Current Status of Magnetic Resonance Imaging in Patients with Malignant Uterine Neoplasms: A Review

Amide proton transfer weighted combined with diffusion kurtosis imaging for predicting lymph node metastasis in cervical cancer

OBJECTIVE

To investigate the value of amide proton transfer weighted (APTw) combined with diffusion kurtosis imaging (DKI) in quantitative prediction of lymph node metastasis (LNM) in cervical carcinoma (CC).

METHODS

Data of 19 LNM(+) and 50 LNM(-) patients with CC were retrospectively analyzed. 3.0 T MRI scan was performed before the operation, including APTw and DKI. After post-processing, quantitative magnetization transfer ratio asymmetric at 3.5 ppm [MTRasym (3.5 ppm)], mean kurtosis (MK), and mean diffusivity (MD) maps were obtained. The MTRasym(3.5 ppm), MK, and MD values were respectively measured by two observers, and intra-class correlation coefficients (ICC) were used to test the consistency of the results. The independent samples t-test or Mann-Whitney U test was used to compare the differences in the values of each parameter. The ROC curve was used to analyze the predictive performance of parameters with significant differences and their combination parameter.

RESULTS

The two observers had good agreement in the measurement of each data (ICC > 0.75). The MTRasym(3.5 ppm) and MK values of the LNM(+) group(3.260 ± 0.538% and 0.531 ± 0.202) were higher than those of the LNM(-) group(2.698 ± 0.597% and 0.401 ± 0.148) (P < 0.05), while there was no significant difference in MD values between the two groups(P > 0.05). The area under the curves (AUCs) of MTRasym(3.5 ppm), MK value, and MTRasym(3.5 ppm) + MK value were 0.763, 0.716, and 0.813, respectively, when predicting LNM status of CC.

CONCLUSION

APTw and DKI can quantitatively predict LNM status of CC, which is of importance in clinical diagnosis and treatment.

A case of ovarian endometrial stromal sarcoma: Radiological and histopathological findings

Endometrial stromal sarcoma (ESS) is an uncommon uterine mesenchymal neoplasm. The primary extra-uterine location of ESS is a very rare occurrence. We present a case of a 39-year-old woman presented with severe abdominal pain, MRI showed bilateral ovarian tumors with heterogeneous intensity on T2-weighted imaging (T2WI) and T1-weighted imaging (T1WI), with restricted diffusion, including hyperintense areas on T1WI, not erased on T1-weighted fat-suppressed imaging, hypointense on T2WI, and not enhanced after contrast. This mass extended to the Douglas and invaded the uterine and the rectum serosa suggesting an underlying endometriosis. No abnormalities were suspected in the endometrium. The exploration revealed a friable mass arising from ovaries associated with nodules in the small intestine and sigmoid. The patient underwent bilateral adnexectomy and the anatomopathological study revealed a low-grade endometrial stromal sarcoma. This is one of the few reports covering the radiological features of low-grade extra-uterine ESS in the ovary which is probably secondary to degeneration of endometriosis with no evidence of primary uterine ESS.

Preliminary Application of Magnetization Transfer Imaging in the Study of Normal Uterus and Uterine Lesions

Purpose

The aim of this study is to evaluate the utility of magnetization transfer (MT) imaging in the study of normal uterus and common uterine lesions.

Methods

This prospective study enrolled 160 consecutive patients with suspected uterine lesions. MT ratio (MTR) map was obtained by pelvic MT imaging on a 3.0T MRI scanner. Patients confirmed by pathology were divided into microscopic lesion group and lesion group, according to whether the maximum diameter of the lesion was less than 5 mm. After evaluating and eliminating patients with poor image quality by a three-point Likert scale, MTR values of lesions and normal endometrium, myometrium, and cervix were independently measured on the MTR map by two radiologists. Inter-reader agreement was evaluated. MTR values were compared among different uterine lesions and normal uterine structures using the Mann–Whitney U test with Bonferroni correction. Receiver operating characteristic curve was performed. The correlations between age and MTR values were explored by Pearson correlation analyses.

