Core Outcome Sets in Cancer Clinical Trials: Current Status and Future Opportunities

OBJECTIVES: Core outcome sets (COS) offer a solution to the problem of inconsistent, varied, and selective outcome reporting by standardising the outcomes that should be measured and reported in all trials in a specific area of health or health care. We aimed to review available cancer COS and assess their uptake in cancer clinical trials through surveying members of the European Organisation for Research and Treatment of Cancer (EORTC).

METHODS: The Core Outcome Measures in Effectiveness Trials (COMET) Initiative database was searched for cancer-specific COS on June 1st, 2023. Items on the use of COS in the cancer setting were included in a larger survey on outcomes distributed to EORTC members in November 2023 and closed in April 2024.

RESULTS: We identified a total of 87 cancer-related COS on the COMET database. Of these, 70 related to the tumour types as categorised by the EORTC and their disease orientated groups. A total of 710 (19%) EORTC members responded to the COS section of the survey of whom half (50%) stated they were unfamiliar with COS. Relevant COS were available to almost a quarter of respondents (23%), with a tenth utilising available COS. Amongst those who chose not to use an available COS, volume of outcomes, lack of time and failure to understand how to use COS were cited as key barriers.

CONCLUSIONS: Whilst COS are becoming increasingly available to, and acknowledged by, cancer clinical trialists, their implementation is currently still limited. The field of cancer could learn from rheumatoid arthritis (RA) where COS have been implemented since 1994 and were subsequently endorsed by the European Medicines Agency and the Food and Drug Administration in the late 1990s. The relevant RA COS are now reported in over 80% of RA trials, resulting in decreased selective outcome reporting, showing that improvement is possible.