There are disparities in the treatment and outcome between older black and white patients who have renal cell cancer, with blacks having significantly lower survival rates, according to a new study.
In recent years, 5-year survival rates for renal cell cancer have improved among whites, the authors explain in the Journal of Clinical Oncology, but there has been little change in survival rates among blacks
Blacks were much more likely than whites to have other illnesses, in addition to kidney cancer, the authors found.
Far fewer black patients (61 percent) than white patients (70 percent) underwent surgery to remove the kidney, the report indicates. Blacks were still less likely than whites to undergo surgery after adjustment for a number of factors.
Blacks survived a median of 2.5 years, while whites survived a median of 3.2 years, the investigators report, but this difference was eliminated when they adjusted for other illnesses present in blacks and treatment type.
Among blacks who had their kidney removed, the survival rates were worse compared with those for whites who had their kidney removed. In contrast, blacks who did not have kidney removal surgery had better survival rates than whites who did not have the surgery.
[Editors Note: “Disparities in Treatment and Outcome for Renal Cell Cancer Among Older Black and White Patients,” by Sonja I. Berndt, et al. is available for reading on line or downloading as a PDF file here. A subscription is required. The abstract appears below.]
From the Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health; Department of Urology, James Buchanan Brady Urological Institute, Johns Hopkins School of Medicine, Baltimore; and Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD
Address reprint requests to Sonja Berndt, PhD, Division of Cancer Epidemiology and Genetics, National Cancer Institute, 6120 Executive Blvd, EPS 8012, MSC 7240, Bethesda, MD 20892-7240; e-mail: [email protected]
Purpose: Black patients with renal cell cancer have shorter survival compared with their white counterparts, but the causes for this disparity are unclear. To elucidate reasons for this inequality, we examined differences in treatment and survival between black and white patients.
Patients and Methods: A retrospective cohort study was conducted using data from the linked Surveillance, Epidemiology and End Results (SEER) cancer registry and Medicare databases. Participants included 964 black and 10,482 white patients age 65 years who were enrolled into Medicare and diagnosed with renal cell cancer between 1986 and 1999. Information on surgical treatment was ascertained from both databases, whereas data regarding coexisting illness and survival was obtained from the Medicare database.
Results: The percentage of black patients receiving nephrectomy treatment was significantly lower compared with whites (61.2% v 70.4%; P < .0001). After adjustment for age, sex, median income, cancer stage, tumor size, and comorbidity index, blacks were less likely to undergo nephrectomy treatment compared with whites (risk ratio = 0.93; 95% CI, 0.90 to 0.96). Overall survival was worse for blacks than whites even after adjustment for demographic and cancer prognostic factors (hazard ratio [HR] = 1.16; 95% CI, 1.07 to 1.25); however, additional adjustment for comorbidity index and nephrectomy treatment reduced the disparity substantially (HR = 1.00; 95% CI, 0.93 to 1.09). Conclusion: This study indicates that the lower survival rate among blacks compared with whites with renal cell cancer can be explained largely by the increased number of comorbid health conditions and the lower rate of surgical treatment among black patients. Supported by the Arguild Foundation and the Intramural Research Program of the National Cancer Institute, National Institutes of Health. This study used the linked Surveillance, Epidemiology and End Results—Medicare database. The interpretation and reporting of these data are the sole responsibility of the authors. Authors’ disclosures of potential conflicts of interest and author contributions are found at the end of this article.