Breast cancer frequently occurs in the left breast among both women and men [R. Roychoudhuri, V. Putcha, H. Møller, Cancer and laterality: a study of the five major paired organs (UK), Cancer Causes Control 17 (2006) 655-662; M.T. Goodman, K.H. Tung, L.R. Wilkens, Comparative epidemiology of breast