Clinical trial challenges, design considerations, and outcome measures in rare CNS tumors

Identifying associations between sample characteristics, symptoms, and self-efficacy differences in adult patients with rare tumors of the central nervous system who participated in a novel web-based natural history study

OBJECTIVE

High self-efficacy is associated with improved self-care and reduced symptoms in cancer patients but has not been fully interrogated in adults with central nervous system (CNS) cancers. We aimed to identify the relationship between self-efficacy levels in managing emotions (SEMEM) and social interactions (SEMSI) by examining sample characteristics and symptom burden.

METHODS

Sample characteristics and patient-reported outcome (PRO) measures addressing self-efficacy (PROMIS SEMEM & SEMSI) and symptom burden (MDASI BT or SP) were collected in a novel web-based study of 158 adult patients diagnosed with rare CNS tumors.

RESULTS

The sample was predominantly female (73%), diagnosed with an ependymoma (66%), and had a median age of 45 (19-75). Low SEMEM was associated with a longer duration of symptoms before surgery (r = -0.26) and female gender (92%) among brain tumor (BT) participants and in spinal cord tumors (SCT), those with lower education (r = 0.29). Reporting low SEMSI was associated with being married (42%), lower education (r = 0.22), and a prolonged time with symptoms before surgery (r = 0.29) in those with BTs, with no associations identified in SCT. More severe mood-related interference (including mood, enjoyment of life, and relationship with others) was associated with lower SEMEM among both locations (r = -0.61 brain, r = -0.28 spine) and SEMSI in BT participants (r = -0.54).

CONCLUSIONS

Low self-efficacy was linked to a prolonged time between symptom onset and initial surgery, education, gender, and marital status and was associated with higher mood-related interference. Understanding characteristics associated with low self-efficacy underscores a need for future studies to tailor interventions that enhance self-efficacy.

From bench to bedside: Advancing towards therapeutic treatment of vestibular schwannomas

Vestibular schwannomas are rare intracranial tumors originating from Schwann cells of the vestibular nerve. Despite their benign nature, these tumors can exert significant mass effects and debilitating symptoms, including gradual hearing loss, vertigo, facial nerve dysfunction, and headaches. Current clinical management options encompass wait-and-scan, surgery, radiation therapy, and off-label medication. However, each approach exhibits its own challenges and harbors limitations that underscore the urgent need for therapeutic treatments. Over the past 2 decades, extensive elucidation of the molecular underpinnings of vestibular schwannomas has unraveled genetic anomalies, dysregulated signaling pathways, downstream of receptor tyrosine kinases, disrupted extracellular matrix, inflammatory tumor microenvironment, and altered cerebrospinal fluid composition as integral factors in driving the development and progression of the disease. Armed with this knowledge, novel therapeutic interventions tailored to the unique molecular characteristics of those conditions are actively being pursued. This review underscores the urgency of addressing the dearth of Food and Drug Administration-approved drugs for vestibular schwannoma, highlighting the key molecular discoveries and their potential translation into therapeutics. It provides an in-depth exploration of the evolving landscape of therapeutic development, which is currently advancing from bench to bedside. These ongoing efforts hold the promise of significantly transforming the lives of vestibular schwannoma patients in the future.

A critical analysis of neuro-oncology clinical trials

BACKGROUND

Limitations in trial design, accrual, and data reporting impact efficient and reliable drug evaluation in cancer clinical trials. These concerns have been recognized in neuro-oncology but have not been comprehensively evaluated. We conducted a semi-automated survey of adult interventional neuro-oncology trials, examining design, interventions, outcomes, and data availability trends.

METHODS

Trials were selected programmatically from ClinicalTrials.gov using primary malignant central nervous system tumor classification terms. Regression analyses assessed design and accrual trends; effect size analysis utilized survival rates among trials investigating survival.

RESULTS

Of 3038 reviewed trials, most trials reporting relevant information were nonblinded (92%), single group (65%), nonrandomized (51%), and studied glioblastomas (47%) or other gliomas. Basic design elements were reported by most trials, with reporting increasing over time (OR = 1.24, P < .00001). Trials assessing survival outcomes were estimated to assume large effect sizes of interventions when powering their designs. Forty-two percent of trials were completed; of these, 38% failed to meet their enrollment target, with worse accrual over time (R = -0.94, P < .00001) and for US versus non-US based trials (OR = 0.5, P < .00001). Twenty-eight percent of completed trials reported partial results, with greater reporting for US (34.6%) versus non-US based trials (9.3%, P < .00001). Efficacy signals were detected by 15%-23% of completed trials reporting survival outcomes.

CONCLUSION

Low randomization rates, underutilization of controls, and overestimation of effect size, particularly pronounced in early-phase trials, impede generalizability of results. Suboptimal designs may be driven by accrual challenges, underscoring the need for cooperative efforts and novel designs. The limited results reporting highlights the need to incentivize data reporting and harmonization.

Cell-of-Origin and Genetic, Epigenetic, and Microenvironmental Factors Contribute to the Intra-Tumoral Heterogeneity of Pediatric Intracranial Ependymoma

Intra-tumoral heterogeneity (ITH) is a complex multifaceted phenomenon that posits major challenges for the clinical management of cancer patients. Genetic, epigenetic, and microenvironmental factors are concurrent drivers of diversity among the distinct populations of cancer cells. ITH may also be installed by cancer stem cells (CSCs), that foster unidirectional hierarchy of cellular phenotypes or, alternatively, shift dynamically between distinct cellular states. Ependymoma (EPN), a molecularly heterogeneous group of tumors, shows a specific spatiotemporal distribution that suggests a link between ependymomagenesis and alterations of the biological processes involved in embryonic brain development. In children, EPN most often arises intra-cranially and is associated with an adverse outcome. Emerging evidence shows that EPN displays large intra-patient heterogeneity. In this review, after touching on EPN inter-tumoral heterogeneity, we focus on the sources of ITH in pediatric intra-cranial EPN in the framework of the CSC paradigm. We also examine how single-cell technology has shed new light on the complexity and developmental origins of EPN and the potential impact that this understanding may have on the therapeutic strategies against this deadly pediatric malignancy.