Non-invasively measured brain activity and radiological progression in diffuse glioma

Non-invasively measured brain activity is related to progression-free survival in glioma patients, suggesting its potential as a marker of glioma progression. We therefore assessed the relationship between brain activity and increasing tumor volumes on routine clinical magnetic resonance imaging (MRI) in glioma patients. Postoperative magnetoencephalography (MEG) was recorded in 45 diffuse glioma patients. Brain activity was estimated using three measures (absolute broadband power, offset and slope) calculated at three spatial levels: global average, averaged across the peritumoral areas, and averaged across the homologues of these peritumoral areas in the contralateral hemisphere. Tumors were segmented on MRI. Changes in tumor volume between the two scans surrounding the MEG were calculated and correlated with brain activity. Brain activity was compared between patient groups classified into having increasing or stable tumor volume. Results show that brain activity was significantly increased in the tumor hemisphere in general, and in peritumoral regions specifically. However, none of the measures and spatial levels of brain activity correlated with changes in tumor volume, nor did they differ between patients with increasing versus stable tumor volumes. Longitudinal studies in more homogeneous subgroups of glioma patients are necessary to further explore the clinical potential of non-invasively measured brain activity.

P14.13 Severe hematological toxicity during chemoradiation for glioblastoma: Identification of clinical and pharmacological risk factors and consequences for the individual patient

BACKGROUND

Besides early tumour progression, standard first-line radiation with concurrent and adjuvant temozolomide in de novo glioblastoma patients is abrogated frequently by severe haematological toxicity. This leads to treatment delays with unknown effect on efficacy and to more hospital visits with increased disease burden. In the present study, we identified clinical and pharmacological risk factors for temozolomide induced severe hematological toxicity. Furthermore, we describe the burden of toxicity for patients and evaluate the effect of severe toxicity on prognosis.

METHODS

A retrospective cohort study of adult patients with a histological confirmed glioblastoma (n=363), treated with standard treatment regimen at the Brain Tumor Center Amsterdam between 2000 and -2020. Severe haematological toxicity was defined as a CTCAE (version 5.0) grade ≥3. We used Pearson Chi-Square test to analyze differences in patient characteristics between the groups (no vs. severe toxicity) and paired samples T- Test to analyze fluctuations in cell counts. Univariate and multivariate logistic regression were used to identify patient- and treatment characteristics associated with severe hematological toxicity. Cox Proportional Hazards models were used to estimate Hazard Ratio’s for the association between survival and severe hematological toxicity.

RESULTS

Female gender (OR 8.05, 95%CI 2.96–21.89, p<0.001) and older age (age > 70 years; OR 2.44, 95%CI 1.12–5.31, p=0.025) were independent risk factors for severe toxicity. Concurrent and adjuvant temozolomide was discontinued in respectively 56% and 35% of the patients. In general, patients with severe hematological toxicity had a treatment delay of 22 ± 48 days. Of all patients with severe hematological toxicity during chemoradiation, 96% developed toxicity after ≥4 weeks of treatment (p<0.001). Females who received highest temozolomide-doses (4th quartile) had a longer survival than females with low cumulative temozolomide doses (1st quartile). Patients, who developed severe toxicity had much more hospital visits (20; range 12–26), and were admitted more frequently to the hospital. Severe haematological toxicity was not related to survival (HR 1.04; 95%CI 0.74–1.45).

CONCLUSION

Female gender and age >70 years are risk factors for severe hematological toxicity. Severe hematological toxicity relates to temozolomide exposure and results in a significant treatment burden for patients. Low temozolomide exposure results in decreased survival. Patient tailored therapy may result in better treatment outcomes.

P14.51 Can patients with a suspected high-grade glioma receive tumor treatment during pregnancy safely?

BACKGROUND

Diagnosis of a glioma during pregnancy has ethical and medical dilemmas; treatment of the mother may harm the unborn child, but a too conservative approach towards tumor treatment can compromise the survival of the mother. In patients with a suspected high-grade glioma, postponing tumor treatment is undesirable. We collected published cases to describe the given treatments during pregnancy and the outcomes for mother and child.

METHODS

From Pubmed, Embase and Web of Science, 122 cases were extracted from 65 reports published between 1999 and 2020. We added 7 cases from our center. Cases came from: North-America (54/129), Europe (47/129), Asia (13/129), Middle-East (3/129) and one from Oceania and Africa each; 10 cases were from an unspecified country. The data were analysed with descriptive statistics.

