.03, Cox regression analysis). The IDH-wildtype LGGs with either pTERT-mut or PDGFRA amplification were mostly clustered with GBM by DNA methylation analysis. Thus, our study suggests that analysis of pTERT mutation status is necessary and sufficient to diagnose IDH-wildtype diffuse astrocytic gliomas with molecular features of glioblastoma. The PDGFRA status may help further delineate IDH-wildtype/pTERT-wildtype LGGs. Methylation profiling showed that IDH-wildtype LGGs without molecular features of GBM were a heterogeneous group of tumors. Some of them did not fall into existing categories and had significantly better prognoses than those clustered with GBM.

Outcomes of salvage fractionated re-irradiation combined with bevacizumab for recurrent high-grade gliomas that progressed after bevacizumab treatment*

BACKGROUND

There is no standard treatment for patients with recurrent high-grade gliomas who progress after bevacizumab treatment. We evaluated the outcomes of re-irradiation combined with bevacizumab for patients refractory to bevacizumab.

METHODS

Between January 2015 and September 2019, patients with progression after bevacizumab treatment were treated with re-irradiation combined with bevacizumab (25 Gy in five fractions).

RESULTS

Fourteen patients [glioblastoma, isocitrate dehydrogenase (IDH) wild type (N = 6), glioblastoma, IDH mutant (N = 4), anaplastic astrocytoma, IDH wild type (N = 1), anaplastic astrocytoma, IDH mutant (N = 1), glioblastoma, not otherwise specified (N = 1) and radiologically diagnosed brainstem glioma (N = 1)] were included in this study. The median survival and progression-free survival times after re-irradiation combined with bevacizumab were 6.1 and 3.8 months, respectively. The 6-month survival and progression-free survival rates were 54.5 and 15.7%, respectively. Patients with a Karnofsky performance status of ≥70 tended to have longer median survival time (9.3 vs. 5.4 months, respectively; P = 0.058) and had a significantly longer median progression-free survival time (4.2 vs. 3.7 months, respectively; P = 0.046) than those with a Karnofsky performance status of <70. Four patients (28.6%) achieved a complete or partial radiological response, and three patients (21.4%) had an improved Karnofsky performance status after re-irradiation combined with bevacizumab. Grade 3/4 toxicities included leukopenia in four patients (28.6%), hypertension in three (21.4%), proteinuria in one (7.1%) and gastrointestinal hemorrhage in one (7.1%).

CONCLUSIONS

Re-irradiation combined with bevacizumab for patients with recurrent high-grade gliomas who progress after bevacizumab treatment was feasible. Re-irradiation combined with bevacizumab is a potential treatment option, especially for patients with a Karnofsky performance status of ≥70.

Utility of methylthioadenosine phosphorylase immunohistochemical deficiency as a surrogate for CDKN2A homozygous deletion in the assessment of adult-type infiltrating astrocytoma

Homozygous deletion (HD) of CDKN2A is one of the most promising biomarkers for predicting poor prognosis of IDH-mutant diffuse gliomas. The Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy (cIMPACT-NOW) recommendations propose that IDH-mutant lower-grade astrocytomas with CDKN2A/B HD be classified as grade IV tumors. Loss of methylthioadenosine phosphorylase (MTAP) immunohistochemistry staining has been proposed as a surrogate of CDKN2A HD in various tumors but its performance has not been fully investigated in diffuse glioma. This study determined whether MTAP immunoreactivity could serve as a proxy for CDKN2A HD in adult-type diffuse glioma, thereby contributing to stratifying patient outcome. MTAP immunohistochemistry staining using clone EPR6893 was scored in 178 diffuse glioma specimens consisting of 77 IDH-mutant astrocytomas, 13 IDH-mutant oligodendrogliomas, and 88 IDH-wildtype glioblastomas. The use of MTAP immunohistochemical deficiency to predict CDKN2A HD was good for IDH-mutant astrocytomas (sensitivity, 88%; specificity, 98%) and IDH-wildtype glioblastomas (sensitivity, 89%; specificity, 100%), but poor for IDH-mutant oligodendrogliomas (sensitivity, 67%; specificity, 57%). Both CDKN2A HD and MTAP immunohistochemical deficiency were significant adverse prognostic factors of overall survival for IDH-mutant astrocytoma (P < 0.001 each), but neither were prognostically significant for oligodendroglioma or IDH-wildtype glioblastoma. IDH-mutant lower-grade astrocytoma with CDKN2A HD and deficient MTAP immunoreactivity exhibited overlapping unfavorable outcome with IDH-mutant glioblastoma. MTAP immunostaining was easily interpreted in 61% of the cases tested, but scoring required greater care in the remaining cases. An alternative MTAP antibody clone (2G4) produced identical scoring results in all but 1 case, and a slightly larger proportion (66%) of cases were considered easy to interpret compared to using EPR6893. In summary, loss of MTAP immunoreactivity could serve as a reasonable predictive surrogate for CDKN2A HD in IDH-mutant astrocytomas and IDH-wildtype glioblastomas and could provide significant prognostic value for IDH-mutant astrocytoma, comparable to CDKN2A HD.

