NeuroOncology

Neuro-radiological characteristics of adult diffuse grade II and III insular gliomas classified according to WHO 2016 In the initial, online publication, the authors' given names were captured as family names and vice versa. The names are correctly shown here. The original article has been corrected.

Correction to: Monitoring of intracerebellarly-administered natural killer cells with fluorine-19 MRI There was a typo in author Andrew Wahba's name in the initial online publication. The original article has been corrected.

Comment on: Effects of surgery on neurocognitive function in patients with glioma: a meta-analysis of immediate post-operative and long-term follow-up neurocognitive outcomes

Incidence and clinicopathologic features of H3 K27M mutations in adults with radiographically-determined midline gliomas Abstract Purpose H3 K27 mutations, most commonly in H3F3A, are common in diffuse midline glioma. The exact frequency of these mutations in adults with gliomas in the midline location is unknown. This study was conducted to define the incidence of H3 K27M mutations in this location and to compare clinicopathological features with those of patients who do not harbor this mutation. Methods Consecutive glioma cases from 2007 to 2017 were screened for gliomas in the midline location. Immunohistochemistry was performed on all available tissue for mutations of H3 K27M, IDH1, and ARTX. Results Of 850 gliomas screened, 163 cases had midline glioma on MRI. Sufficient FFPE tissue was available for 123 cases (75%). H3 K27M mutation was identified in 18 of 123 cases (15%). All except one H3 K27M-mutant tumors were WHO grade III or IV on histology, while non-mutant tumors encompassed all four grades. The most common midline locations for H3 K27M-mutated tumors were midbrain (2/3; 67%), pons (4/11; 36%), and cerebellum (6/24; 25%). As compared to H3 K27M-wildtype tumors, there were no differences in age at diagnosis, sex, tumor grade, contrast enhancement on MRI, extent of resection, or treatment received. In this cohort, median survival was longer for patients with H3 K27M-mutated tumors (n = 18; 17.6 months) compared with high-grade wildtype tumors (n = 74; 7.7 months, p = 0.03). Conclusions H3 K27M mutations are common in midline gliomas in adults and can present in all midline locations. Survival comparison between H3 K27M-mutant and wildtype midline gliomas suggests that survival may be similar or possibly improved if the mutation is present.

Targeted radioimmunotherapy for embryonal tumor with multilayered rosettes Abstract Purpose We explored the use of intraventricular 131I-Omburtamab targeting B7-H3 in patients with ETMR. Methods Patients were enrolled in an IRB approved, phase 1, 3 + 3 dose escalation trial. Patients with CNS disease expressing the antibody target antigen B7-H3 were eligible. We report on a cohort of three patients with ETMR who were enrolled on the study. Three symptomatic children (ages 14 months, 3 and 3.5 years) had large parietal masses confirmed to be B7-H3-reactive ETMR. Patients received 2 mCi 131I-Omburtamab as a tracer followed by one or two therapeutic 131I-Omburtamab injections. Dosimetry was based on serial CSF, blood samplings and region of interest (ROI) on nuclear scans. Brain and spine MRIs and CSF cytology were done at baseline, 5 weeks after 131I-Omburtamab, and approximately every 3 months thereafter. Acute toxicities and survival were noted. Results Patients received surgery, focal radiation, and high dose chemotherapy. Patients 1 and 2 received 131I-Omburtamab (80 and 53 mCi, respectively). Patient 3 had a local recurrence prior to 131I-Omburtamab treated with surgery, external beam radiation, chemotherapy, then 131I-Omburtamab (36 mCi). 131I-Omburtamab was well-tolerated. Mean dose delivered by 131I-Omburtamab was 68.4 cGy/mCi to CSF and 1.95 cGy/mCi to blood. Mean ROI doses were 230.4 (ventricular) and 58.2 (spinal) cGy/mCi. Patients 1 and 2 remain in remission 6.8 years and 2.3 years after diagnosis, respectively; patient 3 died of progressive disease 7 months after therapy (2 years after diagnosis). Conclusions 131I-Omburtamab appears safe with favorable dosimetry therapeutic index. When used as consolidation following surgery and chemoradiation therapy, 131I-Omburtamab may have therapeutic benefit for patients with ETMR.

