Should a patient over 40 years old with abnormal uterine bleeding and concomitant myoma (uterine fibroids) undergo endometrial curettage or biopsy before considering a hysterectomy?

Endometrial Sampling Before Hysterectomy in Women ≥40 Years with Abnormal Uterine Bleeding and Fibroids

Yes, endometrial biopsy or curettage is mandatory before proceeding with hysterectomy in patients 40 years and older with abnormal uterine bleeding, even when fibroids are present, to rule out endometrial cancer and uterine sarcoma. 1, 2

Guideline-Based Rationale

The American College of Radiology 2024 guidelines explicitly state that all postmenopausal patients with abnormal uterine bleeding must undergo workup to rule out endometrial cancer prior to proceeding with any treatment, including hysterectomy. 1 While these guidelines specifically address postmenopausal women, the principle extends to perimenopausal women aged 40 and above due to increasing malignancy risk with age. 3

Age-Stratified Cancer Risk

• The risk of unexpected uterine sarcoma in women undergoing surgery for presumed fibroids is 2.94 per 1,000 overall, but increases dramatically with age to 10.1 per 1,000 in women aged 75-79 years. 1
• This age-dependent risk escalation justifies mandatory endometrial sampling in all women 40 years and older before hysterectomy. 3
• Fibroids and uterine sarcoma can present similarly on imaging, and there is no way to definitively distinguish them without tissue diagnosis. 1

Recommended Diagnostic Algorithm

Step 1: Initial Endometrial Assessment

• Office endometrial biopsy using Pipelle or similar device is the first-line approach, with sensitivity of 99.6% for detecting endometrial carcinoma. 4
• This can be performed as an outpatient procedure before scheduling hysterectomy. 5

Step 2: If Initial Sampling Inadequate

• Hysteroscopy with directed biopsy should be performed if blind sampling is inadequate, inconclusive, or if focal lesions are suspected. 4
• Hysteroscopy allows direct visualization to distinguish between endometrial pathology, polyps, and submucosal fibroids with 100% sensitivity. 4

Step 3: Proceed Based on Results

• If biopsy is negative for malignancy: Proceed with hysterectomy using the least invasive route (vaginal > laparoscopic > abdominal). 1
• If malignancy is detected: Hysterectomy becomes the definitive treatment with appropriate oncologic staging. 2

Critical Clinical Pitfalls

Do Not Assume Fibroids Explain All Bleeding

• Even when fibroids are clearly present on imaging, they do not exclude concurrent endometrial cancer or hyperplasia. 1
• The presence of fibroids should never be used as justification to skip endometrial sampling in women ≥40 years with abnormal bleeding. 3

Do Not Rely on Imaging Alone

• MRI can help distinguish fibroids from sarcoma but cannot definitively diagnose malignancy without tissue. 1
• Continued fibroid growth or bleeding after menopause should raise suspicion for uterine sarcoma. 1

Do Not Proceed with Minimally Invasive Procedures Without Tissue Diagnosis

• Uterine artery embolization and other minimally invasive treatments require negative endometrial biopsy first. 1
• Given the increased risk of uterine malignancy in women over 40, all patients with abnormal uterine bleeding should undergo workup to rule out endometrial cancer prior to proceeding with UAE or other procedures. 1

Evidence Quality Considerations

The 2024 ACR Appropriateness Criteria represents the most recent and authoritative guideline on this topic. 1 While one 2024 research study questioned the concordance between preoperative endometrial biopsy and final hysterectomy pathology (Kappa = 0.108), finding low agreement, 5 this actually strengthens the argument for mandatory sampling—it demonstrates that clinical assessment and imaging alone are insufficient, and tissue diagnosis remains essential despite imperfect sensitivity.

An older 1989 study suggested routine endometrial sampling prior to hysterectomy was not necessary, 6 but this predates modern understanding of age-stratified cancer risk and contradicts current guideline recommendations. The contemporary standard prioritizes patient safety through mandatory malignancy exclusion. 1, 2, 3

Practical Implementation

• Timing: Perform endometrial sampling during the preoperative workup, not at the time of hysterectomy. 5
• Method: Office-based Pipelle biopsy is adequate for most cases and avoids the need for anesthesia. 4, 5
• Documentation: Document that malignancy has been excluded before proceeding with hysterectomy for presumed benign fibroids. 3
• Patient counseling: Inform patients that this step is mandatory regardless of fibroid size or imaging findings. 1