A multi-institutional phase I study of acetazolamide with temozolomide in adults with newly diagnosed MGMT-methylated malignant glioma

Background

A significant unmet need exists for the treatment of glioblastoma, IDH-wildtype (GBM). Preclinical work shows that acetazolamide sensitizes GBM to temozolomide (TMZ) by overcoming TMZ resistance due to BCL-3-dependent upregulation of carbonic anhydrase. Acetazolamide is Food and Drug Administration-approved for the treatment of altitude sickness. Drug repurposing enables the application of drugs to diseases beyond initial indications. This multi-institutional, open-label, phase I trial examined a combination of acetazolamide and TMZ in patients with MGMT promoter-methylated high-grade glioma.

Methods

A total of 24 patients (GBM, IDH-wildtype = 22; Grade 4 astrocytoma, IDH-mutant = 1; Grade 3 astrocytoma, IDH-mutant = 1) were accrued over 17 months. All patients received oral acetazolamide (250 mg BID for 7 days increased to 500 mg BID for Days 8-21 of each 28-day cycle) during the adjuvant phase of TMZ for up to 6 cycles.

Results

No patient had a dose-limiting toxicity. Adverse events were consistent with known sequelae of acetazolamide and TMZ. In the 23 WHO Grade 4 patients, the median overall survival (OS) was 30.1 months and the median progression-free survival was 16.0 months. The 2-year OS was 60.9%. In total 37% of the study population had high BCL-3 staining and trended toward shorter OS (17.2 months vs N.R., P = .06).

Conclusions

The addition of acetazolamide is safe and tolerable in GBM patients receiving standard TMZ. Survival results compare favorably to historical data from randomized trials in patients with MGMT promoter-methylated GBM and support examination of acetazolamide in a randomized trial. BCL-3 expression is a potential biomarker for prognosis in GBM or for patients more likely to benefit from TMZ.

Systemic Treatment for Brain Metastasis and Leptomeningeal Disease in Breast Cancer Patients

PURPOSE OF REVIEW

Breast cancer with brain metastasis (BCBM) and leptomeningeal disease (LMD) are important clinical problems. Traditionally, patients with metastases to the brain and meninges were excluded from clinical trials; hence, robust, evidence-based treatment recommendations are lacking. In this review, we outline the systemic treatment options and ongoing clinical trials.

RECENT FINDINGS

Several recent studies have added to the systemic treatment options available. Antibody-drug conjugates have changed the therapeutic landscape. Combination treatment modalities that target multiple mechanisms including disruption of the blood brain barrier are increasingly being studied. Breast cancer with brain metastases and LMD is a heterogenous disease. While the prognosis remains grim, with more systemic treatment options, patients with BCBM are now living longer. Many ongoing clinical trials hold promise to further improve outcomes.

Phase I dose-escalation study of procaspase-activating compound-1 in combination with temozolomide in patients with recurrent high-grade astrocytomas

BACKGROUND

Procaspase-3 (PC-3) is overexpressed in various tumor types, including gliomas. Targeted PC-3 activation combined with chemotherapy is a novel strategy for treating patients with high-grade gliomas, with promising preclinical activity. This study aimed to define safety and tolerability of procaspase-activating compound-1 (PAC-1) in combination with temozolomide (TMZ) for patients with recurrent high-grade astrocytomas.

METHODS

A modified-Fibonacci dose-escalation 3 + 3 design was used. PAC-1 was administered at increasing dose levels (DL; DL1 = 375 mg) on days 1-21, in combination with TMZ 150 mg/m2/5 days, per 28-day cycle. Dose-limiting toxicity was assessed during the first 2 cycles. Neurocognitive function (NCF) testing was conducted throughout the study.

