Purpose Histologic evaluation of prostatic needle biopsies is essential for prostate cancer (PCa) diagnosis and treatment planning, yet tissue targeting remains suboptimal despite MRI-guided Bx procedures. This pilot study investigates the use of label-free Fluorescence Lifetime Imaging (FLIm) for real-time biopsy guidance. Using ex vivo specimens, we assess FLIm’s preliminary efficacy in discriminating malignant from benign prostate tissue.

Materials and Methods Twenty patients undergoing prostate biopsy were enrolled. FLIm measurements were performed immediately after sample collection using a custom fiber-optic probe. Optical parameters from 4 spectral bands associated with distinct endogenous fluorophores including structural proteins and metabolic cofactors (e.g. NADH, FAD) were extracted and labeled based on histological annotation. Data were analyzed to characterize tissue-type differences and train and evaluate a classifier to distinguish malignancy.

Results Separation between benign tissue and Gleason grade ≥4 PCa was achieved using just 2 of 56 FLIm-derived parameters. A Support Vector Machine classifier using all parameters achieved a ROC of 0.88 in identifying grade 4 PCa. A reduced lifetime value in the NADH-associate band, likely due to increased free NADH from upregulated glycolysis, supports the biochemical basis for optical differentiation.

Conclusions FLIm shows significant potential for high-grade PCa identification. The single-fiber approach requires minimal modification for integration into current biopsy tools, supporting its feasibility for clinical translation.

Drs. Bec, Zhou, and Marcu are founders and equity holders of HiLight Surgical, Inc., a medical device company focused on the commercialization of fluorescence lifetime technology for clinical applications including prostate cancer diagnostics. Drs. Iczkowski and DallEra hold equity in HiLight Surgical. This relationship has been disclosed to University of California, Davis and managed in accordance with institutional conflict of interest policies. The remaining authors declare no competing interests related to this work.

National Institutes of Health (P41EB-032840). The authors wish to acknowledge the support of the UC Davis Comprehensive Cancer Center Biostatistics Shared Resource, supported by the National Cancer Institute of the National Institutes of Health under award number NCI P30CA093373.

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IRB of University of California, Davis gave ethical approval for this work

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Funding/Support: National Institutes of Health (P41EB-032840).

Conflict of Interest Disclosures: Drs. Bec, Zhou, and Marcu are founders and equity holders of HiLight Surgical, Inc., a medical device company focused on the commercialization of fluorescence lifetime technology for clinical applications including prostate cancer diagnostics. Drs. Iczkowski and Dall’Era hold equity in HiLight Surgical. This relationship has been disclosed to University of California, Davis and managed in accordance with institutional conflict of interest policies. The remaining authors declare no competing interests related to this work.

Ethics Statement: Institutional Review Board, Ethics Committee or Ethical Review Board study approval; all human subjects provided written informed consent with guarantees of confidentiality.

All data produced in the present study are available upon reasonable request to the authors