Benign and malignant diseases of the endometrium

Endometrial polyps: Pathogenesis, sequelae and treatment

Endometrial polyps are overgrowths of endometrial glands that typically protrude into the uterine cavity. Endometrial polyps are benign in nature and affect both reproductive age and postmenopausal women. Although endometrial polyps are relatively common and may be accompanied by abnormally heavy bleeding at menstruation. In asymptomatic women, endometrial polyps may regress spontaneously, in symptomatic women endometrial polyps can be treated safely and efficiently with hysteroscopic excision.

Magnetic Resonance Imaging Features of Endometrial Polyps: Frequency of Occurrence and Interobserver Reliability

OBJECTIVE

This study aimed to evaluate magnetic resonance imaging (MRI) features and interobserver agreement of endometrial polyps.

METHODS

After institutional review board approval, our database was searched for women older than 18 years who underwent MRI pelvis and pelvic surgical intervention from 2012 to 2016. Seventy-two patients with polyps and 75 controls composed the study cohort. Two radiologists evaluated the MRIs retrospectively for polyps. Polyp characteristics and enhancement were assessed.

RESULTS

Sensitivity and specificity of readers 1 and 2 were 59.7% and 88.0%, and 44.4 and 96.0%, respectively. There was moderate agreement for presence of polyps (κ = 0.556, P ≤ 0001), T2 fibrous core, and intratumoral cysts, with slight agreement for T2 signal and enhancement. Polyp size moderately correlated with pathology (κ = 0.465 [P = 0.025] for reader 1, κ = 0.562 [P = 0.029] for reader 2). The most common enhancement was same as myometrium.

CONCLUSION

Magnetic resonance imaging is moderately sensitive for detecting endometrial polyps, demonstrating features that are not sensitive but can be specific, with moderate interobserver agreement.

What MRI features suspect malignant pure mesenchymal uterine tumors rather than uterine leiomyoma with cystic degeneration?

Objective

To retrospectively assess conventional magnetic resonance imaging (MRI) features that differentiate malignant pure mesenchymal uterine tumors (MPMUT); endometrial stromal sarcoma (ESS) and leiomyosarcoma (LMS) from uterine leiomyoma with cystic degeneration (ULCD).

Methods

We retrospectively reviewed magnetic resonance (MR) images of 30 patients with ULCD, 18 with ESS, and 15 with LMS, to assess tumor location, margin, T2 signal intensity (SI), speckled appearance, and peripheral band using univariate and multivariate analyses.

Results

ULCD more frequently showed subserosal location (53.3%), well-defined margin (96.7%), and speckled appearance (90.0%) compared with ESS (0%, 33.3%, and 33.3%, respectively) or LMS (20.0%, 33.3%, and 60.0%, respectively). In quantitative T2 SI comparisons, the T2 SI ratio of the main solid tumor portion to gluteus maximus muscle differed significantly among the three groups, with ULCD showing a lower SI ratio (0.62) compared with ESS (2.44) and LMS (1.13). On multivariate analysis, an ill-defined margin (odds ratio [OR]=44.885; p=0.003) and high T2 SI (OR=4.396; p=0.046) were the significant MR differentiators.

Conclusion

An ill-defined tumor margin and high T2 SI ratio of the main solid tumor-to-gluteus maximus muscle were useful MRI features in the differentiation of MPMUT from ULCD.

MR appearance of normal uterine endometrium considering menstrual cycle: differentiation with benign and malignant endometrial lesions

