Total Bone Uptake as a Quantitative Imaging Biomarker for Prostate Cancer With Bone Metastases

Area of Science:

• Nuclear medicine
• Oncology
• Medical imaging

Background:

• Conventional bone scintigraphy for prostate cancer bone metastases lacks reproducibility.
• Bone Scan Index (BSI) is semiquantitative and doesn't reflect uptake intensity.
• Quantitative SPECT/CT offers volumetric assessment of tracer uptake.

Purpose of the Study:

• To evaluate Total Bone Uptake (TBU) derived from GI-BONE as a quantitative biomarker for prostate cancer bone metastases.
• To assess TBU's utility in monitoring skeletal disease activity and treatment response longitudinally.
• To explore TBU as a complementary tool to conventional bone scintigraphy.

Main Methods:

• Retrospective review of three prostate cancer patients with bone metastases.
• Serial ^99mTc-HMDP bone SPECT/CT imaging between January and September 2025.
• Extraction of clinical data, PSA levels, and GI-BONE quantitative indices (BSI, metabolic bone volume, TBU).

Main Results:

• Serial TBU measurements objectively represented skeletal disease activity over time in all cases.
• Changes in TBU correlated with the clinical course and treatment response.
• TBU demonstrated potential for monitoring disease dynamics during follow-up.

Conclusions:

• GI-BONE-derived TBU is a practical quantitative biomarker for bone metastatic burden in prostate cancer.
• TBU provides objective and reproducible longitudinal information, complementing conventional bone scintigraphy.
• TBU aids in assessing treatment response and monitoring disease progression.