The aim in the diagnosis of abnormal uterine bleeding (AUB) is to identify the bleeding cause, which can be classified by the PALM-COEIN ( P olyp, A denomyosis, L eiomyoma, M alignancy (and hyperplasia), C oagulopathy, O vulatory disorders, E ndometrial, I atrogenic and N ot otherwise classified) classification system.
In a gynecologic setting, the first step is most often to identify structural abnormalities (PALM causes). Common diagnostic options for the identification of the PALM include ultrasonography, endometrial sampling, and hysteroscopy. These options alone or in combination are sufficient for the diagnosis of most women with AUB. Contrast sonography with saline or gel infusion, three-dimensional ultrasonography, and magnetic resonance imaging may be included.
Aim
The aim of this article is to describe how a simple structured transvaginal ultrasound can be performed and implemented in the common gynecologic practice to simplify the diagnosis of AUB and determine when additional invasive investigations are required.
Structured transvaginal ultrasound for the identification of the most common endometrial and myometrial abnormalities and the most common ultrasound features are described. Moreover, situations where magnetic resonance imaging may be included are described.
This article proposes a diagnostic setup in premenopausal women for the classification of AUB according to the PALM-COEIN system. Moreover, a future diagnostic setup for fast-track identification of endometrial cancer in postmenopausal women based on a structured evaluation of the endometrium is described.
Highlights
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Structured evaluation of the endometrium and myometrium is fundamental.
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Ultrasound algorithm for the diagnosis of premenopausal AUB is presented.
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Presence of each image feature of adenomyosis should be evaluated for diagnosis.
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Mapping of leiomyomas is required before minimally invasive treatment.
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REC scoring may most accurately identify malignancy in postmenopausal bleeding.
Introduction
The main diagnostic categories in abnormal uterine bleeding (AUB) are characterized by the PALM-COEIN system , and the diagnostic setup should aim to define AUB in these categories:
PALM-COEIN ( P olyp, A denomyosis, L eiomyoma, M alignancy (and hyperplasia), C oagulopathy, O vulatory disorders, E ndometrial, I atrogenic and N ot otherwise classified) classification system.
AUB is defined as bleeding from the uterine corpus that is abnormal in regularity, volume, frequency, or duration . In women with AUB, a history is taken including the type of bleeding pattern (frequency, regularity, duration, and volume). Moreover, it is important to determine whether the bleeding problem is acute (may require immediate intervention to prevent further blood loss) or chronic. AUB may affect the woman’s daily activity or cause worry about undetected serious disease.
Before a diagnosis of “COEIN” causes is made, causes related to uterine structural abnormalities, i.e., “PALM,” are excluded. An exception is the early reproductive period when PALM causes are extremely rare. A possible coagulopathy may be identified in 90% of the women using a structured history .
Ovulatory disorders are characterized by infrequent or irregular bleeding, which is common in the early and late reproductive period. Other common causes are polycystic ovarian syndrome, hyperprolactinemia, hypothyroidism, and contributing factors such as obesity, anorexia, weight loss, mental stress, and extreme exercise.
In the diagnosis of AUB, a structured history, general examination, and exclusion of cervical and other causes of AUB have to be performed before imaging, as described in other chapters in this volume.
Transvaginal ultrasound (TVS) has become the first-step diagnostic tool for the identification of the “PALM” causes of AUB. TVS is often available in the gynecologic office and is increasingly often integrated in the general gynecologic examination of women with AUB. The advantage is a fast and immediate diagnosis of the most common structural abnormalities in the uterus and ovaries. Doppler, contrast hysterosonography (COH) with saline (saline infusion sonography; SIS) or gel infusion (gel infusion sonography; GIS), and three-dimensional TVS (3D-TVS) can be included. Alone or in combination with endometrial sampling (ES) and hysteroscopy, these options are sufficient for the diagnosis of women with AUB.
However, TVS, particularly COH, is an observer-dependent technique, and training is required to reach a high diagnostic efficiency. Moreover, AUB is a common condition, and referral to image centers or specialists in sonography is expensive, and additional appointments for imaging are inconvenient for women. Most abnormalities can be diagnosed by a gynecologist after training in ultrasonography when a systematic approach is obtained in performing sonography.
This article describes how a systematic TVS can be used in the office for the diagnosis of AUB and when should 3D-TVS, COH, magnetic resonance imaging (MRI), ES, and hysteroscopy be included.
