Size does matter, but it is certainly not the only way to monitor the efficacy of cancer treatment, according to Prof. Rodney Reznek, a professor of diagnostic imaging at St. Bartholomew's Hospital in London.
Imaging has served for half a century as a marker of therapy response, and size change is its most widely used measure. But the development of new drugs that are cytostatic rather than cytotoxic underscores that size may not be a reliable response assessment criterion any more. Functional imaging biomarkers should be considered as well, said Reznek during a special focus session at the 2009 ECR in Vienna.
A new version of the Response Evaluation Criteria for Solid Tumors, published recently in the European Journal of Cancer, reflects outlook changes. RECIST 1.1 set off a discussion regarding the need for new criteria and whether several advanced MRI and CT methods could be as useful as PET/CT in assessing therapy response.