Results

A total of 96 patients with 121 uterine lesions in the lesion group and 41 patients in the microscopic lesion group were measured. The MTR values among normal endometrium, myometrium, and cervix were statistical significant differences (P < 0.05). There were significant differences between endometrial cancer and normal endometrium and between cervical cancer and normal cervix (both P ≤ 0.001). Area under the curve (AUC) for diagnosing endometrial and cervical cancer were 0.73 and 0.86. Myometrial lesions had significantly higher MTR values than endometrial lesions and cervical cancer (both P < 0.001), and the AUC for differentiating myometrial lesions from them were 0.89 and 0.94. MTR values of endometrial cancer were significantly higher than those of cervical cancer (P = 0.02). There was a critical correlation between age and MTR values in endometrial cancer (r = 0.81, P = 0.04).

Conclusions

MTR values showed significant differences among normal uterine structures. It was valuable for diagnosing and differentiating uterine cancer. MTR values could differentiate myometrial lesions from endometrial or cervical lesions.

MR Imaging of uterine sarcomas: a comprehensive review with radiologic-pathologic correlation

The aim of this article is to summarize the MRI features of each sarcoma subtype and to correlate them with its pathological findings. Literature review through PubMed/Medline database to identify relevant articles on uterine sarcomas, with a special emphasis on their MRI findings and pathological features. While several, more generalistic, MRI findings of a uterine tumour should raise suspicion for malignancy (including irregular contour, intra-tumoral necrosis/hemorrhage and low ADC values), some particular features may suggest their specific histological subtype such as the gross lymphovascular invasion associated with endometrial stromal sarcomas, the "bag of worms" appearance of the low-grade endometrial stromal sarcoma and the "lattice-like" aspect of adenosarcomas which results from the mixed composition of solid and multiseptated cystic components. Knowledge of the different histological uterine sarcoma subtypes, their specific MRI features and comprehension of their pathological background allows for a more confident diagnosis and may indicate the correct histological subtype.

Utility of magnetic resonance imaging for differentiating malignant mesenchymal tumors of the uterus from T2-weighted hyperintense leiomyomas

PURPOSE

To generate a new discrimination method to distinguish between malignant mesenchymal tumors of the uterus and T2-weighted hyperintense leiomyoma based on magnetic resonance imaging findings and clinical features.

MATERIALS AND METHODS

Data from 32 tumors of 32 patients with malignant mesenchymal tumors of the uterus and from 34 tumors of 30 patients with T2-weighted hyperintense leiomyoma were analyzed. Clinical parameters, qualitative magnetic resonance imaging features, including computed diffusion-weighted imaging, and quantitative characteristics of magnetic resonance imaging of these two tumor types were compared. Predictive values for malignant mesenchymal tumors of the uterus were calculated using variant discriminant analysis.

RESULTS

The T1 bright area on qualitative assessment and mean apparent diffusion coefficient value on quantitative assessment yielded the most independent magnetic resonance imaging differentiators of malignant mesenchymal tumors of the uterus and T2-weighted hyperintense leiomyoma. The classification accuracy of the variant discriminant analysis based on three selected findings, i.e., a T1 bright area, computed diffusion-weighted imaging with a b-value of 2000s/mm² (cDWI₂₀₀₀), and T2-hypointense bands, was 84.8% (56/66), indicating high accuracy.

CONCLUSIONS

Variant discriminant analysis using the T1 bright area, cDWI₂₀₀₀, and T2-hypointense bands yielded high accuracy for differentiating between malignant mesenchymal tumors of the uterus and T2-weighted hyperintense leiomyoma.

The Value of Magnetic Resonance Imaging Histograms in the Preoperative Differential Diagnosis of Endometrial Stromal Sarcoma and Degenerative Hysteromyoma

Objective: The present study aimed to explore the application value of magnetic resonance imaging (MRI) histograms with multiple sequences in the preoperative differential diagnosis of endometrial stromal sarcoma (ESS) and degenerative hysteromyoma (DH).

