PL02.5.A The clinical significance of telomerase reverse transcriptase (TERT) promoter mutations, telomere length and O6-methylguanine DNA methyltransferase (MGMT) promoter methylation status in newly diagnosed and recurrent IDHwildtype glioblastoma (GBM) patients (PTS): A large mono-institutional study

BACKGROUND

the clinical significance of TERT promoter mutations, telomere length and their interactions with MGMT promoter methylation status in patients with IDH-wildtype GBM patients remain unclear. We performed a large monoinstitutional study to better investigate their impact and their interaction on clinical outcomes

MATERIAL AND METHODS

TERT promoter mutations (C228T and C250T), relative telomere length (RTL) and MGMT methylation status were assessed in 278 newly diagnosed and in 65 recurrent IDH-wildtype GBM PTS which were treated at Veneto Institute of Oncology (Padua, Italy) from Dec 2016 to Jan 2020. We have retrospectively explored association between gene characteristics and neuroradiological response (RANO criteria), progression-free survival (PFS), overall survival (OS). Telomere length was measured by monochrome multiplex PCR and RTL values were calculated as a telomere/single-copy gene ratio

RESULTS

characteristics of newly diagnosed GBM PTS were: median age 63 ys, ECOG PS 0–1 in 71% of PTS, radical surgery in 38%, 78% received radiation therapy plus TMZ, MGMT was methylated in 53%, TERT promoter was mutated in 80% (75% C228T, 25% C250T), median RTL was 1.57 (range 0.4–11.37). Objective response rate was reported in 15% of PTS, median OS was 15ms (95% CI 13-18ms), median PFS was 8ms (95% CI 7-9ms). At multivariable analysis, TERT promoter mutations and RTL were not associated with clinical outcomes; about OS, TERT promoter mutations and RTL reported a HR of 1.05 (95% CI 0.64–1.64) and 0.99 (95% CI 0.89–1.10), respectively; MGMT methylated tumors showed significant improved PFS and OS with a HR of 0.54 (95% CI 0.40–0.71) and 0.47 (95% CI 0.34–0.64), respectively. All interactions among MGMT status, TERT mutation status and RTL were not statistically significant. Characteristics of recurrent GBM PTS were: median age 55 ys, ECOG PS 0–1 in 60% of PTS, MGMTmet in 37%, TERT promoter mutations in 75% (75% C228T, 25% C250T), RTL was 1.67 (range 0.68–8.87). At multivariable analysis, only MGMT methylated tumors resulted significantly associated to prolonged OS (HR 0.16; 95% CI 0.07–0.40). No gene interaction was significant

CONCLUSION

for the first time worldwide, we analyzed the impact of TERT promoter mutations, RTL and MGMT methylation status in both newly diagnosed and recurrent IDH-wildtype GBM PTS. TERT promoter status and RTL were not associated with clinical outcomes at both diagnosis and relapse. MGMT promoter methylation status was the only prognostic factor in both cases. No significant interaction was demonstrated between TERT promoter mutations, RTL and MGMT methylation status

P04.07 The molecular evolution of oligodendrogliomas

BACKGROUND

Oligodendroglioma (OD) is defined by the presence of both IDH1/2 mutation and 1p/19q codeletion. Although prognosis of OD patients is relatively favorable, tumours usually relapse and often evolve to a higher malignancy grade, with some acquiring the treatment induced hypermutated phenotype. To better understand how these tumours evolve in time, we examined the molecular differences between matched primary and recurrent ODs.

MATERIAL AND METHODS

We identified 21 patients who underwent surgery at least twice [male: 11, female: 10, median age: 44 years (31–66)]. Clinical data were available for 14/21 patients: 5/14 received a treatment between resections [4 radiotherapy, 1 radiotherapy followed by PCV chemotherapy]; median time from the first to the second surgery was 71.5 months (12–158). Whole genome DNA-methylation analysis was performed using Illumina’s MethylationEPIC ‘850K’ BeadChip. Results were evaluated using the Molecularneuropathology.org platform (version 3.1.5) and in R.

