Myometrial Invasion In Endometrial Cancer Research Articles

Enhancing Preoperative Assessment of Endometrial Cancer: The Role of Diffusion-Weighted Magnetic Resonance Imaging in Evaluating Myometrial Invasion.

Endometrial cancer (EC) is the most common gynecological malignancy. Accurate preoperative staging is essential for guiding treatment. The depth of myometrial invasion is a key prognostic factor. This prospective study aimed to evaluate the added benefit of diffusion-weighted imaging (DWI) compared to T2-weighted imaging (T2WI) and dynamic contrast-enhanced MRI (DCE-MRI) for the preoperative assessment of myometrial invasion in EC. The aim of this prospective study was to evaluate the added benefit of DWI in the preoperative assessment of myometrial invasion in EC, in comparison with T2WI and DCE-MRI. The objectives were to assess the imaging characteristics of endometrial carcinoma on T2WI, DCE, and DW MR, to assess the depth of myometrial invasion and overall stage in EC patients, to compare the diagnostic performance of DCE-MRI with that of DW-MRI combined with T2WI, to describe how MR imaging findings can be combined with tumor histologic features and grading to guide treatment planning, and to evaluate the pitfalls and limitations of DCE and DW MR in the assessment of EC. Thirty-one patients with histologically confirmed EC underwent preoperative pelvic MRI on a 1.5T scanner. T2WI, DWI (b-values 0, 1000 s/mm2), and DCE-MRI were performed. Two radiologists independently assessed myometrial invasion on T2WI, T2WI + DWI, and T2WI + DCE-MRI. Histopathology after hysterectomy was the reference standard. Diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each MRI protocol, with separate analyses for superficial (<50%) and deep (≥50%) myometrial invasions. The accuracy for assessing superficial invasion was 61.3% for T2WI, 87.1% for T2WI + DWI, and 87.1% for T2WI + DCE-MRI. For deep invasion, accuracy was 64.5% for T2WI, 90.3% for T2WI + DWI, and 90.3% for T2WI + DCE-MRI. Sensitivity, specificity, PPV, and NPV for T2WI + DWI and T2WI + DCE-MRI were high and comparable (88.9-91.7%) for both superficial and deep invasions. T2WI had markedly lower sensitivity and specificity. The differences between T2WI and the functional MRI protocols were statistically significant (p < 0.01). DWI and DCE-MRI significantly improve the diagnostic performance of MRI for the preoperative assessment of myometrial invasion depth in EC compared to T2WI alone. DWI + T2WI and DCE-MRI + T2WI demonstrate comparable high accuracy. DWI may be preferable since it is faster and avoids contrast administration.

Multiparametric magnetic resonance imaging-based assessment of the effect of adenomyosis on determining the depth of myometrial invasion in endometrial cancer.

