Prostate-specific antigen is a new favorable prognostic indicator for women with breast cancer.
Prostate-specific antigen (PSA) is thought to be produced exclusively by prostatic epithelial cells and is currently used as a tumor marker of prostatic adenocarcinoma. We recently found that 30% of breast cancers contain PSA immunoreactivity (IR-PSA). To examine the prognostic value of PSA in female breast cancer, we measured IR-PSA in tumor cytosols of 174 breast cancer patients and classified the breast cancers as either PSA positive or PSA negative based on an IR-PSA cutoff level of 0.03 ng/mg. IR-PSA was present in 27% of the patients. IR-PSA presence was associated with early disease stage, small tumors, and estrogen receptor-positive tumors. We used the Cox proportional hazards regression model to analyze survival of patients in association with PSA status and found that patients with IR-PSA-positive tumors had a reduced risk for relapse and death in univariate analysis (P = 0.02 and 0.06, respectively) and a reduced risk for relapse in multivariate analysis (P = 0.03). Further analysis indicated that the effect of IR-PSA on relapse-free survival was evident in node-positive or estrogen receptor-negative patients. Our study suggests that IR-PSA is an independent favorable prognostic marker for breast cancer and may be used to identify a subgroup of estrogen receptor-negative and/or node-positive patients who have good prognoses.
Yu
H
H
Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada.
Giai
M
M
Diamandis
E P
EP
Katsaros
D
D
Sutherland
D J
DJ
Levesque
M A
MA
Roagna
R
R
Ponzone
R
R
Sismondi
P
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000737:chemistry* / Q000401:mortality / Q000473:pathology; D003600:Cytosol / Q000737:chemistry; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D017430:Prostate-Specific Antigen / Q000032:analysis*; D011960:Receptors, Estrogen / Q000032:analysis; D016019:Survival Analysis
D014408:Biomarkers, Tumor; D011960:Receptors, Estrogen; D017430:Prostate-Specific Antigen