Hejazi P, et al. - Researchers performed a comparison of external beam radiation therapy (EBRT) with three-dimensional conformal radiation therapy (3DCRT), as a type of accelerated partial breast irradiation (APBI) technique considering the advantages of APBI to whole-brain radiation therapy and limitations for performing other techniques. They selected CT images of 24 patients with left-sided breast cancer after lumpectomy and categorized these patients into three groups based on the volume of breast, respectively, ≤ 1000 cc, 1000–1500 cc, and ≥ 1500 cc. As per results, UI in APBI method has more significant value than EBRT method. HI values between APBI and EBRT methods did not differ significantly. Findings suggest the possibility of the APBI method as a good method for reducing side effects and reducing treatment periods.