A New Diagnostic Test for Endometrial Cancer?: Cytology Analysis of Sonohysterography Distention Media

Abstract

During saline-infused sonohysterography (SIS), the distension fluid is typically discarded. If cytology analysis could identify those patients with endometrial cancer, many women would be spared from further procedures. Thirty consecutive patients with clinical stage I or II endometrial adenocarcinoma were prospectively recruited preoperatively. Saline-infused sonohysterography was performed by instilling 5 mL of saline, withdrawing and sending for analysis. Saline was reinfused until complete SIS images were obtained and sent separately for cytology. Of the 30 women enrolled, SIS was technically successful in 29. Demographics included mean age (60.5 ± 6.99 years), body mass index (35.55 ± 8.18 kg/m), endometrioid histology (76%), and grade (grade 1, 67%). Prestudy diagnostic method included biopsy (70%), dilatation and curettage (17%), and hysteroscopy (10%). Adequate cytology specimens were obtained in 66% of the 5 mL flushes and 72% of the complete SIS collections. Of adequate specimens, the sensitivities to detect endometrial cancer for the 5-mL, complete, and combined fluid samples were 26% (95% confidence interval, 9%-51%), 36% (17%-59%), and 42% (22%-63%). Sensitivity based on the whole study sample (N = 30) was 33% (17%-53%). Statistical significance was not found in the association between a positive test and age, body mass index, grade, diagnostic method, or volume instilled or aspirated. Most patients with early endometrial cancer can undergo SIS procedures with adequate cytology specimens obtained from distention media. However, the sensitivity is low, and refinements are necessary before utilizing as a diagnostic test. In cases with positive results, the patient may be able to avoid other costly and painful procedures.