The diagnostic value of power Doppler measurements in the endometrium of women with postmenopausal bleeding

Ultrasound detection of endometrial cancer in women with postmenopausal bleeding: Systematic review and meta-analysis

OBJECTIVE

To assess the performance of endometrial thickness (ET) cut-offs for detecting endometrial cancer (EC) in women with postmenopausal bleeding (PMB) and evaluate the clinical utility of additional ultrasound measures such as endometrial volume (EV), vascular flow index (VFI), vascularization index (VI), and uterine artery flow index (FI).

METHODS

Clinicaltrials.gov and MEDLINE database via PubMed were queried for studies published between 1/1990 and 3/2016 using specific MeSH terms. Original, peer-reviewed cohort studies reporting EC outcomes and specific ultrasound findings by PMB status were included.

RESULTS

Study design, country, clinical setting inclusion/exclusion criteria, aggregate study-level demographic and clinical data were extracted from 44 studies including 17,339 women with PMB and 1341 cases of EC (7.7%). In women with PMB and EC (n = 417), pooled mean ET was 16.4 mm (95% CI, 14.8-18.1 mm). In women with PMB without EC, pooled mean ET was 4.1 mm. 31 studies reported outcomes using different ET cut-off values ranging from 3 to 20 mm. Compared to ≥3 or 4 mm, a cutoff of ≥5 mm had similar sensitivity (96.2, 95%CI 92.3, 98.1) with improved specificity for EC (51.5, 95%CI 42.3-60.7), allowing to reduce the rate of invasive workup for PMB by 17%. EV, VI, VFI, and FI were significantly correlated with EC, but performance of specific cut-offs was not analyzed due to limited data.

CONCLUSION

Among women with PMB mean ET is substantially higher in women with EC compared to those without EC. An ET cutoff of ≥5 mm shows an acceptable tradeoff between sensitivity and specificity for diagnosis of EC.

Association of Endometrial Cancer Risk With Postmenopausal Bleeding in Women: A Systematic Review and Meta-analysis

IMPORTANCE

As the worldwide burden of endometrial cancer continues to rise, interest is growing in the evaluation of early detection and prevention strategies among women at increased risk. Focusing efforts on women with postmenopausal bleeding (PMB), a common symptom of endometrial cancer, may be a useful strategy; however, PMB is not specific for endometrial cancer and is often caused by benign conditions.

OBJECTIVE

To provide a reference of the prevalence of PMB in endometrial cancers and the risk of endometrial cancer in women with PMB.

DATA SOURCES

For this systematic review and meta-analysis, PubMed and Embase were searched for English-language studies published January 1, 1977, through January 31, 2017.

STUDY SELECTION

Observational studies reporting the prevalence of PMB in women with endometrial cancer and the risk of endometrial cancer in women with PMB in unselected populations were selected.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers evaluated study quality and risk of bias using items from the Newcastle-Ottawa Quality Assessment Scale and the Quality Assessment of Diagnostic Accuracy Studies tool. Studies that included highly selected populations, lacked detailed inclusion criteria, and/or included 25 or fewer women were excluded.

MAIN OUTCOMES AND MEASURES

The pooled prevalence of PMB in women with endometrial cancer and the risk of endometrial cancer in women with PMB.

RESULTS

A total of 129 unique studies, including 34 432 unique patients with PMB and 6358 with endometrial cancer (40 790 women), were analyzed. The pooled prevalence of PMB among women with endometrial cancer was 91% (95% CI, 87%-93%), irrespective of tumor stage. The pooled risk of endometrial cancer among women with PMB was 9% (95% CI, 8%-11%), with estimates varying by use of hormone therapy (range, 7% [95% CI, 6%-9%] to 12% [95% CI, 9%-15%]; P < .001 for heterogeneity) and geographic region (range, 5% [95% CI, 3%-11%] in North America to 13% [95% CI, 9%-19%] in Western Europe; P = .09 for heterogeneity).

CONCLUSIONS AND RELEVANCE

Early detection strategies focused on women with PMB have the potential to capture as many as 90% of endometrial cancers; however, most women with PMB will not be diagnosed with endometrial cancer. These results can aid in the assessment of the potential clinical value of new early detection markers and clinical management strategies for endometrial cancer and will help to inform clinical and epidemiologic risk prediction models to support decision making.

