Prognostic value of PS2 and cathepsin D in 710 human primary breast tumors: multivariate analysis.

PURPOSEEvaluation of the prognostic value of cytosolic PS2 (pS2 protein) and cathepsin D in a large series of breast cancer patients by multivariate analysis taking into account steroid receptors and conventional prognostic factors.PATIENTS AND METHODSPrognostic factors were analyzed in 710 primary breast cancers (median follow-up, 4 years). PS2 and cathepsin D were measured by radiometric immunoassays. Estrogen receptor (ER) and progesterone receptor (PgR) status were assessed by radioligand binding assays and multiple-point Scatchard analysis.RESULTSThe best cutoff point for PS2 to discriminate between positive (61% of the tumors) and negative was 2 ng/mg protein (univariate P value in 5-year relapse-free survival = .003). For cathepsin D, no sensible cutoff point could be chosen, since there was a continuous association between the level of cathepsin D and relapse rate (P = .001). In Cox multivariate analysis, relapse rate decreased with age of premenopausal/perimenopausal patients and with PS2 or ster...