RESULTS

Most samples were WHO grade 2 ODs [14, 10 and 1 tumours in first, second and third resection group, respectively]; WHO grade 3 was found in 6, 10 and 3 tumours in first, second and third resection, respectively; in 4 patients the tumour showed malignant progression from grade 2 to 3. Most ODs exhibited an IDH1 R132H mutation [17/21 patients]; in no cases was IDH1/2 mutation lost during progression. DNA methylation analysis was successfully performed in 41/45 cases [primary OD: 17, recurrent OD: 24] for a total of 18 matched pairs. 37 samples were assigned to the “IDH mutant glioma, subclass 1p/19q codeleted OD”; the remaining 4 were assigned to various other methylation classes but CNV (copy number variation) analysis confirmed the 1p19q codeletion in all samples. Recurrent tumours exhibited de novo loss of chromosome 4 in 3/24 cases (12.5%) and loss of chromosome 13 in 3/24 cases (12.5%). In unsupervised analysis of the 1000 most variable CpG sites, samples from the same patient clustered together. This indicates that the inter-tumour variability is greater than the intra-, temporal- or grading variability between tumours. There were no overt differences in DNA methylation levels between the primary and matched recurrent OD. However, lower genome wide DNA methylation levels were observed in tumours that dedifferentiated to grade 3 ODs compared to those of grade 2, indicating that DNA demethylation is associated to higher malignancy grade.

CONCLUSION

DNA methylation analysis in a cohort of primary and recurrent oligodendrogliomas highlights the genomic and epi-genetic changes that are acquired at tumour progression. We are currently expanding the cohort and collecting/integrating the clinical data to better explore the evolution of recurrent ODs.

P14.19 Regorafenib in recurrent glioblastoma patients: a large real-life experience

BACKGROUND

Regorafenib (REG), an oral multikinase inhibitor of angiogenic, stromal, and oncogenic receptor tyrosine kinases showed encouraging benefit in recurrent GBM patients enrolled in the randomized, phase 2 REGOMA trial. We investigated the clinical outcome and safety of REG in a real-life population of recurrent glioblastoma patients treated at Veneto Institute of Oncology as off-label use.

MATERIAL AND METHODS

Patients receiving REG at Veneto Institute of Oncology (Padua, Italy) were entered prospectively on a clinical database. Data were retrospectively analyzed. The primary endpoints of the study were overall survival (OS) and safety. The major inclusion criteria were: histologically confirmed diagnosis of GBM, disease progression as defined by RANO criteria after surgery followed by radiochemotherapy with temozolomide, ECOG PS ≤ 2; PTS with ≥ 2 prior lines of therapy were excluded. According to original schedule, patients received REG 160 mg once daily for the first 3 weeks of each 4-week cycle until disease progression, death, unacceptable toxicity, or consent withdrawal. Kaplan-Meier method was used to estimate the survival curves, RANO criteria for radiological assessment, CTCAE v5.0 for drug related adverse events.

RESULTS

From February 2018 to September 2020, 54 consecutive patients were treated with REG and enrolled in this study: median age was 56, ECOG PS 0–1 in 91% of patients, MGMTmet in 53%, second surgery at the time of relapse were performed in 30% of enrolled patient, 41% of patients underwent steroids at baseline. At the time of analysis, median follow-up was 11.1 ms, 30 PTS (56%) had died and 50 PTS (93%) had progressed. Median OS was 10.2 ms (95%CI, 6.4–13.9), 12m-OS was 43%; median PFS was 2.3ms (95%CI, 1.3–3.3) and 6m-PFS was 18%. All patients were evaluable for response: disease control rate (DCR) was 46.3%; stable disease was reported in 38.8% and partial response in 7.4%. Age, MGMT status and corticosteroid use at baseline were not statistically significant on multivariate analysis for OS. Grade 3 drug-related adverse events (AEs) occurred in 10 patients (18%) and the most frequent were hand-foot skin reaction, asthenia and increased lipase and transaminases; 1 PT (2%) reported a grade 4 AE (rash maculo-papular). AEs led to REG dose reductions in 37% of patients and, it was permanently discontinued in 5%. No death was considered to be drug-related.

CONCLUSION

We reported a large, mono-institutional “real world” experience of REG in recurrent glioblastoma patients. Overall, results are close to those reported in REGOMA trial although, we showed a longer OS. Toxicity was moderate and manageable. Encouraging clinical benefits of REG in recurrent GBM population were confirmed.

The generalized Wiener-Hopf equations for wave motion in angular regions: electromagnetic application

In this work, we introduce a general method to deduce spectral functional equations and, thus, the generalized Wiener-Hopf equations (GWHEs) for wave motion in angular regions filled by arbitrary linear homogeneous media and illuminated by sources localized at infinity with application to electromagnetics. The functional equations are obtained by solving vector differential equations of first order that model the problem. The application of the boundary conditions to the functional equations yields GWHEs for practical problems. This paper shows the general theory and the validity of GWHEs in the context of electromagnetic applications with respect to the current literature. Extension to scattering problems by wedges in arbitrarily linear media in different physics will be presented in future works.

