Study objectives in clinical trials in older patients with solid malignancies: do we measure what matters?

Purpose: We set out to determine study objectives of clinical trials which included older patients with the four most common malignancies, to assess the extent to which the inclusion of patient-related outcomes (PROs) has changed over the last fifteen years. Method: A search of the National Institutes of Health clinical trial registry was performed to identify currently recruiting or completed phase II or III clinical trials started between 2005 and 2020, which addressed chemotherapy or immunotherapy in patients aged > 65 years with the four most common solid malignancies. Trial characteristics and study objectives were extracted from the registry website. Results: Compared to disease- and treatment-related outcomes, PROs were the least measured outcomes. Of the 1,663 trials, PROs were addressed in only 21% of all trials, in which quality of life as primary objective was found in less than 1% of all trials. Compared to all trials, trials exclusively for older patients addressed more often PROs (respectively, 30% vs 21%, p < 0.001). Over the last fifteen years, there was an incremental trend in the reporting of PROs from 17 to 24% of all trials (p = 0.007). Conclusion: Despite a slight incremental trend over the past 15 years, PROs appear to be underrepresented in clinical trials which include patients with a solid malignancy. In order to provide physicians and older patients with cancer realistic information about the impact of chemo- or immunotherapy on quality of life or functioning, researchers should strongly consider including PROs in their future clinical trials.