Cancer Outcomes Tied to Your Genes

Chronic lymphocytic leukemia treatment response and survival times poorer in African Americans

(RxWiki News) As screening tests and treatments for cancer have improved, patients are living longer. However, some patients don't respond to treatment as well as others.

According to a recent study, African Americans with chronic lymphocytic leukemia (CLL) tended to have more severe forms of the cancer and survive fewer years than other patients.

Previously, researchers have suggested that this difference in outcomes for African Americans may be due to poor access to care. But the current study shows African Americans had similar access to treatment and care as other patients.

"Ask your physician about early diagnosis of cancer."

This study was conducted by Lorenzo Falchi, MD, and Alessandra Ferrajoli, MD, with colleagues from The University of Texas MD Anderson Cancer Center and the Duke University Medical Center in Durham.

Minorities often have a worse cancer prognosis (likely course of disease) compared to Caucasians, but it is unclear why. Frequent lower socioeconomic status and lack of access to good medical care have been proposed as possible reasons. But some studies have suggested that certain kinds of cancers can be more aggressive in minorities, which may explain their poorer outcomes.

For this study, the researchers looked at 84 African American patients and 1,571 non-African American patients with CLL who were referred to two cancer centers in Houston, TX and Durham, NC.

The patients were similar in a number of ways, including their access to health care. They also received the same treatments.

After looking at the data, the researchers found the time between diagnosis and referral to an oncologist (cancer specialist) was shorter for African Americans than Caucasians. This could have been incidental or because of more pronounced symptoms.

Further, African Americans were more likely to have more advanced CLL than Caucasians at the time of referral.

The researchers also found that although there was no significant difference in response to the first line of treatment or the level of care between African Americans and Caucasians, cancer in African Americans progressed faster and their survival rates were lower than Caucasians.

Overall, the results suggested that among patients with CLL, African Americans tended to have more advanced forms of the cancer and have shorter survival periods than Caucasians.

"These findings suggest that while inducing similarly high response rates, standard treatments do not overcome racial differences in outcome among patients with chronic lymphocytic leukemia," Dr. Ferrajoli noted in a press statement.

According to Dr. Ferrajoli, many questions are yet to be answered. For instance, is the difference in treatment response and survival rates related to differences in biologic characteristics or socioeconomic status?

Swaminathan Padmanabhan Iyer, MB, BS, MD, the leader of the Early Drug Development Program in Oncology and Hematology and co-director of the Malignant Hematology Program at Houston Methodist Hospital and dailyRx Contributing Expert said, "This is a good study but there are many questions that arise. Do all ethnic groups tolerate cancer treatment equally well and complete it? Do they have the social support to get them through the process? Or is there a specific gene in the African American community that makes the disease more severe, as is the case with triple negative breast cancer and myeloma?"

Dr. Iyer also noted, "One limitation of the study of course is that the number of subjects (84 patients) studied was very small."

Further studies in this area using more clinical data and specimens may be required to clarify these results, according to an editorial published along with the study.

The results of this study were published in July in Cancer, a journal published by the American Cancer Society.

No specific funding sources or conflicts of interest were disclosed.

Review Date: 
July 15, 2013