Depth Dose Calculation of Holmium-166 for Different Shape Source by VARSKIN3 Code

Using beta emitter radionuclide is a useful therapeutic modality in the treatment of skin cancers in areas which are difficult to cure by other methods. The aim of this research is to evaluate the tissue response to beta rays of 166Ho and determine the feasibility of beta emitting radionuclide for treatment of skin cancers. In this work, we have calculated depth dose distribution of 166Ho using Varskin3 code. The code has been run for various input parameters to calculate absorbed depth dose for different shape of source. Absorbed depth dose variation has been calculated for166Ho beta emitter, in different shape of sources such as slab, spherical, cylindrical and 2-D disk shapes. Comparison of the result for different shape sources has been presented. The result shows that 2-D disk source induces damage to skin cells more than other shape of sources. These computational and Lee et al. experimental results are shown that 166Ho radionuclide treatment is very useful for skin cancer therapy. One of advantages of using 166Ho radionuclide is that no adverse effect on underlying bone and soft tissue due to the physical characteristics of beta rays, high linear energy transfer or rapid depth dose fall off is observed.