Postmenopausal bleeding is a symptom that can announce the presence of a gynecologic malignancy. In this column, we will discuss the important considerations to make in the work-up of this symptom.
Roughly 10% of women will present for evaluation of postmenopausal bleeding.1 More than a third of these women will have benign pathology, with the incidence of endometrial cancer in this group at only about 5%.2 Other gynecologic malignancies should be considered as well, including cervical, vaginal, vulvar, and more rarely, those of the fallopian tubes or ovaries.
Use of ultrasound
Ultrasound is a commonly performed initial approach to work-up because of its noninvasive nature. Transvaginal ultrasound has a high negative predictive value of 99.4%-100% in ruling out malignancy.3 Among women with postmenopausal bleeding, the risk of cancer is 7.3% if their endometrial lining is 5 mm or greater and less than 0.07% risk if their lining is 4 mm or less. Therefore, this cutoff dimension is typically used to triage patients to additional sampling.
If ultrasound is performed on postmenopausal women who are asymptomatic (no bleeding), then an endometrial stripe of greater than 11 mm is considered justification for further work-up and is associated with a 6.7% risk of endometrial cancer.4 If the ultrasound reveals intracavitary lesions, a sonohysterogram would be preferred to characterize intrauterine pathology. In fact, sonohysterography is superior to transvaginal ultrasound (with a sensitivity of 80% vs. 49%, respectively) in detecting endometrial polypoid lesions.5 Preoperative identification of an intracavitary lesion may assist in selecting the best sampling technique (blind vs. hysteroscopy-guided approach).
If an ultrasound reveals a thickened or unevaluable endometrial stripe or if the clinician chooses to proceed directly with diagnostic confirmation, several options for endometrial sampling exist, including office-based or operative procedures, as well as blind or visually guided ones. Endometrial pipelle biopsy, D&C without hysteroscopy, endometrial lavage, and endometrial brush biopsy all constitute “blind” sampling techniques. Targeted biopsy techniques include hysteroscopy D&C and saline infusion sonohysterography–guided biopsy.
Although D&C may be considered the gold standard of diagnostic sampling techniques, it should be noted that 60% of these procedures sample less than half of the endometrium.6 When used in conjunction with hysteroscopy, the sensitivity in detecting cancer is high at 97% with a specificity of 93%-100%.7
While some patients are candidates for office-based procedures, D&C often requires regional or general anesthesia and is frequently performed in a hospital-based environment or surgical center. This may be most appropriate for patients who have had failed office attempts at sampling, have multiple medical comorbidities that limit the feasibility of office-based procedures (such as morbid obesity), or have severe cervical stenosis. D&C is associated with an increased risk for uterine perforation, compared with outpatient sampling procedures.
The need to go to the operating room rather than to an ambulatory setting also may increase the costs borne by the patient. The advantages of D&C include the potential for large-volume sampling and the potentially therapeutic nature of the procedure in cases of benign pathology.
Office-based sampling techniques include those using a pipelle, those employing an endometrial brush, and those guided by saline infusion sonohysterography. If performed in the office, they require minimal or no cervical dilation, are associated with a lower risk of perforation or adverse reaction to anesthesia, and usually have lower costs for patients.
Endometrial pipelle biopsies are a very effective diagnostic tool when there is global, endometrial pathology; they have a sensitivity of 83% in confirming cancer.8 It is an inexpensive and technically straightforward technique that can be easily performed in an office setting.
However, when the endometrial lining is atrophied, alternative tools may provide superior results. Endometrial brushes have been shown to be 33% more successful in collecting adequate samples,compared with pipelles, because they sample a larger endometrial surface area.9
There is ongoing development of sampling techniques, such as endometrial lavage or the combination of saline infusion sonohysterography and endometrial biopsy.10 However, future studies regarding accuracy, cost, and patient acceptability are needed before these techniques are translated to the clinical setting.