Recently, photothermal therapy has gained wide popularity as an alternative treatment to conventional surgical techniques because it skips bleeding and renders rapid recovery after treatment than incisional surgery. 

Photothermal therapy causes tumor cell death by an increased temperature employing the photothermal effect, which changes light energy into thermal energy. 

A recent study performed a numerical analysis founded on heat transfer to generate apoptosis of tumor tissue under different heating circumstances in photothermal therapy. A multi-layered skin structure containing squamous cell carcinoma was evaluated using the Monte Carlo method. The numerical model was verified by tissue-equivalent phantom experiments. Founded on the effective apoptosis retention ratio, the numerical analysis results revealed the quantitative correlation for the laser intensity, volume fraction of gold nanorods injected into the tumor and cooling time. 

This research demonstrated optimal conditions for increased apoptosis within tumor tissue with minimum thermal damage to encircling tissues beneath various heating conditions. This technique can be used as a standard treatment while conducting photothermal therapy.

Source: Kim D, Kim H. Induction of apoptotic temperature in photothermal therapy under various heating conditions in multi-layered skin structure. Int J Mol Sci. 2021;22(20):11091.