RESULTS

Eighteen patients were enrolled (13 GBM, IDH-wild type; 2 astrocytoma, IDH-mutant, grade 3; 3 astrocytoma, IDH-mutant, grade 4). Dose escalation was discontinued after DL3 (ie, PAC-1, 625 mg) due to lack of additional funding. Grade 3 toxicity was observed in 1 patient at DL1 (elevated liver transaminases) and 1 at DL 2 (headache). Two partial responses were observed at DL1 in patients with GBM, O6-methylguanine-DNA methyltransferase (MGMT) promoter methylated. Two patients had stable disease, and 11 experienced progression. NCF testing did not show a clear relationship between PAC-1 dose, treatment duration, and declines in NCF.

CONCLUSIONS

Combination of PAC-1 and TMZ was well tolerated up to 625 mg orally daily and TMZ orally 150 mg/m2/5 days per 28-day cycle. The maximum tolerated dose was not reached. Further dose escalation of PAC-1 in combination with TMZ is advised before conducting a formal prospective efficacy study in this patient population.

SCSS-02. INVOLVEMENT OF SUPPORTIVE CARE TEAM AND SOCIAL WORK IN NEUROONCOLOGY IN A TERTIARY CARE HOSPITAL

BACKGROUND/OBJECTIVES

Supportive Care and Social Work services are underutilized in Neurooncology. ASCO Quality Oncology Program Initiative (QOPI) includes emotional assessment by second and advance care planning (ACP) by third oncologic visit in solid malignancies. We looked (1) reason, location, and the duration from diagnosis for the involvement of supportive care teams and (2) what are the determining factors for advanced care planning in glioblastoma.

METHODS

After obtaining an IRB approval for the study, we performed a retrospective chart review of glioblastoma patients seen at University of Illinois Chicago 2015-2020 using the ICD Code C71.9 for malignant gliomas. Patients who had a pathologic diagnosis of glioblastoma, age > 18 years, and had their entire neurooncologic care at UIC were included in the study. Demographic features, socioeconomic determinants, tumor characteristics, and treatment history were noted. Supportive Care Teams and Social Work notes were reviewed.

RESULTS

Out of the total 403 patients, there were 78 glioblastoma patients. A total 33 met the inclusion criteria. 10 out of 33 had been seen by the supportive care team. Patients in both groups were equally matched for demographics, socioeconomic determinants, and tumor characteristics. ACP were significantly better documented in the supportive care group (p = 0.035). Supportive Care teams were consulted much later after the disease diagnosis, usually in the inpatient setting mostly consulted for goals of care discussion and hospice enrollment. There was a significant positive correlation between the involvement of Supportive Care team and Social Work.

DISCUSSION

A multidisciplinary clinic including an inbuilt palliative and social work teams can improve the Quality of Life (QoL) in glioblastoma patients and their caregivers. ICD code 99497 for a dedicated ACP discussion by the neurooncologist can be used. An ongoing phase III RCT EPCOG aims to assess (QoL) in patients with glioblastoma receiving early palliative intervention.

Case series of diffuse extraneural metastasis in H3F3A mutant high-grade gliomas: Clinical, molecular phenotype and literature review

H3K27M and H3.3G34R/V mutations have been identified in pediatric high-grade gliomas (pHGG), though extraneural metastases are rarely reported and poorly characterized. Three pHGG patients from two institutions were identified with extraneural metastasis, harboring histone mutations. Their clinical, imaging and molecular characteristics are reported here. A 17-year old female presented with supratentorial H3.3G34R-mutant glioma with metastatic osseous lesions in the spine, pelvis, bone marrow, pleural effusion and soft tissue of pelvis. Bone marrow biopsy and soft tissue of pelvis biopsy showed neoplastic cells positive for P53. A 20-year old female was diagnosed with H3F3A H3K27M-mutant thalamic glioma. She developed diffuse sclerotic osseous lesions. Biopsy of an osseous lesion was non-diagnostic. A 17-year old female presented with a H3F3A H3K27M-mutant diffuse midline glioma with diffuse spinal cord metastasis. She further developed multifocal chest lymphadenopathy, pleural effusions, and a soft tissue mass in the abdominal wall. The latter was positive for H3K27M mutation. We present the first case series of pHGG with H3F3A mutation and diffuse extraneural dissemination, describing their clinical and molecular profile.

