The Clinical Characteristics and Outcomes of Incidentally Discovered Glioblastoma

Objective With an increase in the number of imaging examinations and the development of imaging technology, a small number of glioblastomas (GBMs) are identified by incidental radiological images. These incidentally discovered glioblastomas (iGBMs) are rare, and their clinical features are not well understood. Here, we investigated the clinical characteristics and outcomes of iGBM. Methods Data of newly diagnosed iGBM patients who were treated at our institution between August 2005 and October 2019 were reviewed. An iGBM was defined as a GBM without a focal sign, discovered on radiological images obtained for reasons unrelated to the tumor. Kaplan-Meier analysis was performed to calculate progression-free survival (PFS) and overall survival (OS). Results Of 234 patients with newly diagnosed GBM, four (1.7%) were classified as having iGBM. Health screening was the most common reason for tumor discovery (75.0%). The preoperative Karnofsky performance status score was 100 in three patients. Tumors were found on the right side in three cases. The mean volume of preoperative enhanced tumor lesion was 16.8 cm3. The median duration from confirmation of an enhanced lesion to surgery was 13.5 days. In all cases, either total (100%) or subtotal (95–99%) resections were achieved. The median PFS and OS were 11.5 and 20.0 months, respectively. Conclusions The iGBMs were often small and in the right non-eloquent area, and the patients had good performance status. We found that timely therapeutic intervention provided iGBM patients with favorable outcomes. This report suggests that early detection of GBM may lead to a better prognosis.

Is Function-Based Resection Using Intraoperative Awake Brain Mapping Feasible and Safe for Solitary Brain Metastases Within Eloquent Areas?

ObjectiveTo assess feasibility and safety of function-based resection under awake conditions for solitary brain metastasis patients.MethodsRetrospective, observational, single-institution case-control study (2014-2019). Inclusion criteria: adult patients, solitary brain metastasis, supratentorial location within eloquent areas, function-based awake resection. Case matching (1:1) criteria between metastasis group and control group (high-grade gliomas): sex, tumor location, tumor volume, preoperative Karnofsky Performance Status score, age, educational level.ResultsTwenty patients were included. Intraoperatively, all patients were cooperative, no obstacles precluded procedure from being performed. A positive functional mapping was achieved at both cortical and subcortical levels, allowing for a function-based resection in all patients. The case-matched analysis showed that intraoperative and postoperative events were similar, except for a shorter duration of the surgery (p<0.001) and of the awake phase (p<0.001) in the metastasis group. A total resection was performed in 18 cases (90%, including 10 supramarginal resections), and a partial resection was performed in two cases (10%). At three months postoperative months, none of the patients had worsening of their neurological condition or uncontrolled seizures, three patients had an improvement in their seizure control, and seven patients had a Karnofsky Performance Status score increase ≥10 points.ConclusionsFunction-based resection under awake conditions preserving the brain connectivity is feasible and safe in the specific population of solitary brain metastasis patients and allows for high resection rates within eloquent brain areas while preserving the overall and neurological condition of the patients. Awake craniotomy should be considered to optimize outcomes in brain metastases in eloquent areas.

NCOG-76. BASELINE COGNITIVE ASSESSMENT IN GLIOMA PATIENTS WITH MGMT PROMOTOR METHYLATION AND/OR 1p19q CODELETION

INTRODUCTION Methylguanine methyltransferase (MGMT) methylation status is associated with better overall survival while 1p19q co-deletion is associated with long-term survival. Cognitive dysfunction is a common complication of brain tumors and treatment; however, information regarding the relationship between MGMT status, 1p19q codeletion, and cognition is limited. METHOD Baseline neuropsychological testing was performed in patients with malignant glioma prior to radiation and/or chemotherapy administration. A retrospective data analysis was conducted. We calculated composite and subdomain scores for attention/executive functioning, memory, and language in patients with or without MGMT promotor methylation and/or 1p19q codeletion. RESULTS Thirty-eight patients (Age M = 48.73 ± 14.98; 50% female) diagnosed with glioma (29% grade II, 16% grade III, 21% grade IV; Karnofsky Performance Status score (KPS) M = 88.75 ± 14.24) were selected from a retrospective. Memory was marginally significant, such that methylated participants performed better on memory tasks than the unmethylated group (p = .053). Independent samples t-test revealed no significant differences between either marker across the overall cognitive composite (methylated M = 41.35; unmethylated: M = 39.91; p = .955; 1p19q co-deleted: M = 50.94; 1p19q intact: M = 43.66; p = .158) and subdomains attention/executive functioning (p = .585; p = .157) and language (p = .581; p = .765). Logistic regression showed MGMT does not predict cognitive status (p =.052) and there were not enough cases to complete the model with 1p19q. CONCLUSION MGMT status may be correlated with baseline cognitive status as MGMT methylated patients had better memory scores than their unmethylated counterparts. We did not find any significant association between the remaining cognitive domains and MGMT or 1p19q although sample size is a significant limitation. These results suggest further assessment of changes in cognition during treatment through serial neuropsychological testing of glioma populations with defined marker status is warranted.

