Advancements in PET Imaging for Aggressive Cancers

Researchers have developed a novel positron emission tomography (PET) tracer, [64Cu]Cu-NOTA-EV-F(ab´)2, which enables rapid visualization of nectin-4, a protein frequently overexpressed in triple-negative breast cancer (TNBC) and urothelial bladder carcinoma (UBC). This innovative approach allows for same-day immuno-PET imaging, significantly enhancing diagnostic protocols by providing high-contrast images within hours of tracer administration. The findings were published in the September 2025 issue of *The Journal of Nuclear Medicine*.

New PET Tracer Allows Same-Day Imaging of Triple-Negative Breast andNew PET tracer enables same-day imaging of triple-negative breast and urothelial cancers

Nectin-4 is a critical biomarker implicated in tumorigenic processes such as cell proliferation and metastasis. It is overexpressed in approximately 24% of newly diagnosed breast cancer cases and accounts for about 90% of bladder cancers, often diagnosed at advanced stages. The ability to visualize nectin-4 expression is essential for patient stratification and monitoring treatment efficacy, particularly in aggressive cancers like TNBC and UBC.

New PET Tracer Allows Same-Day Imaging of Triple-Negative Breast and

The research team, led by Weibo Cai, PhD, at the University of Wisconsin Madison, evaluated two PET tracers: [64Cu]Cu-NOTA-EV (full-length antibody) and [64Cu]Cu-NOTA-EV-F(ab´)2 (fragmented antibody). Initial in vitro studies confirmed the tracers' selective interaction with nectin-4-positive cells. In vivo studies using xenograft mouse models demonstrated that the fragmented antibody tracer exhibited rapid tumor accumulation, reaching peak signal intensity within four hours post-injection. This rapid uptake resulted in improved tumor-to-background contrast, crucial for accurate lesion delineation.

New PET Tracer Allows Same-Day Imaging of Triple-Negative Breast and

Pharmacokinetic analyses indicated that [64Cu]Cu-NOTA-EV-F(ab´)2 had faster blood clearance and reduced nonspecific tissue retention compared to its full-length counterpart. This profile not only facilitates same-day imaging but also minimizes radiation exposure to non-target organs, enhancing patient safety in nuclear medicine.

New PET tracer enables same-day imaging of triple-negative breast and urothelial cancers

The modular nature of the antibody fragment and the versatility of isotopic labeling suggest that this imaging platform could be adapted for various oncological targets and molecular signatures. The ability to perform rapid, noninvasive imaging aligns with ongoing efforts in precision medicine, potentially improving treatment outcomes for patients with aggressive cancers.

New PET Tracer Allows Same-Day Imaging of Triple-Negative Breast and

Lei Kang, MD, PhD, from Peking University First Hospital, emphasized the transformative potential of this research, stating, “This study demonstrates that [64Cu]Cu-NOTA-EV-F(ab´)2 exhibits rapid, specific, and sustained accumulation in tumor tissues in TNBC and UBC models.” He noted that this approach could expand to other cancers and targets, making molecular imaging faster and more patient-friendly.

New PET tracer enables same-day imaging of triple-negative breast and urothelial cancersNew PET Tracer Allows Same-Day Imaging of Triple-Negative Breast and

The development of [64Cu]Cu-NOTA-EV-F(ab´)2 represents a significant advancement in the noninvasive visualization of aggressive cancers. This innovative PET imaging technique promises to reduce diagnostic latency, tailor treatment strategies more effectively, and ultimately improve clinical outcomes for patients with challenging malignancies like TNBC and UBC. Future research may explore the integration of this imaging approach with theranostic strategies, enabling simultaneous diagnostic imaging and targeted therapy delivery.

New PET Tracer Allows Same-Day Imaging of Triple-Negative Breast and