Growth in eligibility criteria content and failure to accrue among National Cancer Institute (NCI)-affiliated clinical trials.

BACKGROUND: Cancer trial accrual is a national priority, yet up to 20% of trials fail to accrue. Trial eligibility criteria growth may be associated with accrual failure. We sought to quantify eligibility criteria growth within National Cancer Institute (NCI)-affiliated trials and determine impact on accrual. METHODS: Utilizing the Aggregated Analysis of ClinicalTrials.gov, we analyzed phase II/III interventional NCI-affiliated trials initiated between 2008 and 2018. Eligibility criteria growth was assessed via number of unique content words within combined inclusion and exclusion criteria. Association between unique word count and accrual failure was evaluated with multivariable logistic regression, adjusting for known predictors of failure. Medical terms associated with accrual failure were identified via natural language processing and categorized. RESULTS: Of 1197 trials, 231 (19.3%) failed due to low accrual. Accrual failure rate increased with eligibility criteria growth, from 11.8% in the lowest decile (12-112 words) to 29.4% in the highest decile (445-750 words). Median eligibility criteria increased over time, from 214 (IQR [23, 282]) unique content words in 2008 to 417 (IQR [289, 514]) in 2018 (r2  = 0.73, P < 0.001). Eligibility criteria growth was independently associated with accrual failure (OR: 1.09 per decile, 95% CI [1.03-1.15], p = 0.004). Eighteen exclusion criteria categories were significantly associated with accrual failure, including renal, pulmonary, and diabetic, among others (Bonferroni-corrected p < 0.001). CONCLUSIONS: Eligibility criteria content growth is increasing dramatically among NCI-affiliated trials and is strongly associated with accrual failure. These findings support national initiatives to simplify eligibility criteria and suggest that further efforts are warranted to improve cancer trial accrual.

Patient-reported quality of life after stereotactic body radiation therapy versus moderate hypofractionation for clinically localized prostate cancer.

BACKGROUND AND PURPOSE: Evaluate changes in bowel, urinary and sexual patient-reported quality of life following treatment with moderately hypofractionated radiotherapy (<5Gray/fraction) or stereotactic body radiation therapy (SBRT;5-10Gray/fraction) for prostate cancer. MATERIALS AND METHODS: In a pooled multi-institutional analysis of men treated with moderate hypofractionation or SBRT, we compared minimally detectable difference in bowel, urinary and sexual quality of life at 1 and 2years using chi-squared analysis and logistic regression. RESULTS: 378 men received moderate hypofractionation compared to 534 men who received SBRT. After 1year, patients receiving moderate hypofractionation were more likely to experience worsening in bowel symptoms (39.5%) compared to SBRT (32.5%; p=.06), with a larger difference at 2years (37.4% versus 25.3%, p=.002). Similarly, patients receiving moderate fractionation had worsening urinary symptom score compared to patients who underwent SBRT at 1 and 2years (34.7% versus 23.1%, p<.001; and 32.8% versus 14.0%, p<.001). There was no difference in sexual symptom score at 1 or 2years. After adjusting for age and cancer characteristics, patients receiving SBRT were less likely to experience worsening urinary symptom scores at 2years (odds ratio: 0.24[95%CI: 0.07-0.79]). CONCLUSIONS: Patients who received SBRT or moderate hypofractionation have similar patient-reported change in bowel and sexual symptoms, although there was worse change in urinary symptoms for patients receiving moderate hypofractionation.