Reassessment of myometrial invasion in endometrial carcinoma.

Abstract

To assess different methods of measuring the depth of myometrial invasion in endometrial carcinoma as a prognostic factor. Eighty-eight cases of stage I or II endometrial carcinoma treated initially by hysterectomy between 1979-1989 were reviewed histologically. Three methods of measuring myometrial invasion were evaluated: 1) percentage of invaded tumor thickness to whole thickness of myometrium, 2) percentage of whole tumor thickness to total thickness of tumor and myometrium, and 3) distance from the tumor-myometrial junction to the uterine serosa. We evaluated the effect of several factors on prognosis by multivariate analysis using Cox regression models. Myometrial invasion determined by these three measurement methods was associated significantly with survival in a univariate analysis. When myometrial invasion assessed by each method and other prognostic factors were entered into a multivariate model, the distance from the tumor-myometrial junction to the uterine serosa, lymph-vascular space invasion, and cervical stromal involvement were identified as independently significant prognostic factors. This method of evaluating myometrial invasion by measuring the distance from the tumor-myometrial junction to the uterine serosa was most useful as a correlate with survival.