Background and Purpose:

Cancer is a major public health problem worldwide and is one of the most leading causes of death in the world. The number of cancer survivors is increasing because of early detection, new treatment methods and growth of the population. Also, the extensive researches continue to achieve the best practical treatment. Hyperthermia by High-Intensity Focused Ultrasound (HIFU) is one of the newest and the most practical non-invasive techniques in cancer treatment so, using HIFU in the treatment of solid cancerous tumors and its efficiency is evaluated in this paper.

Material and methods
In the method, the temperature is increased in the tissue and tumor by using HIFU absorption and maintains temperature. By maintaining temperature the condition is created so that Irreversible changes are occurred in the cells and it leads to cell death. So in this approach, heat is used to induce the tumor ablation without thermal damage to normal tissue surroundings. This technique can reduce significantly the side effects. It has the potential to cause selective necrosis by heating or cavitation without entering an electrode into the tumor. Also, using HIFU is considered to treat solid tumors, including prostate, liver, breast, kidney, bone and pancreas cancerous tumors. According the results, this approach could be an appropriate alternative technique to surgical excision. In addition, it relieves pain in the advanced cancer. Patients accept this method more easily, psychologically and cosmetically. Finally, HIFU ablation can induce immune response, and suppression of the tumor activity. Therefore, High-intensity focused ultrasound ablation may play a key role in future clinical cancer treatment.