Photo Credit: Svitlana Hulko

The following is a summary of “Clinical Impact of the CARMENA Trial on Cytoreductive Nephrectomy Practices in the USA: A Difference-in-differences Analysis,” published in the September 2024 issue of Urology by Geduldig et al.

This study investigates whether cytoreductive nephrectomy (CN) practices in the United States have shifted following the publication of the Cancer du Rein Métastatique Nephrectomie et Antiangiogéniques (CARMENA) trial in 2018, which challenged the role of CN in metastatic renal cell carcinoma (RCC). The primary objective was to determine the effect of this pivotal trial on CN rates among patients with metastatic clear cell RCC (ccRCC). Using data from the National Cancer Database (2004–2020), a quasi-experimental difference-in-differences analysis was conducted to compare CN rates before and after 2018. The analysis also controlled for the localized nephrectomy (LN) rate in patients with nonmetastatic ccRCC, serving as the control group for assessing secular trends independent of metastatic disease status.

The results revealed a significant decline in CN rates post-CARMENA. Specifically, the difference-in-differences analysis identified a statistically significant decrease in CN rate, with a β-coefficient of –0.06 (standard error: 0.025, p = 0.028). This corresponds to an absolute reduction of 10.2% and a relative reduction of 31.8%, as the CN rate dropped from 34.7% to 21.9%, compared to the expected rate of 32.1%. These findings suggest a notable shift in clinical practice, likely influenced by the CARMENA trial’s publication, which questioned the utility of CN in the era of targeted therapies. However, the study also acknowledges that other unexamined factors, such as evolving systemic therapies or other contemporary clinical trials, may have contributed to this decline.

The study’s conclusions indicate that the CARMENA trial significantly impacted CN utilization in the United States, driving a marked reduction in the surgical management of metastatic RCC. Importantly, this shift occurred with minimal variation across regions, demographic groups, and healthcare facilities, suggesting a broad and consistent integration of the trial’s findings into clinical practice. These results underscore the trial’s influence on the evolving treatment paradigm for metastatic RCC and highlight the importance of evidence-based shifts in surgical decision-making.

Source: sciencedirect.com/science/article/abs/pii/S2405456924001743