Accurate preoperative diagnosis of endometrial cancer (EC) with deep myometrial invasion (DMI) is critical to deciding whether to perform lymphadenectomy. However, the presence of adenomyosis makes distinguishing DMI from superficial myometrial invasion (SMI) on magnetic resonance imaging (MRI) challenging. We aimed to evaluate the accuracy of multiparametric MRI (mpMRI) in diagnosing DMI in EC coexisting with adenomyosis (EC-A) compared with EC without coexisting adenomyosis and to evaluate the effect of different adenomyosis subtypes on myometrial invasion (MI) depth in EC. Patients with histologically confirmed International Federation of Gynecology and Obstetrics (FIGO) stage I EC who underwent preoperative MRI were consecutively included in this 2-center retrospective study. Institution 1 was searched from January 2017 to November 2022 and institution 2 was searched from June 2017 to March 2021. Patients were divided into 2 groups: group A, patients with EC-A; group B, EC patients without coexisting adenomyosis, matched 1:2 according to age ±5 years and tumor grade. A senior radiologist assessed the MRI adenomyosis classification in group A. Then, 2 radiologists (R1/R2) independently interpreted T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), T1-weighted contrast-enhanced (T1CE), and a combination of all images (mpMRI) respectively, and then assessed MI depth. Accuracy, sensitivity, specificity, and the areas under the receiver operating curve (AUC) were calculated. The chi-square test was used to compare the accuracy of diagnosing DMI. Interobserver agreement was evaluated using the Kappa test. A total of 70 cases in group A and 140 cases in group B were included. The accuracy, sensitivity, and specificity of consensus were 94.3% [95% confidence interval (CI): 88.9-99.7%] vs. 92.1% (95% CI: 87.7-96.6%), 60.0% (95% CI: 17-92.7%) vs. 86.7% (95% CI: 68.4-95.6%), and 96.9% (95% CI: 88.4-95.5%) vs. 93.6% (95% CI: 86.8-97.2%) (group A vs. group B, respectively). There was no significant difference in the diagnostic accuracy of DMI on each sequence between the groups (Reviewer 1/Reviewer 2): PT2WI=0.14/0.17, PDWI=0.50/0.33, PT1CE=0.90/0.18, PmpMRI=0.50/0.37. The AUC for T2WI, DWI, T1CE, and mpMRI (Reviewer 1/Reviewer 2), respectively, were 0.54 (95% CI: 0.42-0.66)/0.78 (95% CI: 0.67-0.87), 0.63 (95% CI: 0.50-0.74)/0.77 (95% CI: 0.65-0.86), 0.69 (95% CI: 0.57-0.80)/0.79 (95% CI: 0.68-0.88), and 0.91 (95% CI: 0.82-0.97)/0.89 (95% CI: 0.79-0.95) (group A) and 0.83 (95% CI: 0.76-0.89)/0.85 (95% CI: 0.78-0.90), 0.83 (95% CI: 0.76-0.89)/0.86 (95% CI: 0.79-0.91), 0.88 (95% CI: 0.82-0.93)/0.86 (95% CI: 0.80-0.92), and 0.91 (95% CI: 0.85-0.95)/0.87 (95% CI: 0.80-0.92) (group B). Interobserver agreement was highest with mpMRI [κ=0.387/0.695 (case/control)]. The consensus results of MRI categorization of adenomyosis revealed no significant difference in the accuracy of diagnosing DMI by adenomyosis subtype (Pspatial relationship>0.99, Paffected area=0.52, Paffected pattern=0.58, Paffected size>0.99). The presence of adenomyosis or adenomyosis subtype had no significant effect on the interpretation of the depth of MI. T1CE can increase the contrast between adenomyosis and cancer foci; therefore, the information provided by T1CE should be valued.

Can MRI Accurately Diagnose and Stage Endometrial Adenocarcinoma?

Background and Objectives: Endometrial carcinoma is one of the most common gynecological cancers, and benign lesions such as endometrial hyperplasia, polyps, adenomyosis and leiomyomas should be included in the differential diagnosis. Magnetic resonance imaging has an important role in evaluating endometrial cancer and assessing the depth of myometrial invasion, and it closely correlates with the prognosis of the patient. The purpose of this study is to evaluate the MRI semiology of the endometrial carcinomas that mimic benign lesions, the main factors that may affect the correct diagnosis and the feasibility of magnetic resonance imaging to evaluate the depth of the myometrial invasion of endometrial cancer. Materials and Methods: This is a retrospective analysis of 45 patients that underwent MRI examinations and the lesions were pathologically diagnosed as endometrial carcinoma after surgical resection. This study evaluated the staging accuracy of T2-weighted imaging, diffusion-weighted imaging (DWI), ADC mapping and T1-weighted imaging with fat saturation before and after gadolinium injection. Results: In 36 of the 45 cases, the MRI of the lesion showed the characteristics of endometrial cancer and the diagnosis was certain. Nine lesions (20%) were described as unequivocal and had unspecific MR appearance. In eight of the nine cases (89%), the histopathologic report revealed the presence of leiomyomas and two of these cases (22%) were also associated with adenomyosis. The cause of underestimation in these patients was coexisting lesions exhibiting heterogenous intensity and contrast enhancement, which made it difficult to detect the margins of the lesions. The depth of the myometrial invasion was underestimated in nine cases and overestimated in three cases. The staging accuracy with MRI was 74%. There was a significant correlation between MR imaging and histopathologic finding in the assessment of myometrial invasion (p < 0.001). Cervical extension was noted in eight cases (18%), but was missed on MR imaging in two patients and overstaged in none. Six of them were associated with myometrial invasion in more than 50% of the thickness. There was a significant correlation between MR imaging and histopathologic finding in the assessment of cervical extension (p < 0.001). Conclusions: Our data confirm the high accuracy of MRI in the diagnosis and local staging of endometrial carcinoma. The information provided by MRI has an important role in planning the treatment and the prognosis of the patients.

