Introduction/Background*Breast cancer is uncommon in young women in developed countries. It is very heterogenous disease and studies showed, that young patients often have biologically complex and often more agressive tumours. However, little is known on markers available to improve assessment of prognosis or provide an additional therapeutic targets. One potential marker is the uPA-PAI-1 complex or each of the proteins individually. The protease uPA and its inhibitor PAI-1 have been implicated in cancer progression through facilitating tumour cell migration. The aim of this study was to evaluate the potential impact of uPA and PAI-1 as prognostic markers in young women with breast cancer.

Methodology We identified through the use of our institutional database on breast cancer 84 from 2283 (3.7%) of women diagnosed with breast cancer under the age of 45 years at the University Medical Centre Maribor, Slovenia between January 2009 – December 2019. An exam of clinical patient records was performed and clinico-pathological data were evaluated. Tumour tissue was prospectively analysed after primary surgical treatment and quantified using immunometric method ELISA sets. Values of uPA and PAI-1 were expressed in ng/mg of proteins. Correlations were evaluated using the Spearman rank test and continous data were compared using the Mann-Whitney U test. Data were evaluated using the SPSS for Mac version 23.0

Result(s)*Clinical data were available for 70 women with BC. Data on uPA/PAI-1 protein levels and the expression of the uPA-PAI-1 complex were available in 39 women (55.7%). The median age of patients in our study was 42.0 years (29-45). The complex of uPA/PAI-1 was significantly correlated with age at time of diagnosis (r_s=-.366, p<0.022). There was no significant correlation between the expression levels of uPA and levels of PAI-1 and oestrogen receptors, progesterone receptors, Ki-67 expression or tumour size. uPA/PAI-1 complex was also not significantly correlated with the hormone receptor negative (TNBC) breast cancer (p>.814).

Conclusion*Further research should evaluate the connection of age and the uPA/PAI-1 complex. uPA and PAI-1 did not show independant prognostic abilities in this pilot study.