Purpose: Enhancing minority retention to cancer trials is a primary focus of the NSABP Diversity and Strategic Planning Working Group (DSPWG). The DSPWG reviewed retention data for minorities enrolled on NSABP's recent cancer treatment trials to determine whether minority and non-minority patients were retained in equal proportion.

Methods: The DSPWG examined NSABP protocols B-30 to B-36, B-38, B-39, C-08, and R-04 opened to accrual between 1999 and 2007. As of October 29, 2007, the date of data accession, B-35 and B-38 were closed to accrual, B-36, B-39, and R-04 were still open to accrual, and B-30 to B-34 were in follow-up phase only. Patients were considered retained if they had not withdrawn consent or been designated “lost to follow-up” as of that date. Because of changes in federal guidelines for the self-reporting of race and ethnicity, retention data are presented separately for protocols B-30 to B-34 and B-36, B-38, B-39, C-08, and R-04.

Results: Race, ethnicity (Hispanic vs non-Hispanic), and retention data were available for 33,575 patients enrolled in these trials. Of the 17,974 patients in trials B-30 to B-34, the retention rate was 97.1% (14,992 / 15,441) among patients who reported their race as “White (not Hispanic)”. The corresponding rates for “Hispanic” and “Black (not Hispanic)” patients were 95.4% (606 / 635) and 95.1% (1214 / 1276), respectively. Patients in other racial categories were retained at a rate of 95.3% (593 / 622). Among 15,601 patients in trials B-36, B-38, B-39, C-08, and R-04, patients who reported their races as “White” and “Black or African American” were retained at rates of 98.3% (13,374 / 13,603) and 98.6% (1235 / 1252), respectively. 98.0% (731 / 746) of patients in other racial categories were retained. Patients who reported their ethnicities as “Hispanic” and “Non-Hispanic” were retained at a rate of 98.4% (773/786 and 13,618/13,840, respectively). 97.3% (949/975) of patients with unknown ethnicity were retained.

Conclusions: NSABP treatment trial retention rates are historically high. In the trials we examined, these high rates apply to minorities as well as to non-Hispanic whites. The perception that minorities are not retained in long-term clinical studies may be a faulty one and should be reconsidered in light of these results. Because greater participation in clinical research by minorities may help lessen disparities in health care, it is critical that researchers strive to enroll more of these patients into clinical trials.

Second AACR International Conference on the Science of Cancer Health Disparities— Feb 3–6, 2009; Carefree, AZ