Tumor-treating Fields Research Articles

Tumor treating field (TTF) therapy

TTF therapy is a type of electric field therapy that uses low-intensity electric fields to suppress cancer cell proliferation. It generates electric fields in the human body which interfere with rapid cell division in cancer cells, triggering apoptosis (cell death) locally or in a partial region. This treatment is over a decade old.

SURG-50. CLINICAL EXPERIENCE AND PATHOLOGICAL FEATURES IN AUTOPSY CASES TREATED WITH TUMOR TREATING FIELDS

Abstract BACKGROUND Since 2017 Tumor Treating Fields (TTF) was approved for primary glioblastoma in Japan. In this study, we reviewed clinical experience and the pathological characteristics of autopsy cases treated with TTF. METHODS From March 2018 to April 2022, 67 patients (36 males and 31 females, median age 68 years) with primary glioblastoma, IDH-wild type treated at our institution were included in the analysis. RESULTS Twenty-eight patients (19 males and 9 females, median age 66 years) met the TTF indication criteria for induction, 19 cases (67.9%) were 65 years or older, and 14 cases (50.0%) indicated MGMT promoter methylation. The mean duration of TTF treatment was 7.2 months. The main reasons for discontinuation were tumor recurrence in 11 patients (40.7%), skin symptoms in 8 patients (29.6%), and psychological distress in 6 patients (22.2%). Only 12 patients (42.9%) underwent TTF treatment over 18 hours per day, because of discomfort of wearing pad and concern about srrounding. Median PFS and OS in the used patients were 9.9 and 17.7 months, respectively. Autopsies were performed in 3 of the 16 deaths. Histopathological examination of tumor specimen indicate that the Ki-67 labeling index was higher in brainstem (33.6%) than in the supratentorial primary lesion (23.6%). DISCUSSION Comparing to the previous report (Stupp R et al., JAMA. 2017), our cases contained a large number of patients over 65 years old with shorter mean duration of TTF treatment, and shorter OS. After TTF treatment, the Ki-67 labeling index was higher on infratentorial than on supratentorial in the autopsy specimens, suggesting the anti-tumor effect of TTF for the supratentorial lesion. RESULTS High proliferative activity of infratentrial lesion was suggested as a typical form of progression for TTF treatment.

CTNI-81. PROPOSAL FOR A PHASE IB PILOT CLINICAL TRIAL TO STUDY SAFETY AND IMPROVING ANTI-NEOPLASTIC ADVERSE EFFECTS BY ADDITION OF NATURAL MARINE PRODUCT FUCOIDAN TO THE STANDARD THERAPY FOR PATIENTS WITH NEWLY DIAGNOSED GLIOBLASTOMA (GBM)

Abstract INTRODUCTION GBM is the most aggressive primary brain tumor. Despite standard of care (SOC) with the Stupp protocol and tumor treating fields (TTFs), survival remains poor. In addition, SOC treatment is associated with 96% any adverse effects (AE) and 25% severe AEs (Chinot et al, NEJM 2014), which affects quality of life (QOL) and can lead to early treatment termination. Therefore, novel therapies are needed and minimization of chemoradiation-related AEs is crucial. Marine natural product, fucoidan, may have an important role in oncological management as tumor-directed therapy and as a protectant against chemoradiation-related AEs. Fucoidan is a seaweed-derived sulfated polysaccharide. Mounting evidence garnered from randomized clinical trials for colon, head and neck, and lung cancer patients suggests that fucoidan can improve certain AEs associated with chemoradiation. Furthermore, data gleaned from multiple studies have shown that fucoidan is tolerable with a good safety profile. HYPOTHESIS Fucoidan is safe in combination with chemoradiation and chemotherapy and improves treatment related AE profile. Fucoidan may improve survival outcome in GBM patients by augmenting cytotoxic effects, inhibiting angiogenesis, and improving the tolerability of SOC therapy. METHOD 12 newly diagnosed GBM patients will be enrolled. A Fucoidan-based product will be administered orally at the established dose for cancer patients daily with concurrent chemoradiation therapy and adjuvant chemotherapy over 6 months. Patients will be evaluated weekly to monthly for AEs and QOL scoring; laboratory and brain MRI monitoring will be performed per SOC guidelines. NK cell activity, proinflammatory cytokines, including interleukin (IL)-1β, will be measured. POTENTIAL OUTCOME This pilot study may establish a foundation for future larger randomized clinical trials to treat brain cancer more effectively by adding nature products.