HGG-39. CLINICAL CHARACTERISTICS AND OUTCOME OF PATIENTS WITH RADIATION-INDUCED GLIOMA

The development of gliomas subsequent to therapeutic cranial irradiation is a rare but serious complication. The purpose of this study is to understand the clinical characteristics and outcome of patients with radiation-induced glioma (RIG). Between 2001 and 2018, we identified 10 patients with RIG, which satisfied the Cahan’s criteria in our data base. There was no sex predominance (M: 5, F: 5), and the median age of the primary diseased was 13.5 years (range: 1–39). The primary diseases included 2 germinoma, 2 acute lymphoblastic lymphoma, 2 medulloblastoma, 1 diffuse astrocytoma, 1 pilocytic astrocytoma, 1 pituitary adenoma and 1 metastatic tumor from lung cancer. All the patients received cranial radiation (range: 12–60 Gy). The median latency time between primary disease and RIG was 16 years (range: 9–30 years), which was not correlated with age at the time of primary disease (r2= 0.014, p=0.74). Radiation-induced gliomas included 8 glioblastoma and 2 grade III glioma based on histological diagnosis. After surgical removal or biopsy of the RIG, 4 patients underwent chemotherapy alone (nimustine, temozolomide (TMZ), carboplatin and etoposide), and 6 received chemotherapy (nimustine, TMZ, bevacizumab) combined with radiotherapy (range: 40-66Gy). The median progression free survival and survival time from RIG were 10.1 and 27.5 months, respectively. In summary, RIG may occur many years after successful initial treatment using radiotherapy, and the outcome of our patients with RIG supports the use of radiotherapy and/or chemotherapy after surgical resection.

GCT-62. DISSECTING INTRATUMORAL HETEROGENEITY OF CENTRAL NERVOUS SYSTEM GERM CELL TUMORS BY SINGLE-CELL RNA-SEQUENCING

BACKGROUND

Central nervous system germ cell tumor (CNSGCT) is a rare pediatric brain tumor. However, they are found at a relatively high incidence in East Asia. Germinoma is sensitive toward radiotherapy and chemotherapy; however, non-germinoma GCTs (NGGCT) often show poor response. Some cases are a mixture of germinoma and NGGCT (mixed GCT), and they sometimes change histological subtypes at recurrence. Previous report demonstrated that a germinoma and NGGCT component within the same mixed GCT tissue shared the same gene mutation, whereas the genome-wide methylation profiles were distinct from each other. The methylation profiles of germinoma was similar to the primordial germ cells (PGC) at the migration phase, supporting a model that PGC is the cell of origin for CNSGCT. However, tumor heterogeneity hinder information of the mixed bulk RNA-sequence data, causing difficulty in elucidating the mechanism of tumor development. The purpose of this study was to investigate the tumor cells subpopulations at the resolution of individual cells by single-cell RNA-seq.

RESULTS

Fresh surgical tumor tissue was immediately dissociated mechanically and enzymatically. Tumor cells are separated from CD45-labelled lymphocytes by FACS, and libraries were generated by Chromium Single cell 3’ Reagent Kit. Total of 11 tumor samples were collected and sequenced. Unsupervised Clustering showed individual clusters. One of the clusters had high expression of Oct-4, which is a marker of germinoma. The other clusters showed different subtypes of cells representing the heterogeneity of CNSGCT. Further analysis including a pseudo-time course analysis is underway to identify the lineage of tumor cell development.