Impact of overall corticosteroid exposure during chemoradiotherapy on lymphopenia and survival of glioblastoma patients Abstract Purpose Corticosteroids are commonly used to alleviate symptoms from cerebral vasogenic edema in glioblastoma (GBM) patients. This study evaluated the impact of overall corticosteroid exposure during chemoradiotherapy (CRT) on acute severe lymphopenia (ASL) and survival outcomes of GBM patients. Methods GBM patients treated with CRT from 2007 to 2016 were retrospectively analyzed. Overall corticosteroid exposure was estimated as the average daily dexamethasone dose during 6 weeks of CRT. ASL was defined as grade 3 or higher lymphopenia within 3 months of starting CRT. ASL rates, overall survival (OS), and progression-free survival (PFS) were analyzed using Kaplan–Meier method. Multivariable analysis (MVA) was performed using logistic and Cox regression to identify independent predictors of ASL and survival outcomes, respectively. Results Of the 319 eligible patients, the median daily dexamethasone use was 2 mg/day. The high-dose dexamethasone cohort (> 2 mg/day) had significantly higher ASL and worse OS than the low-dose dexamethasone cohort: 3-month ASL of 43.7% versus 19.8% (p < 0.003) and median OS of 12.6 months versus 17.9 months (p < 0.001), respectively. On MVA, higher dexamethasone use was independently associated with higher ASL and worse OS, but not worse PFS. A subset analysis of patients with gross-total resection found that higher dexamethasone use was significantly associated with ASL, but not OS. Conclusion Increased corticosteroid use among GBM patients during CRT appears to be an independent risk factor for developing subsequent ASL. Its apparent association with worse OS may be influenced by other confounding factors and would need to be validated through prospective investigations.

Gamma Knife Stereotactic Radiosurgery favorably changes the clinical course of hemangioblastoma growth in von Hippel-Lindau and sporadic patients Abstract Purpose This is the first single-institution study of its size to characterize the treatment impact and to address the question of whether hemangioblastoma treatment with Gamma Knife Stereotactic Radiosurgery (GKRS) in both sporadic and VHL patients changes the characteristic saltatory hemangioblastoma growth pattern. Methods The authors reviewed a single-institution tumor registry to identify patients who had received GKRS for hemangioblastomas between January 1st, 1999, and December 31st, 2017. Results 15 patients with 101 lesions met search criteria with a median age of first GKRS of 39.2 years (interquartile range [IQR] of 25.7–57.4 years), including 96 VHL and 5 sporadic lesions. The median time from GKRS to last follow-up was 5.4 years (IQR 2.3–11.5 years). 4 lesions (4%) and 3 patients (20%) experienced a local failure. The 1-year, 3-year, and 5-year freedom from new hemangioblastoma formation rates were 97%, 80%, and 46% respectively. Multivariate analysis revealed a reduction in tumor volume after GKRS. Several variables associated with a greater percent reduction in volume from GKRS to last follow-up: non-cystic status (p = .01), no prior craniotomy (p = .04), and follow-up time from GKRS (p < .0001). Conclusions GKRS is a successful long-term treatment option for hemangioblastomas changing the clinical course from saltatory growth to reduction in tumor volume. Non-cystic tumors and those without prior craniotomy were associated with a greater percent reduction in volume from GKRS at last follow-up.