Psychological status and role of caregivers in the neuro-rehabilitation of patients with severe Acquired Brain Injury (ABI)

OBJECTIVE

To investigate the relationships between (a) the psychological status of the caregiver, (b) the specific features of caregiving as perceived by the cognitive therapist in neuro-rehabilitation, (c) the caregivers' subjective approach to neuro-rehabilitation, and (d) the functional outcome of the patient.

METHODS

Twenty-four patients with severe acquired brain injury and their 24 caregivers participated in this observational study. Caregivers underwent a psychological assessment examining emotional distress, burden and family strain; their subjective approach to neuro-rehabilitation has been evaluated by two specific answers. The patients' cognitive therapists responded to an ad-hoc questionnaire, namely the "Caregiving Impact on Neuro-Rehabilitation Scale" (CINRS), evaluating the features (i.e., amount and quality) of caregiving. Finally, the functional outcome of the patient was assessed through standardized scales of disability and cognitive functioning.

RESULTS

The caregivers' psychological well-being was associated to the features of caregiving, to the subjective approach to neuro-rehabilitation, and to the functional recovery of their loved ones. A better caregivers' approach to neuro-rehabilitation was also associated to an overall positive impact of caregiving in neuro-rehabilitation and to a better functional outcome of the patients.

CONCLUSIONS

We posited a virtuous circle involving caregivers within the neuro-rehabilitation process, according to which the caregivers' psychological well-being could be strictly associated to a better level of caregiving and to a better functional outcome of the patients that, in turn, could positively influence the caregivers' psychological well-being. Although preliminary, these results suggest a specific psycho-educational intervention, aimed at improving the caregivers' psychological well-being and at facilitating their caring of the loved one.

Circulating fractures-related microRNAs distinguish primary hyperparathyroidism-related from estrogen withdrawal-related osteoporosis in postmenopausal osteoporotic women: A pilot study

Primary hyperparathyroidism (PHPT) represents a common cause of secondary osteoporosis in postmenopausal women, where the negative effect of estrogen withdrawal and that of hyperparathyroidism on bone mineralization coexist. Circulating microRNAs (miRNAs) expression profile has been correlated to both osteoporosis and fragility fractures. The study aimed to profile a set of miRNAs associated with osteoporotic fractures, namely miR-21-5p, miR-23a-5p, miR-24-2-5p, miR-24-3p, miR-93-5p, miR-100-5p, miR-122-5p, miR-124-3p, miR-125b-5p and miR-148-3p, in the plasma of 20 postmenopausal PHPT women. PHPT miRNAs profiles were compared with those detected in 10 age-matched postmenopausal non-PHPT osteoporotic women (OP). All the 10 miRNAs were detected in the plasma samples of both PHPT and OP women. The miRNA profiles clearly distinguished PHPT from OP samples, and identified within the PHPT group, two clusters differing for the PHPT severity, in term of ionized calcium and bone mineralization. In particular, miR-93-5p was significantly downregulated in PHPT samples, while miR-24-3p negatively correlated with the T-score at lumbar, femur neck and total hip sites. PHPT women who experienced osteoporotic fractures had plasma miR-24-3p levels higher than those detected in unfractured PHPT women. In conclusion, PHPT may modulate circulating fractures-related miRNAs, in particular, miR-93-5p, which may distinguish estrogen-related from PHPT-related osteoporosis.

PL2.2 Pembrolizumab (PEM) in recurrent high-grade glioma (HGG)patients with mismatch repair deficiency (dMMR): an observational study

BACKGROUND

Pem, an immune checkpoint inhibitor, demonstrated to be activein various neoplasms with MMRd. No data exists about its efficacy in MMRdglioma patients.

MATERIAL AND METHODS

MMRd HGG relapsed after receiving RT and CT weretreated with Pem. MMR status was analyzed by immunohistochemistry,including the MLH1, MSH2, MSH6, and PMS2 markers. MMR deficiency wasdefined as presence of a weak (wMMRd) or absent (aMMRd) signal atimmunohistochemistry for at least one MMR protein. Other inclusion criteriawere: ECOG PS 0–2, histologically confirmed gliomas, dexamethasone ≤4 mg.Pem was administrated at 200 mg every 3 weeks until progression disease orunacceptable toxicity. Tumor response was evaluated by brain MRI every 10 weeksaccording to the RANO criteria. OS and PFS were evaluated by Kaplan-Meiercurves. CTCAE v4.0 was used for toxicity.

