ASSESSMENT OF LASER DOSIMETRY PARAMETERS FOR EFFICIENT THERMAL ABLATION OF A SKIN TUMOR

Pulsed laser-induced thermal therapy (LITT) can be considered an alternative technique for skin tumor treatment thanks to its noninvasive nature. It exploits a laser incident radiation in the near-infrared (NIR) wavelengths to promote the tumor temperature rise and, consequently, induce the cancer apoptosis and coagulative necrosis. In this context, gold nanoparticles (GNPs) are often injected in the tumoral tissue as a contrast agent to avoid an excessive penetration of the laser beam that could irreversibly damage also the healthy tissue surrounding the tumor to be treated. However, an improper calibration of the incident radiation dosimetry parameters, i.e., laser intensity, frequency, and duty cycle, could results in an ineffective treatment or causes undesired side effects such as skin overheating and apoptosis of healty tissue. Therefore, in this work the calibration of the above-mentioned parameters for an effective pulsed LITT enhanced with GNPs diffusion is investigated. A realistic intra-tumor injection of GNPs, contrast agent diffusion, and the thermal effects on skin tumors by means of LITT were modeled by means of a numerical solver based on the foam-extend v.5.0 library. Special attention was devoted to the optimal incident radiation intensity and pulse timing that maximize the tumor irreversible damaged area and minimize undesired apoptosis in the surrounding tissue.