Methods: The clinical and preoperative MRI data of 20 patients with pathologically confirmed ESS and 24 patients with pathologically confirmed DH were retrospectively analyzed, forming the two study groups. Mazda software was used to select the MRI layer with the largest tumor diameter in T2WI, the apparent diffusion coefficient (ADC), and enhanced T1WI (T₁CE) images. The region of interest (ROI) was outlined for gray-scale histogram analysis. Nine parameters—the mean, variance, kurtosis, skewness, 1st percentile, 10th percentile, 50th percentile, 90th percentile, and 99th percentile—were obtained for intergroup analysis, and the receiver operating curves (ROCs) were plotted to analyze the differential diagnostic efficacy for each parameter.

Results: In the T2WI histogram, the differences between the two groups in seven of the parameters (mean, skewness, 1st percentile, 10th percentile, 50th percentile, 90th percentile, and 99th percentile) were statistically significant (P < 0.05). In the ADC histogram, the differences between the two groups in three of the parameters (skewness, 10th percentile, and 50th percentile) were statistically significant (P < 0.05). In the T₁CE histogram, no significant differences were found between the two groups in any of the parameters (all P > 0.05). Of the nine parameters, the 50th percentile was found to have the best diagnostic efficacy. In the T2WI histogram, ROC curve analysis of the 50th percentile yielded the best area under the ROC curve (AUC; 0.742), sensitivity of 70%, and specificity of 83.3%. In the ADC histogram, ROC curve analysis of the 50th percentile yielded the best area under the ROC curve (AUC; 0.783), sensitivity of 81%, and specificity of 76.9%.

Conclusion: The parameters of the mean, 10th percentile and 50th percentile in the T2WI histogram have good diagnostic efficacy, providing new methods and ideas for clinical diagnosis.

CT, MRI, and FDG-PET imaging findings of low-grade extrauterine endometrial stromal sarcoma arising from the mesentery: A case report

Endometrial stromal sarcoma is a rare uterine mesenchymal neoplasm, and extrauterine endometrial stromal sarcoma is even rarer, with a limited number of case reports. In the present report, we present a case of low-grade extrauterine endometrial stromal sarcoma originating from the mesentery in a 49-year-old woman, without endometrial stromal sarcoma in the uterus or evidence of endometriosis. The tumor was diagnosed using recombination of the JAZF1 gene by fluorescence in situ hybridization. Computed tomography, magnetic resonance imaging, and 18F-fluorodeoxyglucose positron emission tomography/computed tomography showed a 13 cm, primarily polycystic, mass containing a contrast-enhancing solid component with restricted diffusion and mild 18F-fluorodeoxyglucose uptake. A large cystic component may be a characteristic feature of extrauterine endometrial stromal sarcoma, given the low pressure from the surrounding tissues.

The prominent value of apparent diffusion coefficient in assessing high-risk factors and prognosis for patients with endometrial carcinoma before treatment

BACKGROUND

To date, there are no consensus methods to evaluate the high-risk factors and prognosis for managing the personalized treatment schedule of patients with endometrial carcinoma (EC) before treatment. Apparent diffusion coefficient (ADC) is regarded as a kind of technique to assess heterogeneity of malignant tumor.

PURPOSE

To explore the role of ADC value in assessing the high-risk factors and prognosis of EC.

MATERIAL AND METHODS

A retrospective analysis was made on 185 patients with EC who underwent 1.5-T magnetic resonance imaging (MRI). Mean ADC (mADC), minimum ADC (minADC), and maximum ADC (maxADC) were measured and compared in different groups.

RESULTS

Among the 185 patients with EC, the mADC and maxADC values in those with high-risk factors (type 2, deep myometrial invasion, and lymph node metastasis) were significantly lower than in those without. According to receiver operating characteristic (ROC) curve analysis, the areas under the curve (AUC) were significant for mADC, minADC, and maxADC predicting high-risk factors. Furthermore, the AUCs were significant for mADC and maxADC predicting lymph node metastasis but were not significant for minADC. Patients with lower mADC were associated with worse overall survival and disease-free survival; the opposite was true for patients with higher mADC.

