Endometrial carcinoma: the relevance of cervical cytology. In patients with endometrial carcinoma, preoperative identification of poor prognostic factors is helpful in planning therapy. Extended surgical staging, including pelvic and periaortic node dissection, is indicated in patients with deep myometrial invasion or high-grade tumor, or when other risk factors for extrauterine spread are present. In this study, cervical cytology was reviewed in 86 patients with endometrial carcinoma, all of whom underwent surgical staging, to correlate the cytologic results with surgical and pathologic findings. Cervical cytology was normal in 20 patients (23%), whereas suspicious or malignant endometrial cells were present in 23 and 43 cases (27 and 50%), respectively. Suspicious or malignant cervical cytology was associated with deeper myometrial invasion (P = .011), higher postoperative tumor grade (P = .006), positive peritoneal washings (P = .012), and more advanced stage by International Federation of Gynecology and Obstetrics criteria (P = .024). When compared with patients with normal cervical cytology, those who had malignant endometrial cells had over twice the risk of deep myometrial invasion (67 versus 30%), twice the risk of grade 2 or 3 tumor (60 versus 30%), and three times the risk of positive peritoneal washings (33 versus 10%). Seventy-four percent of patients with malignant cervical cytology were stage IC or more. In contrast, 70% of patients with normal cervical cytology were stage IA or IB. Patients with endometrial carcinoma who have malignant endometrial cells detected by cervical cytology are at increased risk of having a deeply invasive, high-grade, advanced-stage tumor, and therefore are more likely to require extended surgical staging. 