Ultrasound scan of a kidney with glowing cancer cells.

A New Way to Monitor Kidney Cancer After Ablation: Is Ultrasound the Answer?

Jordan Keane in Health & Wellness December 2025 • 4 min read.

"Contrast-enhanced ultrasound (CEUS) offers a promising alternative to traditional methods for monitoring kidney cancer recurrence after ablation, reducing risks and costs. But is it ready for widespread use?"

Kidney cancer, or renal cell carcinoma (RCC), affects a significant number of people. While surgery is a standard treatment, percutaneous ablation is another accepted option. After ablation, it's crucial to monitor patients for any signs of the cancer returning. Traditionally, this involves regular CT or MRI scans using contrast agents.

However, these contrast agents aren't without risks. They can be harmful to the kidneys and, in some cases, lead to a condition called nephrogenic systemic fibrosis. This is where contrast-enhanced ultrasound (CEUS) comes in as a potentially safer alternative.

A recent study has explored how effective CEUS is for monitoring RCC recurrence after ablation. The study aimed to identify specific imaging patterns that could indicate whether the cancer has returned. This article breaks down the findings, explaining what they could mean for patients and the future of kidney cancer surveillance.

CEUS: A Safer Way to Watch for Cancer Recurrence

Ultrasound scan of a kidney with glowing cancer cells.

The study involved 53 patients who had previously undergone RCC ablation. They were monitored using both 2D and 3D CEUS. Three radiologists with different levels of CEUS experience reviewed the ultrasound images, looking for specific signs of cancer recurrence and noting how confident they were in their diagnoses.

Here's what the researchers were looking for and what they found:

Recurrence: If the cancer had returned, the entire ablation cavity would show enhancement during the CEUS, with the contrast agent appearing at the same time and intensity as in the healthy kidney tissue.
No Recurrence: If there was no recurrence, the ablation cavity would either show no enhancement at all or a delayed enhancement starting from the edges of the cavity.
Accuracy: CEUS was highly accurate in detecting recurrence, with a sensitivity of 100% among all the readers. Specificity, or the ability to correctly identify when cancer had not returned, ranged from 90% to 94%.
Reader Agreement: The radiologists largely agreed in their assessments, with agreement rates between 88% and 96%.
3D CEUS: Adding 3D CEUS didn't significantly improve the results and, in some cases, reduced the radiologists' confidence.

These findings suggest that CEUS is a reliable tool for detecting RCC recurrence. Importantly, the study noted that some patients with complete treatment responses developed delayed enhancement at the edge of the ablation cavity over time. This wasn't a sign of recurrence but rather indicated fat necrosis, scarring, or granulation tissue.

The Future of Kidney Cancer Monitoring: A Safer, More Accessible Option?

This study adds to the growing evidence that CEUS is a valuable tool for monitoring RCC recurrence after ablation. It offers a safer alternative to CT and MRI scans, especially for patients with kidney problems. The ability to accurately detect recurrence while avoiding potentially harmful contrast agents is a significant advantage.

While the study has some limitations, such as the relatively small number of recurrence cases, the results are promising. Further research with larger groups of patients is needed to confirm these findings and better define the role of CEUS in RCC surveillance.

If further studies continue to support CEUS as a safe and effective monitoring tool, it could become a standard practice, improving the quality of life for many kidney cancer patients.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1016/j.urology.2018.05.053, Alternate LINK

Title: Long Term Surveillance Of Renal Cell Carcinoma Recurrence Following Ablation Using 2D And 3D Contrast-Enhanced Ultrasound

Subject: Urology

Journal: Urology

Publisher: Elsevier BV

Authors: Brian P. Calio, Andrej Lyshchik, Jingzhi Li, Maria Stanczak, Collette M. Shaw, Robert Adamo, Ji-Bin Liu, Flemming Forsberg, Costas D. Lallas, Edouard J. Trabulsi, John R. Eisenbrey

Published: 2018-11-01

Everything You Need To Know

What is contrast-enhanced ultrasound (CEUS) and why is it being considered for kidney cancer monitoring?

Contrast-enhanced ultrasound, or CEUS, is a technique that uses ultrasound along with contrast agents to visualize tissues and organs. It is being explored as a safer way to monitor kidney cancer recurrence after ablation, avoiding the risks associated with traditional CT and MRI scans, which also use contrast agents that can be harmful to the kidneys and potentially cause nephrogenic systemic fibrosis. CEUS aims to provide accurate imaging while minimizing patient risk and cost.

How does contrast-enhanced ultrasound (CEUS) distinguish between cancer recurrence and the absence of cancer recurrence after kidney ablation?

In the context of renal cell carcinoma (RCC) monitoring after ablation, recurrence is indicated in CEUS when the entire ablation cavity shows enhancement during the CEUS procedure. This enhancement appears at the same time and intensity as in the healthy kidney tissue. Conversely, if there is no recurrence, the ablation cavity will either show no enhancement at all or a delayed enhancement starting from the edges of the cavity. The timing and extent of enhancement are crucial in differentiating between recurrence and other post-ablation changes.

How accurate is contrast-enhanced ultrasound (CEUS) in detecting renal cell carcinoma recurrence after ablation, according to the study?

The study demonstrated that CEUS has high accuracy in detecting renal cell carcinoma recurrence after ablation. The sensitivity of CEUS was found to be 100% among the radiologists involved, indicating its reliability in identifying recurrence when it is present. Specificity, the ability to correctly identify when cancer has not returned, ranged from 90% to 94%. These results suggest that CEUS is a highly effective tool for post-ablation monitoring, reducing the need for more invasive or risky procedures.

Does using 3D contrast-enhanced ultrasound (CEUS) improve the detection of kidney cancer recurrence after ablation?

While both 2D and 3D CEUS were used in the study, adding 3D CEUS did not significantly improve the detection of recurrence. In some instances, it even reduced the radiologists' confidence in their assessments. This suggests that the added complexity of 3D CEUS may not be necessary for accurate monitoring of RCC recurrence after ablation, and that simpler 2D CEUS may suffice.

What does it mean if there's delayed enhancement at the edge of the ablation cavity in contrast-enhanced ultrasound (CEUS) after kidney cancer ablation?

Delayed enhancement at the edge of the ablation cavity, observed in some patients after renal cell carcinoma ablation, does not necessarily indicate cancer recurrence. The study found that this delayed enhancement is often indicative of fat necrosis, scarring, or granulation tissue, which are common post-ablation changes. Differentiating between these benign changes and actual recurrence is critical to avoid unnecessary interventions and requires careful interpretation of CEUS images by experienced radiologists. Further research may explore methods to better distinguish these phenomena.