Flow cytometrical DNA measurements in endometrial hyperplasias. A prospective follow-up study after abrasio only or additional high-dose gestagen treatment.

As part of a prospective study on endometrial hyperplasias the DNA content in individual cells was measured by flow cytometry in 109, 35 and 12 cases of cystic glandular, adenomatous and atypical hyperplasias respectively. About 20% of all types of hyperplastic endometria revealed a non-diploid DNA index compared to 6% in normal endometria and 29% in well differentiated carcinomas. Increasing severity of hyperplasia was accompanied by increased proliferative activity as reflected by increased S-phase-and (S + G2)-fractions. The findings emphasise a previous suggestion that all types of hyperplasias are predecessors to endometrial carcinomas. Examination after 3 months following abrasio alone or in combination with high-dose gestagen treatment revealed a still high frequency of non-diploid cells. This was the case in endometria without histologic signs of hyperplasia as well as in those still demonstrating hyperplastic changes. Hypothetically chromosomal aberrations could be the main reason for the development of hyperplasias.