The role of transvaginal power Doppler ultrasound in the differential diagnosis of benign intrauterine focal lesions

PURPOSE

The purpose of this prospective study was to assess the role of power Doppler imaging in the differential diagnosis of benign intrauterine focal lesions such as endometrial polyps and submucous myomas using the characteristics of power Doppler flow mapping.

METHODS

A total of 480 premenopausal patients with abnormal uterine bleeding were evaluated by transvaginal ultrasonography (TVS) searching for intrauterine pathology. Sixty-four patients with a suspicious focal endometrial lesion received saline infusion sonography (SIS) after TVS. Fifty-eight patients with focal endometrial lesions underwent power Doppler ultrasound (PDUS). Three different vascular flow patterns were defined: Single vessel pattern, multiple vessel pattern, and circular flow pattern. Finally, hysteroscopic resection was performed in all cases, and Doppler flow characteristics were then compared with the final histopathological findings.

RESULTS

Histopathological results were as follows: endometrial polyp: 40 (69 %), submucous myoma: 18 (31 %). Of the cases with endometrial polyps, 80 % demonstrated a single vessel pattern, 7.5 % a multiple vessel pattern, and 0 % a circular pattern. Vascularization was not observed in 12.5 % of patients with polyps. Of the cases with submucousal myomas, 72.2 % demonstrated a circular flow pattern, 27.8 % a multiple vessel pattern, and none of them showed a single vessel pattern. The sensitivity, specificity, and positive and negative predictive values of the single vessel pattern in diagnosing endometrial polyps were 80, 100, 100, and 69.2 %, respectively; and for the circular pattern in diagnosing submucous myoma, these were 72.2, 100, 100, and 88.9 %, respectively.

CONCLUSION

Power Doppler blood flow mapping is a useful, practical, and noninvasive diagnostic method for the differential diagnosis of benign intrauterine focal lesions. Especially in cases of recurrent abnormal uterine bleeding, recurrent abortion, and infertility, PDUS can be preferred as a first-line diagnostic method.

Practical Utility of Color Doppler Sonography in the Evaluation of Endometrial Pathology

The sonographic findings and corresponding pathology reports of 83 premenopausal and 55 postmenopausal women were retrospectively reviewed to evaluate the significance of color Doppler imaging in the evaluation of the endometrium. Premenopausal women had flow noted in the single malignancy case and in 16 of 21 (76%) polyps, with 7 polyps (33%) presenting as a vascular pedicle. In postmenopausal women, flow was seen in 3 of 5 (60%) malignancies and 5 of 9 (56%) polyps, with 2 polyps (22%) presenting as a vascular pedicle. Postmenopausal women with thin endometria had flow in 1 of 2 (50%) polyps, while those with thicker endometria had flow in 4 of 7 (56%) polyps and 3 of 5 (60%) malignancies. The data showed that color Doppler imaging was useful in detecting vascular pedicles in endometrial polyps, but it was not otherwise helpful as an independent predictor of malignancy.

Clinical pathway for the evaluation of postmenopausal bleeding with an emphasis on endometrial cancer detection

Postmenopausal bleeding (PMB) accounts for about 5% of all office gynaecology visits. The causes of PMB are varied. Many women with endometrial cancer present with this symptom. Although many investigations are described, the most appropriate approach is often unclear. In a patient with no obvious local cause, the emphasis should be on uterine and adnexal evaluation. Based on a literature review, the evidence favours a conservative approach if the endometrial thickness (ET) is < 4mm, unless there are risk factors. All patients with ET 4 mm should have outpatient endometrial sampling. If this is unsuccessful, then outpatient hysteroscopy with directed biopsy or inpatient hysteroscopy is favoured. The role of ancillary investigations are described.

A thin and regular endometrium on ultrasound is very unlikely in patients with endometrial malignancy

OBJECTIVE

To evaluate the clinical and sonographic features in patients with endometrial malignancy in whom endometrial thickness on ultrasound examination had been recorded in our database to be < 5 mm.

METHODS

This was a retrospective observational study on 187 consecutive patients diagnosed with endometrial malignancy in whom an ultrasound evaluation of the endometrium had been performed in our institution. The characteristics of those patients presenting with an endometrial thickness < 5 mm were analyzed.

