Finding and building consensus in kidney cancer trials

In this second part of our blog series on the work of the International Neoadjuvant Kidney Cancer Consortium (INKCC) we consider how the group has found and built consensus, and how to proceed through persistent convergence of opinion.

In 2024 and 2025, Dr Sabrina Rossi, Professor Grant Stewart and Professor Axel Bex conducted a Delphi exercise to assess the views of key opinion leaders in kidney cancer, the outcomes of which are published in the journal Annals of Oncology.

A Delphi exercise seeks to refine opinion among experts through rounds of questionnaires, feedback and discussion. To this end, INKCC canvassed experts in an online survey (1st round n=28), then held two in-person meetings (Boston n=35, Amsterdam n=18) at which survey results were shared, and experts had space to review and revise their opinions, this was followed by a second round of online survey (n=36).

After this process, Dr Rossi identified 15 statements on which there was consensus (defined as concordance between ≥70% of respondents). Key findings included:

• A clear strategy is urgently needed to assess neoadjuvant therapies in kidney cancer (96%), and an international consortium is necessary to address this (83%)

• The optimal length of neoadjuvant therapy is uncertain (87%)

• There are too many single-centre, single-arm neoadjuvant phase II trials with different drugs, combinations, length of treatment, endpoints and eligibility criteria (82%)

• Multi-arm adaptive platform trials are needed (87%).

The INKCC’s priorities have been informed as much by areas of disagreement as by the areas where there is consensus. For the areas where consensus has not yet been reached, the consortium is getting to work on research into the topics where there was a lack of consensus with the aim of moving towards agreement.

In some areas, opinion shifted towards consensus through the Delphi exercise. For example, in opinion on the usefulness of pathological response as an efficacy marker. Between the two surveys, the proportion of respondents agreeing with the statements in this area moved from 50% and 56.5% to 62.5% and 65.6%. Based on this finding, INKCC members Dr James Jones and Dr James Blackmur led a consensus paper, due for publication in Lancet Oncology, proposing a unified definition of pathological response for use in neoadjuvant trials in kidney cancer.

This collaborative approach, involving researchers across the globe, is already defining best practices and protocols that will be shared and implemented across different settings, to ensure standards in neoadjuvant trial design and, as a result, comparability across kidney cancer research.

Read the full article here: ‘What is required to deliver practice-changing neoadjuvant trials in kidney cancer? An International Neoadjuvant Kidney Cancer Consortium Delphi study’, Annals of Oncology Volume, Available online 4 June 2025. (https://doi.org/10.1016/j.annonc.2025.05.540)