For some small kidney cancers, freezing is more effective than heat treatment

For patients with early-stage renal cell carcinomas (RCCs) that measure between 3 and 4cm, cryoablation yields a lower risk of cancer-related death compared to thermal ablation, reports a preliminary study in the Journal of Urology

“In contrast, for patients with RCCs smaller than 3cm, either cold-based or heat-based therapy is just as effective in reducing cancer-specific mortality,” comments lead author Gabriele Sorce (San Raffaele Scientific Institute, Milan, Italy). “The findings may help us to better tailor the choice of ablation technique for patients with small RCCs.”

Lower risk of cancer death with cryoablation versus heating

Renal cell carcinoma is the most common type of kidney cancer. For patients with early-stage RCCs smaller than 4cm, an increasingly popular treatment option is destroying the cancer by freezing it or heating it. For these clinical stage T1a RCCs, ablation can provide high survival rates without the need for more extensive kidney surgery.

However, the outcomes of ablation appear “less favourable” for a subset of patients with clinical stage T1a RCCs: those whose tumours are between 3 and 4cm. Current European guidelines recommend cryoablation over thermal ablation for these cancers measuring 3 to 4cm, while US guidelines state that either treatment can be used. Both sets of guidelines state that freezing or heating can be used for T1a RCCs of 3cm or smaller.

To clarify the issue, an international research group analysed patients with stage T1a RCCs treated with freezing or heating between 2004 and 2018. Patients were drawn from the US National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) Program. The study focused on two matched groups of patients with cancers measuring between 3 and 4cm: 757 treated with cryoablation and 388 with thermal ablation.

Median age at treatment was 71 years. Follow-up data on cancer-specific mortality were available for 422 patients treated with freezing and 238 treated with heating.

Eight years after treatment, estimated cancerspecific mortality among patients with RCCs measuring 3 to 4cm was 8.5% for patients treated with cryoablation versus 12.9% for those undergoing heat-based thermal ablation. With both treatments, about 40% of patients died from causes other than cancer.

Implications for treatment decisions in ‘small, potentially curable’ kidney cancers

After adjustment for non-cancer-related death and other characteristics, patients undergoing thermal ablation for RCCs between 3 and 4cm were twice as likely to die of kidney cancer. In contrast, for patients with cancers smaller than 3cm, estimated cancerspecific mortality was similar between groups: 6.8% after cryoablation and 6.1% after thermal ablation.

The study is one of the first to directly compare clinical outcomes for freezing versus heating in patients with stage T1a RCCs measuring between 3 and 4cm. The results suggest that thermal ablation has “a highly statistically significant and clinically meaningful” disadvantage in terms of the long-term risk of death from kidney cancer, compared to cryoablation.

Otsuka Medical Devices and ReCor Medical submit premarket approval of Paradise ultrasound renal denervation system

Otsuka Medical Devices and ReCor Medical, a subsidiary of Otsuka, announce the filing of the premarket approval (PMA) application to the US Food and Drug Administration (FDA) for the Paradise ultrasound renal denervation (uRDN) system in the treatment of uncontrolled hypertension.

THE PARADISE URDN SYSTEM IS DESIGNED to reduce sympathetic nerve activity by denervating nerves surrounding the renal arteries to reduce blood pressure. It uses ultrasound energy to denervate the renal nerves and a water-filled balloon to protect the renal artery. The system employs an interventional procedure in which a catheter is placed in each of the main renal arteries, followed by delivery of two to three seven-second ultrasound emissions to denervate the surrounding renal nerves, thereby reducing blood pressure.

Since 2009, ReCor has been focused on developing and testing the Paradise uRDN system to treat hypertension safely and effectively. ReCor has three global, independently powered, shamcontrolled randomised clinical trials of the Paradise uRDN system in more than 500 patients with uncontrolled hypertension: RADIANCE-HTN SOLO, RADIANCE-HTN TRIO and RADIANCE II. Each trial met its prespecified primary efficacy endpoint of blood pressure reduction, with positive safety.

RADIANCE II is the US FDA’s investigational device exemption (IDE) pivotal trial. In September 2022, ReCor and Otsuka Medical Devices announced that the trial successfully reached its primary efficacy endpoint. Results showed a reduction in daytime systolic ambulatory blood pressure of -7.9mmHg in those treated with uRDN and a difference between uRDN and sham of -6.3mmHg (p <0.0001). The results from the all three RADIANCE clinical trials have been included in the submission for approval to the US FDA.

‘Bright future’ or ‘immense loss’?

Interventionalists split over shift towards ambulatory practice

A number of speakers took to the stage at the International Symposium on Endovascular Therapies (ISET; 16–19 January 2023, Miami Beach, USA) to debate the ‘ambulatory shift’ that is currently taking place in the interventional space.

AARON MAUCK (ADVISORY BOARD, Washington DC, USA), began with a keynote lecture describing the factors driving the migration of procedures away from the hospital towards ambulatory surgery centres (ASCs) and office-based labs (OBLs)—describing this as a “seismic shift” that “everyone is preparing for”. New reimbursement policies and regulations, provider competition and innovation are among major drivers of this trend. However, Mauck stated that “the future is not etched in stone” when it comes to the ambulatory shift, adding that industry investment and purchaser/referrer steerage are among factors that could accelerate this shift, while certain data indicating poorer outcomes with peripheral vascular procedures performed in the OBL—as well as US state legislatures not being amended—constitute barriers that may slow the process.

For ambulatory practices

Several key points extoling the virtues of more ambulatory, office-based practices were delivered by Jeffrey Carr (CardiaStream, Tyler, USA). Drawing on a 15-year experience of cardiac and vascular procedures in the ambulatory environment, Carr averred that greater control of their (his team’s) schedule and patients’ clinical care was among the initial motivations behind establishing an OBL in 2008, which was then transitioned to a hybrid lab—an OBLambulatory surgery centre (ASC)—in 2014. Here, the speaker cited the possibility for diversification and optimisation of revenue, a minimised impact on reimbursement cuts, and “higher standards” for existing OBLs as among the most important benefits.

After detailing the myriad peripheral vascular, cardiac and venous interventions that can currently be performed in his centre’s office-based settings—and touching on other future possibilities, such as aortic repairs and carotid stent placements— Carr concluded that it is “vital” to follow standardised processes/protocols, while also exercising transparency and reporting outcomes accurately. He further stated that “the future is bright” for expanding procedures, reducing costs and creating high value in office-based and ASC settings.