SURG-27. DIRECTIONALLY NON-ROTATING ELECTRIC FIELD THERAPY (DNEFT) DELIVERED THROUGH IMPLANTED ELECTRODES: A NOVEL SURGICAL PLATFORM FOR GLIOBLASTOMA IMMUNOTHERAPY

Abstract BACKGROUND While directionally rotating Tumor Treating Fields (TTF) therapy has garnered considerable clinical interest in recent years, there has been comparatively less focus on directionally non-rotating electric field therapy (dnEFT). OBJECTIVE Here, we explore dnEFT generated through implanted electrodes as a glioblastoma therapeutic platform, with the goal of facilitating clinical translation. METHODS Using custom-designed electrode arrays to study the effect of dnEFT using in vitro and in vivo glioblastoma models. RESULTS In vitro, dnEFT generated using a clinical grade spinal cord stimulator showed anti-neoplastic activity against independent glioblastoma cell lines. In support of the results obtained using the clinical grade electrode, dnEFT delivered through a customized, two-electrode array induced glioblastoma apoptosis. To characterize this effect in vivo, a custom-designed four-electrode array was fabricated such that tumor cells can be implanted into murine cerebrum through a center channel equidistant from the electrodes. After implantation with this array and luciferase expressing murine GL261 glioblastoma cells, mice were randomized to dnEFT or placebo. Relative to placebo treated mice, dnEFT reduced tumor growth (measured by bioluminescence) and prolonged survival (median survival gain of 6.5 days). Analysis of brain sections following dnEFT showed a notable increase in the accumulation of peri-tumoral macrophage/microglia with increased expression of M1 genes (IFNγ, TNFα, IL-6) and decreased expression of M2 genes (CD206, Arg, IL-10) relative to placebo tumors. CONCLUSIONS Our results suggest therapeutic potential in glioblastoma for dnEFT delivered through implanted electrodes as a novel immunotherapy platform, supporting the concept of a proof-of-principle clinical trial using commercially available deep brain stimulator electrodes.

CSIG-04. ANTI-TUMOR RESPONSE OF ONCOMAGNETIC MONOTHERAPY IN GLIOBLASTOMA

Abstract BACKGROUND Glioblastoma (GBM) is the most lethal primary malignant brain tumor with a median survival of 15–20 months. Concurrent temozolomide (TMZ) chemotherapy and radiation (XRT) remain the current standard of care (SOC) treatment for newly diagnosed GBM. The addition of tumor treating fields (TTFs) improves median survival for newly diagnosed GBM from 16 to 20.9 months. This modest improvement underscores the urgent need to identify a new treatment modality as a safe and effective therapy. PURPOSE The noninvasive Oncomagnetic device developed in our laboratory selectively kills glioblastoma (GBM) in vitro. We studied the cellular and molecular effects of Oncomagnetic monotherapy (OMT) on GBM cell lines and investigated immune response in a syngeneic mouse model. RESULTS OMT significantly reduces cell proliferation and cell survival in vitro. OMT induces persistent ROS primarily by increasing superoxide level in cancer cells and reduces mitochondrial-membrane potential in GBM cells. It also induces DNA damage and arrests cells in G1-phase of the cell cycle. Whole-body Oncomagnetic stimulation caused a substantial retardation of tumor growth and reduction of the contrast-enhanced tumor volume in 9.4T MRI scans. OMT showed significant increase in overall survival in treated mice. We also observed upregulated immune response indicated by RNA sequencing data obtained from OMT-treated GBM cells as well as in treated GBM mouse tumor sections by imaging mass cytometry analysis. The tSNE analysis of various immune clusters suggests significant increase in immune response by activating CD4+, CD8+, murine-macrophages and M1-macrophages located at tumor site in the treated group. CONCLUSION The obtained data indicate significant anti-tumor response by inhibiting cancer signaling pathways and an increased immune response. Our findings suggest unique mechanism of action for OMT stimulation and provide a strong rationale for standalone OMT for GBM.