A-094 Isocitrate Dehydrogenase Status and Cognition in Glioma Patients

Objective In gliomas, isocitrate dehydrogenase-wildtype (IDH-wt) is associated with poorer prognosis and is correlated with lower brain connectivity, implicating cognitive impairment. Little is known about the impact of IDH-wt on cognition. This study aimed to explore the relationship between IDH-wt and cognition. Method Thirty-eight patients (Age M = 48.73 ± 14.98; 50% female) diagnosed with a glioma (29% grade II, 16% grade III, 21% grade IV; Karnofsky Performance Status score (KPS) M = 88.75 ± 14.24) were selected from a retrospective data cohort. 34.2% of patients had left hemisphere tumors, 34.2% of tumors were in the frontal lobes, and 15.8% were temporal lobe tumors. Patients were assessed via abbreviated neuropsychological battery following surgical resection prior to radiation and/or chemotherapy. Results The overall cognitive composite was not statistically significant via independent samples t-test (IDH-wt+: M = 42.37; IDH-wt-: M = 39.29; p = 0.897). Subdomains for attention/executive functioning (p = 0.625), memory (p = 0.923), and language (p = 0.501) were not significantly different. Logistic regression was conducted to investigate how IDH status predicts cognitive status. The coefficient has a Wald statistic equal to 0.042 which is not significant (critical value of 0.837) [df = 1]. Of those with IDH-wt+, 57% were impaired and 43% remained intact. Conclusion We did not find a significant association between IDH status and cognition though sample size is a significant limitation of the present study. More investigations are needed given it is possible that cognitive performance is related to IDH status and knowledge in this area could improve patient care/patient education.

A Comparative Study of Application Effects Between Coordinate Paper Positioning Assisted Probe Navigation and Probe Navigation in Glioma Surgery

Objective: To compare the effect of coordinate paper positioning assisted probe navigation and probe navigation in glioma surgery. Methods: 20 patients with glioma probe navigation coordinate paper positioning assisted probe navigation group (Test group). The patients were treated with probe navigation and coordinate paper positioning assisted probe navigation, respectively. Result: We made a comparison and found in the Test group was significantly reduced and the resection rate of tumors was significantly increased. The KPS (Karnofsky Performance Status) score in the Test group was significantly increased in 1–6 months. Conclusion: Compared with probe navigation, coordinate paper positioning assisted probe navigation is more effective in glioma surgery, which is worthy of clinical promotion.

MRI-guided cryoablation for metastatic spine disease: intermediate-term clinical outcomes in 14 consecutive patients

OBJECTIVEMinimal access ablative techniques have emerged as a less invasive option for spinal metastatic disease reduction and separation from neural tissue. Compared with heat-based ablation modalities, percutaneous image-guided cryoablation allows for more distinct visualization of treatment margins. The authors report on a series of patients undergoing MRI-guided cryoablation as a feasible method for treating spinal metastatic disease.METHODSA total of 14 patients with metastatic spine disease undergoing MR-monitored cryoablation were prospectively enrolled. Procedures were performed in an advanced imaging operating suite with the use of both CT and MRI to gain access to the spinal canal and monitor real-time cryoablation.RESULTSThe average age was 54.5 years (range 35–81 years). The mean preoperative Karnofsky Performance Status score was 79.3 (range 35–90). The average radiographic follow-up was 7.1 months (range 25–772 days), and the average clinical follow-up was 9.8 months (range 7–943 days). In 10 patients with epidural disease, 7 patients underwent postprocedural imaging, and of these 71% (5/7) had stable or reduced radiographic disease burden. Bone regrowth was observed in 63% (5/8) of patients with bone ablation during the treatment who had postoperative imaging. Pre- and postoperative visual analog scale scores were obtained, and a significant reduction in these scores was found following ablation. There were no complications.CONCLUSIONSMR-guided cryoablation is a minimally invasive treatment option for metastatic spine disease. In patients with epidural disease, the majority experienced tumor reduction or arrest at follow-up. In addition, pain was significantly improved following ablation. The average hospital stay was short, and the procedure was safe in a range of patients who are otherwise not ideal candidates for standard treatment.