Background The thickness and signal intensity (SI) of normal uterine endometrium on T2-weighted (T2W) imaging changes depend on the menstrual cycle phase. Cases of normal endometrium that appear similar to endometrial lesions sometimes occur, and may result in misdiagnosis. Purpose To investigate normal endometrial appearance in luteal phase (LP) compared to that in follicular phase (FP), and to differentiate these appearances with those of endometrial lesions. Material and Methods Thirty-two normal volunteers prospectively underwent magnetic resonance (MR) examinations during LP and FP. Patients with pathologically confirmed endometrial polyps ( n = 9), hyperplasia ( n = 7), and cancer ( n = 15), who underwent MR examinations, were evaluated for comparison. Endometrial appearance was categorized into the following five types on sagittal T2W imaging and compared between LP, FP, and endometrial lesions: type 1, homogeneous higher SI; type 2, homogeneous iso SI; type 3, a bright midline and a peripheral iso SI layer; type 4, a lower/iso SI central line; and type 5, heterogeneous lower/iso SI. Endometrial thickness and SI were measured and also compared. Results Endometrial lesions were more frequently categorized as type 5 than normal endometrium ( P < 0.05). Endometrial thickness in LP (mean, 1.0 cm) was significantly greater than that in FP (0.6 cm), but not significantly different from polyps (1.1 cm), hyperplasia (1.0 cm), and cancer (0.9 cm). SI in FP was significantly higher than that in LP and that of all endometrial lesions. Conclusion Differentiation between normal endometrium in LP and endometrial lesions may be difficult based on thickness alone. Heterogeneous low SI may help to differentiate normal endometrium from endometrial lesions. Performing MR imaging during FP may also help due to higher SI of normal endometrium.

Magnetic Resonance Imaging of Pelvic Masses: A Compartmental Approach

Magnetic resonance imaging (MRI) is often "one stop shop" for evaluating female pelvic masses that helps in diagnosis, staging, and restaging of these tumors. A pelvic mass can arise from any tissue present within the pelvis. Although most masses in the female pelvis arise from the reproductive organs, masses may also arise from the gastrointestinal tract, urinary system, adjacent soft tissues, peritoneum, etc. It may not always be possible to determine the site of origin or distinguish these masses based on imaging characteristics. However, familiarity with the clinicopathologic and MRI features of most common pelvic masses helps in narrowing the differential diagnosis. Diagnosis of these masses needs a holistic approach as required for any tumor including clinical history, laboratory data, and imaging characteristics. We focus on MRI characteristics of commonly encountered pelvic masses. A compartmental imaging approach is discussed in this article that helps in identifying and characterizing these masses.

Magnetic Resonance Imaging of Benign and Malignant Uterine Neoplasms

Benign and malignant uterine masses can be seen in the women. Some of these are asymptomatic and incidentally discovered, whereas others can be symptomatic. With the soft tissue contrast resolution magnetic resonance imaging can render a definitive diagnosis, which can further help streamline patient management. In this article we show magnetic resonance imaging examples of benign and malignant masses of the uterus and their treatment strategies.

MRI appearances of benign uterine disease

Benign uterine disease is a common entity affecting women of all ages. Ultrasound has historically been the predominant imaging method used in the evaluation of benign gynaecological disease, magnetic resonance imaging (MRI) being reserved for use in the staging of malignant uterine and cervical disease. MRI is now increasingly used in the diagnosis of benign uterine disease as well as a tool for problem-solving in cases of diagnostic dilemma. It allows detailed assessment of benign conditions, such as endometrial lesions, leiomyomas, and adenomyosis, and can be helpful in the stratification of patients to different treatment modalities, including surgical resection, uterine artery embolization, and medical therapies. In this article, we review the MRI findings in the common benign uterine diseases.

Accuracy of MRI with an endorectal coil for staging endometrial cancer

BACKGROUND

The very good results of magnetic resonance imaging (MRI) using an endorectal coil in staging prostate cancer at 1.5T suggested that this imaging technique might be able to be used to stage endometrial cancer, the most common tumor in postmenopausal women.

PURPOSE

To evaluate the accuracy of MRI with an endorectal surface coil for staging primary endometrial carcinoma.

MATERIAL AND METHODS

A total of 33 consecutive patients with biopsy-proven endometrial cancer underwent 1.5T MRI with an endorectal surface coil (eMRI) using sagittal and axial T2-weighted (T2w) turbo spin echo (TSE), axial T1 gradient echo 2D fat-saturated (fs), sagittal T1 gradient echo 3D with and without contrast enhancement (CE), and axial T1 TSE fs CE sequence. Evaluation of local tumor extension was based on the revised standard TNM classification for endometrial cancer. eMRI staging was compared with the histopathological results after surgery.