CTNI-57. REAL-WORLD EVIDENCE OF THE FREQUENCY OF POST-SURGICAL INITIAL OBSERVATION IN PATIENTS WITH IDH-MUTANT GLIOMA

Abstract BACKGROUND After initial resection of IDH-mutant gliomas, initial observation is an option for low-risk patients, to postpone potential therapy-related toxicities without impacting survival. Since NCCN guidelines for risk stratification are considered controversial, we aimed to assess the frequency of initial observation in IDH-mutant gliomas using real-world evidence in the US. METHODS We evaluated Optum claims from 2016-2021 of patients age ≥12 with ICD-10 codes for incident glioma. Since ICD-10 does not distinguish IDH-mutant from IDH-wild type (GBM) gliomas, we excluded patients with factors indicative of GBM (age>60/ hypofractionated RT/ carmustine wafer/ tumor-treating fields) to create a baseline cohort. We then evaluated the subgroup age <40 (<40 cohort), who have higher IDH-mutant incidence. To distinguish initial observation from surgical recovery, we assessed time from index surgery to first intervention. When 90% of first interventions had occurred those still without intervention were considered to undergo initial observation. RESULTS The baseline and <40 cohorts comprised 5404 and 646 patients, respectively. In the baseline cohort, 56% had intervention by day 90 (most commonly concurrent chemoradiation); peak intervention rate was 60%. Initial observation rate was 44%. In the <40 cohort, 47% had an intervention by day 90; peak intervention rate was 52%. Initial observation rate was 53%. CONCLUSIONS In both cohorts ≥90% of patients with likely IDH-mutant gliomas not initiating treatment within 3 months post-surgery continued in active observation. Initial observation rates were 44-53%, well above the levels we had expected based on NCCN guidelines. The cohorts likely include some GBM patients, for whom observation is unaccepted, and therefore these rates may understate actual initial observation rates for IDH-mutant glioma patients. These findings suggest that clinicians and patients have chosen initial observation over existing treatments, evincing a need for additional treatment options for this younger group of patients with considerably long life expectancy.

CTNI-25. TUMOR TREATING FIELDS (TTFIELDS) THERAPY WITH CHEMORADIATION, FOLLOWED BY MAINTENANCE TTFIELDS THERAPY/TEMOZOLOMIDE (TMZ), IN NEWLY DIAGNOSED GLIOBLASTOMA (NDGBM). RESULTS OF PHASE II CLINICAL STUDY

Abstract INTRODUCTION Tumor-Treating Fields (TTFields) are electric fields that exert physical forces to disrupt cancer cell function and tumor progression via a multimodal mechanism of action. Following the phase 3 pivotal EF-14 study, TTFields therapy concomitant with temozolomide (TMZ) maintenance therapy became approved for newly-diagnosed glioblastoma (ndGBM). Pre-clinical data and pilot clinical studies suggests synergistic effect of concomitant TTFields treatment with radiotherapy (RT). OBJECTIVE To assess the efficacy and safety of first line TTFields therapy concomitant with RT/TMZ vs RT/TMZ alone in adult patients with ndGBM. Design: 69 patients with ndGBM and KPS≥70 stratified by MGMT status, extent of resection, and age, were randomized 1:1. The experimental arm received TTFields therapy from the first day of chemoradiation, the control arm started 4 weeks after completion of chemoradiation. Patients continued TTFields therapy until second disease progression or 24months. The primary endpoint was 1-year PFS rate, and secondary endpoints included PFS, OS, and safety. Kaplan-Meier estimates were used to assess whether PFS and OS were improved with first line TTFields therapy/RT/TMZ vs RT/TMZ with delayed TTFields therapy. RESULTS Overall, 46 patients received maintenance chemotherapy and TTFields therapy. Mean age was 62 years (range:27–77). One-year PFS rate was 36% and 19% in the experimental and control arms, respectively (p-value=0.10). Median PFS was 9.9 and 5.6 months (HR 0.53, p-value 0.049). Median OS was 25.9 and 17 months (HR 0.85, p-value=0.6). Two-year OS rates were 52% and 31% (p-value 0.07). Among patients with high TTFields usage (≥75%) 2-year OS rates were 78% and 34% (p=0.01). CONCLUSIONS The addition of concomitant TTFields to standard treatment with temozolomide and RT for patients with ndGBM appears to be another step in improving the outcome of this patients population. This is further investigated in the large-scale TRIDENT study.