RESULTS

The median endometrial thickness was 15 mm: 12 mm for the women who underwent endometrial sampling before ultrasound examination vs. 17 mm in those who did not (P = 0.0086). In 13 women (6.9%), the endometrial thickness recorded in our database was < 5 mm. In 12 of these the measurement was compromised in some way: nine of these patients had undergone endometrial sampling (Pipelle biopsy in one and dilatation and curettage in eight patients) before the ultrasound examination, in two cases, focal malignant lesions were not included in the recorded endometrial thickness and in one, the endometrial thickness was visualized poorly due to myometrial distortion. In only one case was was the endometrium correctly measured to be < 5 mm; this woman had diffuse uterine and endometrial metastases of a breast cancer.

CONCLUSIONS

A thin and regular endometrial line is very reliable for the exclusion of endometrial carcinoma. The suspicion of focal lesions as well as incomplete visualization of the endometrium on sonography should be considered abnormal. Recently performed endometrial sampling makes measurement of the endometrial thickness unreliable.

Imaging in gynecology

This chapter summarizes the diagnostic performance (sensitivity, specificity, positive and negative likelihood ratios) of ultrasound, computer tomography, and magnetic resonance imaging in the diagnosis of various gynecological diseases and tumors. Positron emission tomography is not discussed. Imaging in infertility, in the diagnosis of Mullerian duct anomalies and in gynecological oncology (staging of gynecological cancers, diagnosis of recurrence of gynecological cancer, diagnosis of trophoblastic tumors) is not dealt with. Ultrasound is the first-line imaging method for discrimination between viable intrauterine pregnancy, miscarriage and tubal pregnancy in women with bleeding and/or pain in early pregnancy, for discrimination between benign and malignant adnexal masses and for making a specific diagnosis in adnexal tumors (e.g. dermoid cyst, endometrioma, hemorrhagic corpus luteum, etc.), for diagnosing intracavitary uterine pathology in women with bleeding problems, and for confirming or refuting pelvic pathology in women with pelvic pain. Magnetic resonance imaging can have a role as a secondary test in the diagnosis of adenomyosis, 'deep endometriosis' (e.g. endometriosis in the rectovaginal septum or in the uterosacral ligaments), and in the diagnosis of extremely rare types of ectopic pregnancy (e.g. in the spleen, liver or retroperitoneum).

Value of sonography in the diagnosis of abnormal vaginal bleeding

Abnormal vaginal bleeding is one of the most common presenting complaints in women of any age seeking gynecologic health care. Two of the most frequently used diagnostic tests to investigate the cause of the bleeding are endometrial biopsy and transvaginal sonography. The most worrisome cause of abnormal bleeding is endometrial carcinoma, yet benign etiologies are far more prevalent, including fibroids, polyps, and endometrial atrophy. Endometrial biopsy and transvaginal sonography have equal sensitivities for carcinoma, but sonography is far more effective in diagnosing benign disease. This article reviews the state-of-the-art in the diagnostic evaluation of abnormal vaginal bleeding and analyzes the data, with emphasis on the prevalence of benign and malignant disease as the basis for determining whether sonography or biopsy is more cost-effective in evaluating women with abnormal vaginal bleeding.

Managing women with post-menopausal bleeding

Transvaginal ultrasound examination can reliably distinguish women with post-menopausal bleeding (PMB) who are at low risk of endometrial pathology (endometrial thickness < or =4 mm) from those who are at high risk (endometrium > or =5 mm) and can rule out focally growing lesions in the uterine cavity using saline infusion into the cavity as a negative contrast agent (hydrosonography). The 5 mm cut-off is applicable irrespective of the use of hormone replacement therapy. It is justified to refrain from endometrial sampling in women with PMB and an endometrial thickness of < or =4 mm because the risk of endometrial cancer in these women is low (0.1-1.0%). However, it is not known whether these women need follow-up. About 80% of women with PMB and an endometrium of > or =5 mm have focally growing pathological lesions in the uterine cavity. These should be removed by operative hysteroscopy because dilatation and curettage (D and C) will fail to diagnose and remove a large proportion of these lesions. However, D and C is a reliable diagnostic method for women without focal lesions in the uterine cavity. It is not known whether simple outpatient sampling devices (e.g. Pipelle) are as reliable as D and C in women without focal lesions. A measurement of endometrial thickness is a simple and accurate method for estimating the risk of endometrial cancer. The reliability of ultrasound evaluation of endometrial morphology and/or vascularization for risk estimation of endometrial malignancy remains to be determined.

