Nephrectomy Adds Benefit to Targeted Therapies in Metastatic RCC

Patients with metastatic renal cell carcinoma (mRCC) who undergo cytoreductive nephrectomy (CN) along with targeted systemic therapy have a survival advantage over those treated only with targeted therapies, according to a new study.

“The significant advent of targeted therapies has blurred the role of CN in contemporary patients diagnosed with mRCC,” wrote study authors led by Toni K. Choueiri, MD, of Dana-Farber Cancer Institute in Boston. Recent reports suggest that the use of CN has been declining, though guidelines still support it.

The study examined the utilization rates of CN in combination with targeted therapies in patients included in the National Cancer Data Base (NCDB). A total of 15,390 patients were treated with targeted therapies between 2006 and 2013; of those, 5,374 (35%) also underwent CN. The results of the analysis were published in the Journal of Clinical Oncology.

The utilization rate for CN remained stable across the period of the study, with an estimated annual percentage change of only +1.01% (P = .39). In terms of baseline characteristics, patients who underwent CN differed significantly with regard to age, comorbidities, and insurance status, among others, from patients who were treated only with targeted therapy.

On a multivariate regression analysis, a number of factors were significantly associated with the likelihood of undergoing CN. Each 10-year increase in age lowered the rate of CN substantially, and patients with a Charlson Comorbidity Index of at least 2 were less likely to undergo CN than those with a score of 0 (odds ratio [OR], 0.74; P < .001).

Black patients compared with white patients (OR, 0.64; P < .001), patients without insurance (OR, 0.76; P ≤ .025), and those treated at community and other hospitals compared with academic medical centers were also less likely to undergo CN. The authors noted that this last finding is particularly worrisome given that the NCDB represents only accredited centers who treat at least 100 cases annually, suggesting CN could be even more underutilized in the general population.

Overall, the mean time to death among those who underwent CN was 32.5 months, compared with 14.9 months for those who did not. After adjustment for a variety of covariates, patients who underwent CN had a lower risk of death than those who did not, with a hazard ratio of 0.49 (95% CI, 0.46–0.52; P < .001). Survival appeared better in patients who underwent CN after receiving targeted therapy compared with those who received treatment in the opposite order.

“To our knowledge, this study is the largest sample size to date showing that CN has an overall survival benefit in patients treated with targeted therapies, while adjusting for other factors,” the authors concluded. “However, careful patient selection remains critical in determining if patients will benefit from CN.”