PATH-26. MIDLINE INVOLVEMENT IS ASSOCIATED WITH ABERRANT RB1 SIGNALING IN PATIENTS WITH GRADE 4 IDH-MUTANT ASTROCYTOMA

Abstract BACKGROUND The prognostic factors impacting the survival of grade 4 IDH-mutant astrocytoma treated with standard radiation/temozolomide are not well-described. METHODS A retrospective cohort was generated of all patients diagnosed at Mayo Clinic with grade 4 IDH-mutant astrocytoma (2021 WHO Classification) on initial diagnosis between 2002-2023, and who received standard radiation/temozolomide. The impact of patient, tumor and molecular variables on overall survival (OS) and progression-free survival (PFS) was evaluated using survival analyses and Cox regression models. RESULTS Fifty-eight patients were identified. The median age was 36 years, 64% were male and 93% were white. The median follow up was 3.3 years. The median OS and PFS were 6.9 years and 2.4 years, respectively. CDKN2A/B homozygous deletion significantly reduced both OS (2.5 years vs NR, HR=3.9, p=0.0168) and PFS (1.4 vs 4.5 years, HR=4.2, p=0.0005). Midline involvement (brainstem, basal ganglia, thalamus, cerebellum or corpus callosum) also significantly reduced both OS (2.4 vs 12.8 years, HR=7.0, p=0.0014) and PFS (1.4 vs 4.5 years, HR=4.8, p=0.0002). MGMT promoter hypermethylation showed a trend toward significance for PFS (p=0.082) but did not impact OS. Age, sex, tumor size, ATRX immunohistochemistry and tumor-treating field therapy did not impact survival outcomes. Multivariable analyses revealed that PFS remained significantly impacted by both CDKN2A/B homozygous deletion (HR=3.5, p=0.0051) and midline involvement (HR=3.1, p=0.0125). A significant association between CDKN2A/B homozygous deletion and midline involvement was unexpectedly observed (53% if midline, 24% if non-midline; χ2=4.3, p=0.037). Exploratory analyses revealed that 15/15 (100%) of patients with midline involvement demonstrated aberration in RB1 signaling (CDKN2A/B homozygous deletion, n=8; CDKN2A/B hemizygous deletion or loss of heterozygosity, n=6; CDK4 amplification, n=1). CONCLUSION CDKN2A/B homozygous deletion and midline involvement independently impact PFS in patients with grade 4 IDH-mutant astrocytoma treated with standard radiation/temozolomide. Furthermore, midline involvement may be associated with aberrant RB1 signaling.

CTNI-05. A PROSPECTIVE STUDY OF TUMOR-TREATING FIELDS COMBINED WITH SYSTEMIC THERAPY IN RECURRENT GLIOBLASTOMA

Abstract BACKGROUND Tumor-treating Fields (TTFields) monotherapy was approved for recurrent glioblastoma. However, TTFields combined with systemic therapy has not been well studied in China. This study aims to explore the efficacy and safety of such combination therapy for recurrent GBM. METHOD This study is a prospective, single-arm, open-label clinical trial (NCT04689087) planning to enroll 40 recurrent supratentorial GBM patients and use TTFields combined with physician chose systemic therapy. Kaplan-Meier survival curve was used to estimate PFS, OS and survival rate. The primary endpoint was 6-months OS rate (OS6). Secondary endpoints were PFS, PFS6 and safety. OS and PFS were computed from the day of initiating TTFields. RESULT Fourty recurrent supratentorial GBM patients was enrolled from July 2020 to May 2023. The average age was 51 and median KPS score was 80. Sixty-eight percent (27/40) of them underwent total resection surgery and 5% (2/40) only experienced biopsy as their newly diagnosed GBM surgery. Eighty-eight percent (35/40) of patients started TTFields when they were first diagnosed as recurrence, while 12.5% (5/40) patients started TTFields at their second-time recurrence or latter. Median time from diagnosis of recurrence to initiating TTFields was 27 days. Median duration time of TTFields was 8.7 months and average compliance of TTFields was 87% (20.9 hours/day). As for molecular biomarkers, 50% (20/40) patients were MGMT protein positive and 32.5% (13/40) were TERT mutant. Chemotherapy was included in the systemic therapy in 80% (32/40) patients, antiangiogenic therapy in 60% (24/40) patients, BRAF inhibitor therapy in one patient and immune checkpoint inhibitor therapy in one patient. At data cut-off date of March 20, 2024, the median follow-up period was 20.8 months. The primary endpoint OS6 was 87.2%, the median OS was 20.2 months (95%CI 11.9-NR). Median PFS was 8.5months (95%CI 6.2-NR). PFS6 was 67.5% while the historical reference of physician’s best choice of active chemotherapy from EF-11 study showed a PFS6 of 15%. Scalp adverse events were the most common AE. Seventy-eight (31/40) of patients experienced grade 1 or 2 scalp adverse events which can be relieved by topical corticosteroids. CONCLUSION TTFields combined with systemic therapy showed favorable efficacy and safety in Chinese recurrent GBM patients. Key words: Recurrent GBM, TTFields, prospective study, systemic therapy

Efficacy of Adding Veliparib to Temozolomide for Patients With MGMT-Methylated Glioblastoma

