Site of primary tumor has a prognostic role in operable breast cancer: The International Breast Cancer Study Group experience

M Colleoni, D Zahrieh, RD Gelber, SB Holmberg, JE Mattsson, CM Rudenstam, J Lindtner, D Erzen, R Snyder, J Collins, MF Fey, B Thurlimann, D Crivellari, E Murray, C Mendiola, O Pagani, M Castiglione-Gertsch, AS Coates, K Price, A Goldhirsch