Two cases of low-grade endometriod carcinoma associated with undifferentiated carcinoma of the uterus (dedifferentiated carcinoma): a molecular study.

Dedifferentiated carcinoma (DC) is an uterine neoplasm containing both low-grade endometrioid carcinoma (LGEC) and undifferentiated carcinoma (UC). DC is an aggressive tumour even when the UC component represents only 20% of the entire neoplasm. In this paper, two cases DCs at different stages of development, in 61- and 83-year-old women respectively were reported. In addition, in these uterine malignancies microsatellite instability (MSI) and loss of heterozygosity (LOH) were investigated in order to explain its aggressive behavior, in both components. Case #1 presented metastases at diagnosis, while case #2 was at a lower stage. LGEC component was invasive in case #1 and intramucous in case #2. In both cases, UC components were characterized by a high degree of instability, in accordance of its aggressive behaviour and its architectural heterogeneity. Further studies with more numerous cases are mandatory to confirm these data.