The prognosis for patients with glioblastoma is poor following standard therapy with surgical resection, radiation, temozolomide, and tumor-treating fields. To evaluate the combination of veliparib and temozolomide in glioblastoma based on preclinical data demonstrating significant chemosensitizing effects of the polyadenosine diphosphate-ribose polymerase 1/2 inhibitor veliparib when combined with temozolomide. Patients with newly diagnosed glioblastoma with MGMT promoter hypermethylation who had completed concomitant radiation and temozolomide were enrolled between December 15, 2014, and December 15, 2018, in this Alliance for Clinical Trials in Oncology trial. The data for this analysis were locked on April 21, 2023. Patients were randomized and treated with standard adjuvant temozolomide (150-200 mg/m2 orally, days 1-5) combined with either placebo or veliparib (40 mg orally, twice daily, days 1-7) for 6 cycles. The primary end point for the phase 3 portion of the trial was overall survival (OS). There were 322 patients randomized during the phase 2 accrual period and an additional 125 patients randomized to complete the phase 3 accrual, for a total of 447 patients in the final phase 3 analysis. The median (range) age for patients was 60 (20-85) years and 190 patients (42.5%) were female. The median OS was 24.8 months (90% CI, 22.6-27.7) for the placebo arm and 28.1 months (90% CI, 24.3-33.3) for the veliparib arm (P = .17). The difference in survival did not meet the prespecified efficacy end point. However, there was a separation of the survival curves that favored the veliparib arm over 24 to 48 months of follow-up. The experimental combination was well tolerated with an acceptable elevation in grade 3 or 4 hematologic toxic effects. This trial found that adding veliparib to adjuvant temozolomide did not significantly extend OS in patients with newly diagnosed, MGMT-hypermethylated glioblastoma. ClinicalTrials.gov Identifier: NCT02152982.

The Patterns of Failure and Prognostic Impact of Tumor Location in Patients Undergoing Reirradiation for Glioblastoma.

Introduction RTOG 1205 is the only randomized study to evaluate the safety and efficacy of reirradiation (reRT) in recurrent glioblastoma (GBM). While this study showed that reRT was safe and improves progression-free survival (PFS), an improved approach to reRT is still needed. In this study, we report on patterns of failure and outcomes in a cohort of patients with recurrent GBM who underwent reRT. We hypothesize that patients at high risk of leptomeningeal spread (LMS) are not good candidates for reRT due to the risk of treatment-related toxicity without clinical benefit. Methods In this retrospective study, patients with recurrent GBM who underwent reRT at a single institution from 2015-2023 were included. Sociodemographic, treatment, and outcomes data were collected via chart review. Time to progression was defined as the time from the start of reRT to progression per the Response Assessment in Neuro-Oncology (RANO) criteria. Overall survival (OS) was defined as the time from the start of reRT to death. PFS and OS were estimated using the Kaplan-Meier method. Results Thirteen patients with recurrent GBM who underwent reRT were identified. The median age at diagnosis was 58 years. Six patients (46.2%) had tumors that were O6-methylguanine-DNA methyltransferase (MGMT) methylated, four (30.8%) were MGMT unmethylated, and three (23.11%) had unknown MGMT status. Eight patients underwent repeat resection after recurrence and before reRT. Most patients (n=7) received 35 Gy in 10 fractions with concurrent bevacizumab, while other patients were treated with 25-40 Gy in 5-15 fractions with grade 1 or less acute toxicity. Three patients were treated with tumor-treating fields. The median follow-up was five months. Median PFS was three months [95% confidence interval (95% CI): one to four months] and median OS was five months (95% CI, 1-8 months) as compared to 7.1 months and 10.1 months, respectively, on RTOG 1205. Five patients developed LMS after reRT, one patient died before progression, and the remaining seven patients all developed progression within one centimeter of the recurrent tumor. Of the patients who developed LMS, all had tumors abutting the ventricles and three underwent resection 2-17 months before reRT. Conclusion Patterns of failure suggest a potential treatment selection approach for patients with recurrent GBM, in which patients at high risk of LMS (tumor abutting ventricles with or without recent surgery) should not undergo reRT, while patients at low risk of LMS are good candidates for reRT. Furthermore, reRT could be administered with reduced margins given that all non-LMS recurrences were within 1cm of the original tumor. Additional studies are needed to validate this approach.

Tumor-treating fields increase cytotoxic degranulation of natural killer cells against cancer cells

Tumor-treating fields increase cytotoxic degranulation of natural killer cells against cancer cells

Technical note: Computational study on thermal management schemes for tumor-treating fields therapy.

