Inclusion of minorities and women in cancer clinical trials, a decade later: Have we improved?

Abstract

BACKGROUND: Inclusion of diverse groups of participants in cancer clinical trials is an important methodological and clinical issue. The quality of the science and generalizability of results depends on the inclusion of study participants who represent all populations among whom these treatment and prevention approaches will be used. METHODS: We conducted a systematic review using OVID as the primary source of reports included. Based on 304 peer-reviewed publications, diversity in the inclusion and reporting of study participants during a decade of cancer treatment and prevention trials (2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010) is summarized. Recommendations are made for improvements in the science and reporting of cancer clinical trials. RESULTS: Of the 277 treatment trials and 27 prevention trials included in this report, more than 80% of participants were white and 59.8% were male. In the recent decade, race and sex are rarely used as selection criteria unless the trial is focused on a sex-specific cancer. 1 Their results were not encouraging. We report an update of that study, focused on identifying changes in enrollment in cancer treatment and prevention clinical trials a decade later (2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010).It is understood that cancer treatment and preventive efforts are not generalizable to the entire treatable population. Historically, however, the majority of studies assessing the effectiveness of cancer treatment and prevention has been conducted using white men.1 An improved understanding of the differences between subgroups (race/ethnicity and sex) is critical to improving the risk/benefit profile for a wide range of chemotherapeutics and prevention efforts.Though much effort had been devoted to planning and implementation of programs aimed at reducing health disparities, the 2002 paper reported that minorities were still unlikely to be enrolled in clinical trials. There were 105 treatment trials that reported including both men and women, representing 42,355 participants; 38.6% of the participants were women. Results were fairly similar (34.7% of the participants were women) for the prevention studies. Age distribution and sex were reported in more than 90% of the trials (both treatment and prevention), yet race or ethnicity were reported in only 35.1% of the included treatment trials and 53.6% of the prevention trials. Within the 57 treatment trials (with 45,815 participants) which reported race or ethnicity, 10.5% of participants were reported as African American, and fewer than 1% were reported as Hispanic, Asian, or Native American. There was even less racial and ethnic diversity within the prevention trials: only 5.5% of participants were African American, 1.7% were Hispanic, and fewer than 1% were Asian or Native American.

Gender differences in clinical registration trials: is there a real problem?

“…cancer, vascular surgery and cardiovascular trials 9, 10, 11, 12, 13), with the general media continuing to report that large gender gaps are still putting women at a disadvantage 14. This reporting has had serious effects on policy, with large amounts of money being allocated to study gender differences in healthcare 15.…”

Adverse events in cancer patients with sickle cell trait or disease: case reports

“…3 Consequently, care providers likely would be unaware and subsequently might not associate nonspecific symptoms such as joint discomfort or declines in kidney function with a cause other than rigors of therapy. Lack of awareness of the range and impact of sickling-related events also might be a consequence of underrepresentation of minorities in clinical trials, 22 which has resulted in limited evidence about differing responses to cancer therapy by race and ethnicity. 1 Alternatively, it must be emphasized that the scarcity of evidence about serious complications simply might reflect a not unusual rate of adverse events among SCT or SCD patients with cancer.…”

Scientific and Ethical Considerations for Increasing Minority Participation in Clinical Trials

“…Not only are minorities under-represented in clinical trials, but the overall racial and ethnic composition of clinical trials is not reported at an acceptable rate. Between 1990 and 2000, only 35.1% of treatment studies among cancer clinical trials reported race/ethnicity [2]. This number increased to 51.6% from 2001 thru 2010, but the percentage of blacks included in the analysis for the second decade decreased by 42% [2].…”