PLAU and breast carcinoma: Such a time-dependent relation between cell biological factors and (relapse-free) survival in primary breast cancer has recently been observed for PMN-E (Foekens et al, 2003), as well as for clinical and other biological factors like uPA (Yoshimoto et al, 1993; Schmitt et al, 1997b; Hilsenbeck et al, 1998).