The study focuses on thermal management in tumor-treating fields (TTFields) therapy, crucial for patient compliance and therapeutic effectiveness. TTFields therapy, an established treatment for glioblastoma, involves applying alternating electric fields to the brain. However, managing the thermal effects generated by electrodes is a major challenge, impacting patient comfort and treatment efficiency. This research aims to explore methods for controlling temperature increases during TTFields therapy without reducing its duty cycle. The study emphasizes optimizing electrode configurations and array arrangements to mitigate temperature rise, thereby maintaining therapy effectiveness and patient compliance. Using a simplified multi-layer tissue model and finite element analysis, various electrode configurations and array shapes were tested in COMSOL Multiphysics v6.0. Adjustments included changing the electrode gel layer radius from 8 to 12mm, electrode spacing, and transitioning to a more uniform array arrangement, such as a square array or a circular array. The study revealed a strong correlation between high temperatures and edge current density distributions on electrodes. It was found that increasing the electrode gel layer's diameter, enlarging electrode spacing, and adopting a uniform array arrangement markedly mitigated temperature rises. By increasing the gel layer radius from the original 10 to 12mm, a reduction in the peak temperature increases of approximately 0.3°C was observed. Changing the layout from rectangular to circular with the same area further reduced the peak temperature rise by 0.5°C. Additionally, enlarging the spacing between electrodes also contributed to temperature control. By integrating these strategies, we designed a new circular electrode array with an electrode spacing of 45mm and a gel radius of 12mm, successfully reducing the peak temperature from 42.1°C to 40.8°C, effectively achieving temperature control. The research demonstrates that improving electrode and array configurations can effectively manage temperature in TTFields therapy without compromising treatment duration. This strategy is crucial as TTFields therapy relies on prolonged field exposure for effectiveness. The findings offer valuable insights into thermal management in electrode array design and could lead to enhanced patient compliance and treatment efficacy in TTFields therapy.

Improving Glioblastoma Multiforme Recurrence Prediction through Integrated Radiomics and Deep Learning Techniques

Glioblastoma multiforme (GBM) is one of the most lethal forms of brain cancer, with a five-year survival rate of only 4% to 5%. The recurrence rate is alarmingly high, reaching up to 90%. While tumor-treating fields have shown potential in extending survival, their efficacy in treating recurrent GBM remains limited. This study aims to leverage Deep Learning (DNN) to predict the recurrence of GBM in patients, both pre- and post-surgery. Utilizing advanced computational techniques, this research employs radiomics to analyze brain tumor images, aiding clinicians in identifying tumor spread, predicting post-surgical recurrence, and estimating patient survival. Pre-surgery, Multi-Parametric Magnetic Resonance Imaging (MP-MRI) scans are used to detect tumor locations and forecast potential recurrences. To enhance image processing, Z-score normalization and spatial resampling are applied. Additionally, a model was developed to address the issue of imbalanced data in medical imaging. The study utilized Contrast-Enhanced T1-Weighted Imaging (CE-T1WI) MRI to assess treatment effectiveness and predict recurrence-free survival. A Deep Neural Network was trained to forecast tumor recurrence, identifying patients at risk of early recurrence. Feature extraction from brain images was performed using the Inheritable Bi-Objective Combinatorial Genetic Algorithm. The accuracy of the recurrence predictions was validated and compared against other models, including CNN Inception-V3, CNN AlexNet, and VGG16, using the Python programming language. Results indicate that the proposed method surpasses existing techniques by 3%, 4%, and 5% in accuracy, specificity, and sensitivity, respectively. This research demonstrates that in a retrospective patient population, predictions of patient survival and time to recurrence exhibit high sensitivity, specificity, and accuracy, offering a promising tool for improving GBM management and patient outcomes.

Revisiting the standards of cancer detection and therapy alongside their comparison to modern methods.

In accordance with the World Health Organization data, cancer remains at the forefront of fatal diseases. An upward trend in cancer incidence and mortality has been observed globally, emphasizing that efforts in developing detection and treatment methods should continue. The diagnostic path typically begins with learning the medical history of a patient; this is followed by basic blood tests and imaging tests to indicate where cancer may be located to schedule a needle biopsy. Prompt initiation of diagnosis is crucial since delayed cancer detection entails higher costs of treatment and hospitalization. Thus, there is a need for novel cancer detection methods such as liquid biopsy, elastography, synthetic biosensors, fluorescence imaging, and reflectance confocal microscopy. Conventional therapeutic methods, although still common in clinical practice, pose many limitations and are unsatisfactory. Nowadays, there is a dynamic advancement of clinical research and the development of more precise and effective methods such as oncolytic virotherapy, exosome-based therapy, nanotechnology, dendritic cells, chimeric antigen receptors, immune checkpoint inhibitors, natural product-based therapy, tumor-treating fields, and photodynamic therapy. The present paper compares available data on conventional and modern methods of cancer detection and therapy to facilitate an understanding of this rapidly advancing field and its future directions. As evidenced, modern methods are not without drawbacks; there is still a need to develop new detection strategies and therapeutic approaches to improve sensitivity, specificity, safety, and efficacy. Nevertheless, an appropriate route has been taken, as confirmed by the approval of some modern methods by the Food and Drug Administration.

