Advances in bioheat transfer models for hyperthermia: A comprehensive review and future directions

With the rapid increase in cancer cases over recent decades, extensive research has focused on developing effective treatments. Among these approaches, hyperthermia stands out as a promising therapeutic option due to its non-invasiveness, non-toxicity, and favorable safety profile. However, challenges remain regarding precise temperature control and optimal adjustment of in vivo parameters. Therefore, bioheat transfer models are necessary to accurately predict tissue and organ temperature distributions during treatment. This paper provides a systematic review of the evolution of bioheat transfer models, ranging from the classical Pennes model to fractional-order models. It details the fundamental assumptions, mathematical formulations, advantages, and limitations of each model within the context of bioheat transfer research. Furthermore, the effects of blood flow on heat dissipation and tissue homogeneity are examined. In this context, major bioheat transfer models, including the continuum model, vascular model, and porous media model, are critically evaluated, emphasizing their applicability. This review also proposes a scheme for selecting appropriate models for different biological tissues, providing a theoretical foundation and practical guidance for bioheat transfer calculations in living tissues. The integration of emerging technologies, such as artificial intelligent (AI) and advanced in vitro models, for example, engineered tissue equivalents, is highlighted as a future trend. These advancements could enhance modeling accuracy, with biomimetic living tissues serving as more reliable platforms for model validation.