TERT promoter mutation confers favorable prognosis regardless of 1p/19q status in adult diffuse gliomas with IDH1/2 mutations

TERT promoter mutations are commonly associated with 1p/19q codeletion in IDH-mutated gliomas. However, whether these mutations have an impact on patient survival independent of 1p/19q codeletion is unknown. In this study, we investigated the impact of TERT promoter mutations on survival in IDH-mutated glioma cases. Detailed clinical information and molecular status data were collected for a cohort of 560 adult patients with IDH-mutated gliomas. Among these patients, 279 had both TERT promoter mutation and 1p/19q codeletion, while 30 had either TERT promoter mutation (n = 24) or 1p/19q codeletion (n = 6) alone. A univariable Cox proportional hazard analysis for survival using clinical and genetic factors indicated that a Karnofsky performance status score (KPS) of 90 or 100, WHO grade II or III, TERT promoter mutation, 1p/19q codeletion, radiation therapy, and extent of resection (90-100%) were associated with favorable prognosis (p < 0.05). A multivariable Cox regression model revealed that TERT promoter mutation had a significantly favorable prognostic impact (hazard ratio = 0.421, p = 0.049), while 1p/19q codeletion did not have a significant impact (hazard ratio = 0.648, p = 0.349). Analyses incorporating patient clinical and genetic information were further conducted to identify subgroups showing the favorable prognostic impact of TERT promoter mutation. Among the grade II-III glioma patients with a KPS score of 90 or 100, those with IDH-TERT co-mutation and intact 1p/19q (n = 17) showed significantly longer survival than those with IDH mutation, wild-type TERT, and intact 1p/19q (n = 185) (5-year overall survival, 94% and 77%, respectively; p = 0.032). Our results demonstrate that TERT promoter mutation predicts favorable prognosis independent of 1p/19q codeletion in IDH-mutated gliomas. Combined with its adverse effect on survival among IDH-wild glioma cases, the bivalent prognostic impact of TERT promoter mutation may help further refine the molecular diagnosis and prognostication of diffuse gliomas.

Highly sensitive detection of TERT promoter mutations in recurrent glioblastomas using digital PCR

Telomerase reverse transcriptase promoter (TERTp) hotspot mutations are the most frequent mutations in primary glioblastomas (GBM). Previous studies have shown that the combination of TERTp and isocitrate dehydrogenase (IDH) status may serve as a useful diagnostic marker for oligodendroglioma and glioblastoma. In oligodendrogliomas, TERTp and IDH mutations, along with the 1p/19q codeletion, usually coexist and are likely to be founder mutations. However, in contrast to oligodendroglioma, the role of the TERTp status in GBM remains obscure. Here, we used Sanger sequencing, pyrosequencing, and digital PCR (dPCR) to examine the TERTp status in 15 pairs of frozen tissue samples from primary and recurrent IDH wild-type GBM, all of which were operated in a single institute. We showed that the TERTp status was stable between primary and recurrent GBM but this consistency was only detected by dPCR. The results suggest that dPCR is a powerful, highly sensitive tool to detect TERTp mutations, especially in a mixed cell population (e.g., a recurrent GBM tissue) where earlier treatment may have grossly altered the tumor microenvironment.

Resection of carcinoma of the external auditory canal in a patient with a high jugular bulb using temporal craniotomy

External auditory canal (EAC) carcinoma is a rare and unusual malignancy. The complex anatomy and relationship between the tumor and surrounding tissues in a limited space render it difficult to attain safe resection margins during surgery. A high jugular bulb (HJB) is one such anatomical variation that has important surgical implications that complicate the surgical procedure for EAC carcinoma. A 73-year-old woman presented with a 3-month history of right ear pain. Pathological findings and computed tomography (CT) revealed EAC carcinoma, which was expanding to the middle ear (ME). Although there was no cavity inside the ME, an HJB was detected. Surgical treatment using a temporal incision for temporal craniotomy achieved complete resection of the tumor and preserved facial nerve function. The patient recovered without complications and was discharged 17 days after the operation. Temporal incision and temporal craniotomy is a useful approach for EAC carcinoma with HJB.

Usefulness of carbon-11-labeled methionine positron-emission tomography for assessing the treatment response of primary central nervous system lymphoma

BACKGROUND

Primary central nervous system lymphoma (PCNSL) responds relatively quickly to chemotherapy or radiotherapy. However, determination of a complete response after treatment is often difficult because of extremely light residual contrast enhancement on magnetic resonance images due to the effects of microhemorrhages and scar tissue formation. These small enhancing lesions define an unconfirmed complete response. The aim of this study was to investigate the usefulness of carbon-11-labeled methionine (11C-Met) positron-emission tomography (PET) for determining the treatment response of PCNSL.

