CT of intramural endometrial carcinoma: contrast enhancement is essential

The accuracy of computed tomography (CT) in recognizing early stage endometrial carcinoma was assessed in a prospective study in 10 patients in whom macroscopic and microscopic findings of the surgical specimen were correlated with the CT findings. In no instance was endometrial carcinoma confined to the uterine wall demonstrated on a precontrast examination. However, after intravenous infusion of 300 ml diatrizoate 30%, all seven carcinomas involving one-third or more of the thickness of the uterine wall were clearly demonstrated as hypodense lesions. In three patients the center of the hypodense lesions was significantly more enhanced and this was found at surgery to represent less necrotic tumor. Three carcinomas with lesser intramural extent were still invisible after contrast infusion. Because of slow contrast material accumulation in the myometrium and a delayed washout, the optimum time for scanning appears to be immediately after termination of the infusion when the bladder is not yet densely opaque since this may cause disturbing artifacts. The depth of myometrial invasion by endometrial carcinoma is an important prognostic factor in the disease and the CT demonstration of tumor extent may prove to be valuable in optimizing the selection of surgical and/or radiotherapeutic procedures.