Accuracy of MRI in predicting deep myometrial invasion in endometrial cancer and the influence of leiomyoma, adenomyosis and the microcystic elongated and fragmented tumour pattern.

The most common form of endometrial cancer is Type 1 endometrioid adenocarcinoma. Depth of myometrial invasion is the most important prognostic factor correlating with overall patient survival. The objective was to investigate how accurate magnetic resonance imaging (MRI) is in predicting the depth of myometrial invasion in preoperative assessment, and the influence of leiomyoma and/or adenomyosis, or microcystic, elongated and fragmented (MELF) pattern of invasion on MRI diagnostic performance. Retrospective audit of 235 endometrial cancer patients from the regional Gynaecology Oncology multidisciplinary meeting at Auckland City Hospital, between January 2020 and January 2021. Radiologist assigned stage was compared to histopathology. Presence of leiomyoma, adenomyosis andMELF pattern evaluated followed by analysis under a Biostatistician's supervision. Overall MRI diagnostic accuracy for depth of myometrial invasion was 86%. For deep myometrial invasion, MRI had a sensitivity of 72% and specificity 91%. Out of the misreported 32/235 cases, 16 demonstrated fibroids and/or adenomyosis leading to a sensitivity of 57% and specificity 93% for deep invasion, compared with 94% and 74% respectively in the population without, demonstrating statistical significance. Thirty seven cases with MELF pattern of invasion showed a sensitivity of 81% and specificity 80% for deep invasion, compared with 63% and 92% respectively in the group without, demonstrating no statistical significance. MRI assessment of the depth of myometrial invasion in endometrial cancer has high accuracy. In the presence of background uterine fibroids/adenomyosis, pre-operative MRI accuracy of evaluating deep invasion shows a statistically significant reduction.

Diagnostic accuracy of MRI for evaluating myometrial invasion in endometrial cancer: a comparison of MUSE-DWI, rFOV-DWI, and DCE-MRI.

To compare the image quality of high-resolution diffusion-weighted imaging (DWI) using multiplexed sensitivity encoding (MUSE) versus reduced field-of-view (rFOV) techniques in endometrial cancer (EC) and to compare the diagnostic performance of these techniques with that of dynamic contrast-enhanced (DCE) MRI for assessing myometrial invasion of EC. MUSE-DWI and rFOV-DWI were obtained preoperatively in 58 women with EC. Three radiologists assessed the image quality of MUSE-DWI and rFOV-DWI. For 55 women who underwent DCE-MRI, the same radiologists assessed the superficial and deep myometrial invasion using MUSE-DWI, rFOV-DWI, and DCE-MRI. Qualitative scores were compared using the Wilcoxon signed-rank test. Receiver operating characteristic analysis was performed to compare the diagnostic performance. Artifacts, sharpness, lesion conspicuity, and overall quality were significantly better with MUSE-DWI than with rFOV-DWI (p < 0.05). The area under the curve (AUC) of MUSE-DWI, rFOV-DWI, and DCE-MRI for the assessment of myometrial invasion were not significantly different except for significantly higher AUC of MUSE-DWI than that of DCE-MRI for superficial myometrial invasion (0.76 for MUSE-DWI and 0.64 for DCE-MRI, p = 0.049) and for deep myometrial invasion (0.92 for MUSE-DWI and 0.80 for DCE-MRI, p = 0.022) in one observer, and that of rFOV-DWI for deep myometrial invasion in another observer (0.96 for MUSE-DWI and 0.89 for rFOV-MRI, p = 0.048). MUSE-DWI exhibits better image quality than rFOV-DWI. MUSE-DWI and rFOV-DWI shows almost equivalent diagnostic performance compared to DCE-MRI for assessing superficial and deep myometrial invasion in EC although MUSE-DWI may be helpful for some radiologists.