CONCLUSION

Our study showed that ADC values could be applied to assess the high-risk factors of EC before treatment and might significantly relate to the prognosis of EC. It might contribute to managing initial individualized treatment schedule and improve outcome in patients with EC.

Clinical Impact of Preoperative Magnetic Resonance Imaging in the Evaluation of Myometrial Infiltration and Lymph-Node Metastases in Stage I Endometrial Cancer

Abstract: Purpose: In the developed world, endometrial cancer is one of the most common malignant gynecological cancer types. Due to the highly available diagnostic modalities and patient education, the early detection of the tumor leads to high overall survival.

Methods: In this study we analyzed the reliability of preoperative MRI findings in the staging of early stage endometrial cancer, as well as the clinical characteristics of patients underwent radical hysterectomy and the histopathologic evaluation of their tumor, with the retrospective data of radical hysterectomies performed in our hospital between 2010 and 2019.

Results: The accuracy, sensitivity, specificity, negative- and positive predictive value of MRI regarding stage were 94.7, 63.3, 94.8, 83.8, and 83.8%, respectively. The accuracy, sensitivity, specificity, negative- and positive predictive value of MRI for the detection of the myometrial invasion were 69.8, 80.0, 60.8, 64.3, and 77.5%, respectively. The accuracy, sensitivity, specificity, negative- and positive predictive value of MRI for the detection of lymph node metastases were 78.1, 28.6, 82, 11.1, and 93.6%, respectively.

Conclusions: Based on our results, MRI is the method of choice in terms of evaluating overall staging, as well as myometrial invasion, as its specificity and negative predictive value are relatively high. However, systematic lymphadenectomy showed improved cancer-related survival and recurrence-free survival. Our studies showed that the diagnosis of lymph node metastases is difficult with MRI modality since hyperplastic and metastatic nodes cannot easily differentiate, leading to a high percentage of false-positive results. Therefore, other imaging modalities may be used for more accurate evaluation. New findings of our study were that the role of the radiologist’s expertise in the evaluation of MR imaging plays an essential role in lowering false-negative and false-positive results. Therefore, findings evaluated by a radiologist with high-level expertise in gynecological imaging can complement the clinical findings and help substantially define the needed treatment.

Diffusion-tensor imaging for differentiating uterine sarcoma from degenerative uterine fibroids

AIM

To explore the applicability of diffusion-tensor imaging (DTI) sequence quantitative parameters in differentiating uterine sarcoma (USr) from degenerative uterine fibroids (DUF).

MATERIALS AND METHODS

Fourteen cases of USr and 30 cases of DUF were analysed retrospectively. The diffusion-weighted imaging (DWI) and DTI images were analysed by two observers using Functool software on a ADW4.6 workstation. The images were post-processed to generate an apparent diffusion coefficient (ADC) map of DWI, ADC map of DTI (ADC^T map), and fractional anisotropy (FA) map. Three regions of interest (ROI) were selected from the ADC, ADC^T, and FA maps to obtain the ADC, ADC^T, and FA values. The receiver operating characteristic (ROC) curves of all parameters were used to analyse and compare the diagnostic value of USr and DUF.

RESULTS

The ADC value, ADC^T value, and FA value of USr (1.190 ± 0.262 × 10^-3mm²/s, 1.165 ± 0.270 × 10^-9mm²/s, 0.168 ± 0.063) were significantly lower compared to the values for DUF (1.525 ± 0.314 × 10^-3mm²/s, 1.650 ± 0.332 × 10^-9mm²/s, 0.254 ± 0.111; all p<0.001). The diagnostic threshold values for USr were: ADC ≤1.290 × 10^-3mm²/s, ADC^T ≤1.322 × 10^-9mm²/s and FA ≤0.192. The corresponding sensitivities and specificities were 78.6%/90%, 96.7%/92.9%, and 86.7%/85.7%, respectively. The areas under the curve (AUC) were 0.875, 0.974, and 0.831, respectively.

CONCLUSIONS

DTI quantitative parameters can be used to differentiate USr from DUF. The ADC^T value had the highest diagnostic efficacy.