RESULTS

among 167 glioma patients, we found 22 MMRd gliomas. 12 PTS were treated with Pem: 8 wMMRd and 4 aMMRd. According to Bethesda criteria, allPTS had microsatellite stability. Tumor histologies included 5 anaplasticastrocytoma, 1 anaplastic oligodendroglioma, 6 glioblastoma (GBM). MSH2deficiency was found in 6 cases, MSH6 deficiency in 9 cases, PMS2 and MLH1deficiency in 2 cases. Median number of prior line of chemotherapy was 1 (range 1–5). Stable disease (SD) was reported in 4 PTS (33%); 8 PTS showedprogressive disease (PD). PTS with anaplastic gliomas showed a statisticallysignificant association with SD (p=0.03, OR=3); all GBM PTS reported PD; status of MMRd (weak/absent), IDH (mutated/wild-type), MSH2 and MLH6(deficient/proficient) were not associated with SD. Median follow up was 14.7 ms. OS was 5.6 ms (95% CI 0.1–13.8), PFS 2.4 ms (95% CI 1.8–2.9). OS was 2.8 ms and 5.6 ms (p=0.9), PFS was 1.8 ms and 3.1 ms (p=0.5) in PTS with wMMRd and aMMRd. PTS reporting SD and PD had PFS of 7.4 ms (95% CI 4.6–10.2) and 1.8 ms (95% CI 0.2–3.4), p=0.002; OS was “not reached” and 2.8 ms in PTS having SD vs PD (p=0.04). Grade ≥3 adverse eventswere reported in 8% of PTS.

CONCLUSION

a subgroup of recurrent MMRd HGG might benefit from Pem,especially anaplastic gliomas. There was a trend for a longer PFS and OS in PTS with aMMRd. Analyses for identifying additional molecular predictive factors is ongoing.

PL3.2 Trabectedin for recurrent WHO grade II or III meningioma: a randomized phase II study of the EORTC Brain Tumor Group (EORTC-1320-BTG)

BACKGROUND

EORTC-1320-BTG investigated the activity, safety and quality of life of therapy with the tetrahydroisoquinoline alkaloid trabectedin (Yondelis®) in patients with recurrent higher-grade meningiomas. Trabectedin was originally derived from the Caribbean sea squirt, Ecteinascidia turbinata, and currently is manufactured by total synthesis.

METHODS

Adult patients with histological diagnosis of WHO grade II or III meningioma and radiologically documented progression after maximal feasible surgery and radiotherapy were randomly assigned in a 2:1 ratio to receive intravenous trabectedin (1.5 mg/m2every three weeks) or local standard of care (LOC). The primary endpoint was progression-free survival (PFS).

RESULTS

Within 22.1 months, we randomized a total of 90 patients (n=29 in LOC arm, n=61 in trabectedin arm) in 35 institutions and nine countries. In the LOC arm, the following treatments were administered: hydroxyurea (n=11), bevacizumab (n=9), none (n=4), chemotherapy (n=3), somatostatin analogue (n=1), combined chemotherapy and somatostatin analogue (n=1). With 71 PFS events, median PFS was 4.17 months in the LOC and 2.43 months in the trabectedin arm (hazard ratio [HR] for progression, 1.42; 80% CI, 1.00–2.03; p=0.204) with a PFS-6 rate of 29.1% (95% CI, 11.9%-48.8%) in the LOC and 21.1% (95% CI, 11.3%-32.9%) in the trabectedin arm. Median OS was 10.61 months in the LOC and 11.37 months in the trabectedin arm (HR for death, 0.98; 95% CI, 0.54–1.76; p=0.94).Grade 3 to 5 adverse events occurred in 44.4% (18.5% related, 4 serious adverse events, 0 lethal events) of the patients in the LOC and 59% (32.8% related, 57 serious adverse events and 2 toxic deaths) of patient in the trabectedin arm.

CONCLUSIONS

In this first prospective randomized trial performed in recurrent grade II or III meningioma, trabectedin did not improve PFS and OS and was associated with significantly higher toxicity as compared to LOC treatment. The data collected in this study may serve as benchmark for future clinical trials in this setting.

OS7.3 Health-related quality of life (HRQoL) evaluation in the REGOMA trial: a randomized, phase II clinical trial analyzing regorafenib activity in relapsed glioblastoma patients

BACKGROUND

REGOMA trial showed that regorafenib (REG) significantly improved OS and PFS in patients (pts) with relapsed GBM with respect to lomustine (LOM). REG showed a different toxicity profile compared to LOM. Here, we report final results of the HRQoL assessment, a secondary end point.