The role of preoperative transvaginal ultrasound in evaluating the myometrial invasion depth in women with endometrial cancer

Aim: The aim of our study was to compare the results of transvaginal ultrasonography (TVS) and final pathology in the determination of the depth of myometrial invasion in endometrial cancer preoperatively. Methods: The study was conducted as prospective observational study in a tertiary center between August 2012 -July 2012 and included 29 patients between the ages of 43 and 83 with endometrial biopsy results. Patients with endometrium cancer dignosis based on endometrial biopsy results were enrolled. Results: Transvaginal endometrial thickness was thicker for patients with myometrial invasion greater than � according to final pathology results, but this result was not statistically significant. When the patients were classified according to their surgical stages, 13 patients were stage 1a, 5 patients were stage 1b, 3 patients were stage 2, 6 patients stage 3, 2 patients stage 4. Final pathology of myometrial invasion greater than � patients compared with patients with thinner endometrium regarding age (p=0.003), gravidity (p=0.111), parity (p=0.135), weight (p=0.764), platelets (p= 0.831), CA125 (p=0.247) respectively. The age of patients were not statistically significant in comparison with tumor stage (p= 0.80). No statistical difference was observed when final pathology and transvaginal ultrasound results regarding myometrial invasion were compared (p= 1). We found that the sensitivity of preoperative transvaginal ultrasound for evaluation of myometrial invasion which is lesser than � was 77.7%. When final pathology and frozen section results were compared no significant statistical difference was found. (p=0.14). Conclusion: In our study, we compared the results of myometrial invasion in patients with pathologic and ultrasonographic findings and we found no statistically significant difference.

Ultrasonography, macroscopy, and frozen section: whıch is better for predicting deep myometrial invasıon in endometrial cancer?

The aim of this study was to compare the power of preoperative transvaginal ultrasonography, intraoperative macroscopic examination, and frozen section for predicting deep myometrial invasion in endometrial cancer. This is a retrospective review involving 68 patients who underwent surgical staging for endometrial cancer from 2014 to 2017. Patients with grade 3 endometrial cancer and non-endometrioid tumors were excluded. The findings related to preoperative transvaginal ultrasonography, intraoperative macroscopic examination, and frozen section were compared with definitive histopathological diagnosis. The mean age, gravidity, and body mass index of the patients were 58.1±8.9 years (range: 30-80 years), 3.2±2.1 (range: 0-9), and 33.5±6.6 kg/m2 (range: 20-52 kg/m2), respectively. Only 11 (16.2%) patients were in the premenopausal period, while 57 (83.8%) were in the postmenopausal period. Grade 1 endometrial cancer was found in 29 patients (42.6%) and grade 2 tumors were specified in 39 patients (57.4%). Stage IA disease was found in 45 (66.2%) patients, while stage IB disease was observed in 23 (33.8%) patients. The 5-year survival rate was 91.2%. The sensitivity of preoperative transvaginal ultrasonography, intraoperative macroscopic examination, and frozen section were 56, 34, and 52%, respectively, for predicting deep myometrial invasion. In contrast, the specificity of preoperative ultrasonography, intraoperative macroscopic examination, and frozen section were 86, 100, and 100%, respectively. Transvaginal ultrasonography and intraoperative frozen section were found to have similar sensitivity and specificity for predicting deep myometrial invasion. Preoperative transvaginal ultrasonography appears as an efficient approach for predicting endometrial cancers with deep myometrial invasion.

Study on Preoperative Neutrophil/Lymphocyte (NLR) and Platelet/Lymphocyte Ratio (PLR) as a Predictive Factor in Endometrial Cancer.

