Trial Information

Incidence of Ovarian Cancer Ovarian cancer is the first mortality rate of gynecologic
malignancies (1-3) and became a more and more important disease in recent years (4-6). The
incidence of ovarian cancer also increased in recent year in Taiwan (7). Ovarian cancer has
the highest mortality of all gynecological cancers, with an overall 5-year survival rate of
only 20–30% (1). The lack of symptoms, difficulties in early diagnosis, insufficient
accurate tumor markers, and lack of information about ovarian tumor biology contribute to
the poor prognosis in ovarian cancer patients (8). The prognostic parameters for ovarian
carcinomas are tumor stage, histologic subtype, degree of malignancy, and residual tumor
after surgical treatment (9-12). However, these factors present an incomplete picture of the
tumor biology of ovarian cancer and are frequently interrelated (13). Thus, the
identification of new biologic factors predictive of individual disease course and prognosis
would be extremely useful. From the above-mentioned data, ovarian cancer indeed is a disease
that should be respected, however, there were only few of research work focusing on it in
Taiwan.

Tumor marker for ovarian cancer Detection of tumor markers that are released into the
circulation can aid in the diagnosis and/or monitoring of therapeutic responses of patients
with various tumors, including carcinomas of ovary (14-17), prostate (18), the
gastrointestinal tract (19, 20), or breast (21). CA125 is the most commonly used serum
marker for patients with ovarian carcinoma (14). Although it has proven clinically valuable
in monitoring the response of patients to therapy, some ovarian carcinomas do not express
CA125, and CA125 often is increased in patients with inflammatory disease. Thus, there is a
need for improvement, either in the form of a more specific and/or sensitive assay or an
assay that uses a different marker and can be used to complement CA125 toward the goal to
improve patient survival by improving diagnosis.

New potential molecule as tumor marker for ovarian cancer Mesothelin is a 40-kDa
glycosylphosphatidylinositol-linked glycoprotein. It is synthesized as a precursor of
molecular mass 69 kDa, which then is proteolytically processed into an N terminal secreted
form of molecular mass 30 kDa and a membrane-bound form of 40 kDa (22, 23). The 30-kDa
secreted form has been termed megakaryocyte potentiating factor (23). In normal tissues, the
expression of mesothelin has subsequently been shown to be largely restricted to mesothelial
cells, although immunoreactivity has also been reported in epithelial cells of the trachea,
tonsil, fallopian tube, and kidney (24). Mesothelin has been shown to be expressed in
pancreatic carcinomas(25), gastric carcinoma (26) and ovarian carcinoma (27), and it seems
that mesothelin may be utilized as a tumor marker for ovarian carcinoma.

We will evaluate the amount of mesothelin in pre- and post-treatment serum samples of
patients with epithelial ovarian cancer. We will also correlate the clinicopathologic items
and the prognosis of ovarian cancer patients and evaluate whether mesothelin can be a new
rumor marker for ovarian cancer patients.