METHODS

Data for 36 patients who were treated for PCNSL between 2011 and 2015 and underwent magnetic resonance imaging and 11C-Met PET were reviewed. Magnetic resonance imaging findings were classified as complete response, unconfirmed complete response, and tumor mass (a composite of partial response, stable disease and progressive disease). PET images were evaluated, standardized uptake values were quantified, and the tumor-to-normal tissue count ratio (TNR) was calculated. Receiver operating characteristic curves were generated to determine the optimal cutoff TNRs.

RESULTS

The optimal TNRs for differentiating complete response and unconfirmed complete response from tumor mass were 1.83 (area under the curve, 0.951) and 1.80 (area under the curve, 0.932), respectively. The corresponding sensitivity and specificity values for the diagnosis of tumor mass were 82.4 and 100%, respectively, in the complete response group and 85.3 and 85%, respectively, in the unconfirmed complete response group.

CONCLUSIONS

A TNR of ≥1.80 can aid in the detection of active PCNSL using 11C-Met PET. Thus, 11C-Met-PET may be a useful tool for accurate evaluation of the treatment efficacy in PCNSL.

Risk Factors for Delayed Surgical Recovery and Massive Bleeding in Skull Base Surgery

BACKGROUND

To determine factors that delay surgical recovery and increase intraoperative hemorrhage in skull base surgery.

METHODS

Factors related to delayed postoperative recovery were retrospectively reviewed in 33 patients who underwent open skull base surgery. Early and late recovery phases were assessed as "days required to walk around the ward (DWW)" and "length of hospital stay (LHS)," respectively. Intraoperative blood loss was cal-culated every hour and analyzed in 4 steps, i.e., craniotomy and intracranial manipulation, cranial fossa osteotomy, extracranial osteotomy, and reconstruction.

RESULTS

More than 4,000 mL of blood loss (B = 2.7392, Exp[B] = 15.4744; 95% CI 1.1828-202.4417) and comorbidi-ty (B = 2.3978, Exp[B]) = 10.9987; 95% CI 1.3534-98.3810) significantly prolonged the DWW; the occurrence of postoperative complications significantly delayed the LHS (p = 0.0316). Tumor invasion to the hard palate, the maxillary sinus, the pterygopalatine fossa, the base of the pterygoid process, the sphenoid sinus, the middle cranial fossa, and the cavernous sinus and a long operation time (>13 h) were associated with increased total hemorrhage. The optimal cut-off hemorrhage volume associated with total massive blood loss in craniotomy and intracranial manipulation (AUC = 0.8364), cranial fossa osteotomy (AUC = 0.8000), and extracranial osteotomy (AUC = 0.8545) was 1,111, 750, and 913 mL, respectively. Persistent infection (6%) and neuropsychiatric disorder (6%) are direct causes of delayed LHS.

CONCLUSION

Blood loss, comorbidity, and postoperative complications were risk factors for delayed surgical recovery. Meticulous preoperative planning, intraoperative surefire hemostasis, and perioperative holistic management are prerequisites for safe skull base surgery.

First case of human neurocoenurosis caused by Taenia serialis: A case report

Human coenurosis is caused by the larval stages of Taenia species, mainly Taenia multiceps and Taenia serialis. T. multiceps has been reported to cause human central nervous system (CNS) infections, but no CNS case caused by T. serialis has been reported. The authors report the first case of human neurocoenurosis caused by T. serialis, which was confirmed by mitochondrial DNA analysis. A 38-year-old man presented with visual disturbance and headache, and subsequent magnetic resonance imaging (MRI) revealed a ring-enhancing cystic lesion in the left occipital lobe. Biopsy was performed, and the resultant histopathological diagnosis was that of low-grade B-cell lymphoma. Chemotherapy was initiated, but a subsequent MRI showed increased ring enhancement. Due to the unexpected clinical course, a surgical resection of the lesion was performed. The lesion was completely removed. Pathological examination showed multiple scolices with hooklets, suckers, and numerous calcareous corpuscles. Therefore, the diagnosis of neurocysticercosis was made. However, mitochondrial DNA analysis showed that the disease was definitively coenurosis caused by T. serialis. Albendazole was administered, with no evidence of recurrence at 12 months following the operation. In this study, we demonstrate that T. serialis can cause CNS infection and that genetic analysis is recommended to establish a definitive diagnosis.

A rare case of brain metastasis from poorly differentiated small bowel adenocarcinoma

Background:

Small bowel adenocarcinoma (SBA) accounts for <2% of all gastrointestinal malignancies. The most common organs of SBA metastases are the abdominal lymph node, liver, and peritoneum. There have been almost no reports of brain metastases of SBA. Dabaja et al. reported 1 case of brain metastasis out of 217 SBA cases, but details of the clinical course of the case were unclear. Our case might be the first report covering the full clinical course, pathological findings, and genetic data. Here, we report a very rare case of brain metastasis from poorly differentiated SBA.