Predictors of early postoperative epileptic seizures after awake surgery in supratentorial diffuse gliomas

OBJECTIVEFunctional-based resection under awake conditions had been associated with a nonnegligible rate of intraoperative and postoperative epileptic seizures. The authors assessed the incidence of intraoperative and early postoperative epileptic seizures after functional-based resection under awake conditions.METHODSThe authors prospectively assessed intraoperative and postoperative seizures (within 1 month) together with clinical, imaging, surgical, histopathological, and follow-up data for 202 consecutive diffuse glioma adult patients who underwent a functional-based resection under awake conditions.RESULTSIntraoperative seizures occurred in 3.5% of patients during cortical stimulation; all resolved without any procedure being discontinued. No predictor of intraoperative seizures was identified. Early postoperative seizures occurred in 7.9% of patients at a mean of 5.1 ± 2.9 days. They increased the duration of hospital stay (p = 0.018), did not impact the 6-month (median 95 vs 100, p = 0.740) or the 2-year (median 100 vs 100, p = 0.243) postoperative Karnofsky Performance Status score and did not impact the 6-month (100% vs 91.4%, p = 0.252) or the 2-year (91.7 vs 89.4%, p = 0.857) postoperative seizure control. The time to treatment of at least 3 months (adjusted OR [aOR] 4.76 [95% CI 1.38–16.36], p = 0.013), frontal lobe involvement (aOR 4.88 [95% CI 1.25–19.03], p = 0.023), current intensity for intraoperative mapping of at least 3 mA (aOR 4.11 [95% CI 1.17–14.49], p = 0.028), and supratotal resection (aOR 6.24 [95% CI 1.43–27.29], p = 0.015) were independently associated with early postoperative seizures.CONCLUSIONSFunctional-based resection under awake conditions can be safely performed with a very low rate of intraoperative and early postoperative seizures and good 6-month and 2-year postoperative seizure outcomes. Intraoperatively, the use of the lowest current threshold producing reproducible responses is mandatory to reduce seizure occurrence intraoperatively and in the early postoperative period.

Cabozantinib real-world effectiveness in the first through fourth-line settings for the treatment of metastatic renal cell carcinoma (mRCC): Results from the International mRCC Database Consortium (IMDC).

639 Background: Cabozantinib (Cabo) is approved for mRCC patients based on the METEOR and CABOSUN trials. The real-world effectiveness of Cabo in mRCC patients in the first- (1L), second- (2L), third- (3L) and fourth-line (4L) settings requires characterization. Methods: This retrospective analysis included mRCC patients who were treated with Cabo and stratified using IMDC risk groups. Overall response rate (ORR), time to treatment failure (TTF), and overall survival (OS) were calculated. Results: A total of 413 patients (82.6% with clear cell and 17.4% non-clear cell) were identified. The median age was 57 years. Overall, 63% of patients had a Karnofsky performance status score of >80 and 82.6% had prior nephrectomy. 23.1%, 75.4% and 88.3% of patients received immunotherapy as a prior line of treatment, before receiving Cabo in the 2L, 3L and 4L settings, respectively. For patients treated with 1L PD(L)1 combination or monotherapy (n=31), 2nd line Cabo had ORR of 20.8%, median TTF of 5.4 months and median OS of 17.4 months. When segregated into IMDC favorable, intermediate, and poor risk groups, the median OS was 34.8 months (95% CI 5.52-NR), 18.0 months (12.3-35.6) and 9.8 months (7.4-20.8), p=0.0088, respectively for 2L Cabo; and 31.5 months (23.6-39.3), 20.5 months (10.1-21.8), and 6.9 months (4.1-10.9), p=<0.0001), respectively for 3L Cabo. Conclusions: The ORR and TTF of Cabo were maintained from the 1L to the 4L therapy settings. In the 2L and 3L settings, the IMDC criteria appropriately stratified patients into favorable, intermediate and poor risk groups for OS. Cabo has activity after first line immunotherapy.[Table: see text]