(S036) Increasing Representation of Randomized Controlled Trials Targeting Oligometastatic Disease

April 15, 2016

The number of new trials examining treatment of oligometastatic disease has risen since 2011, signifying a paradigm shift in the local treatment of oligometastatic disease. RT continues to be the primary intervention in RCTs evaluating oligometastatic disease.

Dustin Boothe, Meng Gan, BS, Shane Lloyd, MD; Huntsman Cancer Institute, School of Medicine, University of Utah

PURPOSE/OBJECTIVES: Studies demonstrate that aggressive local intervention among patients with oligometastatic disease can be associated with impressive rates of progression-free survival. We evaluated trends in current randomized controlled trials (RCTs) evaluating oligometastatic disease.

MATERIALS AND METHODS: Using the US National Institutes of Health database ClinicalTrials.gov, we conducted a search for RCTs consisting of cohorts with oligometastatic disease. For each identified trial, the following categories of data were collected: primary cancer, target site, intervention, phase, funding source, recruitment status, and trial start date. Joinpoint regression modeling was used to determine the rate and pattern of change of the introduction of new trials over time.

RESULTS: We identified 43 RCTs trials addressing oligometastatic cancer. The most frequently represented primary cancers were lung (27.9%), followed by prostate (20.9%) and breast (9.3%). Trials were most often site-nonspecific (79.0%). Radiation therapy (RT) was represented in at least one arm of 39 trials (90.7%), with stereotactic body RT (SBRT) being the most common mode of delivery (55.8%). In trials evaluating RT, targeted agents (18.6%) and chemotherapy drugs (20.9%) were the most common comparative modalities. Joinpoint analysis indicated that a model with one joinpoint (inflection in the model estimate over time) occurring in July 2011 fit the data better than a simple linear model (P = .007). This model showed no change in the rate of new trials before July 2011, with an average of two new trials per year. After July 2011, the annual rate of new trials introduced increased by 1.8 per year (P = .003). In 2014, the last year of the study, 13 new trials were introduced.

CONCLUSION: The number of new trials examining treatment of oligometastatic disease has risen since 2011, signifying a paradigm shift in the local treatment of oligometastatic disease. RT continues to be the primary intervention in RCTs evaluating oligometastatic disease.

Proceedings of the 98th Annual Meeting of the American Radium Society -americanradiumsociety.org