SAN FRANCISCO – Close adherence to guidelines for deciding when to do endometrial biopsies in women with abnormal uterine bleeding could mean ordering biopsies in 88% of perimenopausal women with bleeding, according to Dr. Rebecca Jackson.
Irregular uterine bleeding is "incredibly common," endometrial cancer is "relatively common," and models to predict which women with abnormal bleeding are at risk for endometrial cancer "have been examined and are not useful," said Dr. Jackson, professor of obstetrics and gynecology at the University of California, San Francisco, and chief of obstetrics and gynecology at San Francisco General Hospital. Without much data to go on, "we’re left with expert opinion," she said.
She offered the following approach employed at her institution in a presentation at a conference on women’s health sponsored by the university. "We’re heartened to see that UpToDate has the same approach," Dr. Jackson said, referring to the digital evidence-based clinical decision support tool.
American College of Obstetricians and Gynecologists Practice Bulletin 128 on the Diagnosis of Abnormal Uterine Bleeding in Reproductive-Aged Women recommends that endometrial tissue sampling be done in patients with abnormal uterine bleeding who are older than 45 years and in younger patients who have a history of unopposed estrogen exposure, failed medical management, and persistent abnormal uterine bleeding (Obstet. Gynecol. 2012;120:197-206).
During an average 4-year perimenopause, however, only 12% of women completely stop menstruating; 70% have short, irregular menses; and 18% have longer, heavier menses, studies have shown (Int. J. Fertil 1967;12:77-126; Acta Obstet. Gynecol. Scand. 1966;45:320-51).A close application of the ACOG guidelines could mean biopsies in all but 12% of perimenopausal women, she said.
Dr. Jackson said she takes endometrial biopsies in all postmenopausal women with any abnormal uterine bleeding except for bleeding that starts 4-6 months after initiating hormone therapy. Approximately 10% of postmenopausal women with bleeding have cancer. "That’s a very high pretest probability when you’re talking about cancer, way higher than when you think about an abnormal mammogram," she said. Offering a postmenopausal patient a choice between a biopsy and a transvaginal ultrasound is reasonable as long as either procedure is available quickly and the patient understands that she still may need an endometrial biopsy after an ultrasound.
In women with a recent onset of irregular bleeding, don’t jump to a biopsy too quickly for this very common phenomenon. "Consider treating her, and if it normalizes, there’s no need for an endometrial biopsy," she said.
She recommended a low threshold for biopsy in women older than 50 years who have recurrent irregular bleeding because the risk of cancer is going up with age, but consider not getting a biopsy if the periods are light and spacing out. Periods that happen every 2-3 months and last 2-3 days are "not a very worrisome pattern," she said. Endometrial cancer presents most commonly with menometrorrhagia and sometimes with intermenstrual bleeding, but rarely with regularly timed menses.
Dr. Jackson said she biopsies women aged 45-50 years if they have recurrent irregular bleeding plus at least one risk factor for endometrial cancer or they’ve had more than 6 months of menometrorrhagia.
In younger women, consider a biopsy if they’ve had a "long history" of untreated anovulatory bleeding, which could be 2 years or 5 years, she suggested. "We have a hard time getting consensus on that [definition of] long," she noted.
A Pap smear result showing atypical glandular cells or endometrial cells would be another reason to biopsy if the Pap smear was not done at the time of menses.
An endometrial biopsy is not perfectly sensitive, so "keep your radar up" even if the biopsy result is negative, and evaluate further if abnormal bleeding persists, she said.
Her search of the literature on less-aggressive strategies for endometrial biopsies turned up just one small prospective cohort study of 1,000 women with abnormal uterine bleeding who were eligible for endometrial biopsy under ACOG guidelines. Biopsies were performed in only 570 women who were postmenopausal or who had at least one risk factor for endometrial cancer (such as obesity or polycystic ovarian syndrome), and all were followed for 2 years. None of the women who did not undergo biopsy developed cancer or hyperplasia, but the study was underpowered to assess outcomes in those women, she said (J. Reprod. Med. 2001;46:831-4).
Dr. Jackson reported having no relevant financial disclosures.
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