Abstract
Objective : To investigate the clinicopathological characteristics of cases with endometrial cancer that could not be diagnosed by endometrial curettage.
Study Design : Between 1983 and 2012, we retrospectively analyzed the data of 12 cases in which endometrial cancer was detected by endometrial cytology but could not be diagnosed by endometrial curettage. We analyzed the clinical courses, cytological features, pathological findings, and outcomes of the cases.
Results : The false-negative rate of curettage for the diagnosis of endometrial cancer was 1.4% (12/880 cases). Histopathological examination showed that the cancer lesions in nearly half of the cases were localized on the endometrial surface ; 9 cases had stageⅠ disease, 2 had stageⅢ disease, and 1 had stageⅣ disease. The distribution of the histological types was as follows : endometrioid, 8 cases ; serous, 2 cases ; mucinous, 1 case ; carcinosarcoma, 1 case. Cytologically, well-differentiated endometrioid adenocarcinoma was composed of slightly atypical cells arranged in sheet-like clusters. By contrast, serous adenocarcinoma was composed of high-grade malignant cells arranged in papillary clusters. Of the total, 3 patients died of recurrent disease. The 5-year overall survival rate was 75%.
Conclusions : Endometrial cancer undiagnosed by curettage can be divided into two types, early-stage well-differentiated endometrioid adenocarcinoma and superficial serous adenocarcinoma potentially complicated by an extrauterine lesion. Endometrial cytology may be helpful for differentiating between the two types.