ACTR-63. PHASE I DOSE ESCALATION STUDY OF PROCASPASE ACTIVATING COMPOUND-1 (PAC-1) IN COMBINATION WITH TEMOZOLOMIDE IN PATIENTS WITH RECURRENT ANAPLASTIC ASTROCYTOMA OR GLIOBLASTOMA

BACKGROUND

Procaspase activating compound -1 (PAC-1) is a small molecule that catalyzes conversion of procaspase-3 to caspase-3 which induces apoptosis in cancer cells. Glioblastoma (GBM) is among the tumors with high concentrations of procaspase-3 and low levels of caspase-3. PAC-1 crosses the blood brain barrier and has been shown to synergize with temozolomide (TMZ) in canine malignant glioma and meningioma that arise spontaneously.

METHODS

This is a multicenter phase 1 dose-escalation study to assess the maximum tolerated dose (MTD) of PAC-1 administered days 1–21 in combination with TMZ days 8–12 at a dose of 150 mg/m2 of each 28 day cycle in subjects with recurrent anaplastic astrocytoma (AA) or GBM. A modified Fibonacci 3 + 3 design is used with up to 4 dose levels of PAC-1 (375, 500, 625 and 750 mg/day). Neurologic toxicity, including cognitive function, is closely monitored throughout the trial. INTERIM DATA: A total of 14 subjects have been enrolled to-date. Of these, 7 at dose level 1, PAC-1 375 mg/day (6 GBM, 1 AA; median age 58y, range 25–75) and 7 at dose level 2, PAC-1 500 mg/day (5 GBM, 2 AA; median age 51y, range 35–60). Best responses to-date were 2 subjects with a partial response and 2 with stable disease. Grade 3 (hepatotoxicity) and 4 (cerebral edema) was reported as possibly related to PAC-1 in 1 patient at dose level 1. The median number of cycles received was 4 (range, 1–12+) at dose level 1 and 2 (range, 1–3) at dose level 2. Enrollment to dose level 2 has been completed and data analysis is ongoing. Updated response and toxicity as well as pharmacokinetic data will be presented.

RARE-28. HYPOTHALAMIC GERMINOMA AND NEUROSARCOIDOSIS: A TALE OF TWO PATHOLOGIES

CASE 1: 30-year-old Caucasian male with a history of hereditary cavernomas, testicular germ cell tumor s/p orchiectomy 2017 presented next year with a chief complain of increasing lethargy. MRI Brain showed a new expansile, homogenously enhancing hypothalamic lesion causing obstructive dilatation of the lateral ventricles. MRI of neuraxis was not concerning for leptomeningeal spread. Initial differentials included suprasellar germinoma vs chiasmatic hypothalamic glioma vs metastatic lesion. Biopsies X2 showed gliosis and granulomatous inflammation. Despite radiation treatment for the hypothalamic mass clinical course continued to deteriorate. CSF results showed RBC - 1,200; WBC - 51 with 77% lymphocytes, 3% neutrophils, 20% monocytes. FDG-PET did not reveal evidence of metastatic disease. He was treated presumptively for neurosarcoidosis with high-dose corticosteroids and azathioprine and later transitioned to methotrexate and infliximab. Follow up MRI scans showed a reduction in the hypothalamic mass. CASE 2: A 23-year-old African American male treated for ADEM in 2010 presented to clinic with behavioral problems in 2017. Initial presentation included lethargy with imaging showing an incidental hypothalamic mass. Initial differentials included germinoma vs infundibular hypophysitis vs granulomatous process. He was treated with immunotherapy (corticosteroids and IVIG) with partial resolution of the growth. He was later diagnosed with suprasellar germinoma on biopsy subsequently treated with 2 cycles chemotherapy and proton beam radiotherapy in 2012. In 2017. to exclude tumor recurrence an LP showed elevated ACE however remainder of the clinical picture was not suggestive of neurosarcoidosis. DISCUSSION: Multiple case series have been described wherein hypothalamic germinoma mimics isolated neurosarcoidosis and vice-versa. Because of similar clinical picture and radiographic findings, the diagnosis is challenging. ACE is a nonspecific test for neurosarcoidosis, and it can be positive in the setting of germinoma as well. Hence specific molecular markers may be helpful in the diagnosis.