RESULTS

The median age of the pregnant women was 30 (range 17–48) years; at the time of publication 42% of mothers had deceased. Most frequent symptoms at presentation were high intracranial pressure (35%), seizures (30%) or focal deficits (19%). Patients were diagnosed in each phase of the pregnancy - 30% in the first, 35% in the second and 35% in the last trimester. Twenty-two women decided to terminate the pregnancy (North America 9; Europe 9; international unspecified, Africa, Asia and Middle-East each one case). In sixty-seven percent of women, tumors were operated while pregnant, 70% of those were planned surgery, while in 30% surgery was in performed in an emergency setting. Most women received a resection. In 6 patients tumor surgery was combined with a caesarian section. Histological diagnosis of the tumor was available in 112 patients: anaplastic oligodendroglioma (n=10), anaplastic astrocytoma (n=30), glioblastoma (n=66) or high-grade glioma NOS (n=6). In 10 patients there was a suspected high grade glioma based on MRI imaging. Only 20 patients were treated after surgery whilst still pregnant with either radiotherapy (15/20, 75%), chemotherapy (2/20, 10%) or a combination of radiotherapy and chemotherapy (3/20, 15%) Other patients received additional treatment after delivery (109/129; 84%). Delivery method was a caesarian section in 60% and vaginal delivery in 21%- in 19% delivery method was not described. In 63% of cesarean sections were brought forward either because of rapid maternal deterioration or to enable maternal treatment after delivery. In 92% a healthy child was born, 7% had a intrauterine fetal death and 1% the child was stillborn. None of the patients who experienced intrauterine fetal death had received radio- or chemotherapy during pregnancy.

CONCLUSIONS

The majority of pregnant women continue their pregnancy when facing a diagnosis of a high grade glioma. Tumor surgery seemed safe during pregnancy. No adverse events were reported in the limited patients who received radiotherapy (n=15) during pregnancy. For chemotherapy we could not draw any conclusions.

OS05.7.A Absence of severe hematological toxicity during first line treatment predicts low chance on severe toxicity during second line alkylating chemotherapy in glioblastoma

BACKGROUND

Glioblastoma has an infiltrative growth pattern that makes complete resection of the tumor virtually impossible. Sooner or later the tumor progresses, even after aggressive treatment with maximal safe resection, radiotherapy and/or chemotherapy. Hematological toxicity is an important cause of treatment delays during 1st line treatment. How often hematological toxicity occurs during 2nd line treatment is unclear. We explored rates of hematological toxicities in patients treated with temozolomide or lomustine at progression and investigated the association between severe toxicity during 1st and 2nd line treatment.

METHODS

We studied a retrospective cohort study of adult patients (n=247) with a glioblastoma treated with 2nd line alkylating chemotherapy at the Brain Tumor Center Amsterdam between 2000 and 2020. First line treatment of these patients consisted of a combination of radiotherapy combined with different treatments (80% received temozolomide, 4% PCV, 6% other chemotherapy and 10% radiotherapy only). Second line treatment consisted of temozolomide or lomustine. Mild and severe hematological toxicity were defined according to the CTCAE (version 5.0) criteria as a grade 1&2 and grade ≥3, respectively. We used descriptive statistics to analyze frequencies of hematological toxicity in patients with glioblastoma treated with 2nd line chemotherapy.

RESULTS

Sixty percent (147/247) of patients treated with 2nd line chemotherapy experienced hematological toxicity (grade 1–4). Considering subtypes of hematological toxicities, more patients experienced hematological toxicity during 2nd line treatment; severe thrombocytopenia occurred most frequently observed (6,1 during 1st line vs. 10,5% during 2nd line treatment), followed by neutropenia (3,6 vs. 6,9%), leukocytopenia (4,0 vs. 5,3%) and anemia (0 vs. 0,8%). Fewer patients treated with 2nd line temozolomide (n=113) experienced mild and severe hematological toxicity than patients treated with 2nd line lomustine (n=134; 46% versus 71% (for mild) and 12% vs 21% (severe toxicity), respectively). A subset of 107 patients was initially treated with radiotherapy and concurrent and adjuvant temozolomide; within this subset, patients with none or only mild toxicity during 1st line treatment had only a small risk of severe hematological toxicity during 2nd line treatment (4%). In contrast, the 34,5 % of patients with severe hematological toxicity during 1st line treatment also experienced severe hematological toxicity during 2nd line alkylating chemotherapy.

CONCLUSION

Hematological toxicity occurs more frequently during 2nd line treatment. Treatment with 2nd line temozolomide results in less hematological toxicity than lomustine. Absence of severe toxicity during 1st line treatment is predictive for the risk of toxicity during 2nd line treatment.