MATERIAL AND METHODS

HRQoL was measured using the European Organization for Research and Treatment of Cancer (EORTC) core questionnaire (QLQ-C30) and brain module (QLQ-BN20) administered before any MRI assessments, every 8 weeks (+/- 2 weeks) until disease progression. To evaluate treatment impact on HRQoL, questionnaires at progression were excluded. Mixed-effect linear models were fitted for each of the HRQOL domain to examine the change over progression-free time within and between arms. The models included the time of questionnaire assessment, the treatment group and their interaction, as fixed effects, and a compound symmetry covariance structure for the random effects. Differences of at least 10 points were classified as a clinically meaningful change. To correct for multiple comparisons and to avoid type I error, the level of significance was set at P=0.01 (2-sided).

RESULTS

Of 119 randomized pts, 117 partecipated in the HRQoL evaluation, and 114 had a baseline assessment (n=56 REG; n=58 LOM). No statistically significant differences were observed in any generic or cancer specific domain during treatment in the REG and LOM arms, or between the two arms, except for the appetite loss scale which was significantly worse in PTS treated with REG (Global mean 14.7 (SD=28.6) vs 7.6 (SD=16.0); p=0.0081). The rate of pts with a clinically meaningful worsening for appetite loss was not statistically different between the two arms (9 out of 24 and 0 out of 13 in the REG and LOM arm, respectively;p=0.02).

CONCLUSION

In the REGOMA trial, HRQoL did not change during regorafenib treatment. Pts treated with regorafenib and lomustine reported no significant difference in HRQoL.

P14.83 Adjuvant chemotherapy after severe myelotoxicity during temozolomide chemoradiation in gliomas. It is feasibile? The talian Multicentric Study (AINO)

BACKGROUND

Malignant gliomas are aggressive primitive brain tumor in adults. Today, the standard of care is Temozolomide (TMZ) administered daily with radiation therapy, followed by adjuvant TMZ. TMZ treatment has been considered to have a low toxicity profile. However, during concomitant treatment some patient may develop a severe myelosuppression. This toxicity may be in some cases prolonged and lead to treatment discontinuation.

MATERIAL AND METHODS

We have retrospectively collected data from 5 italian neuro-oncological centers, about glioma patients who developed severe and prolonged hematological toxicity during concomitant chemoradiotherapy with TMZ. The purpouse of this study is to evaluate: percentage of patients receiving adjuvant chemotherapy after severe myelotoxicity; rate of toxicity observed during adjuvant chemotherapy.

RESULTS

54 glioma patients who developed myelosuppression of grade 3 or 4 were considered. Hystology was Glioblastoma in 45 patients (83%); 63% of patients were female. Myelotoxicity during concomitant phase occurred at a median of 4 weeks (range 1–8) from the start of treatment.After recovery of myelotoxicity 19 patients did not received any treatment while 35 (65%) were treated with chemotherapy (28 received standard TMZ, one TMZ with metronomic schedule, 2 lomustine and 4 other agents). Among patients treated with TMZ, 13 patients presented hematological toxicity grade 3–4 which required treatment discontinuation in 7 cases (20%).

CONCLUSION

we observed that 80 % of glioma patients presenting severe myelotoxicity during concomitant radiochemotherapy may be treated with maintenance TMZ after blood value recovery.

Perioperative multidisciplinary management of endoscopic transsphenoidal surgery for sellar lesions: practical suggestions from the Padova model

Perioperative management of patients with sellar lesion submitted to endoscopic transsphenoidal neurosurgery (TSS) lacks standardization and therefore it is committed to each center clinical practice. Although neurosurgical procedure remains the same for all sellar lesions, perioperative approach can require different measures depending on the underlying disease. With the aim of standardizing our perioperative procedures and sharing our experience with other centers involved in the management of pituitary disease, we developed a clinical care path for patients with sellar lesions candidate to endoscopic TSS. For the drafting of the following protocol, the national and international guidelines published in the last 5 years have been evaluated and integrated with our center experience accumulated in decades of clinical practice. A steering committee including medical doctors involved in management of patients with pituitary masses at the Padua Hospital reviewed current knowledge on this topic. The committee developed a first draft which was shared with a broader group of medical doctors to reach a preliminary consensus; when it was reached, the clinical care assistance pathway was confirmed, validated, and published in the local web-based health service. We want to present and share our experience with colleagues involved in the perioperative management of pituitary diseases in other centers.