Core outcome set (COS) for adolescents and young adults (AYAs) with cancer

Adolescents and young adults aged 15–39 years diagnosed with cancer are faced with unique challenges, which affect key developmental milestones and can create complex care needs. The aim of this study was to reach international consensus on the minimum set of outcomes to measure through the development of a core outcome set (COS). The COS development followed published methodological standards. A literature review and interviews with adolescents and young adults with cancer and health-care professionals generated a comprehensive list of 129 outcomes, spanning clinical and patient-reported outcomes relevant to adolescents and young adults with cancer. A three-round online Delphi survey involving three stakeholder groups globally, was implemented to reach international consensus. Overall, 262 respondents participated in the Delphi survey and 126 (48.1%) completed three survey rounds. 59 outcomes met consensus in round 3 and were taken forward to the consensus meeting. The final COS consists of 20 outcomes, including two on-treatment specific domains and three off-treatment specific domains. This study developed an adolescents and young adult-specific COS that, when implemented in clinical care and research, will improve the relevance of research findings, enhance care delivery, and enable consistent data synthesis across studies. Future efforts will focus on refining measurement methods and ensuring global applicability.

Aim

Adolescents and young adults (AYAs) with cancer, defined as individuals aged 15-39 years at initial cancer diagnosis, form a unique population; they face age-specific issues (e.g., fertility, employment, financial stability) as they transition to adulthood. AYAs report both negative (e.g. reduced quality of life) and positive (e.g. changes in outlook on life) impacts from cancer. Unlike dedicated healthcare and trials for pediatric and older adult cancer patients, AYA-specific healthcare services are scarce and vary across the world. Consensus on the main outcomes of importance to AYAs will catalyze the systematic collection and use of data to inform decision-making in research and cancer care. Thus, the field needs a core outcome set (COS), derived from a multi-stakeholder consensus-based process, that includes the minimum set of AYA-specific outcomes and associated high quality measures of those outcomes.
The methodological standards from the Core Outcome Measures in Effectiveness Trials (COMET) and the International Consortium for Health Outcomes Measurement (ICHOM) for COS development will guide the development of the COS for AYAs with cancer. The project will consist of the following phases: (1) define the scope of the COS; (2) establish the need for a COS in this field (3) assemble an international, multi-stakeholder working group; (4) develop a detailed protocol; (5) determine “what to measure” (i.e., outcomes); (6) determine “how to measure” (i.e., measures); and (7) determine “case-mix” variables (e.g. sex, ethnicity, type of treatment).
The development of a COS for AYAs with cancer will facilitate the implementation of efficient and relevant standards for data collection, both for clinical trials and in routine healthcare, thereby increasing the usefulness of these data to improve the value of the care given to these underserved young cancer patients.
The AYA-specific COS will define outcomes of interest alongside the tumor specific outcomes and therefor supplement tumor-specific COSs. In case of any overlap in outcomes, a reference to the correct tumor specific COS will be included, or in case no tumor specific COS is available yet, a notification stating that tumor specific outcomes need to be taken into account will be added.

Contributors

Anne-Sophie Darlington, Kirsty Way, Nicole Collaço, Charlotte Cairns, Simone Hanebaum, Silvie H M Janssen, Urška Košir, Martin G McCabe, Daniel Stark, Samantha C Sodergren, Winette T A van der Graaf, Olga Husson; STRONG AYA Consortium

Publication

Journal: The Lancet Oncology
Volume: 27
Issue: 1
Pages: -
Year: 2026
DOI: https://doi.org/10.1016/S1470-2045(25)00533-9

Further Study Information

Current Stage: Completed
Date: October 2022 - December 2025
Funding source(s): This research was funded by EU Horizon Europe program and UK Research and Innovation (UKRI), grant number 101057482 — STRONG-AYA — HORIZON-HLTH-2021-CARE-05.


Health Area

Disease Category: Cancer

Disease Name:

Target Population

Age Range: 15 - 39

Sex: Either

Nature of Intervention: Any

Stakeholders Involved

- Clinical experts
- Consumers (patients)
- Epidemiologists
- Methodologists
- Patient/ support group representatives
- Pharmaceutical industry representatives
- Policy makers
- Regulatory agency representatives
- Researchers
- Service commissioners
- Service providers
- Service users

Study Type

- COS for clinical trials or clinical research
- COS for practice

Method(s)

- Delphi process
- Interview
- Systematic review

The methodological standards from the Core Outcome Measures in Effectiveness Trials (COMET) and the International Consortium for Health Outcomes Measurement (ICHOM) for COS development will guide the development of the COS for AYAs with cancer. The project will consist of the following phases: (1) define the scope of the COS; (2) establish the need for a COS in this field (3) assemble an international, multi-stakeholder working group; (4) develop a detailed protocol; (5) determine “what to measure” (i.e., outcomes); (6) determine “how to measure” (i.e., measures); and (7) determine “case-mix” variables (e.g. sex, ethnicity, type of treatment).