RESULTS

A total of 33 consecutive patients underwent eMRI for staging endometrial cancer, and 21 of these underwent primary surgery. The histological stages were as follows: T1a (n = 8), T1b (n = 10), T2b (n = 2), and T3a (n = 1). Overall staging accuracy by eMRI was 71% (15 of 21). With regard to depth of myometrial invasion, eMRI correctly diagnosed stage T1a in 75% (6/8) and stage T1b in 80% (8/10). eMRI overstaged the tumor in four patients and understaged it in two.

CONCLUSION

eMRI is highly accurate in staging myometrial invasion. However, eMRI at 1.5T does not seem to be significantly more accurate than pelvic MRI without an endorectal coil at 1.5T for staging primary endometrial cancer. eMRI for endometrial carcinoma therefore might not meet expectations compared with the results obtained using eMRI for staging prostate cancer at 1.5T.

FIGO staging system for endometrial cancer: added benefits of MR imaging

Endometrial cancer is the most commonly diagnosed gynecologic malignancy in the United States. This pathologic condition is staged with the International Federation of Gynecology and Obstetrics (FIGO) system. The FIGO staging system recently underwent significant revision, which has important implications for radiologists. Key changes incorporated into the 2009 FIGO staging system include simplification of stage I disease and removal of cervical mucosal invasion as a distinct stage. Magnetic resonance (MR) imaging is essential for the preoperative staging of endometrial cancer because it can accurately depict the depth of myometrial invasion, which is the most important morphologic prognostic factor and correlates with tumor grade, presence of lymph node metastases, and overall patient survival. Diffusion-weighted MR imaging and dynamic contrast medium-enhanced MR imaging are useful adjuncts to standard morphologic imaging and may improve overall staging accuracy.

Normal and variant pelvic anatomy on MRI

The superior tissue contrast and flexible imaging planes afforded by magnetic resonance imaging (MRI) versus competing technologies permit optimal depiction of the pelvic viscera. Targeted protocols developed for specific pelvic visceral organs highlight important anatomic features that may not be imaged by other modalities. Therefore, a solid understanding of normal and variant pelvic anatomy is crucial for appropriate interpretation of pelvic MRI studies. This article discusses the protocol strategies and relevant anatomy with commonly encountered anatomical variants in a segmented/organ-specific manner, using gender as a broad split given the substantial variance in relevant organs.

PET/CT Imaging in Gynecologic Malignancies Other than Ovarian and Cervical Cancer

Fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) is an imaging modality used for staging, assessing response to therapy, and diagnosis of recurrent cervical and ovarian cancer. The potential role of FDG-PET/CT in other gynecologic malignancies such as endometrial cancer, uterine sarcomas, vaginal, and vulvar cancer has not been fully explored.

MR Imaging of Benign Uterine Disease

MR provides excellent depiction of the female pelvic anatomy and has become the imaging modality of choice for the accurate diagnosis of numerous benign gynecologic conditions. Detection and characterization of leiomyomata and adenomyosis is performed routinely at many centers, and MR plays an important role in stratifying patients into appropriate treatment options. MR imaging is also uniquely well suited to the evaluation of gynecologic conditions that occur during pregnancy and in the postpartum period. This article describes MR protocols and the typical findings of various benign conditions of the uterine corpus and cervix, including congenital anomalies, leiomyomas, adenomyosis, and complications related to pregnancy.

Female Pelvis

MR is the diagnostic imaging modality of choice for many disorders of the female pelvis. Benign uterine disease is well-demonstrated using rapid sequences and minimal examination time,whereas evaluation of malignancy is best performed with high-resolution techniques. Wide-spread availability of ultrafast sequences has expanded MR imaging applications to include evaluation of pelvic floor relaxation and fetal anomalies. Promising developments, such as new contrast agents, MR-guided focused ultrasound,and 3 tesla imaging, suggest continued advancement of MR imaging in the care of patients who have gynecologic disease.