[Proliferative activity of normal endometrial cells, endometrial hyperplasia cells and endometrial cancer cells using the monoclonal antibody to PCNA].

PCNA (Proliferating Cell Nuclear Antigen) index was studied by using an immunohistochemical technique in normal endometrium (n = 44), endometrial hyperplasia tissue (n = 12) and endometrial carcinoma (n = 60). In normal endometrial tissues, the PCNA index in the late proliferative phase (n = 11, 26.8 +/- 2.7% (mean +/- SE)) was the highest, and showed a significantly higher value than those of the early-mid secretory phase (n = 7, 12.5 +/- 3.4%, p < 0.01), late secretory phase (n = 11, 0.2 +/- 0.1%, p < 0.001), early proliferative phase (n = 7, 6.4 +/- 2.9%, p < 0.001) and postmenopausal endometrium (n = 8, p < 0.001). The mean PCNA index of premenopausal endometrial carcinoma (n = 17) was 17.1% and was not significantly higher than those of the proliferative phase and endometrial hyperplasia. Postmenopausal endometrial carcinoma (n = 43) presented a mean PCNA index of 19.9%, which was significantly higher than that of normal postmenopausal endometrium (p < 0.005). There was a clear relationship between the PCNA index and nuclear grade, cervical involvement, muscle invasion, lymph-vascular space involvement and lymphnode metastasis, respectively. There was a statistically significant difference in survival between a PCNA index of less than 25% and a PCNA index of 25% or above (p < 0.05). These results suggest that PCNA immunoreactivity in endometrial carcinoma cells may be clinically useful in predicting and/or determining the prognosis, and/or the necessity of adjuvant therapy.