A population-based analysis of the rate of cytoreductive nephrectomy for metastatic renal cell carcinoma in the United States.

OBJECTIVE: To examine temporal, geographic, socioeconomic, and clinical determinants of cytoreductive nephrectomy (CNT) use in the surveillance, epidemiology, and end results (SEER) database, because CNT is known to improve survival in patients with metastatic renal cell carcinoma (mRCC).

METHODS: Within the SEER database, we identified 6226 mRCC patients, who were either treated with CNT (n = 2038) or underwent no surgery (n = 4188) between 1989 and 2004. Chi-square and chi(2) trend tests, as well as multivariate logistic regression models, were used to assess the effect of age, gender, race, region of residence, and year of surgery on the rate of CNT. Adjustment was made for the size of the primary tumor.

RESULTS: The overall rate of CNT was 30.5%. The rate of CNT increased in the most recent year quartile (P <.001), was more frequent in white patients (P = .005), males (P = .001), and younger patients (P <.001). Moreover, CNT was more frequently performed for larger primary tumors (P <.001). Finally, important variability was found to exist in the rate of CNT between the 9 SEER registries (range 29.5%-38.6%, P = .002). In multivariate logistic regression models, age (P <.001), race (P <.001), year of surgery (P <.001), primary tumor size (P <.001), and SEER region (P = .003) were independent predictors of CNT rate.

CONCLUSIONS: Racial and geographic variability in CNT rates is worrisome and warrants further attention. In view of the survival benefits of CNT, its access should be equal for all races and regions.