[Amplification and expression of c-erbB2 oncogene in normal, hyperplastic, and malignant endometria]

To study the correlation of development and survival with amplification of c-erbB2 oncogene in endometrial carcinoma.

The amplification and expression of c-erbB2 oncogene were determined from formalin-fixed, paraffin-embedded tissues of 25 normal, 31 hyperplastic, and 72 malignant samples of the endometrium in 128 patients, using differential polymerase chain reaction (DPCR) and an immunohistochemical technique.

Amplified c-erbB2 (2 to 12 copies) were found in two of 25 (8.0%) normal, 15 of 31 (48.4%) hyperplastic, and 45 of 72 (62.5%) malignant samples. When the results of DPCR were compared with those of the immunohistochemical method, the negative findings concide well with one another, i.e., nonamplification was associated with the absence of immunoreactivity. It was noted that the amplified c-erbB2 was found more significantly in complex and a typical hyperplasias than in simple hyperplasias. The high-level c-erbB2 amplification (at least five copies) was significantly correlated with the histological grade of endometrial carcinoma and vascular or lymphatic invasion. No correlation was seen between c-erbB2 amplification and overall survival in the present group of patients.

The amplified c-erbB2 may play a potential role in the early development of some endometrial carcinomas. The high-level c-erbB2 amplification may identify a subset of aggressive endometrial carcinoma that involves vascular or lymphatic invasiveness and poor cell differentiation playing the role of a marker for clinical prognosis.