Impact on survival of early tumor growth between surgery and radiotherapy in patients with de novo glioblastoma Abstract Purpose Systematic pre-radiotherapy MRI in patients with newly resected glioblastoma (OMS 2016) sometimes reveals tumor growth in the period between surgery and radiotherapy. We evaluated the relation between early tumor growth and overall survival (OS) with the aim of finding predictors of regrowth. Methods Seventy-five patients from 25 to 84 years old (Median age 62 years) with preoperative, immediate postoperative, and preradiotherapy MRI were included. Volumetric measurements were made on each of the three MRI scans and clinical and molecular parameters were collected for each case. Results Fifty-four patients (72%) had an early regrowth with a median contrast enhancement volume of 3.61 cm3—range 0.12–71.93 cm3. The median OS was 24 months in patients with no early tumor growth and 17.1 months in those with early tumor regrowth (p = 0.0024). In the population with initial complete resection (27 patients), the median OS was 25.3 months (19 patients) in those with no early tumor growth between surgery and radiotherapy compared to 16.3 months (8 patients) in those with tumor regrowth. In multivariate analysis, the initial extent of resection (p < 0.001) and the delay between postoperative MRI and preradiotherapy MRI (p < 0.001) were significant independent prognostic factors of regrowth and of poorer outcome. Conclusions We demonstrated that, in addition to the well known issue of incomplete resection, longer delays between surgery and adjuvant treatment is an independent factors of tumor regrowth and a risk factor of poorer outcomes for the patients. To overcome the delay factor, we suggest shortening the usual time between surgery and radiotherapy.

Tumor control and survival in patients with ten or more brain metastases treated with stereotactic radiosurgery: a retrospective analysis Abstract Introduction To assess tumor control and survival in patients treated with stereotactic radiosurgery (SRS) for 10 or more metastatic brain tumors. Methods Patients were retrospectively identified. Clinical records were reviewed for follow-up data, and post-treatment MRI studies were used to assess tumor control. For tumor control studies, patients were separated based on synchronous or metachronous treatment, and control was assessed at 3-month intervals. The Kaplan–Meier method was employed to create survival curves, and regression analyses were employed to study the effects of several variables. Results Fifty-five patients were treated for an average of 17 total metastases. Forty patients received synchronous treatment, while 15 received metachronous treatment. Univariate analysis revealed an association between larger brain volumes irradiated with 12 Gy and decreased overall survival (p = 0.0406); however, significance was lost on multivariate analysis. Among patients who received synchronous treatment, the median percentage of tumors controlled was 100%, 91%, and 82% at 3, 6, and 9 months, respectively. Among patients who received metachronous treatment, the median percentage of tumors controlled after each SRS encounter was 100% at all three time points. Conclusions SRS can be used to treat patients with 10 or more total brain metastases with an expectation of tumor control and overall survival that is equivalent to that reported for patients with four or fewer tumors. Development of new metastases leading to repeat SRS is not associated with worsened tumor control or survival. Survival may be adversely affected in patients having a higher volume of normal brain irradiated.

A multicenter phase II study of temozolomide plus disulfiram and copper for recurrent temozolomide-resistant glioblastoma Abstract Purpose Preclinical studies have suggested promising activity for the combination of disulfiram and copper (DSF/Cu) against glioblastoma (GBM) including re-sensitization to temozolomide (TMZ). A previous phase I study demonstrated the safety of combining DSF/Cu with adjuvant TMZ for newly diagnosed GBM. This phase II study aimed to estimate the potential effectiveness of DSF/Cu to re-sensitize recurrent GBM to TMZ. Methods This open-label, single-arm phase II study treated recurrent TMZ-resistant GBM patients with standard monthly TMZ plus concurrent daily DSF 80 mg PO TID and Cu 1.5 mg PO TID. Eligible patients must have progressed after standard chemoradiotherapy and within 3 months of the last dose of TMZ. Known isocitrate dehydrogenase (IDH) mutant or secondary GBMs were excluded. The primary endpoint was objective response rate (ORR), and the secondary endpoints included progression-free survival (PFS), overall survival (OS), clinical benefit (response or stable disease for at least 6 months), and safety. Results From March 2017 to January 2018, 23 recurrent TMZ-resistant GBM patients were enrolled across seven centers, and 21 patients were evaluable for response. The median duration of DSF/Cu was 1.6 cycles (range: 0.1–12.0). The ORR was 0%, but 14% had clinical benefit. Median PFS was 1.7 months, and median OS was 7.1 months. Only one patient (4%) had dose-limiting toxicity (grade three elevated alanine transaminase). Conclusions Addition of DSF/Cu to TMZ for TMZ-resistant IDH-wild type GBM appears well tolerated but has limited activity for unselected population.