Case Description:

A 54-year-old man who suffered from abdominal pain and melena visited a nearby hospital. This patient had no risk factors for SBA. He underwent partial resection of the jejunum with regional lymphadenectomy and combined resection of the transverse colon. Pathological diagnosis was poorly differentiated adenocarcinoma, pT4N2M0 Stage IIIB (UICC-TNM: 8^th edition). One month after curative surgery, liver metastasis was detected by a computed tomography (CT) scan, and then, palliative chemotherapy was started. During the third-line chemotherapy, a brain tumor on the left cerebellum was detected by the CT scan. Tumor resection was performed, and the histopathological features coincided with the primary jejunum tumor. Based on surgical, radiological, pathological, and genetic findings, this brain tumor was comprehensively diagnosed as a metastasis from poorly differentiated SBA.

Conclusion:

Here, we experienced a very rare case of brain metastasis from poorly differentiated SBA.

NQPC-13 THE EFFICACY OF RAVEN’S COLORED PROGRESSIVE MATRICES FOR PATIENTS WITH BRAIN TUMOR

BACKGROUND

Mini-Mental State Examination (MMSE) and Raven’s Colored Progressive Matrices (RCPM) are cognitive function tests used to assess speech and visual cognitive functions in patients with brain tumor and aphasia, respectively. We investigated the distribution and correlation between MMSE and RCPM scores in patients with brain tumor, who underwent tumor resection, to identify the test characteristics.

METHOD

Among the 122 patients who underwent tumor resection in our hospital from April 2018 to March 2019, and potentially required rehabilitation, 43 patients (i.e., 19 men and 24 women) who underwent pre- and post-operative MMSE and RCPM were further investigated. Median age during surgery was 54 years (20–86 years). Relationship between the pre- and post-operative MMSE and RCPM scores were evaluated using the Spearman’s rank correlation coefficient. Additionally, we investigated the characteristics of patients who scored low on either of the tests.

RESULTS

Median pre- and post-operative MMSE scores were 29 points (14–30) and 29 points (21–30), respectively. Median pre- and post-operative RCPM scores were 33 points (25–36) and 35 points (18–36), respectively. The pre- and post-operative correlation coefficient between MMSE and RCPM scores were 0.376 and 0.699, respectively. Among the 12 patients with lower pre-operative scores on MMSE, as compared to RCPM, 8 patients had impaired attention and 4 patients had aphasia. One patient who scored lower on RCPM test, as compared to MMSE, had reduced analogical reasoning ability. Postoperatively, no patient scored low on MMSE as compared to RCPM, and one patient who scored lower on RCPM than MMSE had left hemi-spatial neglect.

CONCLUSION

The pre-operative cognitive functions of patients with impaired attention and aphasia can be evaluated with RCPM using visual tasks without interference caused by these impairments. Minute pre- and post-interventional cognitive changes can be assessed with both MMSE and RCPM together.

ACT-14 A FIRST-IN-HUMAN STUDY OF MUTANT IDH1 INHIBITOR DS-1001B IN PATIENTS WITH RECURRENT GLIOMAS

BACKGROUND

WHO grade II/III gliomas frequently harbor isocitrate dehydrogenase 1 (IDH1) mutations, resulting in intratumoral accumulation of oncometabolite D-2-hydroxyglutarate (D-2-HG) and subsequent clonal expansion. DS-1001b is an oral selective inhibitor of mutant IDH1 R132X that was designed to penetrate the blood-brain barrier.

METHODS

In this first-in-human, multicenter, phase I study (NCT03030066), eligible patients (pts) with recurrent/progressive IDH1 mutant glioma received DS-1001b twice daily (bid), continuous. A modified continual reassessment method was used for dose escalation. RANO and RANO-LGG criteria were used to assess tumor response. Pts who planned to undergo salvage surgery after developing progressive disease (PD) and who provided informed consent received DS-1001b treatment until surgery. Tumor samples were also obtained from those pts to measure the free form of DS-1001b and D-2-HG levels.

