In Silico Study on Electric Current Density in the Brain During Electrochemotherapy Treatment Planning of a Dog’s Head Osteosarcoma

Cancer is the most frequent cause of death in dogs. Osteosarcoma is a bone cancer common in dogs. Traditional treatments of osteosarcoma involve surgery and chemotherapy. Electrochemotherapy emerges as a possibility to treat the safety margin after a debulking, especially near vital organs like the brain. The use of electrochemotherapy near sensitive tissues to electric stimulation can be an issue. Preserving social aspects (recognition and temperament) is essential when treating a pet. Noxious brain stimulation is related to high electric current density (25 mA/cm²) and high electric charge density (5.24 C/cm²). This paper brings a series of in silico studies to evaluate the electric current density in a dog’s head osteosarcoma treatment in different bone destruction levels, with both needle and plate electrodes. The results show that all simulated cases induce electric currents in the brain. The worst-case scenario occurs when the plate electrode is directly in touch with soft tissues (all bone layers compromised by tumor infiltration), where the maximum electric current density was 3376 mA/cm². During our discussion, we adjust the transcranial direct current stimulation threshold to the electrochemotherapy exposure time, getting an electrochemotherapy threshold of 6.55 kA/cm². Even in the worst-case scenario, the calculated maximum electric current density is lower than the safety limit. We considered the application of electrochemotherapy safe near the brain, even with direct contact of the electrodes.