DIPG-40. LONG TERM SURVIVAL OF A 14 YEAR OLD GIRL WITH H3K27M MUTATED DIFFUSE MIDLINE GLIOMA FOLLOWING RADIOTHERAPY AND PROLONGED TUMOR TREATING FIELDS (TTFIELDS) -CASE REPORT

Abstract INTRODUCTION Pediatric diffuse midline H3K27M mutated glioma has a dismal prognosis. Most cases are treated by radiotherapy and oral chemotherapy, with surgical resection having a debatable role in some. Tumor-treating fields (TTFields) is a noninvasive modality in which alternating electrical fields exert biophysical force on charged and polarizable molecules known as dipoles. TTFields has been shown to extend survival for adult patients with newly diagnosed and recurrent GBM, and is FDA approved for these indications. There is sparse data about pediatric patients. CASE REPORT A 14-year-old girl presented with headache and vomiting. A large left thalamic tumor was diagnosed and underwent subtotal resection. Diagnosis was diffuse midline glioma, H3K27M positive, IDH negative. Molecular Panel: Tumor mutation burden low, microsatellite stable. Genomic findings: FGFR1, NF1, H3F3A -K28M, ATRX R666, MAP3K1 She was re-operated due to a fast tumor relapse within a few weeks, prior to radiotherapy, followed with radiotherapy with local field 59Gy. She then received temozolamide (12 months) concomitant with TTfields (Optune, Novocure). TTfields therapy was administered for 5 years without adverse effects and excellent compliance (above 85%). After 5 years, therapy was withheld, and she is now off therapy NED for another 15 months. DISCUSSION Diffuse midline H3K27M glioma harbors a poor prognosis in children. Children refrain from this treatment both for lack of evidence and because of the difficulty in adhering to a regimen that demands carrying a battery of 1.5-2kg all day and shaving all hair every 3 days. Our patient had a high compliance and as she wore a head scarf for religious customs, the device was not visible. To our knowledge this is the first pediatric reported case of long-term survival of H3K27mutatted midline glioma using TTFields. Further pediatric studies are warranted.

Tumor-treating fields in cancer therapy: advances of cellular and molecular mechanisms.

Tumor-Treating Fields (TTFields) use intermediate-frequency and low-intensity electric fields to inhibit tumor cells. However, their mechanisms are still not well understood. This article reviews their key antitumor mechanisms at the cellular and molecular levels, including inhibition of proliferation, induction of death, disturbance of migration, and activation of the immune system. The multifaceted biological effects in combination with other cancer treatments are also summarized. The deep insight into their mechanism will help develop more potential antitumor treatments.

HRQoL in patients with GBM: The impact of tumor treating fields.

e24049 Background: Glioblastoma (GBM) is the most common malignant glioma with a dismal prognosis. Patients experience a range of progressively worsening symptoms, including headaches, nausea, seizures, and cognitive deficits throughout their disease course. Initial treatment for newly diagnosed patients consists of maximal safe surgical resection followed by fractionated radiation treatment with concomitant temozolomide. Presently, there are two approved adjuvant treatment modalities following chemoradiation: temozolomide and tumor-treating fields (TTFields). In this poster, we explore the impact of TTFields on the quality of life, assessed through health-related quality of life (HRQoL), in patients with GBM. Methods: Using PubMed, Medline-indexed articles were collected using this structured query: Glioblastoma[MeSH] AND (("Electric Stimulation Therapy*"[MeSH]) OR ("Transcranial Direct Current Stimulation*"[MeSH]) OR "Tumor Treating Fields" OR "TTF") NOT "RAT" This yielded 233 results before the search date (2023). Collected sources were uploaded to Covidence to allow for multi-reviewer screening, review, and extraction. For completeness, limited forward and back citations using the ResearchRabbit tool and limited addition of non-Medline indexed articles via unstructured query yielded four additional results. Sources were filtered by study type and included/excluded based on accessibility, sample population, design, outcome measures, and interventions. Five randomized control studies remained. From this subset, bias, effect size, I2-index, and forest analysis with random effect model estimation were calculated. Results: Data analysis showed that TTFields therapy has demonstrated associations with increased progression-free survival and enhanced overall survival rates without negative effects on HRQoL. Some patients have reported improvement in mobility, self-care, and carrying out regular activities. One notable side effect observed in these patients was increased skin itchiness, which was expected due to the use of transducer arrays. Conclusions: This project identified a research gap in standardizing the assessment of quality of life in patients treated with TTFields. A significant limitation in research on TTFields is an overall lack of HRQoL data, often due to patients failing to follow-up with surveys. Future research should prioritize patient follow-up to obtain more comprehensive and precise longitudinal data on HRQoL while considering disease and treatment characteristics.