RESULTS

Between Jan 2017 and May 2019, DS-1001b (125–1400 mg bid) had administered for 47 pts, and 15 pts were continuing treatment. Maximum tolerated dose (MTD) was not reached. Most AEs were Gr 1–2. Gr 3 AEs were observed in 40% of pts. No Gr 4 or 5 AEs or serious drug-related AEs were reported. One dose limiting toxicity was Gr 3 white blood cell count decreased (1000 mg bid). Of 35 evaluable pts with contrast enhancing gliomas, one, five and 11 achieved complete response, partial response and stable disease (SD), respectively. Of evaluable 12 pts with contrast non-enhancing gliomas, four achieved minor response and eight achieved SD. Peak plasma concentration (Cmax) and area under the curve (AUC) increased dose-dependently.

CONCLUSIONS

DS-1001b was well tolerated up to 1400 mg bid with favorable brain distribution, and MTD was not reached. Recurrent/progressive IDH1 mutant glioma pts responded to treatment. Investigation is ongoing to determine the recommended Phase II dose. The latest data will be updated. Funding source: This study was funded by Daiichi Sankyo Co., Ltd.

MPC-11 IDH1/2 MUTATIONS ARE ASSOCIATED WITH SEIZURE ONSET AND VETRY IMAGING IN PATIENTS WITH DIFFUSE GLIOMA VISUALIZING 2-HYDROXYGLUTARATE BY MASS SPECTRUM

BACKGROUND

Mutations in isocitrate dehydrogenase 1 or 2 genes (IDH1/2) frequently occur in lower-grade gliomas. Mutant IDH1/2 proteins gain a new ability to produce 2-hydroxyglutarate (2HG). IDH1/2 mutations have shown to be related with seizure through the structural similarity of 2HG to glutamate. We, therefore, sought to investigate the relationship between seizure and IDH1/2 mutations and to visualize tissue 2HG distribution in patients with diffuse gliomas.

METHODS

We assessed 149 patients with diffuse glioma, and measured tissue 2HG concentrations in 104 patients by using liquid chromatography-tandem mass spectrometry. The matrix-assisted laser desorption/ionization high resolution mass spectrometry imaging (MALDI-HR-MSI) was used to visualize tissue 2HG distribution for 12 tissue samples.

RESULTS

Seizure onset was observed in 34 among 56 (60.7%) patients with IDH1/2 mutant tumor, whereas in 18 among 93 (19.4%) patients with IDH1/2 wild-type tumor (p<0.0001). The tissue 2HG concentration was significantly higher in IDH1/2 mutant tumor than in IDH1/2 wild-type tumor (median: 4862 ng/mg vs 75 ng/mg) (p<0.0001). Multivariate analysis, including tissue 2HG concentration, IDH1/2 status, histology, grade, and location, showed that IDH1/2 mutations was significantly correlated with seizure onset. The MALDI-HR-MSI showed that 2HG spread in various concentration independent of cellularity and also in extracellular space in IDH1/2 mutant tumor tissue.

CONCLUSIONS

We demonstrated the association between IDH1/2 mutations and seizure, and the heterogeneous 2HG distribution not only in cellular area but also in extracellular space. These findings suggest the potential role of 2HG as an intercellular mediator to tumor environment, resulting in epileptogenesis formation.

NQPC-14 COMPARISON OF QOL SCALES IN PATIENTS WITH BRAIN TUMORS

PURPOSE

Measurement of quality of life (QOL) of patients with brain tumors is a challenge, because parameters of the established QOL scales for cancer patients are easily affected by the focal neurological deficits. Thus, simpler QOL scales which are feasible for evaluation of QOL with severe neurological deficits are required. We compared the results of four QOL scales in patients with brain tumors.

METHODS

From 2015 to 2018, we prospectively performed EORTC QLQ-C30/BN20 (C30/BN20), KPS, EQ-5D and “Distress and Impact Thermometer (DIT)” every three months.

RESULTS

2150 QOL evaluations from 710 patients were analyzed. The median age was 54 years (range 14–97). 319 glioma, 93 meningioma, 165 brain metastases and 133 other brain tumors were included. Global health status of C30/BN20 strongly correlated with QOL scores calculated by EQ-5D and DIT; it also showed correlation with KPS (correlation coefficients: 0.632, -0.675, -0.622, 0.412, respectively (p<0.001)). Most items of C30/BN20 showed relatively strong correlation with QOL scores, whereas KPS strongly correlated to physical activities and DIT strongly correlated to items related to psychological status. Seizures did not corelate with any other QOL scales. In patients with KPS≤60, wide dispersion of QOL scores and DIT were observed. In these patients, KPS correlated only with items 1–3 of EQ-5D and DIT with item 5. When time course of QOL scores in malignant glioma was evaluated, it was maintained until first remission, and significantly impaired at recurrence, compared to onset (p=0.014).

