Radiation necrosis (RN) is a potential complication after radiation therapy for brain tumors. It is hypothesized that VEGF plays an important role in the pathophysiology of RN. Bevacizumab, a monoclonal antibody against VEGF-A, is often successful in the management of RN. The objective of this study is to assess whether VEGF receptor (VEGFR) inhibitors, a group of oral tyrosine kinase inhibitors (TKIs), can prevent or reverse RN.We retrospectively studied a cohort of 102 patients with renal cell carcinoma and brain metastases seen at The Ohio State University James Cancer Center between January 1, 2011 and April 30, 2019. We identified those who developed RN and analyzed the temporal relationship between the use of VEGFR TKIs and the development of RN.The cumulative incidence of RN is 13.7% after radiation treatments that included LINAC-based stereotactic radiosurgery, fractionated stereotactic radiotherapy, or Gamma Knife radiosurgery. There was no statistically significant difference in the cumulative incidence of RN between patients taking TKIs and patients who were off TKIs (9.9% and 11.5% respectively, P = .741). The median time to development of RN was only numerically shorter in patients taking TKIs (151 vs 315 days, P = .315). One patient developed RN after stopping cabozantinib. Eight patients developed RN while on cabozantinib, pazopanib, or sunitinib. One patient was started on axitinib during active RN without significant improvement subsequently.VEGFR TKIs do not consistently prevent RN. The therapeutic effects of VEGFR TKIs against RN warrant further research.
Record matching is an important process in data integration and data cleaning. It involves identifying cases where multiple database entities correspond to the same realworld entity. Often, duplicate records do not share a common key and contain erroneous data that make record matching a difficult task. The quality of a record matching system highly depends on a good approach that is able to accurately detects duplicates in an efficient and effective way. Despite the many techniques that have been introduced over the decades, it is unclear which technique is the current state-of-the-art. Hence, the objectives of this project are: 1. Compare a few record matching techniques and evaluate their advantages and disadvantages. 2. Develop a technique that combines the best features from these techniques to produce an improved record matching technique. Currently, there are two main approaches for duplicate record detection, categorised into approaches that rely on training data, and approaches that rely on domain knowledge or distance metrics. This project focuses on comparisons between the Probabilisticbased approach from the former category, and the Rule-based approach from the latter category. For the Probabilistic-based approach, instead of relying on training data, we employed the Expectation Maximization (EM) algorithm to find maximum likelihood estimates of parameters in the Probabilistic models. Our experimental study reveals that the Probabilistic-based approach, employing the EM algorithm, yields better results than the Rule-based approach when the requirements to generate the Probabilistics parameters are satisfied. Another reason for the poor results from the Rule-based approach is due to the lack of domain knowledge when manually crafting the ruleset. We believe that the Rule-based approach may perform well, given substantial manual effort and time to fine-tune the rules. However, extensive manual analysis of the dataset is not desirable. To this end, we propose an approach that leverages statistics computed from the EM algorithm to automatically derive a better ruleset for the Rule-based approach. Our experimental study shows that the proposed approach performs very well, even exceeding the performance of the Probabilistic-based approach.
Glioblastoma (GBM) is an aggressive primary brain tumor that is associated with a poor prognosis and quality of life. The standard of care has changed minimally over the past two decades and currently consists of surgery followed by radiotherapy (RT), concomitant and adjuvant temozolomide, and tumor treating fields (TTF). Factors such as tumor hypoxia and the presence of glioma stem cells contribute to the radioresistant nature of GBM. In this review, we discuss the current treatment modalities, mechanisms of radioresistance, and studies that have evaluated promising radiosensitizers. Specifically, we highlight small molecules and immunotherapy agents that have been studied in conjunction with RT in clinical trials. Recent preclinical studies involving GBM radiosensitizers are also discussed.
TPS2065 Background: The prognosis for patients (pts) with recurrent (r) glioblastoma (GBM) is poor, with no highly effective approved therapies. Treatment failure may result from poor penetration of drugs through the blood-brain barrier and the immunosuppressive nature of the tumor microenvironment (TME). PVSRIPO, a recombinant poliovirus (PV):rhinovirus chimera, is a novel, non-neurovirulent, intratumoral immunotherapy. Trial results in rGBM pts show greater long-term survival with PVSRIPO monotherapy (21%, 36-60 months [mos]) vs criteria-matched external controls (4%, 36 mos; 2%, 60 mos; Desjardins 2018 NEJM). PVSRIPO targets CD155 (PV receptor), expressed on solid tumors and on APC. PVSRIPO infection results in inflammatory-mediated destruction of tumor cells but non-lethal lingering infection in TME APC. This leads to type I/III interferon-dominant inflammation and, ultimately, tumor antigen-specific T cell activation and recruitment (Brown 2017 Sci Transl Med), which is potentiated by immunologic recall to intratumoral replicating virus via prior vaccination. Induction of type 1 IFN dominant inflammation and compensatory activation of the PD-1:PD-L1 immune checkpoint (IC) pathway support investigation of PVSRIPO in combination with PD-1/L1 IC inhibitors. Immunologically cold mouse glioma models show PVSRIPO+anti-PD-1 therapy resulted in greater anti-tumor response than either agent. Methods: LUMINOS-101 is a phase 2, multicenter, open-label, single-arm study of intratumoral infusion of PVSRIPO (Day 1: 5x10 7 TCID 50 ) followed by the anti-PD-1 monoclonal antibody pembrolizumab (200mg IV q3w) in adult pts with rGBM. The trial objective is to evaluate anti-tumor activity and safety and tolerability of the combination. Eligibility criteria include pts ≥18 years who had prior PV and boost IPOL ® immunizations, histologically confirmed supratentorial rGBM, infusible 1 to ≤5.5cm enhancing disease, confirmed disease progression following prior therapies, and KPS ≥70. Key exclusion criteria include multifocal disease; discontinuation of prior anti-PD-1/L1 agent for toxicity; prior intratumoral therapy, immunotherapy, or radiotherapy within 12 weeks; high-dose systemic corticosteroids; chemotherapy, anti-VEGF, or TTF therapy ≤1-6 weeks depending on the therapy; serious cerebral herniation syndrome; extensive leptomeningeal, subependymal, or ≥1cm enhancing disease crossing the midline; and severe active comorbidities. Primary endpoints are objective response rate, duration of response, and safety. Secondary endpoints include overall and progression-free survival and disease control rate and duration. Exploratory endpoints include assessment of tumor and blood for biomarkers of response. The initially planned safety lead-in period is now fully enrolled. Recruitment is ongoing in the US, and results will inform the design of a randomized phase 3 trial. Clinical trial information: NCT04479241.