General Background
The diagnostic options are different in postmenopausal and premenopausal women.
In postmenopausal women, uterine bleeding is a cardinal symptom of endometrial malignancy, which may be present in 10% of postmenopausal women with bleeding . The main issue is to exclude hyperplasia and malignancy. Moreover, these women should have a fast-track diagnostic setup. The survival in case of endometrial cancer is very high if detected at an early stage of disease, and it is therefore important to promote early identification of endometrial cancer.
Premenopausal women visit their doctors in case of AUB because a change in bleeding pattern worries them and/or because AUB interferes with their daily life (quality of life), and they wants some kind of treatment.
Treatment options depend on the diagnosis, severity of symptoms, fertility desire, other symptoms, comorbidities, and individual preferences. In the presence of “PALM” causes, the “stage” or extent of the disease (size of polyp, mapping of adenomyosis and leiomyomas, and FIGO stage of Malignancy) has to be determined to offer the appropriate strategy for minimal invasive treatment for the individual patient.
Hysteroscopy should be performed in the absence of sufficient imaging of endometrial pathology by TVS or COH. MRI may be included when ultrasound imaging is insufficient to make a diagnosis, to perform sufficient mapping of myometrial or adnexal pathology, to select the most optimal treatment options, or when additional extra-pelvic disease is suspected. MRI should be regarded as a complementary investigation to TVS.
Transvaginal ultrasound
Evaluation of AUB should most optimally be performed as a one-step procedure. TVS, COH with SIS or GIS, ES, and hysteroscopy are diagnostic methods that should be combined and perceived as complementary methods used for optimal evaluation of the uterine wall and uterine cavity. COH and ES are most optimally integrated in the one-stop office setup. Additionally, hysteroscopy with the use of small-caliber hysteroscopes is increasingly used, and this has the advantage, opposed to COH alone, that simultaneous removal of small polyps and leiomyomas in the uterine cavity can be performed.
A structured image evaluation by TVS includes the description of (A) the endometrial cavity, (B) myometrium, and (C) ovaries, which is the most important first step to diagnose structural abnormalities (PALM causes) in the uterus as a cause of AUB.
At first, the endometrial cavity evaluation is described:
Table 1 presents an outline of the elements for a structured evaluation and the common terms for the description of the endometrium and abnormalities in the endometrial cavity by TVS with the inclusion of Doppler and COH (measurements, outline, and morphology and pattern of lesions).
| Endometrium | Elements |
|---|---|
| Endometrial thickness | “double endometrial thickness in sagittal plane” |
| Morphology | uniform (includes the three-layer pattern, the homogeneous hyper-, hypo-, and isoechogenic endometrium) not uniform |
| Outline | linear/nonlinear; irregular/not defined |
| Contrast hysterosonography | |
| Endometrial outline | Regular (smooth) or irregular “cauliflower like” or “spiky” |
| Lesion: Size, echogenicity | 3 perpendicular diameters, “uniform” (homogenic) or “nonuniform” (heterogenic), which includes cystic lesions |
| Doppler: color score | Color score:(1) no color flow, (2) with minimal color, (3) with moderate color, and (4) with abundant color |
| Vessel pattern | Vessels may be single, double, or multiple; of focal or multifocal origin; or with circular flow. Caliber of vessels: large or small Branching of vessels: orderly or disorderly/chaotic |
General Background
The diagnostic options are different in postmenopausal and premenopausal women.
In postmenopausal women, uterine bleeding is a cardinal symptom of endometrial malignancy, which may be present in 10% of postmenopausal women with bleeding . The main issue is to exclude hyperplasia and malignancy. Moreover, these women should have a fast-track diagnostic setup. The survival in case of endometrial cancer is very high if detected at an early stage of disease, and it is therefore important to promote early identification of endometrial cancer.
Premenopausal women visit their doctors in case of AUB because a change in bleeding pattern worries them and/or because AUB interferes with their daily life (quality of life), and they wants some kind of treatment.
Treatment options depend on the diagnosis, severity of symptoms, fertility desire, other symptoms, comorbidities, and individual preferences. In the presence of “PALM” causes, the “stage” or extent of the disease (size of polyp, mapping of adenomyosis and leiomyomas, and FIGO stage of Malignancy) has to be determined to offer the appropriate strategy for minimal invasive treatment for the individual patient.
