**1. Introduction**

22 Cancer of the Uterine Endometrium – Advances and Controversies

Wu, H., Goel, V. Haluska, F.G. ( 2003). PTEN signaling pathways in melanoma. *Oncogene*,

Zhou, X.P., Kuismanen, S., Nystrom-Lathi, M.et al. (2002). Distinct PTEN mutational spectra

in hereditary non-polyposis colon cancer syndrome-related endometrial carcinomas compared to sporadic microsatellite unstable tumors. *Human Molecular* 

Vol. 22, pp.3113-3122

*Genetics*, Vol. 11, pp. 445-450

Endometrial cancer (EC) is the most common malignancy of the female genital tract. Overall, about 2% to 3% of women develop EC during their lifetime [Jemal et al., 2006]. EC is a malignancy that occurs primarily in postmenopausal women.

Based on clinical and pathological features, EC is classified into 2 types [Bokhman, 1983]. Type I EC, represents the majority of sporadic EC cases (70-80%), is usually well differentiated and endometrioid in histology. Type II EC, represents the minority of sporadic EC cases (10-20%), is poorly differentiated and usually papillary serous or clear cell in histology [Bokhman, 1983; Lax, 2004; Doll et al., 2008].

The Epidermal Growth Factor system (EGF system) is present in human organs and play important role in embryogenesis and postnatal development [Casalini et al., 2004; Uberall et al., 2008].

Dysregulation of the EGF signaling network is implicated in various disorders [Marmor et al., 2004; Uberall et al., 2008]. In cancer, the EGF system contributes in proliferation, transformation, angiogenesis, migration and invasion [Holbro et al., 2003].