Non-invasive Differentiation of Endometrial Adenocarcinoma from Benign Lesions in the Uterus by Utilization of Amide Proton Transfer-Weighted MRI

PURPOSE

To evaluate the utility of three-dimensional (3D) amide proton transfer-weighted (APTw) imaging for differentiation of endometrial adenocarcinoma and uterine benign lesions.

PROCEDURES

This prospective study enrolled 22 normal volunteers and 113 patients with suspicious uterine lesions, including endometrial adenocarcinoma, leiomyoma, and adenomyosis. Pelvic APTw MRI was performed on a 3-T MRI scanner with default APTw parameters. Two radiologists blindly evaluated uterine lesion APTw image quality by a 3-point Likert scale and independently measured APTw values on images with excellent to good image quality. Inter-reader agreement was evaluated. The Mann-Whitney U test with Bonferroni correction was used to compare the differences among different types of uterine lesions. A receiver operating characteristic analysis was performed.

RESULTS

A total of 111 lesions (33 endometrial adenocarcinoma, 26 leiomyoma, and 52 adenomyosis lesions) from 99 patients revealing a majority of good quality with excellent inter-reader agreement were included for the image quality evaluation. APTw values of endometrial adenocarcinoma were 2.9 ± 0.1 %, significantly higher than those of leiomyoma (1.9 ± 0.1 %), adenomyosis (2.2 ± 0.1 %), and normal uterine myometrium (1.9 ± 0.1 %) (all p < 0.0001). The area under the receiver operating characteristic curve for differentiating endometrial adenocarcinoma from leiomyoma, adenomyosis, and myometrium was 0.87, 0.85, and 0.91, respectively. Feasible threshold APTw values of each group were determined as 2.4 %, 2.7 %, and 2.4 % with a sensitivity of 83.3 %, 76.7 %, and 83.3 % and a specificity of 83.3 %, 81.6 %, and 86.4 %, respectively.

CONCLUSIONS

Malignant endometrial adenocarcinoma had significantly higher APTw values than leiomyoma, adenomyosis, and normal uterine myometrium. Our study adds to the growing body of validation on 3D APTw imaging and uterine lesions.

Diagnostic value of diffusion-weighted magnetic resonance imaging in discriminating between metastatic and non-metastatic pelvic lymph nodes in endometrial cancer

BACKGROUND

Researchers have recently focused on assessing the accuracy of diffusion-weighted magnetic resonance imaging (DW-MRI) in predicting pelvic lymph node metastases in gynecological malignancies.

PURPOSE

To evaluate the diagnostic value of DW-MRI in discriminating between metastatic and non-metastatic pelvic lymph nodes in endometrial cancer patients.

MATERIAL AND METHODS

This retrospective database study was conducted with 33 women aged 30-84 years with pathologically proven endometrial cancer that had been assessed by DW-MRI before their first treatment initiation at our referral hospital from March 2016 to April 2019. The diffusion technique (b = 50, 400, and 1000 mm²/s) was used in the imaging, and continuous apparent diffusion coefficient (ADC) metrics (ADC_min, ADC_max, ADC_mean, ADC_SD, and rADC) were compared between the metastatic and non-metastatic lymph nodes.

RESULTS

In total, 48 lymph nodes from 33 patients were assessed. All metastatic lymph nodes were restricted, while among the non-metastatic lymph nodes, only 19.3% were restricted. Considering pathological reports of metastatic and non-metastatic lymph nodes as the gold standard, DWI-related restricted and non-restricted features had a sensitivity of 80.6%, a specificity of 100%, and an accuracy of 87.5% to discriminate between a metastatic and non-metastatic pattern. ADC metrics of ADC_min, ADC_max, ADC_mean, ADC_SD, and rADC showed high values enabling differentiation between metastatic and non-metastatic lymph nodes. The best cut-off values were 0.7 × 10^-3, 1.2 × 10^-3, 1.01 × 10^-3, 123, and 0.78, respectively.

CONCLUSION

DW-MRI is a useful quantitative tool for differentiating between metastatic and benign lymph nodes in endometrial cancer patients.