Phase 1 lead-in to a phase 2 factorial study of temozolomide plus memantine, mefloquine, and metformin as postradiation adjuvant therapy for newly diagnosed glioblastoma

BACKGROUND

Repurposed memantine, mefloquine, and metformin have putative anticancer activity. The objective of this phase 1 study was to determine the maximum tolerated doses (MTDs) of combinations of these agents with temozolomide (TMZ).

METHODS

Adults with newly diagnosed glioblastoma who completed chemoradiation were eligible. The patients were assigned to receive doublet, triplet, or quadruplet therapy with TMZ combined with mefloquine, memantine, and/or metformin. Dose-limiting toxicities (DLTs) were determined, using a 3 + 3 study design.

RESULTS

Of 85 enrolled patients, 4 did not complete cycle 1 (the DLT observation period) for nontoxicity reasons, and 81 were evaluable for DLT. The MTDs for doublet therapy were memantine 20 mg twice daily, mefloquine 250 mg 3 times weekly, and metformin 850 mg twice daily. For triplet therapy, the MTDs were memantine 10 mg twice daily, mefloquine 250 mg 3 times weekly, and metformin 850 mg twice daily. For quadruplet therapy, the MTDs were memantine 10 mg twice daily, mefloquine 250 mg 3 times weekly, and metformin 500 mg twice daily. DLTs included dizziness (memantine) and gastrointestinal effects (metformin). Lymphopenia was the most common adverse event (66%). From study entry, the median survival was 21 months, and the 2-year survival rate was 43%.

CONCLUSIONS

Memantine, mefloquine, and metformin can be combined safely with TMZ in patients with newly diagnosed glioblastoma.

BRAF alterations in primary brain tumors

Primary brain tumors can harbor v-raf murine sarcoma viral oncogene homolog B1 (BRAF) gene alterations. BRAF is a serine/threonine kinase protein and is a downstream effector of the Ras-Raf-MEK extracellular signal-regulated kinase (ERK) signaling pathway, which is responsible for cell division and differentiation. BRAF-V600E mutations are most commonly found in pleomorphic xanthoastrocytoma, ganglioglioma, epithelioid glioblastoma, and gliomas diagnosed at a younger age; BRAF-KIAA1549 fusion is the most common BRAF alteration in pilocytic astrocytoma. First-generation BRAF inhibitors (BRAFi) have shown effectiveness in the treatment of melanoma patients with brain metastases and are currently undergoing clinical trials for the treatment of pediatric primary brain tumors with the BRAF-V600E mutation. Numerous case reports in adult primary brain tumors with BRAF-V600E mutations demonstrate signals of BRAFi activity in the brain. BRAFi are commonly combined with other inhibitors of the Ras-Raf-MEK-ERK pathway for the avoidance of BRAFi resistance, while second-generation BRAFi have been developed with safer side-effect profiles and decreased resistance. Primary brain tumors with KIAA1549-BRAF fusion should not be treated with first-generation BRAFi due to paradoxical activation of the Ras-Raf-MEK-ERK pathway.

