Expression of Epithelial Cell Adhesion Molecule in Paired Tumor Samples of Patients With Primary and Recurrent Serous Ovarian Cancer

Objective: Ovarian cancer (OC) recurrence constitutes a therapeutic dilemma with various novel targeted agents emerging that offer alternative treatment options. The aim of the present study was to evaluate and compare epithelial cell adhesion molecule (EpCAM) expression profiles in paired tumor samples of patients with OC relapse. Methods: EpCAM expression was analyzed by immunohistochemistry using the avidin-biotin- complex method on paraffin-embedded OC tissues obtained at primary surgery as well as on corresponding tumor samples of the same patients at relapse. The EpCAM overexpression was defined as 76% to 100% of tumor cells positively stained for EpCAM. Clinical data were collected within the Tumorbank Ovarian Cancer Network. Results: Nineteen patients with serous OC histology were included in the study (median age at primary diagnosis, 50 years; range, 40-74 years). The majority of the patients (95%) presented with International Federation of Gynecology and Obstetrics stage III/IV, and 68.4% of the tumors were poorly differentiated. A complete macroscopic tumor resection could be achieved in 15 patients (78.9%) at diagnosis. Epithelial cell adhesion molecule overexpression was detected in 17 (89%) of the primary and 16 (84%) of the recurrent tumors (P = 1.0); hence, no significant change of the EpCAM expression profile could be identified over time. Conclusions: Epithelial cell adhesion molecule expression profile appears to remain stable during the course from the primary throughout the relapse of serous OC. The results indicate that EpCAM might be an interesting therapeutic target structure in serous OC.