Abstract INTRODUCTION While advocacy for inmates with cancer has recently gained momentum, little is known about management of brain tumors in inmates. Delays in acknowledging or recognizing nonspecific initial symptoms can lead to delayed diagnosis and treatment. Inmates with cancer are reported to either be ignored or receive substandard care due in part to cost or logistics (American Civil Liberties Union; ASCO Post 2018). METHODS In this retrospective study, we identified inmates with gliomas seen in the Ohio State University Neuro-oncology Center between 1/1/2010-4/20/2019. RESULTS Twelve patients were identified. Median age at presentation was 39.5 years (range 28-62). Eleven patients were Caucasian and one was African American. Diagnoses included glioblastoma (GBM) (n=6), anaplastic astrocytoma (n=1), anaplastic oligodendroglioma (n=1), low-grade astrocytoma (n=3) and anaplastic pleomorphic xanthroastrocytoma (n=1). Patients were more likely to present early after seizures or focal neurologic deficits (9/12) than after headaches alone. Patients with GBM started RT 12-71 days after surgery (median 34.5). One patient’s post-RT MRI was delayed by a month and another with GBM had treatment held after 4 cycles of adjuvant temozolomide (TMZ) due to “incarceration issues”. For one patient who received adjuvant TMZ, the facility failed to communicate with the primary team throughout treatment. Two patients suffered significant nausea while on chemotherapy due to inability to obtain ondansetron in prison, or due to wrong timing. 7/12 (58%) patients were lost to follow-up for periods of 3-15 months during treatment. Three patients refused adjuvant treatment. CONCLUSIONS Although this is a small series, our results highlight the inequities and challenges faced by inmates with gliomas who are more likely to forego treatments or whose incarceration prevents them from keeping appropriate treatment and follow-up schedules. Additional studies are needed to define and address these deficiencies in the care of inmates with brain tumors and other cancers.
Abstract BACKGROUND DNX-2401 (tasadenoturev) is a replication-competent, tumor-selective, oncolytic adenovirus. Phase I studies in adults with recurrent glioblastoma (rGBM) have demonstrated safety and encouraging clinical activity. A Phase II open-label, dose-escalating multi-center study in rGBM was initiated to evaluate DNX-2401 with pembrolizumab. Planned enrollment of 48 subjects is complete. METHODS Subjects ≥ 18 years, with a single tumor, KPS ≥ 70% and adequate organ function were enrolled sequentially into 3 cohorts of DNX-2401 (5e8vp, 5e9vp, 5e10vp). A single intratumoral injection of DNX-2401 was administered followed 7 days later by pembrolizumab (200 mg IV). Thereafter, pembrolizumab was infused Q3wks up to 24 months until progression or toxicity. 5e10vp was determined as the optimal dose and this cohort was expanded. Safety monitoring, assessments of response and survival follow-up are ongoing. RESULTS Nine subjects were treated in the escalation phase; 42 subjects received 5e10vp. No dose-limiting toxicity or unexpected safety issues were identified by an independent review committee, and there were no treatment-related deaths. Adverse events were primarily consistent with underlying disease, effects of the neuro-procedure, expected effects of pembrolizumab, and concomitant use of steroids/anticonvulsants per the standard of care. The majority of events were mild to moderate, and unrelated to DNX-2401. Headache and manageable vasogenic edema were the most common events related to DNX-2401 with pembrolizumab. For the 48 subjects who received pembrolizumab (median 6 cycles), median OS from DNX-2401 administration was 12 months (95% CI, 10.6–14.7), OS6 was 91%, and 47% experienced clinical benefit (stable disease or better). Four subjects (5e10) had a partial response (two with > 94% regression of tumor), and three (5e8; 5e10[2]) are alive > 20 months. Updated safety and efficacy results will be presented. CONCLUSIONS The data continue to demonstrate that DNX-2401 administered with pembrolizumab has an acceptable safety profile. Long-term survival and clinical benefit remain compelling.
