Summary It is now clearly established that proteolytic enzymes, including plasminogen activator (uPA), play an important role in breaking down the extracellular matrix, which is considered to be a step in metastasis formation. Plasminogen activators are controlled at various levels. Two inhibitors, PAI-1 and PAI-2, have been identified, the latter being more specific for uPA. In attempts to determine their prognostic value, it is essential to investigate the relative importance of these parameters and their interactions. We used an immunoenzymatic method to assay uPA, PAI-I and PAI-2 antigens in cytosols prepared from 314 primary breast tumours. The patients were followed up for a minimum of 6 years and all relevant clinical and laboratory findings were recorded. Univariate analysis confirmed the poor outcome of patients whose tumours contained large amounts of uPA and PAI-1. In addition, low levels of PAI-2 correlated with shorter disease-free survival in the overall population (P= 0.02), post-menopausal women (P= 0.02) and women without lymph node involvement (P = 0.02). Multivariate analysis in the 'main effects' Cox model identified node involvement, macroscopic tumour size and PAI-2 as significant variables. The 'interactive' model, taking into account interactions between uPA and its two inhibitors, identified a first subgroup with a very poor prognosis associating either high levels of PAI-I with low levels of PAI-2 in the overall population and the women with no node involvement or high levels of uPA with low levels of PAI-2 in the group of menopausal women. We conclude that PAI-I provides the same prognostic information as uPA, and does not appear to play a role as an inhibitor. In contrast, PAI-2 increases the prognostic value of uPA, particularly in post-menopausal women, and PAI-1 in patients with no node involvement.

A dissemination risk index determined on primary tumor and taking into account the different effects of PAI-1 and PAI-2 on uPA can be of major help in clinical management of breast cancer, particularly in node-negative patients.

On univariate analysis, DFS and LCR were higher for DIP tumours. High SPF values were associated with shorter DFS. LCR, MFS, DFS, and OS rates were significantly different with an increasingly poorer prognosis from DL to AMH. On multivariate analysis, groups DL to AMH, histological node involvement and T stage were independently associated with MFS, and DFS. In N- patients, DL to AMH remained independent for MFS and DFS. For SBR III tumours, MFS and OS were significantly different in DL to AMH groups. These results strongly support the use of combined evaluation of DNA ploidy and SPF as independent parameters in clinical trials for N- stage I and II breast cancer.

Summary Urokinase-type plasminogen activator (uPA) is a potentially important prognostic factor in breast cancer for identifying patients at high risk of recurrence. This retrospective study assessed two enzyme-linked immunosorbent assay (ELISA) methods measuring uPA antigen levels in 499 primary breast cancer cytosols. Both uPA methods were applied to cytosols used routinely for oestrogen (ER) and progesterone (PgR) receptor assays. uPA was determined using a classical ELISA method (Imubind; American Diagnostica) and a novel automatic immunoluminometric assay (Lia; Sangtec Medical). The uPA Imubind method revealed about twice as much uPA antigen (median 0.75 ng mg-1 protein) as the uPA Lia method (median 0.38 ng mg-1 protein). The correlation coefficient between the two methods was acceptable (r = 0.81), but the two techniques are not interchangeable. Univariate analyses confirmed the poor outcome of patients whose tumours contained large amounts of uPA, regardless of the technique used. Multivariate analyses showed that uPA Imubind and uPA Lia values were both strong independent prognostic factors.Keywords: urokinase plasminogen activator; luminometric immunoassay; prognosis; breast cancer Evidence has accumulated that invasion and metastasis by solid tumours require the action of tumour-associated proteases, which promote the dissolution of the surrounding tumour matrix and basement membranes. In several independent studies of a variety of cancer types, i.e. breast (Dano et al, 1985;Duffy et al, 1988), colorectal (Ganesh et al, 1994;Skelly et al, 1995), lung (Oka et al, 1991), ovary (Kuhn et al, 1994), gastric (Nekarda et al, 1994;Cho et al, 1997) and bladder cancer (Hasui et al, 1992), high levels of the serine protease urokinase-type plasminogen activator (uPA) antigen in tumour extracts were associated with rapid disease progression and poor prognosis. In this study of 499 primary breast cancer tumours, we used two different assay methods for uPA antigen, in order to compare an enzyme-linked immunoassay (uPA Imubind; American Diagnostica) with a new automatic immunoluminometric assay (uPA Lia; Sangtec Medical), to assess the relationships between uPA values and clinical and histological factors and to evaluate the prognostic value of the two methods in multivariate analyses. MATERIALS AND METHODS PatientsThe study group consisted of 499 breast cancer patients treated at the Centre Rene Huguenin (CRH) between 1981 and 1989. The median age was 58 years (range 24-84 years). Patients were selected according to the following criteria: (1) primary, unilateral breast tumour; (2) full follow-up at CRH; (3) previously untreated, Correspondence to: C Bouchet without evidence of metastatic disease or any other malignant tumour at the time of diagnosis; (4) surgery as the first treatment; and (5) complete clinical, histological and biological information, especially concerning hormone receptors and antigen levels of uPA measured in cytosols by the two methods. All tumours were graded by a method based on the criteri...

Summary The concentrations of cathepsin D (Cath D), urokinase (uPA) and two plasminogen activator inhibitors (PAI-I and PAI-2) were analysed in the cytosols of 130 human mammary tumours (43 benign tumours and 87 primary and unilateral breast carcinomas). uPA, PAI-i and PAI-2 levels were measured by antigenic immunoassays and Cath D by immunoradiometric assay. The median levels of the four parameters were significantly higher in the malignant tumours than in the benign ones. Cath D and uPA increases were 4-fold and 5-fold respectively. PAI-I and PAI-2 increases were much more important, 74-fold and 29-fold respectively. In malignant tumours, median levels of Cath D and uPA did not vary according to classical prognostic factors (histologic grade, presence or absence of axillary lymph nodes, steroid receptors, UICC stage, tumour size, age, and menopausal status). However, PAI-I decreased in ER+ and PR+ tumours and PAI-2 increased in menopausal women's tumours. When Cath D, uPA, PAI-I and PAI-2 levels in malignant tumours were compared, positive correlations were found for all combinations. The implication of plasminogen activator inhibitors in the phenomenon was surprising and merits further investigation using tools other than global antigen measurements in tumours.