P12.02 Symptoms of patients with diffuse glioma during stable disease as a potential target for treatment

BACKGROUND

Patients with diffuse glioma experience many tumor- and treatment-related symptoms, including fatigue, cognitive deficits, and anxiety. It remains unclear how the frequency and burden of these symptoms change over time and specifically which symptoms patients experience during the stable phase of the disease. We assessed the frequency and burden of common symptoms in glioma patients during stable disease and whether patients were willing to undergo treatment for those symptoms. We suggest a top five of potentially treatable symptoms.

METHODS

Patients with a diffuse glioma during stable disease completed a questionnaire on symptoms they experienced during the past two weeks, such as irritability, fatigue, stress, pain, depressive thoughts and relationship problems. They rated the frequency and burden of seventeen symptoms on a seven-point numeric scale ranging from ‘never’ to ‘continuously’ and from ‘no burden’ to ‘unbearable’, respectively. Also, they stated whether they were willing to undergo treatment for each symptom. Data was collected retrospectively. The median values of the frequency and burden dimension were calculated for each symptom. We composed a top five of most frequent and burdensome symptoms. We used Kendall’s Tau to correlate frequency, burden and willingness to undergo treatment per symptom.

RESULTS

Fifty-two patients were included, 77% had a KPS score of 90–100, 23% a KPS score of 70–80 and 40% had a glioblastoma. The top five most frequent and burdensome symptoms were fatigue, memory problems, reduced physical fitness, concentration problems and drowsiness. Fatigue had the highest median value on the frequency (median 4.5, IQR 2.5) and burden (median 4.0, IQR 3.00) dimension and 21% of the patients were willing to undergo treatment for fatigue. Overall 35% of the patients were willing to undergo treatment for at least one symptom. Frequency and burden of symptoms correlated well (median Kendall’s Tau of 0.84 with a range of correlations of 0.73–0.95). Frequency and willingness to undergo treatment correlated less (median Kendall’s Tau of 0.35, range 0.24–0.57), as well as burden and willingness to undergo treatment (median Kendall’s Tau, range 0.28–0.61).

CONCLUSION

The top five symptoms most often reported by patients with diffuse glioma during stable disease were: fatigue, memory problems, reduced physical fitness, concentration problems and drowsiness. These symptoms may serve as a roadmap for future research on treatment strategies to alleviate these symptoms.

SUPPORT/DISCLOSURE

This project is funded by The Anita Veldman Foundation (CCA-2019-2-21).

P12.07 The potential of cannabinoids to improve quality of life in glioma patients: A meta-analysis in patients with neurological and oncological disease

BACKGROUND

Gliomas are primary brain tumors with a dismal prognosis. Reducing symptoms and maintaining quality of life (QoL) are main treatment aims in glioma patients. Mental well-being is an important subdomain of QoL. Cannabinoids have been suggested to alleviate frequently experienced symptoms of reduced mental well-being such as anxiety or depression. Glioma patients frequently report unprescribed cannabinoid use for these reasons. We performed a meta-analysis of the current evidence on cannabinoid efficacy on QoL and mental well-being to identify its added value in treatment of glioma patients.

MATERIAL AND METHODS

We performed a systematic PubMed, Embase and Web of Science search according to the PRISMA guidelines on September 22nd and 23rd, 2020. The effects of any dose of tetrahydrocannabinol (THC) or cannabidiol (CBD) on both general QoL and mental well-being were evaluated. The intervention had to be given for at least a week to establish a steady-state concentration. Effect size was calculated using Hedges g. Risk of bias of included studies was assessed using Cochrane’s Risk of Bias tool 2.0.

RESULTS

We retrieved no publications on cannabinoids use and QoL in glioma and, therefore, we expanded the search to cannabinoid use in other cancer types and chronic central nervous system (CNS) diseases. Sixteen studies were identified: four in cancer and twelve in CNS disease. Meta-analysis showed no effect of cannabinoids on general QoL (twelve studies in 1,740 patients; g = -0.02, 95% CI -0.11 to 0.07, p = 0.65) and mental well-being (twelve studies in 1,587 patients; g = -0.00, 95% CI -0.15 to 0.14, p = 0.96). Risk of bias was low in five studies, raised some concern in one study and was high in ten studies, mainly due to possible unblinding of patients after psychoactive adverse effects.

CONCLUSION

No studies on the effects of cannabinoids on QoL in glioma patients have been reported. A pooled analysis of studies in oncological patients and patients with CNS disease showed no effect of cannabinoids on QoL or mental well-being. However, studies were clinically heterogeneous and only one small study investigated monotherapy CBD with undecided results. As many glioma patients currently use cannabinoids, and monotherapy CBD has not been sufficiently investigated, future studies are necessary to evaluate its value in this specific population.

