It is difficult to summarize international trends in the incidence and mortality of ovarian cancer since they differ between countries and between age groups . Incidence rates are high in most of the industrial countries where women have relatively few children and lower in Asian and African countries with higher fertility rates. In recent years the mortality rate has started to decline in the younger age groups (under 55 years) but this is not reflected in the incidence data. Reproductive and hormonal factors are the main determinants of risk, with a decline in risk associated with increasing parity, oral contraceptive use, hysterectomy and sterilization by tubal ligation . Ovarian cancer differs from many other human tumors in displaying considerable disease heterogeneity, a poorly understood progression pathway, and a few good tumor markers. In addition, ovarian cancers are usually diagnosed at a later stage, and the survival rate, therefore, is poor .