From the Guidelines
To rule out endometrial cancer, an office endometrial biopsy is the most definitive initial diagnostic test, with a high sensitivity and specificity, as reported in the 2018 study by the National Comprehensive Cancer Network 1. This procedure can be performed using a thin suction device called a Pipelle, and it collects a small tissue sample from the uterine lining for microscopic examination. The 2018 guidelines from the National Comprehensive Cancer Network suggest that if the endometrial biopsy is negative in a symptomatic patient, a fractional dilation and curettage (D&C) under anesthesia should be performed to rule out endometrial cancer 1. Some key points to consider when ordering diagnostics for endometrial cancer include:
- The use of transvaginal ultrasound to measure endometrial thickness, with a cut-off point of 3 or 4 mm, as suggested by Timmerman et al. 1
- The potential use of hysteroscopy with biopsy as a final step in the diagnostic pathway, particularly if the patient has persistent or recurrent undiagnosed bleeding 1
- The importance of considering risk factors such as abnormal vaginal bleeding, obesity, diabetes, or a family history of endometrial or related cancers when determining the need for diagnostic testing
- The potential use of additional imaging studies like MRI, CT scans, or PET scans to assess the extent of disease if cancer is confirmed or strongly suspected 1
From the Research
Diagnostics for Endometrial Cancer
To rule out endometrial cancer, several diagnostics can be ordered, including:
- Transvaginal ultrasound (TVUS) to measure endometrial thickness (ET) 2, 3, 4, 5, 6
- Endometrial sampling, such as office hysteroscopy-guided endometrial sampling or blind sampling 2, 3, 4
- Hysteroscopy with dilation and curettage (D&C) if blind sampling does not reveal endometrial hyperplasia or malignancy 3
- Pipelle biopsy, although it may not detect all cases of atypical hyperplasia or focal adenocarcinoma 4
Endometrial Thickness Cutoff Values
The cutoff values for endometrial thickness vary, but common values include:
- 4 mm for postmenopausal women with postmenopausal bleeding (PMB) 2, 3, 4, 5, 6
- 5 mm for premenopausal women during the early proliferative phase of the cycle 4
- 3 mm as a potential threshold to maximize sensitivity, although this may not be cost-effective 6
Diagnostic Approach
The diagnostic approach may vary depending on the patient's symptoms and risk factors, including:
- Postmenopausal women with PMB: TVUS to evaluate ET, followed by endometrial sampling if ET is 4 mm or greater 2, 3
- Postmenopausal women without PMB: TVUS to evaluate ET, but arbitrary endometrial sampling is not recommended unless there are other risk factors 2
- Premenopausal women with abnormal uterine bleeding: TVUS to evaluate ET, followed by endometrial sampling if ET is 5 mm or greater 4