Despite a lot of research, the etiology and progression of breast cancer remain incompletely understood. Recently, human cytomegalovirus (HCMV) was reported as a risk factor for breast cancer. The aim of this study was to know whether breast cancer could be caused by cytomegalovirus or not? In this experiment seventeen samples of RAZI/A mice with spontaneous breast cancer were being gathered from laboratory animals department. Histopathology and polymerase chain reaction (PCR) tests were done on breast tissue samples. Formalin-fixed tissue specimens were obtained from mouse normal breast tissues (n:17) and mouse mammary tumors (n:17). Detection of mouse cytomegalovirus was done by the pUC57-MCK-2 plasmid. Our histopathology data showed Adenocarcinoma type B in mouse with mammary tumors. There was a significant difference between mice with spontaneous breast cancer and control by Pearson Chi-Square (Value: 17.000b and P=0.000). More research will be needed to determine the effect of cytomegalovirus on breast cancer.