CONCLUSION

QOL scores can be used as an alternative for C30/BN20, and QOL time course of glioma can be adequately evaluated with it. KPS and DIT can also be alternative scales. These two scales should desirably be used in combination in patients with low KPS. Evaluations of feasibility and validity of these QOL scales in patients who cannot answer C30/BN20 are warranted.

COT-04 FAMILY SUPPORT FOR PATIENTS WITH PRIMARY MALIGNANT BRAIN TUMORS BY PATIENT SUPPORT GROUP IN NATIONAL CANCER CENTER

BACKGROUND

A family support group for patients with primary malignant brain tumors in our hospital is called “Brain Tumor Family Table.” We conduct regular meetings, such as 30 minutes of medical lectures and 60 minutes of healthcare discussions, between participants and medical staff which is supervised by a nurse. To provide more effective family support, we report our activities.

METHOD

A total of 96 family members participated in 11 meetings from July 2015 to March 2019 and answered anonymous questionnaires about their participation. This survey evaluated their motivation for participation and the level of satisfaction toward the lectures and discussions by three-level scores and free description.

RESULT

Regarding the reason of their participation, 28.1% of the participants answered, “I want to talk to someone who is in the same condition.” We found that 83.3% of them were satisfied with the lectures, and 89.6% of them were satisfied with the discussions and conversations. The reasons for their satisfaction were: “I was happy to hear the story of other patients” (19.0%), “I feel positive toward patient care” (19.0%), and “I realized I was not alone” (17.2%). Moreover, 92.7% answered “I would like to participate in the next meeting.” Among them, 26.1% answered “I want to talk again,” 14.2% answered “I feel stable,” and 14.2% answered “I can get information.” There were other opinions, like “Sharing feelings is important” and “I would like to help others next time,” as well.

DISCUSSION

Malignant brain tumors are orphan cancers, and patients and their families lack the information about the disease and the chance to share their experiences. Hence, participants were quite satisfied with this meeting. We will improve our facilitating skills as an organizing body so that participants can share their experiences and feelings to reduce their loneliness and finally feel positive toward patient care.

NQPC-10 END-OF-LIFE PHASE OF GLIOBLASTOMA

BACKGROUND

Despite aggressive treatment with surgery and chemo-radiation therapy, it is difficult to cure patients with glioblastoma (GBM). The end-of-life (EOL) phase of patients with GBM, and related problems, have not yet been adequately studied. Most cancer patients died in the hospital (84%) in 2017, but the Japanese government has recommended palliative home-care and the number of deaths at home has recently been increasing. This study explores the current situation of EOL care for GBM patients in our hospital.

METHODS

We retrospectively examined the clinical course and EOL phase of 166 consecutive patients who were treated in our hospital between 2010 and 2017.

RESULT

In total, 107 patients died; 28 (26%) at home, 25 (23%) in hospice care, 9(9%) in nursing homes, 21(20%) in long-term care hospitals (LTCH), 13(12%) in our hospital, and 11(10%) in other neurosurgical hospitals. The median survival time and length of EOL phase for patients who died at home were 596 and 77 days; 469 and 103 days in hospice care; 528 days and 149 days in LTCH; 388 days and 52 days in our hospital; 802 and 91 days in other neurosurgical hospital; and 565 days and 55 days in nursing homes, respectively. The KPS of patients who transferred to LTCH or was started palliative care in other neurological hospital was 60. That of other patients was 50.The patients who died at home entered deep coma in the last 3.5 days (n=24) of life and could not take oral feeds for 7 days (n=26).

CONCLUSION

According to cancer patient study, the home-based palliative time of longer prognosis group were 59 days. EOL phase of GBM may be longer than other cancer. We must consider the problems of the EOL phase and improve the quality of EOL care.

Assessment of the Diagnostic Utility of Serum MicroRNA Classification in Patients With Diffuse Glioma

IMPORTANCE

A blood-based screening tool for detecting diffuse glioma is necessary to improve clinical outcomes.

OBJECTIVES

To establish models using serum microRNAs to distinguish patients with diffuse glioma from control individuals without cancer (the Glioma Index) and to differentiate glioblastoma (GBM), primary central nervous system lymphoma (PCNSL), and metastatic brain tumors (the 3-Tumor Index).