Hysteroscopy should be performed in the absence of sufficient imaging of endometrial pathology by TVS or COH. MRI may be included when ultrasound imaging is insufficient to make a diagnosis, to perform sufficient mapping of myometrial or adnexal pathology, to select the most optimal treatment options, or when additional extra-pelvic disease is suspected. MRI should be regarded as a complementary investigation to TVS.
Transvaginal ultrasound
Evaluation of AUB should most optimally be performed as a one-step procedure. TVS, COH with SIS or GIS, ES, and hysteroscopy are diagnostic methods that should be combined and perceived as complementary methods used for optimal evaluation of the uterine wall and uterine cavity. COH and ES are most optimally integrated in the one-stop office setup. Additionally, hysteroscopy with the use of small-caliber hysteroscopes is increasingly used, and this has the advantage, opposed to COH alone, that simultaneous removal of small polyps and leiomyomas in the uterine cavity can be performed.
A structured image evaluation by TVS includes the description of (A) the endometrial cavity, (B) myometrium, and (C) ovaries, which is the most important first step to diagnose structural abnormalities (PALM causes) in the uterus as a cause of AUB.
At first, the endometrial cavity evaluation is described:
Table 1 presents an outline of the elements for a structured evaluation and the common terms for the description of the endometrium and abnormalities in the endometrial cavity by TVS with the inclusion of Doppler and COH (measurements, outline, and morphology and pattern of lesions).
| Endometrium | Elements |
|---|---|
| Endometrial thickness | “double endometrial thickness in sagittal plane” |
| Morphology | uniform (includes the three-layer pattern, the homogeneous hyper-, hypo-, and isoechogenic endometrium) not uniform |
| Outline | linear/nonlinear; irregular/not defined |
| Contrast hysterosonography | |
| Endometrial outline | Regular (smooth) or irregular “cauliflower like” or “spiky” |
| Lesion: Size, echogenicity | 3 perpendicular diameters, “uniform” (homogenic) or “nonuniform” (heterogenic), which includes cystic lesions |
| Doppler: color score | Color score:(1) no color flow, (2) with minimal color, (3) with moderate color, and (4) with abundant color |
| Vessel pattern | Vessels may be single, double, or multiple; of focal or multifocal origin; or with circular flow. Caliber of vessels: large or small Branching of vessels: orderly or disorderly/chaotic |
Additional methods for the evaluation of the endometrial cavity
Contrast hysterosonography
Contrast hysterosonography (COH), also known as sonohysterography, is a diagnostic technique consisting of ultrasound imaging with a concurrent intrauterine infusion of a sonographic contrast solution such as saline or gel. The contrast infusion is performed by using intrauterine inseminations catheters , silicon uterine catheters with balloons , baby-feeding tubes , and various other forms of catheters. Several catheters have been compared, and some were more tolerable than others; however, it was not possible to find any clear advantage of any catheter . Chorionic villus biopsy catheters or spinal needles may be used in women with cervical stenosis. COH has a higher diagnostic efficiency than TVS for the diagnosis of polyps and myomas in the endometrial cavity . One in every five polyps is missed by TVS; although TVS may identify most leiomyomas, COH may identify the relation of myomas to the uterine cavity better than TVS (type 0–2) and thereby help to determine whether hysteroscopic surgery is optimal . COH has a lower number of false positives when examinations are performed in the follicular phase .
COH fails in approximately 7% of women, most often in postmenopausal women and most commonly caused by cervical stenosis . In approximately 8–10% of the procedures, SIS may be insufficient. This is typically due to the backflow of saline and inadequate distention or filling of the endometrial cavity .
The use of gel instead of saline decreases the backflow and produces a more stable filling of the endometrial cavity . Gel with local anesthesia has been tested ; however, it does not seem to reduce the pain or discomfort associated with COH. The discomfort is usually moderate when a baby-feeding tube without a balloon is used. A stable filling of the uterine cavity is particularly important for 3D-COH. 3D-COH can be added to COH and may marginally improve the efficiency for the diagnosis of polyps and leiomyomas in the endometrial cavity but rarely adds important information that will change the treatment of patients in daily practice .