SUPPORT/DISCLOSURE

This meta-analysis has been funded by The Anita Veldman Foundation (CCA-2019-2-21).

Prognostic significance of genome-wide DNA methylation profiles within the randomised, phase 3, EORTC CATNON trial on non-1p/19q deleted anaplastic glioma

Background

Survival in patients with IDH1/2-mutant (mt) anaplastic astrocytomas is highly variable. We have used the prospective phase 3 CATNON trial to identify molecular factors related to outcome in IDH1/2mt anaplastic astrocytoma patients.

Methods

The CATNON trial randomized 751 adult patients with newly diagnosed 1p/19q non-codeleted anaplastic glioma to 59.4 Gy radiotherapy +/− concurrent and/or adjuvant temozolomide. The presence of necrosis and/or microvascular proliferation was scored at central pathology review. Infinium MethylationEPIC BeadChip arrays were used for genome-wide DNA methylation analysis and the determination of copy number variations (CNV). Two DNA methylation-based tumor classifiers were used for risk stratification. Next-generation sequencing (NGS) was performed using 1 of the 2 glioma-tailored NGS panels. The primary endpoint was overall survival measured from the date of randomization.

Results

Full analysis (genome-wide DNA methylation and NGS) was successfully performed on 654 tumors. Of these, 432 tumors were IDH1/2mt anaplastic astrocytomas. Both epigenetic classifiers identified poor prognosis patients that partially overlapped. A predictive prognostic Cox proportional hazard model identified that independent prognostic factors for IDH1/2mt anaplastic astrocytoma patients included; age, mini-mental state examination score, treatment with concurrent and/or adjuvant temozolomide, the epigenetic classifiers, PDGFRA amplification, CDKN2A/B homozygous deletion, PI3K mutations, and total CNV load. Independent recursive partitioning analysis highlights the importance of these factors for patient prognostication.

Conclusion

Both clinical and molecular factors identify IDH1/2mt anaplastic astrocytoma patients with worse outcome. These results will further refine the current WHO criteria for glioma classification.

Bevacizumab and dose-intense temozolomide in recurrent high-grade glioma

BACKGROUND

Angiogenesis inhibition is a rational treatment strategy for high-grade glioma (HGG). Combined antiangiogenic therapy and chemotherapy could be beneficial, taking advantage of different mechanisms of antitumour activity of both therapies. We carried out a phase I-II clinical trial with the combination of bevacizumab and continuous dose-intense temozolomide (TMZ) for patients with a recurrent HGG after first- or second-line treatment.

PATIENTS AND METHODS

Twenty-three HGG patients were treated with bevacizumab (10 mg/kg i.v. every 3 weeks) and TMZ (daily 50 mg/m(2)), until clinical or radiological progression. Conventional and dynamic magnetic resonance imaging (MRI) were carried out on days -4, 3 and 21 and until clinical or radiological progression.

RESULTS

Overall response rate (20%), 6-month progression-free survival (PFS6) (17.4%), median progression-free survival (13.9 weeks) and median overall survival (OS) (17.1 weeks) were considerably lower compared with most other studies with bevacizumab-containing regimens. The dynamic MRI parameters contrast transfer coefficient and relative cerebral blood volume decreased rapidly during the early phases of treatment, reflecting changes in vascularisation and vessel permeability but not in tumour activity. In addition, >50% of patients showed oedema reduction and a reduced shift on T1 images.

CONCLUSION

Treatment with bevacizumab and TMZ is feasible and well tolerated but did not improve PFS6 and median OS.

[Acute renal insufficiency caused by bilateral ureteral obstruction after appendectomy in a 6-year old boy]

A 6-year-old boy developed macroscopic haematuria on the 4th day after appendectomy for acute appendicitis, at which the appendix was found to be perforated. During the next few days the urine secretion decreased and malaise, pain in the lower abdomen, nausea and vomiting occurred. On a management of ample fluid administration, the urine secretion recovered and the symptoms subsided in a few days. In the early postoperative stage after appendectomy in children the possibility should be kept in mind of the development of acute renal insufficiency due to bilateral ureteral obstruction as a result of oedema of the posterior bladder wall, even if by means of ultrasonography only mild to moderate abnormalities are noted. Awaiting decompression by means of the introduction of bilateral ureteric stents, in order to prevent irreversible renal damage, supportive therapy with fluid administration depending on the diuresis seems indicated.