Tetranectin positive expression in tumour tissue leads to longer survival in Danish women with ovarian cancer. Results from the ‘Malova’ ovarian cancer study

The primary objective of this study was to analyse Tetranectin (TN) expression in tumour tissues and TN serum concentration in 758 women with epithelial ovarian tumours. The second was to evaluate, whether TN tissue expression levels correlate with clinico‐pathological parameters and prognosis of the disease. Using tissue arrays we analysed the expression levels in tissues from 166 women with borderline ovarian tumours (BOTs) and 592 women with ovarian cancer (OC). A panel of three antibodies was used for immunohistochemistry: a polyclonal and two monoclonal antibodies. Serum TN was measured using the polyclonal antibody A‐371. Univariate survival analyses stratified for chemotherapy showed that positive tissue TN as demonstrated by the polyclonal antibody indicated a significantly longer overall survival (OS) (p = 0.0001) as well as cancer specific survival (CSS) (p < 0.0001). High serum TN was likewise found to imply longer OS (p < 0.0001) and CSS (p < 0.0001), whereas tissue staining with the two monoclonal antibodies failed to demonstrate any significant correlation with either survival type. Univariate Kaplan–Meier survival analysis performed on all OC cases showed a significantly longer OS (p = 0.0009) and CSS (p = 0.0006) for women with TN positive tumour tissue and in women with high serum TN levels (p < 0.0001 for both). However, in the multivariate Cox regression analysis, only serum TN was found to be an independent prognostic factor for OS (p = 0.01) and not for CSS (p = 0.08). In conclusion, our results predict that a positive TN expression of both tumour tissue and serum points to a more favourable outcome for OC patients.