Incidence of Gynecologic Cancers in Women after Uterine Artery Embolization

STUDY OBJECTIVE

To characterize the short-term incidence of gynecologic cancer after undergoing uterine artery embolization (UAE).

DESIGN

Retrospective cohort study.

SETTING

Commercial insurance claims database.

PATIENTS

Total of 15 393 United States women aged 18 to 64 years who underwent UAE between 2007 and 2017.

INTERVENTIONS

We used the IBM MarketScan (Armonk, NY) claims to identify adult women without previous gynecologic cancer diagnoses undergoing UAE between 2007 and 2017. Database queries identified women with any diagnostic or procedure codes related to gynecologic malignancies occurring in the first 3 years after UAE. A malignancy diagnosis was suggested by recurrent malignancy-related claims not linked exclusively to diagnostic testing (e.g., transvaginal ultrasound) and malignancy codes linked to tissue pathology claims. Incidence of malignancy diagnosis was calculated. Rates of endometrial sampling in the year before UAE were identified.

MEASUREMENTS AND MAIN RESULTS

Thirty-one women undergoing UAE had gynecologic cancer diagnoses within 3 years of the procedure (22 of 31, 71% uterine cancers; 7 of 31, 23% ovarian cancers; and 2 of 31, 6% cervical cancers). On average, cancer diagnoses were made 1.1 ± 0.9 years after UAE. One in 497 women undergoing UAE was diagnosed with a gynecologic malignancy within 3 years, with an incidence of 1.1 malignancies per 1000 person-years. Cancer incidence increased with age at the time of UAE: short-term malignancy diagnoses were made in 1 in 377 women aged 45 to 54 years, and 1 in 79 women aged 55 to 64 years. In the year before UAE, 28% (4311 of 15 362) of women without cancer, and 23% (5 of 22) of women diagnosed with uterine cancer had preprocedural endometrial sampling.

CONCLUSION

These data can inform risk/benefit counseling and shared decision-making regarding UAE and its alternatives. Short-term malignancies after UAE highlight the importance of preprocedure evaluation in symptomatic women and women with age-related risk.

Diagnostic Algorithm to Differentiate Benign Atypical Leiomyomas from Malignant Uterine Sarcomas with Diffusion-weighted MRI

Background Improving the differentiation of uterine sarcomas from atypical leiomyomas remains a clinical challenge and is needed to avoid inappropriate surgery. Purpose To develop a diagnostic algorithm including diffusion-weighted MRI criteria to differentiate malignant uterine sarcomas from benign atypical leiomyomas. Materials and Methods This case-control retrospective study identified women with an atypical uterine mass at MRI between January 2000 and April 2017, with surgery or MRI follow-up after 1 year or longer. A diagnostic algorithm including T2-weighted MRI and diffusion-weighted imaging (DWI) signal and apparent diffusion coefficient (ADC) values was developed to predict for sarcoma. The training set consisted of 51 sarcomas and 105 leiomyomas. Two external validation sets were used to evaluate interreader reproducibility (16 sarcomas; 26 leiomyomas) and impact of reader experience (29 sarcomas; 30 leiomyomas). Wilson confidence intervals (CIs) were calculated for sensitivity and specificity. Results Evaluated were 156 women (median age, 50 years; interquartile range, 44-63 years). Predictive MRI criteria for malignancy were enlarged lymph nodes or peritoneal implants, high DWI signal greater than that in endometrium, and ADC less than or equal to 0.905 × 10^-3 mm²/sec. Conversely, a global or focal area of low T2 signal intensity and a low or an intermediate DWI signal less than that in endometrium or lymph nodes allowed readers to confidently diagnose as benign a uterine mass demonstrating one or more of these signs (P < .001) in 100% cases in all three data sets. The sensitivities and specificities of the algorithm for diagnosis of malignancy were 98% (50 of 51 masses; 95% CI: 90%, 100%) and 94% (99 of 105 masses; 95% CI: 88%, 98%) in the training set; 88% (14 of 16 masses; 95% CI: 64%, 97%) and 100% (26 of 26 masses; 95% CI: 87%, 100%) in the validation set; and 83% (24 of 29 masses; 95% CI: 65%, 92%) and 97% (29 of 30 masses; 95% CI: 83%, 99%) for the less experienced reader, respectively. Conclusion A diagnostic algorithm with predictive features including lymphadenopathy, high diffusion-weighted imaging signal with reference to endometrium, and low apparent diffusion coefficient enabled differentiation of malignant sarcomas from atypical leiomyomas, and it may assist inexperienced readers. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Méndez in this issue.

