Mohammad Esmaeil Akbari - Cancer Research Centre (CRC), Shahid Beheshti University of Medical Sciences (SBUMS). Tehran I.R. Iran
Hamidreza Hamidreza - Cancer Research Centre (CRC), Shahid Beheshti University of Medical Sciences (SBUMS). Tehran I.R. Iran
Seyed rabi Mahdavi - Iran University of Medical Sciences, Tehran,I. R. Iran.
Nahid Nafisi - Iran University of Medical Sciences, Tehran,I. R. Iran

Breast cancer is the most common cause of malignant disease in women worldwide.During One decade local therapeutic strategies have changed from radical surgery, i.e.Mastectomy of The involved breast, to a multimodality treatment, consisting of breastconserving surgery, Followed by whole breast irradiation.Pathological analyses revealed that the greatest subclinical tumor cell density (90%) isconfined to an area of 4 cm surrounding the macroscopic tumor border. Therefore, thetumor bed itself represents a region with the highest probability of local tumor recurrences in a dimension of about 65-80% of all events