Intraoperative Assessment and Photothermal Ablation of the Tumor Margins Using Gold Nanoparticles

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Oncology

Background:

• Surgical resection is a standard cancer treatment, but accurately identifying tumor margins during surgery remains a significant challenge.
• Residual tumor cells after resection can lead to recurrence and reduced patient survival.

Purpose of the Study:

• To develop and validate a generalized method using optimized gold nanoparticles for intraoperative tumor margin detection and photothermal ablation.
• To assess the clinical translatability of this nanoparticle-based approach.

Main Methods:

• Gold nanoparticles were optimized for detection via surface-enhanced Raman scattering (SERS) imaging and for photothermal ablation using a near-infrared laser.
• The method was tested in mice with orthotopic colon and ovarian tumors for intraoperative margin delineation.
• Post-surgical adjuvant photothermaltherapy (aPTT) was employed to ablate residual micro-tumors.
• Pharmacokinetics, biodistribution, Raman contrast, aPTT efficiency, and toxicity were evaluated.

Main Results:

• The nanoparticles enabled sensitive, high-resolution delineation of tumor margins in live mice.
• Post-surgical ablation of residual tumors using aPTT significantly prolonged survival and delayed tumor recurrence by 15 days.
• The nanoparticles demonstrated long blood circulation (≈24 h), high tumor accumulation (4.87 ± 1.73%ID g^-1), and no observed toxicity.

Conclusions:

• This nanoparticle-based approach offers a versatile and sensitive method for intraoperative tumor margin detection and targeted ablation of residual disease.
• The technique shows promise for improving surgical outcomes and reducing tumor recurrence across various solid tumors.
• The demonstrated clinical translatability, including favorable pharmacokinetics and safety profile, supports its potential application in oncologic surgery.