Assessment of Tamoxifen-Related Endometrial Changes in Premenopausal Female Patients With Diffusion-Weighted Magnetic Resonance Imaging

PURPOSE

To evaluate tamoxifen-related endometrial changes in premenopausal female patients with diffusion-weighted magnetic resonance imaging (DWI).

METHODS

This prospective study was performed on 71 premenopausal female patients (mean age, 41 years) who were receiving tamoxifen therapy. All patients underwent magnetic resonance imaging with DWI of the pelvis and hysteroscopic-guided endometrial biopsy. The apparent diffusion coefficient (ADC) values of the endometrial plate were calculated and correlated with pathological results.

RESULTS

The mean ADCs of tamoxifen-related benign endometrial lesions (1.35 ± 0.19 and 1.32 ± 0.13 × 10 mm/s) were significantly higher (P = 0.001) than those of normal endometrial plate (0.95 ± 0.11 and 0.93 ± 0.11 × 10 mm/s) by both reviewers, respectively. The cutoff ADC values used to differentiate tamoxifen-related benign endometrial lesions from normal endometrium were 1.07 and 1.02 × 10 mm/s with areas under the curve of 0.94 and 0.93 and accuracy of 94.4 and 95.8 by both reviewers, respectively. The mean ADC values of endometrial polyp (EP) (1.44 ± 0.19 and 1.42 ± 0.22 × 10 mm/s) were significantly higher (P = 0.001) than those of endometrial hyperplasia (EH) (1.25 ± 0.19 and 1.23 ± 0.19 × 10 mm/s) by both reviewers, respectively. The cutoff ADC values used to differentiate EP from EH were 1.38 × 10 and 1.36 × 10 mm/s with areas under the curve of 0.81 and 0.77 and accuracy of 80% and 70% by both reviewers, respectively. There was an insignificant difference in ADC value between typical and atypical EH. The ADC values of endometrial cancer (0.80 and 0.78 × 10 mm/s) were lower than those of tamoxifen-related benign endometrial lesions. The final diagnosis was normal endometrium (n = 36), benign endometrial lesions either EH (n = 17), or EP (n = 16), and endometrial cancer in only 2 patients.

CONCLUSIONS

We concluded that DWI helps in detection and characterization of different tamoxifen-related endometrial changes in the premenopausal female patients.

SMARCA4-deficient uterine sarcoma: A case report and a concise review

Background

SMARCA4-deficient uterine sarcoma (SDUS) is a newly discovered undifferentiated uterine mesenchymal malignancy which has loss of expression of SMARCA4.

Case

A 46-year-old woman presented with heavy irregular vaginal bleeding over the previous 5 months. Computed tomography and magnetic resonance imaging showed a large pelvic mass centered within the uterus, suspicious of malignancy with regional metastatic lymphadenopathy. Biopsy confirmed SDUS and patient underwent chemotherapy. Her symptoms improved 3 months after treatment.

Conclusion

An extremely rare case of this newly described entity is reported. Recognizing the characteristic imaging and pathology findings of SDUS is essential for an accurate diagnosis, which may affect patient survival.

Differential Diagnosis of Uterine Leiomyoma and Uterine Sarcoma using Magnetic Resonance Images: A Literature Review

MRI plays an essential role in patients before treatment for uterine mesenchymal malignancies. Although MRI includes methods such as diffusion-weighted imaging and dynamic contrast-enhanced MRI, the differentiation between uterine myoma and sarcoma always becomes problematic. The present paper discusses important findings to ensure that sarcomas are not overlooked in magnetic resonance (MR) images, and we describe the update in the differentiation between uterine leiomyoma and sarcoma with recent reports.