Determination of reliable histological features associated with early triploidy using DNA image cytometry.

In order to determine reliable histological features characterizing triploidy, the following features were examined and graded by three pathologists on 46 early abortion specimens: hydropic swelling of the villi, cisterns, villous scalloping, trophoblastic hyperplasia with syncytial vacuolization, single cytotrophoblastic cells in villous stroma, trophoblastic inclusions, microcalcifications and fibrosis. At the same time, the DNA content of the 46 specimens was quantified cytophotometrically using the CAS 200 image analyzer, in order to confirm or not the diagnosis of triploidy. Triploidy was confirmed in 45.7%, and in the triploid group, the grading of three features differed significantly from the non triploid group i.e. cisterns (p < 0.001), trophoblastic hyperplasia (p < 0.05) and trophoblastic inclusions (p < 0.05). Using these three features we were able to give a triploid score per slide which represents the sum of the grades of each of these three features. The minimum score obtained was 0, the maximum was 6. The average of these scores in the triploid group was 3.095, and 1.45 in the non triploid group (p < 0.001). This scoring method on the three significant features (cisterns, trophoblastic hyperplasia and trophoblastic inclusions) appears to be useful to classify an abortion specimen as triploid or not, and to select the specimens for which a DNA quantification may be necessary.