A method for determining whether to administer an aggressive treatment or non-aggressive treatment to a patient with primary breast cancer, said patient having primary tumor tissue, said method comprising: (a) measuring the level of uPA protein and the level of PAI-1 protein or mRNA encoding uPA and mRNA encoding PAI-1 in said primary tumor tissue or a sample of said primary tumor tissue of said patient; (b) classifying said patient as low risk if the level of uPA is lower than a uPA cut-off value of at least the 55th percentile and at most the 75th percentile of normalized uPA levels in a randomized population of breast cancer patients and the level of PAI-1 is lower than a PAI-1 cut-off value of at least the 61 st percentile and at most the 81 st percentile of normalized PAI-1 levels in a randomized population of breast cancer patients, or as high risk if either the level of uPA is higher than the uPA cut-off value or the level of PAI-1 is higher than the PAI-1 cut-off value; (c) selecting a treatment regime by predicting an expected benefit in a comparable population of breast cancer patients, wherein said comparable population is defined as a population that shares the clinical factors nodal status, number of nodes affected, tumor size, tumor grade, patient's age, hormone receptor status, and menopausal status, wherein: (c-i) if said patient is classified as low risk in step (b), selecting a non-aggressive treatment regiment if said non-aggressive treatment results in a higher expected benefit, including a higher demonstrated overall survival or a higher disease-free survival, than aggressive treatment in a comparable population of low risk breast cancer patients; and (c-ii) if said patient is classified as high risk in step (b), selecting an aggressive treatment regimen if said aggressive treatment results in a higher expected benefit, including a higher demonstrated overall survival or a higher disease-free survival, than non-aggressive treatment in a comparable population of high risk breast cancer patients. (a) measuring the level of uPA protein and the level of PAI-1 protein or mRNA encoding uPA and mRNA encoding PAI-1 in said primary tumor tissue or a sample of said primary tumor tissue of said patient; (b) classifying said patient as low risk if the level of uPA is lower than a uPA cut-off value of at least the 55th percentile and at most the 75th percentile of normalized uPA levels in a randomized population of breast cancer patients and the level of PAI-1 is lower than a PAI-1 cut-off value of at least the 61 st percentile and at most the 81 st percentile of normalized PAI-1 levels in a randomized population of breast cancer patients, or as high risk if either the level of uPA is higher than the uPA cut-off value or the level of PAI-1 is higher than the PAI-1 cut-off value; (c) selecting a treatment regime by predicting an expected benefit in a comparable population of breast cancer patients, wherein said comparable population is defined as a population that shares the clinical factors nodal status, number of nodes affected, tumor size, tumor grade, patient's age, hormone receptor status, and menopausal status, wherein: (c-i) if said patient is classified as low risk in step (b), selecting a non-aggressive treatment regiment if said non-aggressive treatment results in a higher expected benefit, including a higher demonstrated overall survival or a higher disease-free survival, than aggressive treatment in a comparable population of low risk breast cancer patients; and (c-ii) if said patient is classified as high risk in step (b), selecting an aggressive treatment regimen if said aggressive treatment results in a higher expected benefit, including a higher demonstrated overall survival or a higher disease-free survival, than non-aggressive treatment in a comparable population of high risk breast cancer patients. (c-i) if said patient is classified as low risk in step (b), selecting a non-aggressive treatment regiment if said non-aggressive treatment results in a higher expected benefit, including a higher demonstrated overall survival or a higher disease-free survival, than aggressive treatment in a comparable population of low risk breast cancer patients; and (c-ii) if said patient is classified as high risk in step (b), selecting an aggressive treatment regimen if said aggressive treatment results in a higher expected benefit, including a higher demonstrated overall survival or a higher disease-free survival, than non-aggressive treatment in a comparable population of high risk breast cancer patients.