KIM-1, Blood-Based Biomarkers May Show Promise in Kidney Cancer

As part of a collaboration between CancerNetwork® and KidneyCAN, Michael B. Atkins, MD, spoke about novel biomarkers that may play a role in the detection and prognosis of kidney cancer.

Atkins, a medical oncologist and the deputy director of the Georgetown Lombardi Comprehensive Cancer Center, described how PD-L1 may not demonstrate utility in the kidney cancer field, as a limited number of tumors appear to express PD-L1 positivity. Beyond the standard of sarcomatoid histology, he stated that a potentially promising biomarker is KIM-1, which may predict the presence of residual disease following nephrectomy. Additionally, he highlighted circulating tumor DNA (ctDNA) and proteomic markers as potential blood-based signals of immunotherapy benefit.

KidneyCAN is a nonprofit organization with a mission to accelerate cures for kidney cancer through education, advocacy, and research funding. Learn more about KidneyCAN’s mission and work here.

Transcript:

PD-L1 has not been a clinically useful biomarker in kidney cancer compared with other cancers, not because it doesn’t enrich for patients who benefit from immune therapy, but because it’s expressed in too few tumors, so most of the responders end up being PD-L1 negative. It can’t be used to select patients for treatment, but it could be a component of a combined biomarker approach.

The clinically useful biomarker right now is sarcomatoid histology; we see a much higher response rate in patients with sarcomatoid histology than in patients without it. All those patients who have a high sarcomatoid component of their tumors probably should get a pure immunotherapy regimen. One promising biomarker that we’ve been working on is KIM-1, which is a marker of kidney injury. It’s elevated in kidney cancer, and when it’s elevated after nephrectomy, it predicts whether residual disease is present. When it’s elevated in the metastatic setting and goes down at 6 weeks, it predicts long-term benefit from immune therapy. That is being explored more, as well as other blood-based biomarkers such as ctDNA or proteomic markers. Then, we’re constantly looking at other things, such as PD-1 on Tregs or terminally exhausted CD8 T cells as potential predictors for who might need more powerful combination immunotherapy regimens.