An ideal cancer treatment method should not only cause primary tumor suppression but also induce an antitumor immunity, which is essential for control of metastatic tumors. A combination therapy using a laser, a laser-absorbing dye, and an immunoadjuvant guided by temperature measurement probes such as magnetic resonance imaging thermometry (MRT) and infrared thermography (IRT) can be an ideal treatment modality. Temperature distribution inside the target tissue is important in laser treatment. The surface temperature often serves as an indicator of the treatment effect. However, real-time monitoring of surface temperature during laser irradiation poses a great challenge. In this study, we investigated the surface temperature distribution using direct measurement and theoretical simulation. The preliminary results of in vitro and in vivo studies are presented. Gel phantom and chicken breast tissue were irradiated by an 805 nm laser and the surface temperature distribution was obtained using an infrared thermal camera. EMT-6 breast tumors in mice were treated using the 805 nm laser and with different dye and immunoadjuvant combinations, including intratumor injections of indocyanine green (ICG) and glycated chitosan (GC). Monte Carlo simulation for selective photothermal-tissue interaction was also performed for the surface temperature distributions. Our results demonstrated that the tissue temperature can be accurately monitored in real time and can be controlled by appropriate treatment parameters.

Date Published: 13 February 2007
PDF: 11 pages
Proc. SPIE 6438, Biophotonics and Immune Responses II, 64380D (13 February 2007); doi: 10.1117/12.698017

Published in SPIE Proceedings Vol. 6438:
Biophotonics and Immune Responses II
Wei R. Chen, Editor(s)