Biological markers in pT1 and pT2 ovarian cancer with lymph node metastases

A relatively high incidence of pelvic and paraaortic lymph node metastases is found in patients with pT1 and pT2 ovarian cancer. This paper investigates the clinicomorphological parameters and the expression of various biological markers in these tumors in order to define possible risk factors for lymphatic dissemination.

In a retrospective study we identified 51 patients with pT1 and pT2 ovarian cancer. All patients underwent total hysterectomy, bilateral salpingo-oophorectomy, omentectomy, and systemic pelvic +/- paraaortal lymphadenectomy. The incidence of lymph node metastases in these patients and the clinicomorphological parameters of their tumors were examined. Immunohistochemistry was used to determine the expression levels of the cell proliferation marker Ki-67, the cell adhesion molecules CD44s and CD44v6, and the oncoprotein HER2/neu of the tumors and their respective lymph node metastases.

Lymph node involvement was found in 5 of 26 patients with pT1 ovarian cancer and in 6 of 25 patients with pT2 ovarian cancer. Serous adenocarcinoma was associated with a significantly higher incidence of lymph node metastases than other histological types (chi(2) = 4.7, P = 0.03). No correlation was found between tumor grade and the lymph node status. High Ki-67 expression was significantly correlated with spread to the lymph nodes (chi(2) = 4.2, P = 0.04), whereas expression of CD44s, CD44v6, and HER2/neu was not related to the lymph node status. Survival analyses showed no difference in disease-free and overall survival in patients with lymph node metastases compared to those without lymph node metastases. No association was seen among histological type, tumor grade, and immunohistochemically detected Ki-67, CD44s, CD44v6, and HER2/neu expression on the one hand and disease-free and overall survival on the other hand.

Our data suggest that in early stage ovarian cancer the serous histological type and tumors showing a high Ki-67 expression carry a high risk of lymph node metastases. With respect to prognosis our data showed a minor role for Ki-67, CD44s, CD44v6, and HER2/neu expression and the occurrence of lymph node metastases in pT1 and pT2 ovarian cancer.