High tumor tissue concentration of plasminogen activator inhibitor 2 (PAI-2) is an independent marker for shorter progression-free survival in patients with early stage endometrial cancer.

Previous studies including various tumor types have shown different associations between tumor tissue levels of plasminogen activator inhibitor 2 (PAI-2) and patient survival. High tumor tissue concentrations of PAI-2 have been associated with good prognosis in patients with breast cancer, small cell lung cancer and ovarian cancer, but with poor histologic differentiation and poor prognosis in patients with colorectal cancer. On the other hand, high tumor tissue concentrations of urokinase plasminogen activator (uPA), uPA receptor (R) and PAI-1 have more consistently been associated with poor histologic differentiation and poor prognosis. Our study quantified PAI-2 and uPAR using specific enzyme-linked immunosorbent assays in homogenates of 274 samples of endometrial cancer tissue. The prognostic power of each factor was analyzed in the subgroup of patients with early stage disease, i.e., International Federation of Gynecology and Oncology (FIGO) surgical stage I-II (n = 188). This group had a median follow-up time of 6.8 years (range 0.7-9.9), and 23 progressions were observed. The 80(th) percentile for PAI-2 and uPAR was used to dichotomize the material, and the results were analyzed for associations with clinical data including progression-free survival. The results were also compared with DNA ploidy status, S-phase fraction, uPA and PAI-1, which we reported in a previous study (Fredstorp Lidebring et al., Eur J Cancer 2001; in press). A high PAI-2 level was associated with shorter progression-free survival in univariate analysis and was an independent prognostic factor in bivariate analyses, which included PAI-1, uPA and DNA ploidy status. In contrast, a high level of uPAR had no association with prognosis in early stage endometrial cancer. The combination of high PAI-2 and PAI-1 levels in tumors revealed a small group of stage I-II patients with an accumulative progression rate of 50%.