Label-free high-throughput photoacoustic tomography of suspected circulating melanoma tumor cells in patients in vivo
Pengfei Hai, Yuan Qu, Yang Li, Liren Zhu, Leonid Shmuylovich, Lynn A. Cornelius, Lihong V. Wang
Abstract
SIGNIFICANCE: Detection and characterization of circulating tumor cells (CTCs), a key determinant of metastasis, are critical for determining risk of disease progression, understanding metastatic pathways, and facilitating early clinical intervention. AIM: We aim to demonstrate label-free imaging of suspected melanoma CTCs. APPROACH: We use a linear-array-based photoacoustic tomography system (LA-PAT) to detect melanoma CTCs, quantify their contrast-to-noise ratios (CNRs), and measure their flow velocities in most of the superficial veins in humans. RESULTS: With LA-PAT, we successfully imaged suspected melanoma CTCs in patients in vivo, with a CNR >9. CTCs were detected in 3 of 16 patients with stage III or IV melanoma. Among the three CTC-positive patients, two had disease progression; among the 13 CTC-negative patients, 4 showed disease progression. CONCLUSIONS: We suggest that LA-PAT can detect suspected melanoma CTCs in patients in vivo and has potential clinical applications for disease monitoring in melanoma.