Endometrial sampling
Histology of the endometrium is the golden standard for the diagnosis of endometrial pathology as hyperplasia or malignancy. Samples can be obtained by suction aspiration, curettage, or hysteroscopic biopsies. ES is not efficient for the diagnosis of endometrial polyps, adenomyosis, or leiomyomas .
In premenopausal women with AUB, malignancy is rare. ES is obtained on the basis of personal risk factors for hyperplasia and cancer. Evidence-based risk factors are used; however, there is no evidence or consensus on the exact level of risk and choice of different risk factors required to perform ES. The risk factors suggested in the algorithm are based on the Danish guidelines .
In postmenopausal women, ES has a high specificity but has a disadvantage of a low sensitivity and a high frequency of insufficient or failed samples . Other diagnostic methods are recommended as outlined in postmenopausal diagnostic setup.
Malignancy and hyperplasia are rare in premenopausal women, and ES is a sufficient diagnostic technique to exclude malignancy in premenopausal women without localized endometrial changes in the endometrial cavity .
Hysteroscopy
Hysteroscopy is regarded as the golden standard for the evaluation of the endometrial cavity. COH and hysteroscopy have the same high efficiency for exclusion of abnormalities in the endometrial cavity . However, COH and hysteroscopy should not be regarded as alternative options but rather as complimentary investigations in women with AUB. Hysteroscopy may be unnecessary when a normal endometrial cavity has been visualized using the simpler COH technique. When findings are equivocal by COH, hysteroscopy may be included. Hysteroscopy may also be beneficial in diagnosing patients with more than one abnormality at the same time . Pathology in the myometrium may only have a slight or no effect on the endometrium and is usually not seen by hysteroscopy but may be demonstrated by concomitant TVS/COH. Thus, the efficiency of hysteroscopy is often improved using ultrasonography immediately before or during hysteroscopy. Moreover, COH can be used for the selection of type of hysteroscopy. In the presence of small intrauterine polyps or localized pathology, small–caliber hysteroscopes may be selected and used in an office setting without anesthesia and enable the immediate removal of these small abnormalities. In the presence of large pathologies (e.g., larger type 2 myomas), operative hysteroscopes and the right surgeon should be selected.
Like by ultrasound, a structured evaluation of the total endometrial cavity and all pathologies (surface, necrosis, and vessels) by hysteroscopy is important .
PALM diagnosis
Benign endometrial polyps
Endometrial polyps are diagnosed using histopathology. Endometrial polyps consist of endometrial glands, stroma, and blood vessels . They are composed of a dense fibrous tissue (stroma), covered by surface epithelium endometrium. The stroma has large thick-walled vascular channels and glandular spaces of varying shapes and sizes . Endometrial polyps are localized endometrial intrauterine overgrowths that may be single or multiple, measuring from a few millimeters to few centimeters, and may be sessile (when the diameter of the base of the polyp is larger than or the same as the largest diameter of the polyp) or pedunculated (when the diameter of the base of the polyp is smaller than the largest diameter of the polyp) .
Endometrial polyps are often observed as homogenic or inhomogenic hyperechoic masses in the endometrium with regular contours or as nonspecific endometrial thickenings or focal masses within the endometrial cavity . Regular cystic areas may be observed , and the “bright edge” sign may be observed at the border of the polyps. The bright edge is defined as a sharp and smooth echogenic line positioned at the transitional zone between the myometrium and centrally undefined endometrial echoes . Polyps are often not distinctive from the endometrium. Doppler findings of a relatively small single or double feeding vessel with regular branching are characteristic findings .
Most endometrial polyps may be identified using TVS. The use of a cut-off value for endometrial thickness for the diagnosis of polyps or hyperplasia may not be efficient in premenopausal women as opposed to postmenopausal women .
In a review including pre- and postmenopausal women, TVS has reported to have a median sensitivity of 91% (range 19–100%) and median specificity of 90% (range 53–100%) for the diagnosis of polyps. SIS had higher efficiency with a median sensitivity of 95% (range 58–100%) and median specificity of 92% (range 35–100%) . In another review, only including premenopausal women, TVS had a sensitivity of 80% (range 31–94%) , whereas SIS had a sensitivity of 93% and specificity of 96% for the diagnosis of polyps.
In postmenopausal women are imaging features like in premenopausal women a homogenic or inhomogenic often hyperechoic mass in the endometrium, often not distinctive from the endometrium. Polyps are often cystic in postmenopausal women.
