Background: The value of DNA image cytometry in the differential diagnosis of endocervical adenocarcinoma was tested on a series of 65 cases of normal endocervical cells (n = 25), inflammatory changes (n = 18), and endocervical adenocarcinoma (n = 22).
Methods: The investigation was performed on gynecologic routine smears by using a television image analysis system MIAMED-DNA (Leica, Wetzlar, Germany), combined with an automated Leica Medilux microscope. First, the Papanicolaou stained specimens were rescreened, and the x/y coordinates of at least 150 endocervical nuclei were stored per case by using a scanning program. After restaining according to Feulgen, the epithelial cells were relocalized and the DNA content, and the nuclear area were determined. The DNA content of 25-30 squamous epithelial cells of intermediate type served as an internal standard for the normal diploid value in each case. Various DNA cytometric parameters and the mean nuclear area were calculated. For statistical analysis, the cases of adenocarcinoma (n = 22) were defined as positive, and the cases with normal endocervical epithelium or inflammatory changes (n = 43) were defined as negative.
Results: The presence of nuclei with a DNA content greater than 9c was observed exclusively in adenocarcinoma (sensitivity, 95.9%; specificity, 100%), indicating that this parameter is suited best for the differentiation between malignant and nonmalignant endocervical epithelium. High sensitivity rates at a specificity level of 100% also were calculated for the 2.5cER (95.5%), the mean ploidy (90.9%), 5cER (90.9%), and the diploid deviation quotient (90.9%). For the 2cDI (86.4%), the entropy (81.8%) and the ploidy imbalance (77.3%) lower values were obtained.
Conclusions: DNA single cell cytometry represents a highly relevant tool in the identification of malignant transformation in endocervical lesions that could be used as a complementary diagnostic method in cytologically difficult cases. Investigations on endocervical adenocarcinoma in situ should be performed in the near future.