Disparities in Outcome: Causes and Dilemmas

Many studies have attempted to definitively explore the causes for disparities in stage at diagnosis and mortality across differing racial and socio-economic groups, both in California and elsewhere in the United States. Not surprisingly, researchers have often come to different conclusions about which possible causative factors are most important. A brief survey of the literature examines some of these factors.

It should be emphasized here that the problem of disparity in outcomes is far more racially and ethnically nuanced than the white-black focus that is the subject of most of the studies referenced in this report. Few studies have attempted to examine the many subpopulations within the larger categories of white, black, Hispanic and Asian.

A 2003 study of the SEER data between 1992–1999 looked at subgroups within the broad categories of Asians and Pacific Islanders, as well as in Hispanic whites.23 “Relative to non-Hispanic whites,” the study authors found, “blacks, American Indians, South and Central Americans, and Puerto Ricans had a 1.4- to 3.6-fold greater risks of presenting with Stage IV breast cancer.” A disproportionate number of blacks, Mexicans, and Puerto Ricans failed to receive appropriate surgery and radiation that met agreed-upon standards, the authors found. “In addition, blacks, American Indians, Hawaiians, Vietnamese, Mexicans, South and Central Americans, and Puerto Ricans had 20 percent to 200 percent greater risks of mortality after a breast cancer diagnosis.” Further, this study concludes that “for blacks, American Indians, Hawaiians, and Mexicans, these mortality differences persist even after adjusting for stage, ER status, PR status, and primary breast cancer treatments received.”