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, case-control diagnostic study included 157 patients with diffuse glioma and 109 patients with central nervous system (CNS) diseases other than diffuse glioma diagnosed from August 1, 2008, through May 1, 2016, and 314 sex- and age-matched controls without cancer. Samples of patients with diffuse glioma and controls were randomly divided into training and validation set 1, and those of patients with CNS diseases other than diffuse glioma were allocated to an exploratory set. Samples of patients with GBM, PCNSL, and metastatic brain tumors were randomly divided into training and validation set 2. Data were analyzed from April 1, 2018, to March 31, 2019.

MAIN OUTCOMES AND MEASURES

The expression of 2565 microRNAs was assessed, and the diagnostic performance was evaluated by calculating the area under the receiver operating characteristics curve (AUC), sensitivity, specificity, and accuracy.

RESULTS

A total of 580 patients were included in the analysis (309 [53.3%] male; median age, 57 years [range, 10-87 years]). In training set 1, 100 patients with diffuse glioma (median age, 56 years [range, 14-87 years]; 55 male [55.0%]) were compared with 200 control patients (median age, 56 years [range, 14-87 years]; 105 male [52.5%]), and the Glioma Index was constructed using 3 microRNAs (miR-4763-3p, miR-1915-3p, and miR-3679-5p). In validation set 1, the AUC was 0.99 (95% CI, 0.99-1.00); sensitivity, 0.95 (95% CI, 0.89-1.00); and specificity, 0.97 (95% CI, 0.93-1.00). The Glioma Index classified 39 of 42 PCNSL samples (92.9%) and 25 of 28 metastatic brain tumor samples (89.3%) as positive and 2 of 2 spinal tumors (100%) as negative in the exploratory set. In training set 2, 68 patients with GBM, 34 with PCNSL, and 23 with metastatic brain tumor were compared, and the 3-Tumor Index was constructed using 48 microRNAs. The 3-Tumor Index had an accuracy of 0.80, positively detecting 16 of 17 GBM samples (94.1%), 4 of 5 metastatic brain tumor samples (80.0%), and 4 of 8 PCNSL samples (50.0%) in validation set 2.

CONCLUSIONS AND RELEVANCE

This study appears to have identified promising serum microRNA combinations for detecting diffuse glioma and for assessing histologic features of brain tumors.

Survival benefits of hypofractionated radiotherapy combined with temozolomide or temozolomide plus bevacizumab in elderly patients with glioblastoma aged ≥ 75 years

Background and purpose

The purpose of this study was to evaluate the outcomes of elderly patients (aged ≥75 years) with newly diagnosed glioblastoma (GBM), who were treated with hypofractionated radiotherapy comprising 45 Gy in 15 fractions combined with temozolomide (TMZ) or TMZ and bevacizumab (TMZ/Bev).

Materials and methods

Between October 2007 and August 2018, 30 patients with GBM aged ≥75 years were treated with hypofractionated radiotherapy consisting of 45 Gy in 15 fractions. Twenty patients received TMZ and 10 received TMZ/Bev as upfront chemotherapy. O-6-methylguanine DNA methyltransferase (MGMT) promoter methylation status was analyzed by pyrosequencing. The cutoff value of the mean level of methylation at the 16 CpG sites was 16%.

Results

Median overall survival (OS) and progression-free survival (PFS) were 12.9 months and 9.9 months, respectively. The 1-year OS and PFS rates were 64.7 and 34.7%, respectively. Median OS and PFS did not differ significantly between patients with MGMT promoter hypermethylation (N = 11) and those with hypomethylation (N = 16) (17.4 vs. 11.8 months, p = 0.32; and 13.1 vs. 7.3 months, p = 0.11, respectively). The median OS and PFS were not significantly different between TMZ (N = 20) and TMZ/Bev (N = 10) chemotherapy (median OS: TMZ 12.9 months vs. TMZ/Bev 14.6 months, p = 0.93, median PFS: TMZ 8.5 months vs TMZ/Bev 10.0 months, p = 0.64, respectively). The median time until Karnofsky performance status (KPS) score decreasing below 60 points was 7.9 months. The best radiological responses included 11 patients with a partial response (36.7%). Grade 3/4 toxicities included leukopenia in 15 patients (50%), anorexia in 4 (13.3%), and hyponatremia during concomitant chemotherapy in 3 (10%).

Conclusion

Our hypofractionated radiotherapy regimen combined with TMZ or TMZ/Bev showed benefits in terms of OS, PFS, and KPS maintenance with acceptable toxicities in elderly patients with GBM aged ≥75 years.