Revised guidelines should ease clinical trial workload

In collaboration with the Press Association

The first formal revision of the guidelines used by clinicians to measure the size of tumours and their response to treatment has been published - a move which should help to ease the workloads in clinical trials involving potential new cancer treatments.

Cancer Research UK welcomed the new guidelines.

RECIST (Response Evaluation Criteria in Solid Tumours) guidelines were first published in 2000 and are used in phase II and III clinical trials to measure a treatment's efficacy.

- Sarah Woolnough, manager of policy, Cancer Research UK

However, a number of questions and issues have arisen since then as a result of changing methodologies and available treatments and the new RECIST 1.1 guidelines - which appear in the European Journal of Cancer - address these.

Professor Jaap Verweij, a researcher at the Erasmus University Medical Centre in The Netherlands and clinical oncology editor of the journal, said that the updated criteria would affect all researchers running clinical cancer trials.

"RECIST 1.1 describes a standard approach to solid tumour measurement and definitions for objective assessment of change in tumour size for use in adult clinical trials," he explained.

Co-editor Professor Elizabeth Eisenhauer, from the National Cancer Institute of Cancer in Ontario, Canada, said that the revised guidelines should improve the consistency and standardisation of clinical trials.

"Drug development and clinical cancer research is a global enterprise. The more consistent we are in describing what we have seen and in using the same measures and endpoints, the more reliably we are able to interpret the results from a variety of sources," she observed.

The changed guidelines include a reduction in the number of tumours to be assessed from ten to five, and to a maximum of two tumours per organ - a move that Professor Eisenhauer said should have a "big implication for the workload in clinical trials...without any loss of information".

They also contain new guidance on measuring lymph node involvement; and the removal of the need to confirm response for randomised trials, in which the control arm can be used to interpret results.

In addition, the definition of disease progression has been refined to include a 5mm absolute increase in the size of the lesion, as well as a 20 per cent increase in size; and the revised criteria also contain guidance on imaging for the detection of new lesions and the interpretation of FDG-PET scan assessment.

Sarah Woolnough, Cancer Research UK's manager of policy, said: "We welcome the revision of these guidelines, which we hope will ease the burden on doctors running clinical trials and help them take new therapies through to patients more quickly."

The study authors hope that future revisions will incorporate the use of modern functional imaging techniques to assess treatments, but they explained that their use still awaits validation in large clinical trials.

Professor Eisenhauer emphasised that the new recommendations are "grounded in the literature and, where such information didn't exist - as was the case in some areas - we set about generating the evidence to guide and support the changes".

Ref: European Journal of Cancer, Volume 45, Issue 2, January 2009, Pages 228-247.

Response assessment in solid tumours (RECIST): Version 1.1 and supporting papers