Exhibit Hall | Forum 9
Purpose: Basal cell carcinoma (BCC) is the most common human malignancy. The current standard of care involves visual discrimination of clinical treatment margins. However, this approach is prone to error due to limited intrinsic contrast between healthy/cancerous skin and yields incorrect initial tumor boundary assessments in 30-60% of cases. A novel optical polarization imaging (OPI) handheld device was developed to detect skin cancer by identifying tumor-induced disruption of the dermal collagen network.
Methods: In this IRB approved study, patients with biopsy confirmed BCC were imaged using a handheld OPI system prior to dermatologic surgery at University of Massachusetts Medical Center. Before imaging, the surgeon outlined clinical borders of the excision using a purple marker. Cross-polarized images acquired in vivo at 440 nm and 640 nm visualized dermal collagen structure and the surgical markings, respectively. Optical images were encoded using spectrally dependent properties of blood (oxyhemoglobin and deoxyhemoglobin) and melanin to reduce impact of background vasculature and pigmentation. Routine surgery then proceeded. Tumor margin evaluations from spectrally encoded OPI were compared to the surgeon’s visual estimate and validated against clinical histopathology.
Results: For this feasibility study, 9 subjects including 7 men and 2 women between 55-83 years old were imaged and analyzed. Image acquisition required < 1 second, whereas the entire imaging procedure required about 5 minutes per patient. Margin determinations obtained using the handheld imager demonstrated good correlation with histopathology. In 3 cases where the surgeon underestimated the lateral extent of tumor during preoperative examination, OPI successfully identified the entire tumor area.
Conclusion: The handheld OPI device facilitated rapid, in vivo collagen imaging and delineation of BCC margins. Future directions include further miniaturization of the technology and exploring applications to guide radiation therapy.
Funding Support, Disclosures, and Conflict of Interest: The project was funded by the Massachusetts Technology Transfer Center Acorn Innovation Fund and the Massachusetts Medical Device Development Center.
Optical Imaging, Polarized Light, Image Guidance