Los Angeles -- A new end-to-end PET imaging approach for
osteosarcoma can rapidly and reliably distinguish tumor tissue from normal
tissue and accurately assess surgical margins in real time. The novel platform,
presented at the Society of Nuclear Medicine and Molecular Imaging 2026 Annual
Meeting, has the potential to fundamentally reshape surgical practice for
osteosarcoma by enabling precise tumor resection, significantly reducing the
risk of local recurrence, and preserving maximum limb function.
Osteosarcoma is among the most aggressive primary malignant
bone tumors in children and adolescents. The current standard of care consists
of chemotherapy combined with radical surgical resection. Achieving complete
tumor removal is the core objective of surgical treatment, as positive margins
increase the risk of local recurrence and adversely affect long-term survival.
"Despite continuous advances in surgical techniques, orthopedic surgeons still
face a major challenge: how to delineate tumor margins accurately during
surgery so as to ensure complete tumor removal while maximizing preservation of
limb function," said Bo Mei, PhD, of Peking University Cancer Hospital and
Institute in Beijing, China. "The development of an innovative technology
capable of rapidly and reliably distinguishing tumor tissue from normal tissue
and accurately assessing surgical margins in real time has become an urgent
clinical priority in osteosarcoma management."
High expression of the protein B7‑H3 is observed in
over 80 percent of osteosarcoma cases, making it an attractive target for both
imaging and therapy. In the study, researchers developed and synthesized the
first B7-H3-targeted radiotracer, 68Ga-B7H3-BCH. Preclinical studies were conducted
to assess its ability to detect lesions in cell lines and in mouse models.
After determining that 68Ga-B7H3-BCH's diagnostic
performance was significantly superior to that of clinically used tracers,
researchers then established a B7-H3-targeted dual-modality integrated imaging
platform. The platform combined two complementary imaging probes -- 68Ga-B7H3-BCH
and a near-infrared B7H3 fluorescent probe -- to form an imaging pipeline for preoperative
staging, real-time resection navigation, and postoperative margin verification.
PET/CT mouse studies were conducted to determine tracer uptake around margins and
near-infrared fluorescence imaging was utilized during surgical resection to
identify and validate margins. Histological comparisons were used to assess the
platform s accuracy.
68Ga-B7H3-BCH PET/CT non-invasively and quantitatively
mapped B7-H3 expression throughout the body, enabling precise staging of
osteosarcoma. The near-infrared B7H3 fluorescent probe enabled real-time,
high-resolution visualization of tumor margins, and a rapid pathological margin
verification technique integrated into the platform completed margin assessment
within 30 minutes.
"The development and clinical translation of this integrated
platform will facilitate a paradigm shift in osteosarcoma care, from empirical 'surgery
plus systemic chemotherapy' to individualized, precision, closed-loop diagnosis
and treatment carrying major clinical and scientific significance," said Mei.
While the platform remains investigational, an ongoing PET
imaging study has provided early feasibility evidence in patients. Further
prospective clinical validation, safety assessment, regulatory review, and
optimization of clinical workflows are needed before this platform can be used
in patients with osteosarcoma.