# Numerical Analysis of Human Cancer Therapy Using Microwave Ablation
## 4 Conclusions  
This paper has dealt with the numerical investigation of conductive and convective heat transfer associated with the propagation of electromagnetic waves in liver tissue during a microwave ablation process for different input microwave powers. The volumetric source term arose from the heat generated by the electromagnetic field since the liver is an electrically conductive material. A numerical simulation was performed using the finite element method to study the absorbed microwave power density, the temperature distribution profile and temporal evolution, the specific absorption rate, and the fraction of necrotic tissue within cancer cells. The results showed that SAR and temperature distribution are strongly affected by input microwave values. In other words, a higher microwave power induces higher SAR values and can increase the temperature to well above 50 \({}^{\circ}\)C, which will destroy healthy cells. The SAR pattern and the temperature profile exhibited elongated and asymmetric contour lines centered on the slot. The SAR and the temperature appeared very high near the antenna slot and then decreased by moving away from the antenna axis. The maximum of the SAR and temperature were reached inside the tumor region. The time required for complete necrosis was found to be 160 s, 60 s, and 40 s for 10 W, 45 W, and 75 W, respectively.  
In our work, the maximum temperature produced by microwave power \(P_{in}=10\) W was estimated to 86 \({}^{\circ}\)C, i.e., the rise temperature \(\Delta T=T-T_{b}=49\)\({}^{\circ}\)C. Furthermore, based on Figure 11, it was found that complete tumor necrosis had been reached only in the case of the position \(r=0.005\) mm away from the antenna, and the time required for complete necrosis was found to be 160 s for \(P_{in}=10\) W. This power is suitable for a small tumor size. The analysis of this study serves as an essential base for the microwave ablation process and can be used as a guideline for practical treatment. Nevertheless, more care must be taken and a certain compromise should be achieved to kill a maximal part of the tumor while conserving the healthy cells.  
Future work will be performed taking into account the size of the tumor with applied input microwave power using a programmable temperature-controlled system by incorporating a proportional-integral-derivative (PID) to better control the temperature distribution.  
[PERSON] proposed the idea, contributed to data acquisition, and performed the simulation. [PERSON] performed the algorithm construction. [PERSON] contributed to data analysis and the results discussion. All authors have read and agreed to the published version of the manuscript.  
Figure 11: Comparison of the four position fraction of necrotic tissue during the ablation thermal for three values of input microwave power, **(a)** 10 W, **(b)** 45 W and **(c)** 75 W.  
**Funding:** This research received no external funding.  
**Acknowledgments:** The authors would like to thank the Deanship of Scientific Research at Majmaah University for supporting this work under project number No. 38/138.  
**Conflicts of Interest:** The authors declare no competing financial interests.