In a recent analysis by the RECIST Working Group published in the European Journal of Cancer, EORTC researchers had explored whether a more refined categorisation of tumour response or various aspects of progression could improve prediction of overall survival in the Response Evaluation Criteria in Solid Tumours (RECIST) database. They found that modelling target lesion tumour growth did not improve the prediction of overall survival above and beyond that of the other components of progression.
Progressive disease per RECIST 1.1 is defined as growth of measurable target lesions, presence of new lesions or unequivocal progression of non-target disease.
For their study, the EORTC team randomly selected data from 13 randomised clinical trials which included 3758 patients with breast, lung or colorectal cancer. A maximum of five target lesions contributed to the sum of longest diameters. At each measurement time they determined best target response as best percentage improvement from baseline, tumour growth of target lesions as worst percentage change and worst rate of increase from nadir, and presence of new lesions and occurrence of non-target progressive disease.
In current analysis, 36% of the patients had new lesions, 28% had non-target progressive disease, and 49% had experienced target lesion growth. The researchers found that no matter which type of tumour the patient had, next to initial response and measurable progression, the presence of new lesions and non-target progressive disease were independent factors linked with worse overall survival in a multivariate model.
Furthermore, the presence of new lesions, the occurrence of non-target progressive disease and initial response carried at least as much explanatory value for overall survival as progression based on measurable disease.
The authors concluded that modelling target lesion tumour growth did not show a marked improvement in overall survival prediction over and above the other components. These analyses enable a better understanding of the role of each component in progressive disease evaluation. Work is ongoing to incorporate this information into an updated version of RECIST with enhanced prediction of subsequent survival.
Dr Saskia Litière, EORTC biostatistician and lead author of the study said in an accompanying press release: "The World Health Organization criteria developed back in 1979, and more recently RECIST (Response Evaluation Criteria in Solid Tumors) in 2000 and then revised in 2009, have provided us with a unified set of tools for assessing tumour burden. These criteria allow standardised, comparable evaluation of tumour shrinkage in clinical trials, between patients, between trials, and across a wide range of tumor types. Analyses such as ours are indispensable in understanding the role of each component when evaluating progressive disease."
The RECIST Working Group includes EORTC, the United States National Cancer Institute, and the National Cancer Institute of Canada Clinical Trials Group.
This study was supported by the EORTC Charitable Trust. Clinical research data was made available to the RECIST data warehouse by Amgen, AstraZeneca, Breast Cancer International Research Group, Bristol-Myers Squibb, EORTC Breast Cancer and Gastrointestinal Tract Cancer Groups, Erasmus University Medical Center, Genentech, Pfizer, RadPharm, Roche, and Sanofi Aventis.
Litière S, de Vries E, Seymour L, et al. The components of progression as explanatory variables for overall survival in the Response Evaluation Criteria in Solid Tumours 1.1 database. Eur J Cancer 2014; Published Online April 10. DOI: 10.1016/j.ejca.2014.03.014.