Ultrasonographic evaluation of the endometrium in postmenopausal vaginal bleeding

Transvaginal ultrasound with SIS is a cost-minimizing screening tool for perimenopausal and postmenopausal women with vaginal bleeding. Its use decreases the need for invasive diagnostic procedures for women without abnormalities, and ultrasound increases the sensitivity of detecting abnormalities in women with pathologic conditions. Vaginal sonography is preferred over uniform biopsy of postmenopausal women with vaginal bleeding because it (1) is a less invasive procedure, (2) is generally painless, (3) has no complications, and (4) may be more sensitive for detecting carcinoma than blind biopsy. Transvaginal sonography is rarely nondiagnostic. Endometrial sampling is less successful in women with a thin endometrial stripe on ultrasound than in women with real endometrial pathologic condition. A limitation of ultrasound is that an abnormal finding is not specific: ultrasound cannot always reliably distinguish between benign proliferation, hyperplasia, polyps, and cancer. Although ultrasound may not be able to distinguish between hyperplasia and malignancy, the next step in the clinical treatment requires tissue sampling. Because of the risk of progression of complex hyperplasia to carcinoma, patients with this finding may benefit from hormonal suppression, dilatation and curettage, endometrial ablation, or hysterectomy, depending on the clinical scenario. The inability to distinguish these two entities based on ultrasound alone should not be seen as a limitation because tissue sampling is required in either case. Occasionally (in 5% to 10% of cases), a woman's endometrium cannot be identified on ultrasound, and these women also need further evaluation. Ultrasonography also may be used as a first-line investigation in other populations with abnormal uterine bleeding. In a multicenter, randomized, controlled trial of 400 women with abnormal uterine bleeding, the investigators found that transvaginal sonography combined with Pipelle endometrial biopsy and outpatient hysteroscopy was as effective as inpatient hysteroscopy and curettage. The subject, included women older than 35 years with PMB, menorrhagia, intermenstrual bleeding, postcoital bleeding, or irregular menses. Transvaginal sonography may be a cost-effective. sensitive, and well-tolerated method to evaluate most women with abnormal bleeding in combination with physical examination and endometrial biopsy and hysteroscopy us indicated. Hysteroscopy is likely to become the new gold standard in the future because of its ability to visualize directly the endometrium and perform directed biopsies as indicated. As office-based hysteroscopy becomes more practical and widespread, the technique may become more cost effective. An evaluation plan using transvaginal sonography as the initial screening evaluation followed by endometrial biopsy or, more likely, hysteroscopy is likely to become the standard of care (Fig. 12). It remains unproven whether certain patients at higher risk for carcinoma should proceed directly to invasive evaluation. Women on tamoxifen with persistent recurrent bleeding, women with significant risk factors for carcinoma, and women with life-threatening hemorrhage comprise this group. Further studies are still necessary to evaluate high-risk patients and determine whether ultrasound or biopsy is really the most cost-effective initial test.

Endometrial blood flow mapping using transvaginal power Doppler sonography in women with postmenopausal bleeding and thickened endometrium

OBJECTIVE

To evaluate the role of transvaginal power Doppler sonography to discriminate between benign and malignant endometrial conditions in women presenting with postmenopausal bleeding and thickened endometrium at baseline sonography.

METHODS

Ninety-one postmenopausal women (median age, 58 years; range, 47-83 years) presenting with uterine bleeding and a thickened endometrium (> or = 5-mm double-layer endometrial thickness) on transvaginal sonography were included in this prospective study. Endometrial blood flow distribution was assessed in all patients by power Doppler immediately after B-mode transvaginal sonography. Three different vascular patterns were defined: Pattern A: multiple-vessel pattern, Pattern B: single-vessel pattern and Pattern C: scattered-vessel pattern. Histological diagnoses were obtained in all cases. No patient taking tamoxifen citrate or receiving hormone replacement therapy was included.