Myometrial abnormalities (leiomyomas and adenomyosis)
An evaluation of the uterus starts with an overall description of the uterus, asymmetry of uterine walls, global enlargement, and contour. The size of the uterus may be measured (length, anteroposterior diameter, and transverse diameter). Well-defined or ill-defined uterine lesions are systematically described, as given in Table 2 .
| Overall uterus | Symmetrical, asymmetrical, globally enlarged | |
| Myometrial lesions | Well-defined/ill-defined, absent | |
| Echogenicity | Uniform: nonuniform: | hypo-, iso-, hyperechogenic; mixed echogenicity |
| Rim | Hypo- or hyperechogenic, ill-defined, or not defined | |
| Shape | Round/nonround: oval, lobulated, irregular | |
| Shadowing | Edge Internal Fan-shaped | Not present, slight, moderate, strong |
| Cyst | number, size Cyst fluid | Outline: Regular, irregular, ill-defined anechogenic, low level, ground glass, mixed echogenicity |
| Hyperechoic islands | Present/absent | |
| Subendometrial echogenic lines and buds | Present/absent | |
| Amount of color (in a lesion) | Color score (subjective impression of percentage of lesion and hue) | No color (1); minimal color (2); moderate color (3); and abundant color (4) |
| Vessel location | Circumferential, intralesional; uniform, nonuniform |
Leiomyomas
A systematic evaluation of myometrial mass includes evaluation of outline, echo structure, and vascularity. Typical ultrasound features of myomas in the myometrium are well-defined, round lesion. Shadowing is often present at the edge of myomas (edge shadows) or internally (fan-shaped shadowing).
The echogenicity is most often low to isoechogenic, but some internal high echogenicity may be present . In color or power Doppler imaging, a typical circumferential flow around the lesion is often visible.
Diagnostic efforts may depend on the need for treatment. Several women with leiomyomas are asymptomatic or show only a few symptoms. Women with AUB and leiomyomas may have anovulatory bleeding and concomitant asymptomatic leiomyomas or bleeding caused by leiomyomas, or the cause is both anovulatory and leiomyomas, particularly in the perimenopausal period. Decision regarding treatment may depend on the severity of symptoms, other myoma-related symptoms (for example, bulk symptoms, pain, or urinary symptoms), woman’s desire for future pregnancy, or a general preference for minimally invasive treatment options. Mapping of myomas is required to decide on minimally invasive treatment options.
Myometrial lesions are described as outlined in Table 3 . The number of leiomyomas with diameter larger than 1–1.5 cm should be counted, measured, and mapped according to location and site (0-8).
| Myomas | ||
|---|---|---|
| Numbers | N | n |
| Location | anterior, posterior, fundal, right lateral, left lateral, or global | |
| Size | The three largest perpendicular diameters (a1, a2, a3), and/or Volume (V) in cm 3 = a1 cm × a2 cm × a3 cm × 0.523 | |
| Site | Site (for well-defined lesions): FIGO classification 1–7: | FIGO: |
| Submucous | Endocavitary myoma portion: 100%, ≥50%, or <50%. | Type 0, Type1, Type 2 |
| Intramural | Contacts endometrium, does not contact endometrium | Type 3, Type 4 |
| Subserosal | ≥50% intramural, <50% intramural, pedunculated | Type 5, Type 6, Type 7 |
| Other (specify, e.g., cervical, parasitic) | Type 8 | |
| Hybrid | Impact on both endometrium and serosa | Type: 2–5 |
| Lesion-free margin | The minimal distance between the serosal surface and the outer portion of the lesion; the minimal distance between the endometrium and the inner portion of the lesion | Outer/Inner |
| Adenomyosis | ||
| Extent of ill-defined lesions | Localized (<50% of total uterine volume involved) or diffuse (≥50% of total uterine volume involved) | |
| Penetration of ill-defined lesions | Ratio of maximum diameter of lesion perpendicular to endometrium in relation to maximum wall thickness perpendicular to endometrium |
COH is required to determine the effect of leiomyomas on the endometrial cavity. TVS is an accurate technique to measure and map when there are 1–4 leiomyomas . Measurements of the volume of leiomyoma are normally performed using the caliper method by TVS. Three perpendicular diameters of the leiomyoma are used to mathematically calculate the volume using the ellipse formula.