To evaluate predictive factors between serum inflammatory markers and malignancy potential of endometrium. This retrospective study was conducted at the gynecological oncology unit, department of obstetrics and gynecology, at the faculty of medicine of Thammasat University. The study period was from 2017 to 2020. Endometrial cancer and benign gynecologic disease cases who underwent hysterectomy (with or without adnexectomy) during the study period were recruited. Demographic characteristics, histopathology reports and serum markers were also collected. The study included a study group of 49 participants with endometrial cancer and a control group consisting of 119 cases of benign uterine disease. The study group had statistically significantly higher mean ages, proportional menopausal status and instances of underlying diseases when compared with the control group. Neutrophil/Lymphocyte ratios (NLR) and Platelet/Lymphocyte ratios (PLR) could not meaningfully predict the malignant potential of endometrium in hysterectomy specimens. NLR and PLR were statistically associated with depth of myometrial invasion (MI) in endometrial cancer cases. NLR equal to or greater than 1.93 predicted MI more than half thickness with sensitivity, specificity, accuracy, positive (PPV) and negative predictive value (NPV) at a percentage of 83.3, 52.8, 37.0, 90.5 and 60.4, respectively. PLR equal to or greater than 134.95 predicted MI of greater than fifty percent thickness with sensitivity, specificity, accuracy, PPV and NPV at 75.0, 55.6, 36.0, 87.0 and 60.4 percent, respectively. NLR and PLR have positive associations with myometrial invasion of endometrial cancer.

Preoperative ultrasound assessment of myometrial invasion in endometrial cancer and prediction of surgical stage

The aim of the study was to determine the performance of two-dimensional transvaginal ultrasonography (TVUS) in the preoperative assessment of myometrial invasion and cervical stromal invasion (CSI) in women diagnosed with endometrial cancer. Two-dimensional transvaginal ultrasound was performed prior to the diagnostic procedure and before surgical treatment. Myometrial invasion was assessed by measuring the ratio between the endometrial thickness and the antero-posterior diameter of the uterus in the midsagittal plane, by measuring of the smallest tumor-free margin of myometrium and was modified by the subjective assessment of the investigator. Cervical stromal invasion of the tumor was assessed by measuring the distance between the lowest detectable point of the tumor and the internal cervical os. Patients were operated by open surgery, laparoscopic or robot-assisted methods. No statistical difference was found between the number of preoperatively assessed patients (n = 161/180, 89.4%) and those with confirmed diagnosis after surgery (n = 144/180, 80%), (p > 0.05). Before surgery, 55.9% (n = 90/161) of cases were assessed with invasion <50% by TVUS, and 56.3% (n = 81/144) were confirmed after surgery. Cases assessed with invasion of >50% before surgery were 44.1% (n = 71/161). Surgery confirmed 43.8% (n = 63/144) of cases. No myometrial invasion was found preoperatively in 19 cases, using TVUS as a diagnostic tool. After surgery, in 36 cases no myometrial invasion was found. We found more cases with Grade 1 tumor (n = 29/81, 35.8%) when myometrial invasion was less than 50% compared to predominance of Grade 2 (n = 45/63, 71.4%) and Grade 3 (n = 15/63, 23.8%) tumor when invasion was more than 50% (p < 0.01).

Transvaginal three-dimensional ultrasound for preoperative assessment of myometrial invasion in patients with endometrial cancer: a systematic review and meta-analysis.

The aim of this meta-analysis is to evaluate the diagnostic accuracy of three-dimensional transvaginal ultrasound subjective assessment (3D-TVS) in the preoperative detection of deep myometrial invasion (MI) in patients with endometrial cancer, using definitive frozen section diagnosis after surgery as the reference standard. A search for studies evaluating the role of 3D-TVS for assessing myometrial invasion in endometrial cancer from January 1990 to Novem-ber 2020 was performed in PubMed/MEDLINE and Web of Science. The Quality Assessment of Diagnostic Accuracy Studies 2 evaluated the quality of the studies (QUADAS-2). All analyses were performed using MIDAS and METANDI commands. Nine studies comprising 581 women were included. The mean prevalence of deep MI was 39.8%. QUADAS as-sessment showed that most studies had a high risk for the patient selection domain. Overall, the pooled estimated sensitivity, specificity, positive likelihood and negative likelihood ratio of 3D-TVS for detecting deep MI were 84% (95% CI, 73-90%), 82% (95% CI, 75-88%), 5 (95% CI, 3.1-7.1) and 0.20 95% CI, 0.11-0.35). respectively. 3D-TVS has an accept-able diagnostic performance for detecting MI in women with endometrial cancer.

