Stromal invasion in endometrial adenocarcinoma.

The ability to predict myometrial invasion by endometrial adenocarcinoma is useful for preoperative treatment purposes. The presence of stromal invasion is one possible method of predicting myometrial invasion, but criteria for the presence of stromal invasion have been lacking. Recently, criteria for its detection were proposed. We evaluated the validity of the proposed criteria in two conditions: (1) atypical hyperplasia (119 cases) and (2) endometrial adenocarcinoma Stage I, grade 1 (83 cases). Adenocarcinoma without stromal invasion according to the criteria of Kurman and Norris was present in 43 cases and adenocarcinoma with stromal invasion was present in 40 cases. This series demonstrated the ability of prehysterectomy endometrial sampling to predict the probability of myometrial penetration. In addition, none of our patients without stromal invasion in the resected uterus had myometrial penetration and no metastases have occurred. In those showing stromal invasion in the excised uterus, the myometrium was invaded in 34 of 51 cases (67%). Since myometrial penetration was not present when there was no stromal invasion in the resected uterus, stromal invasion deserves further evaluation and should be considered in future classification of endometrial adenocarcinoma.