Endometrial carcinoma (EC) is the most common malignancy of the female genital tract in developed countries. According to its histomorphologic characteristics EC is divided into endometroid and serous carcinoma; among less common subtypes there are clear cell, mucinous, neuroendocrine and undifferentiated carcinoma and carcinosarcoma. Endometroid and serous EC were essential for the so-called dual classification of EC (type I and type II), which considered mainly epidemiological, clinical and endocrine characteristics. It was shown that part of the high-grade serous carcinomas (type II) can develop from the endometroid EC by a multiplication of genomic changes and there are also EC, in which both basic types are overlapping. Today it is known that clinical and histological presentation of the EC reflects the genetic and epigenetic alterations affecting mainly PTEN, PIK3CA, KRAS, CTNNB1 and TP53 genes, or leading to microsatellite instability. However, these changes are variably present in both types of EC; therefore dual division of EC has appeared very rigid. The novel classifications should represent an integrated system which also incorporates the results of the gene expression analyses and multiparallel DNA sequencing. Based on these findings EC were divided into four molecular categories: a) POLE/ultra mutated; b) hyper mutated microsatellite instable; c) "copy number low" d) "copy number high" serous-like carcinoma. This division better reflects the biological characteristics of each EC and represents a base for the individual therapy.
Keywords: endometrium - carcinoma - immunohistochemistry - genetics..