Prognostic factors of grade 4 IDH-mutant astrocytoma.

e14019 Background: The data on the prognostic factors of grade 4 IDH-mutant astrocytoma remains limited since the 2021 update of the WHO classification of Central Nervous System tumors. This update recognizes the importance of molecular characteristics and confers a grade 4 diagnosis based on the presence of at least one of either necrosis, microvascular proliferation, or CDKN2A/B homozygous deletion. This study sought to determine the factors that impact prognosis of patients with grade 4 IDH-mutant astrocytoma. Methods: A retrospective review was performed on all patients diagnosed with grade 4 IDH-mutant astrocytoma on initial diagnosis (as defined by the 2021 WHO classification) across the three Mayo clinic campuses (Minnesota, Florida, Arizona) between 2002 and 2023. Datapoints collected included demographic, clinical, imaging, histological and molecular variables. Factors impacting survival outcomes (overall survival [OS] and progression free survival [PFS]) were evaluated using Cox regression models. Results: Sixty-two patients with grade 4 IDH-mutant astrocytoma were identified (43 based on histological criteria alone, 10 based on molecular criteria alone, and 9 based on both). The median age of the patients was 36 years, with 64.5% of the patients identified as male and 93.3% as white. 100% (n=58) of these patients received standard treatment after surgery (radiation/temozolomide). The median follow up was 3.3 years. The median PFS and OS were 3.2 and 6.9 years, respectively. The OS was impacted by an unfavorable tumor location (either tumor involving the midline or at least 3 brain lobes; 2.4 years vs. 12.8 years, HR 10.8 [95% CI 3.29-35.6], p<0.001) and CDKN2A/B homozygous deletion (2.5 years vs. NR, HR=4.3 [95% CI 1.5-12.3], p=0.0065). The PFS was impacted by an unfavorable tumor location (1.4 years vs. 4.6 years, HR=5.3 [95% CI 2.21-12.7], p=0.002), CDKN2A/B homozygous deletion (1.4 years vs. 4.6 years, HR=6.2 [95% CI 2.71-14.2], p<0.001) and MGMT promoter hypermethylation (4.6 years vs. 1.4 years, HR=0.369 [95% CI 0.154-0.883], p=0.025). Age, sex, tumor size and the use of tumor-treating fields did not significantly affect survival outcomes. Using multivariable analyses, PFS remained significantly impacted by CDKN2A/B homozygous deletion (HR=11.3 [95% CI 3.23-39.0], p=0.0001) and MGMT promoter hypermethylation (HR=0.243 [95% CI 0.082-0.717], p=0.0104), but not by an unfavorable tumor location (p=0.819). Conclusions: Both CDKN2A/B homozygous deletion and MGMT status may independently influence the progression-free survival of patients with grade 4 IDH-mutant astrocytoma.

Revolutionizing Glioblastoma Treatment: A Comprehensive Overview of Modern Therapeutic Approaches.

Glioblastoma is the most common malignant primary brain tumor in the adult population, with an average survival of 12.1 to 14.6 months. The standard treatment, combining surgery, radiotherapy, and chemotherapy, is not as efficient as we would like. However, the current possibilities are no longer limited to the standard therapies due to rapid advancements in biotechnology. New methods enable a more precise approach by targeting individual cells and antigens to overcome cancer. For the treatment of glioblastoma, these are gamma knife therapy, proton beam therapy, tumor-treating fields, EGFR and VEGF inhibitors, multiple RTKs inhibitors, and PI3K pathway inhibitors. In addition, the increasing understanding of the role of the immune system in tumorigenesis and the ability to identify tumor-specific antigens helped to develop immunotherapies targeting GBM and immune cells, including CAR-T, CAR-NK cells, dendritic cells, and immune checkpoint inhibitors. Each of the described methods has its advantages and disadvantages and faces problems, such as the inefficient crossing of the blood-brain barrier, various neurological and systemic side effects, and the escape mechanism of the tumor. This work aims to present the current modern treatments of glioblastoma.