E-cadherin is a 120-kDa transmembrane glycoprotein involved in the calcium dependent adhesion of epithelial cells. Soluble E-cadherin fragment levels have been found to be significantly elevated in patients with different malignancies when compared to healthy controls (Katayama M. et al. Br. J. Cancer 69, 580-585, 1994). The aim of this paper was to assess the clinical relevance of preoperative serum E-cadherin assay in patients with ovarian carcinoma. E-cadherin was measured with a solid phase enzyme immunoassay based on a sandwich method using two mouse monoclonal anti-human E-cadherin antibodies. Preoperative serum E-cadherin levels were higher in 55 patients with ovarian carcinoma than in 31 patients with benign ovarian disease as controls, even though the difference did not reach the statistical significance (median value, range: 6615 ng/ml, 444-26,092 ng/ml versus 5531 ng/ml, 1548-12668 ng/ml, p = 0.063). However, the subset of the 36 patients with FIGO stage III-IV ovarian carcinoma had significantly higher antigen levels (median value, range: 7205 ng/ml, 444-26,092 ng/ml) when compared to controls (p = 0.039). Among patients with advanced ovarian carcinoma, preoperative serum E-cadherin correlated neither with the common clinico-pathological prognostic variables nor with the response to chemotherapy and survival. Our data seem to show that the preoperative serum E-cadherin assay does not offer useful clinical information for the management of patients with ovarian carcinoma.