African Americans with Chronic Lymphocytic Leukemia Do Not Live as Long as Caucasians, Despite Equal Care
A new analysis has found that among patients with chronic lymphocytic leukemia (CLL), African Americans more commonly present with advanced disease and tend to have shorter survival times than Caucasians despite receiving the same care. The results, published early online in Cancer, suggest that biologic factors may account for some racial disparities in cancer survival.
Among cancer patients, minorities tend to have a worse prognosis than Caucasians for reasons that are unclear. In African American patients, lower socioeconomic status and limited access to high-quality care often can play a role, but some researchers propose that certain cancers can behave more aggressively in minority individuals, which also can lead to worse outcomes.
Study Details
Because CLL is rare in African Americans, investigators from The University of Texas MD Anderson Cancer Center in Houston and the Duke University Medical Center in Durham, North Carolina, led a study that combined the two centers’ experiences with African American and Caucasian patients. Their analysis included 84 African American patients and 1,571 nonblack patients referred to the two centers. All patients, regardless of race, had access to health-care services and received the same treatments. “We sought to isolate race as a prognostic factor from other known demographic and clinical prognostic parameters in CLL,” explained study author Lorenzo Falchi, MD, of the Department of Leukemia at MD Anderson.
Outcomes
The investigators found that while the time from diagnosis (made either incidentally or because of clinical symptoms) to referral was shorter for African Americans than Caucasian patients (2.3 vs 4.1 months, respectively; P = .001), African Americans were more likely to have CLL that was more advanced at the time of referral. Patients in the nonblack group were more likely to have stage 0 disease than were African American patients (32% vs 21%, P = .02).
Although African Americans responded as well to first-line therapy as Caucasian patients, their cancer progressed more rapidly and their median survival was shorter. African American patients achieved overall response rates of 85% compared to 94% for Caucasian patients (P = .06), and complete response rates were 56% and 58%, respectively (P = .87). Event-free survival was 36 months for African American patients vs 61 months for Caucasian patients (P = .0007). The median overall survival was 152 months for African American patients and was not reached in the Caucasian arm (P = .0001, log-rank test). The inferior survival of African American patients persisted when patients were grouped according to factors related to the severity of their disease.
Questions Remain Unanswered
“These findings suggest that while inducing similarly high response rates, standard treatments do not overcome racial differences in outcome among patients with CLL,” said Alessandra Ferrajoli, MD, also of the Department of Leukemia at MD Anderson. She added that a number of questions remain unanswered. For example, do distinct biologic characteristics of African American patients with CLL account for the disparities seen in this study? And will these findings hold in the general population, where the impact of socioeconomic status may be more varied?
In an accompanying editorial, Christopher Flowers, MD, of Emory University in Atlanta, and Barbara Pro, MD, of Thomas Jefferson University in Philadelphia, noted that to adequately study disparities in leukemia, investigators will need to collect specimens and clinical data from patients to examine the potential impact of molecular and biologic markers. “Future studies in CLL can use this work as a cornerstone for investigating racial disparities in this disease,” they wrote.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
