Contribution of ultrasonography to endometrial cancer screening in patients with hereditary nonpolyposis colorectal cancer/Lynch syndrome.

OBJECTIVES: Screening for endometrial cancer is recommended in women at risk for hereditary nonpolyposis colorectal cancer/Lynch syndrome. No screening tool has been validated. The objective of this study was to assess the performance of ultrasonography used to screen for atypical hyperplasia and cancer in women at risk for hereditary nonpolyposis colorectal cancer/Lynch syndrome. Endometrial biopsy was the reference standard.

MATERIALS AND METHODS: Of 85 women with mismatch repair gene mutations or Amsterdam II criteria who were studied prospectively at our institution, 58 had 96 paired ultrasound-biopsy evaluations and were included in the study. Transvaginal or transabdominal ultrasonographic finding was considered normal if no polyps or intrauterine abnormalities were seen and if the maximum endometrial thickness was less than 4 mm in postmenopausal women not receiving hormonal replacement therapy or less than 6 mm in other women. Endometrial biopsy results were categorized as not interpretable, normal, or showing atypical hyperplasia or cancer. Sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio of ultrasonography were computed.

RESULTS: The 58 patients had a mean age of 42.5 years and a median follow-up duration of 51.4 months (range, 17-106 months; 246 patient exposure years). Cancer was diagnosed in 2 patients. Ultrasonography had 100% sensitivity and 100% negative predictive value, 2.2 positive likelihood ratio, and 0 negative likelihood ratio. No interval cancers occurred.

CONCLUSIONS: Ultrasonography had high sensitivity and an excellent negative likelihood ratio in this study. Further studies are needed, and ultrasonography should be compared with clinical follow-up, diagnostic hysteroscopy, or endometrial biopsy alone.