The measurement error is estimated to be approximately 20% of the diameter for leiomyomas with a diameter of 5 cm . This substantial measurement error is important to realize when the size of leiomyomas is monitored during observation or treated using methods such as ulipristal acetate and embolization.
Vascularity of leiomyomas may often be spontaneously impaired and induce their degeneration. Initial edema and hemorrhage are followed by various degrees of collagen deposition and cystic change, which gives rise to an atypical imaging feature.
This degeneration often leads to a heterogenic echotexture of the leiomyomas, where the structure of heterogenicity is based on the type of degeneration. Myomas with atypical imaging features are called atypical myomas.
Leiomyosarcomas commonly undergo degeneration and display imaging features such as atypical myomas, which make differentiation by imaging difficult.
In postmenopausal women, leiomyomas are often seen as small distinct hypoechoic areas with a hyperechoic rim and limited vascularity. However, ordinary myomas may also have high vascularity, heterogeneity, and atypical features like in premenopausal women. Hormone replacement in menopause can initiate growth, although significant growth of a leiomyoma in postmenopausal women may indicate malignancy.
Magnetic resonance imaging
In the presence of multiple (more than four) myomas, MRI is more accurate than TVS . MRI may enable the mapping of more myomas because acoustic shadowing is absent when using this technique. Additionally, MRI enables the evaluation of myomas in three perpendicular planes and those situated high in the pelvis .
Moreover, the accuracy in the measurement of size may be improved using MRI when a stereologic technique and not the caliber method is used .
MRI is the standard image modality used before minimally invasive treatment options of myomas such as magnetic resonance-guided high-intensity focused ultrasound and uterine artery embolization. MRI is the method used to evaluate the perfusion of myomas, which is important before and after these treatment options. Tissue perfusion in myomas is evaluated by the uniform or nonuniform early enhancement after contrast MRI and can be described to range from 0% to 100%. Leiomyomas without preoperative perfusion may not respond to treatment, and postoperative interruption of perfusion is important for sufficient efficiency of the treatment . In diffusion-weighted MRI, coefficients for diffusion may be calculated, and areas with restricted perfusion in relation to surrounding tissue may be identified.
Three-dimensional-transvaginal ultrasound:
A 3D volume of the uterus or ovary is very easily obtained and can be stored and manipulated in all planes and evaluated later and shared in conferences. The coronal view can be demonstrated using 3D-TVS, and it is very important for the evaluation of uterine anomalies, particularly when COH is included . 3D-TVS provides important information on the junctional zone (JZ), which is important in adenomyosis (see adenomyosis section). 3D-TVS may be advantageous in the evaluation of a few myomas ; however, in the presence of multiple myomas, shadowing may interfere with imaging, and 3D-TVS is impractical .
Leiomyosarcoma
No imaging technique can diagnose a leiomyosarcoma with certainty , and some leiomyosarcomas are not diagnosed until after surgery . Approximately one-fourth to two-thirds of the leiomyosarcomas can be diagnosed by ES and another one-fourth of the sarcomas have clear preoperative abnormal imaging features; therefore, they are treated correctly according to a suspected malignant condition .
The diagnosis of leiomyosarcomas may be improved by an increased awareness of typical signs of leiomyosarcomas ( Table 4 ). The imaging features that raise suspicion of leiomyosarcomas are summarized in Table 4 .
| Leiomyosarcoma | Leiomyomas | |
|---|---|---|
| Age | >45 years | <45 years |
| Leiomyoma | Single | Multiple |
| Size | >8 cm diameter | <8 cm diameter |
| Calcification | Lack of calcification | Calcification |
| Echo structure | Heterogenic, cystic degeneration, irregular texture, necrosis (areas with fluent low-echoic hemorrhage) | Homogeneous, edge shadows |
| Vascularity | Highly peripheral and central vascularity | Moderate peripheral, seldom marked central vascularity |
| Border | Might be irregular | Regular, edge shadows |
| Endometrial sample | Might be malignant | Not malignant |
| Serum markers | Increased LDH, neutrophil-to-lymphocyte ratio > 2.1 | No increase in LDH, neutrophil-to-lymphocyte ratio > 2.1 |
| Magnetic resonance imaging | Heterogenic, cystic, irregular borders, early enhancement, diffusion, high signal intensity, decreased diffusion coefficients | Homogenic, clear borders, late enhancement, diffusion late, no decrease in diffusion coefficients |
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