Use of transvaginal sonography in the evaluation of endometrial hyperplasia and carcinoma.

Published studies relating to the use of transvaginal sonography (TVS) in the evaluation of endometrial hyperplasia and carcinoma were reviewed. Approximately 80 percent of all curettage procedures performed for postmenopausal bleeding result in benign diagnoses, therefore, if a noninvasive modality such as TVS can be accurately used to determine endometrial thickness measurements below which pathology is less likely, sampling may be avoided. The largest study evaluating endometrial measurements in postmenopausal women with bleeding, known as the Nordic trial, found that for a cut-off value of < or = 4 mm, 96 percent sensitivity and 68 percent specificity was achieved. Another study evaluated endometrial echomorphology in addition to measurement and found that the combined approach improved the predictability of pathologic findings. TVS may also be used to assess the depth of myometrial invasion in patients already diagnosed histologically with endometrial carcinoma. Although MRI is considered the established tool in the presurgical evaluation of the patient with carcinoma, TVS was found to perform only slightly less accurately than MRI. The published studies regarding TVS and/or MRI are reviewed. Finally, the use of TVS in conjunction with a new modality, sonohysterography, in the evaluation of patients on tamoxifen therapy, is discussed. Although the published cut-off values for endometrial thickness measurements do not apply to this group of patients, a procedure whereby sterile saline is injected into the uterine cavity, via a thin catheter, provides additional information regarding endometrial contours. Once the procedure is performed, the supposed complex endometrial echo seen on TVS is often found to actually be located in the subendometrial myometrium and the endometrium itself is thin and regular. The role for TVS is well established in the search for endometrial hyperplasia and carcinoma, as well as evaluating the presence of myometrial invasion once the diagnosis is made.