RESULTS

Histological diagnoses were as follows: endometrial cancer: 33 (36%), endometrial polyp: 37 (41%), endometrial hyperplasia: 14 (15%), endometrial cystic atrophy: 7 (8%). Blood flow was found in 97%, 92%, 79% and 85% of cases of carcinoma, polyp, hyperplasia and endometrial cystic atrophy, respectively. A total of 81.3% of vascularized endometrial cancers showed Pattern A, 97.1% of vascularized polyps exhibited Pattern B and 72.7% of vascularized hyperplasias showed Pattern C. Sensitivity and specificity for endometrial cancer were 78.8% and 100%. For endometrial polyp these respective values were 89.2% and 87% and for hyperplasia they were 57.1% and 88.3%.

CONCLUSIONS

Transvaginal power Doppler blood flow mapping is useful to differentiate benign from malignant endometrial pathology in women presenting with postmenopausal bleeding and thickened endometrium at baseline sonography.

Transvaginal color Doppler ultrasonography for prediction of pre-cancerous endometrial lesions

OBJECTIVE

To determine whether measurements of blood flow in endometrial and uterine vessels by transvaginal color Doppler ultrasonography was valuable in the diagnosis of a neoplastic endometrial pathology (hyperplasia and carcinoma) in women with abnormal bleeding.

METHODS

This is a prospective study and included 105 post-menopausal women and 33 pre-menopausal women with abnormal uterine bleeding. All subjects underwent transvaginal color Doppler ultrasonography. We investigated whether obtained results were correlated with histopathological findings.

RESULTS

There was no significant difference in the mean+/-S.D. RI of the left and the right uterine arteries, intramyometrial arteries and endometrial arteries between patients with neoplastic and non-neoplastic endometrium on histopathological examination. Doppler's velocity waveforms of small endometrial blood vessels could be detected in 9% of the women with non-neoplastic endometrium and in 42% of the women with neoplastic endometrium (P<0.05). The mean+/-S.D. of the endometrial thickness was significantly higher in the women with neoplastic endometrium than that of the women with non-neoplastic endometrium (16.6+/-6.1 mm vs. 9.5+/-4.7 mm, P<0.05).

CONCLUSION

Doppler's velocity waveforms of uterine vessels coupled with transvaginal ultrasonography are not valuable enough to replace histopathological examination in the diagnosis of a neoplastic endometrial pathology. However, it may be helpful in cases in which invasive techniques are difficult to perform and in the differentiation of a certain group of patients at little risk of endometrial carcinoma.

An algorithm including results of gray-scale and power Doppler ultrasound examination to predict endometrial malignancy in women with postmenopausal bleeding

OBJECTIVE

To determine if power Doppler ultrasound examination of the endometrium can contribute to a correct diagnosis of endometrial malignancy in women with postmenopausal bleeding and endometrium > or = 5 mm.

METHODS

Eighty-three women with postmenopausal bleeding and endometrium > or = 5 mm underwent gray-scale and power Doppler ultrasound examination using predetermined, standardized settings. Suspicion of endometrial malignancy at gray-scale ultrasound examination (endometrial morphology) was noted, and the color content of the endometrium at power Doppler examination was estimated subjectively (endometrial color score). Computer analysis of the most vascularized area of the endometrium was done off-line in a standardized manner. Stepwise multivariate logistic regression analysis was carried out to determine which subjective and objective ultrasound and power Doppler variables satisfied the criteria to be included in a model to calculate the probability of endometrial malignancy.

RESULTS

Endometrial thickness, vascularity index (vascularized area/endometrial area), and use of hormone replacement therapy (HRT) satisfied the criteria to be included in the model used to calculate the 'objective probability of endometrial malignancy'. Endometrial morphology, endometrial color score and HRT use satisfied the criteria to be included in the model to calculate the 'subjective probability of malignancy'. Endometrial thickness > or = 10.5 mm had a sensitivity with regard to endometrial cancer of 0.88 and a specificity of 0.61. At a fixed sensitivity of 0.88, the specificity of the 'objective probability of malignancy' (0.81) was superior to all other ultrasound and power Doppler variables (P = 0.001-0.02). The 'objective probability of malignancy' detected more malignancies at endometrium 5-15 mm than endometrial morphology (5/7 vs. 1/7, i.e. 0.71 vs. 0.14; P = 0.125) with a similar specificity (49/57 vs. 51/57, i.e. 0.86 vs. 0.89).

CONCLUSION

Power Doppler ultrasound can contribute to a correct diagnosis of endometrial malignancy, especially if the endometrium measures 5-15 mm. The use of regression models including power Doppler results to estimate the risk of endometrial cancer deserves further development.