Comparative efficacy of parathyroidectomy and active surveillance in patients with mild primary hyperparathyroidism: a systematic review and meta-analysis

Counseling for patients with primary hyperparathyroidism (PHPT) and mild hypercalcemia without indications for surgical intervention requires accurate estimates of the potential benefits of parathyroidectomy. We aim to summarize the available evidence regarding the benefits of parathyroidectomy that patients with mild PHPT without indications for surgery experience compared to observation. We searched multiple databases from inception to August 2015. We included randomized controlled trials (RCT) and observational studies that evaluated changes in bone health, quality of life or neuropsychiatric symptoms, or in the risk of nephrolithiasis, cardiovascular events, or death between patients undergoing parathyroidectomy or active surveillance. Eight studies were eligible. Risk differences were not significant, in part due to lack of events (fractures, nephrolithiasis, cardiovascular events, or deaths). No significant differences were observed across measures of bone health, quality of life, and neuropsychiatric symptoms. A single RCT evaluating bone mineral density (BMD) changes at 5 years found a small statistically significant effect favoring parathyroidectomy. Patients with mild PHPT without indications for surgery experience a limited number of adverse consequences during short-term follow-up limiting our ability to estimate the benefit of surgery during this timeframe. This information is helpful as these patients consider surgery versus active surveillance. Long-term data is warranted to determine who benefits in the long run from surgical intervention and the extent to which this benefit affects outcomes that matter to patients.

Degree of corticospinal tract damage correlates with motor function after stroke

OBJECTIVES

Direct injury to the corticospinal tract (CST) is a major factor defining motor impairment after stroke. Diffusion tensor imaging (DTI) tractography allows definition of the CST. We sought to determine whether DTI-based assessment of the degree of CST damage correlates with motor impairment at each phase of ischemic stroke.

METHODS

We evaluated patients at the acute (3-7 days), subacute (30 days), and chronic (90 days) phases of ischemic stroke with DTI and clinical motor scores (upper extremity Fugl-Myer test [UE-FM], motor items of the National Institutes of Health Stroke Scale [mNIHSS]). The CST was identified and virtual fiber numbers (FN) were calculated for the affected and contralateral CST. We used Spearman correlation to study the relationship of FN ratio (FNr) (affected/unaffected CST) with motor scores at each time point, and the regression model to study the association of the acute parameters with chronic motor scores.

RESULTS

We studied 23 patients. Mean age was 66.7 (±12) years. FNr correlated with UE-FM score in the acute (r = 0.50, P = 0.032), subacute (r = 0.57, P = 0.007), and chronic (r = 0.67, P = 0.0008) phase, and with mNIHSS in the acute (r = -0.48, P = 0.043), subacute (r = -0.58, P = 0.006), and chronic (r = -0.75, P = 0.0001) phase. The combination of acute NIHSS and FNr significantly predicted chronic UE-FM score (r = 0.74, P = 0.0001).

INTERPRETATION

DTI-defined degree of CST injury correlates with motor impairment at each phase of ischemic stroke. The combination of baseline FNr and NIHSS predicts motor outcome. DTI-derived CST assessment could become a surrogate marker of motor impairment in the design of neurorestorative clinical trials.

Eighteen months' experience with remote diagnosis, management and education in congenital heart disease

In July 1998, a telemedicine link was established between the Venizelio General Hospital in Crete and the Paediatric Cardiology Department of the Aghia Sophia Children's Hospital in Athens. The telemedicine link used ISDN at 384 kbit/s for diagnosis, management and education in congenital heart disease. Over 18 months, a total of 39 teleconsultations were carried out, concerning 93 children with haemodynamically significant cardiac abnormalities. Forty-four children (47%) were managed locally after teleconsultation, while three children with transposition of the great arteries (3%) were transported as emergency cases to Athens in the first days of life. The other 46 children (50%) had a scheduled appointment at a tertiary centre for cardiac catheterization, angiocardiography, operative treatment or surgical repair. The telemedicine link brought a number of benefits, such as better access to the tertiary centre and the avoidance of patient transportation.