Adolescent and young adult neuro-oncology: a comprehensive review

Challenges and limitations of clinical trials in the adolescent and young adult CNS cancer population: A systematic review

Background

The adolescent and young adult (AYA) cancer population, aged 15-39, carries significant morbidity and mortality. Despite growing recognition of unique challenges with this age group, there has been little documentation of unmet needs in their care, trial participation, and quality of life, particularly in those with primary brain tumors.

Methods

A systematic literature review of 4 databases was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards. Studies included editorials, reviews, and practice guidelines on the challenges and limitations faced by the AYA population. Papers had to address CNS tumors.

Results

Sixty-eight studies met the inclusion criteria. The challenges and limitations in clinical trials in the AYA population were synthesized into 11 categories: molecular heterogeneity, tumor biology, diagnostic delay, access to care, physician factors, patient factors, primary brain tumor (PBT) factors, accrual, limited trials, long term follow up, and trial design. The published papers' recommendations were categorized based on the target of the recommendation: providers, coordination of care, organizations, accrual, and trial design. The AYA cancer population was found to suffer from unique challenges and barriers to care and the construction of trials.

Conclusions

The AYA CNS cancer population suffers from unique challenges and barriers to care and construction of trials that make it critical to acknowledge AYAs as a distinct patient population. In addition, AYAs with primary brain tumors are underrecognized and underreported in current literature. More studies in the AYA primary brain tumor patient population are needed to improve their care and participation in trials.

Molecular testing for adolescent and young adult central nervous system tumors: A Canadian guideline

The 2021 World Health Organization (WHO) classification of CNS tumors incorporates molecular signatures with histology and has highlighted differences across pediatric vs adult-type CNS tumors. However, adolescent and young adults (AYA; aged 15–39), can suffer from tumors across this spectrum and is a recognized orphan population that requires multidisciplinary, specialized care, and often through a transition phase. To advocate for a uniform testing strategy in AYAs, pediatric and adult specialists from neuro-oncology, radiation oncology, neuropathology, and neurosurgery helped develop this review and testing framework through the Canadian AYA Neuro-Oncology Consortium. We propose a comprehensive approach to molecular testing in this unique population, based on the recent tumor classification and within the clinical framework of the provincial health care systems in Canada.

Comorbidity Burden in a Cohort of Adolescent and Young Adult Patients Diagnosed with Central Nervous System Tumors and Sarcomas

Purpose: Adolescent and young adult (AYA) oncology patients experience unique biological, behavioral, and socioeconomic challenges, for which provision of care must be tailored. AYAs with central nervous system (CNS) tumors and sarcomas represent a vulnerable population with worse outcomes and potential for serious sequelae from intense multimodal therapy. Comorbidity burden impacts treatment tolerance, adherence, and efficacy, yet has been understudied among these high-risk AYA patients. Methods: Utilizing a validated AYA oncology comorbidity index, we (1) measured comorbid conditions present at diagnosis in AYA-aged patients with CNS tumors and sarcomas and (2) compared baseline comorbidity burden across ascending AYA age groups (15-19, 20-29, and 30-39 years) and with pediatric patients (10-14 years). Results: The cohort included 131 AYAs and 50 pediatric patients. Mean comorbidity score significantly differed between pediatric (0.8) and AYA (1.7) patients, and across ascending age subgroups (0.8 [10-14] < 1.2 [15-19] < 1.7 [20-29] < 2.5 [30-39]). AYAs were significantly more likely than pediatric patients to have ≥2 or ≥3 comorbidities (47% vs. 18%, 24% vs. 6%), with increasing prevalence across ascending age subgroups. Frequency of overweight/obese status, smoking/substance use, obstetric/gynecologic conditions, and cardiovascular comorbidities increased with age. In multivariate analyses adjusting for sex, tumor type, and race, age remained a significant predictor of comorbidity score. Conclusions: AYAs with CNS tumors or sarcomas have a high burden of baseline comorbidities, which increase with age at diagnosis, conferring susceptibility to treatment-related toxicity and mortality. Improving the prognosis for AYAs requires appropriate identification of pre-existing comorbidities and tailoring therapeutic and supportive care accordingly.

Adolescent and young adult brain tumors: current topics and review

The management of brain tumors developed in adolescents and young adults (AYAs) is challenging because of their histological heterogeneity and low incidence. The brain tumor and its treatment interventions can negatively affect neurological, neurocognitive, and endocrinological function, and dramatically affect the circumstances of AYA patients progressing to further education, employment, and marriage. Specific support is thus necessary to maintain the quality of life (QOL) of AYA brain tumor patients. AYA patients and survivors require active intervention and support for returning to school or work, progressing to further education, finding employment, and preserving fertility. Recent cancer genome profiling revealed that AYA gliomas include pediatric- and adult-type genetic alteration. Insights into the biology underlying the distribution of tumors in AYAs may influence the development of prospective trials. A more individualized view of brain tumors may influence stratification of patients' in future clinical studies as well as selection for molecular targeted therapy. Here I review strategies for achieving a better outcome to decrease late effects and improve QOL.

Adolescent and young adult glioma: systematic review of demographic, disease, and treatment influences on survival

BACKGROUND

Prognostic factors in adolescent and young adult (AYA) glioma are not well understood. Though clinical and molecular differences between pediatric and adult glioma have been characterized, their application to AYA populations is less clear. There is a major need to develop more robust evidence-based practices for managing AYA glioma patients.

METHODS

A systematic review using PRISMA methodology was conducted using multiple databases with the objective of identifying demographic, clinical, molecular and treatment factors influencing AYA glioma outcomes.

RESULTS

40 Studies met inclusion criteria. Overall survival was highly variable across studies depending on glioma grade, anatomic compartment and cohort characteristics. Thirty-five studies suffered from high risk of bias in at least one domain. Several studies included older adults within their cohorts; few captured purely AYA groups. Despite study heterogeneity, identified favorable prognosticators included younger age, higher functional status at diagnosis, low-grade pathology, oligodendroglioma histology and increased extent of surgical resection. Though isocitrate dehydrogenase (IDH) mutant status was associated with favorable prognosis, validity of this finding within AYA was compromised though may studies including older adults. The prognostic influence of chemotherapy and radiotherapy on overall survival varied across studies with conflicting evidence.

CONCLUSION

Existing literature is heterogenous, at high risk of bias, and rarely focused solely on AYA patients. Many included studies did not reflect updated pathological and molecular AYA glioma classification. The optimal role of chemotherapy, radiotherapy, and targeted agents cannot be determined from existing literature and should be the focus of future studies.