OC13.05: Three‐dimensional ultrasound in evaluation of myometrial invasion in endometrial cancer

OC13.05: Three‐dimensional ultrasound in evaluation of myometrial invasion in endometrial cancer

Diffusion-weighted imaging versus dynamic contrast-enhanced imaging for pre-operative diagnosis of deep myometrial invasion in endometrial cancer: A meta-analysis

PurposeThis study investigates the differences in diagnostic performance between diffuse-weighted imaging (DWI) and dynamic contrast-enhanced imaging (DCE), either alone or in combination with T2-weighted imaging (T2WI), for diagnosing deep myometrial invasion (dMI) of endometrial cancers (EC). MethodsWe performed a comprehensive search for published studies comparing DWI and DCE for preoperatively diagnosing dMI of EC. The overall diagnostic accuracy of each test was calculated using the areas under the summary receiver operating characteristic curves (AUCs). The sensitivities and specificities were compared using bivariate meta-regression. ResultsPooled analysis of nineteen studies with 961 patients (main group) showed that DWI had a larger AUC (0.943, 95% confidence interval (CI) = 0.921–0.967) than DCE (0.922, 95% CI = 0.893–0.953). For the subgroup comprising 7 studies, DWI combined with T2WI and DCE combined with T2WI showed AUCs of 0.959 (95% CI, 0.932–0.986) and 0.929 (95% CI, 0.847–1.000), respectively. None of the differences in AUCs were statistically significant. All comparisons of the sensitivities and specificities of the main group and subgroup also showed no significant differences. ConclusionThis meta-analysis found no significant difference in diagnostic performance between DWI and DCE for diagnosis of dMI in EC. DWI may be preferred for its ease of use in clinical practice.

Preoperative Magnetic Resonance Imaging versus Intraoperative Frozen Section Diagnosis for Predicting the Deep Myometrial Invasion in Endometrial Cancer: Our Experience and Literature Review.

The present study was designed to directly compare the diagnostic performance of preoperative magnetic resonance imaging (MRI) and intraoperative frozen section (FS) diagnoses in predicting deep myometrial invasion (MI) of endometrial cancer. Using MRI findings and FS diagnoses, 194 patients with surgically staged endometrial cancer were evaluated for deep MI between 2006 and 2018. Definitive histological diagnosis of paraffin sections of excised tissues was used as the gold standard approach. Of 194 cases, 53 (27.3%) cases were finally diagnosed as having deep MI (≥50%). There was 82% total agreement between MRI and FS diagnoses in predicting deep MI, with a kappa value of 0.54 (95% confidence interval [CI]=0.40-0.67, moderate agreement). The sensitivity of FS diagnosis (0.66, 95%CI=0.52-0.78) for predicting deep MI was lower than that of MRI (0.77, 95%CI=0.63-0.87; p=0.21), while the specificity of FS (0.98, 95%CI=0.93-0.99) was significantly higher than that of MRI (0.88, 95%CI=0.81-0.93; p=0.001). Overall, the accuracy of FS (0.89, 95%CI=0.84-0.93) was higher than that of MRI (0.85, 95%CI=0.79-0.90), although the difference did not reach statistical significance (p=0.23). The accuracy (0.95, 95%CI=0.90-0.97) was very high in cases with concordant MRI and FS results. MRI and FS showed different diagnostic characteristics for predicting deep MI, with a higher specificity observed for FS and the greatest accuracy obtained in concordant cases. Thus, our findings recommend the addition of FS diagnosis, either alone or in conjunction with MRI, to MI evaluation.

Preoperative predictive model of surgical planning in endometrial carcinoma using MRI and tumor grade in endometrial biopsy

Introduction: Endometrial cancer (EC) is the most common gynecological cancer in developed countries. Histological grade (G) and myometrial invasion (MI) are important risk factors, and together with the histological type and other postoperative data establish the risk of lymph node involvement and guide the adjuvant treatments. The objective of this study was to assess the validity of a preoperative stratification model that combines preoperative histological grade and MI as identified by magnetic resonance imaging (MRI) to select candidates for lymph node staging and optimize surgical planning for our patients. Material and methods: It´s an observational retrospective cohort study including 294 patients diagnosed with EC at Donostia University Hospital from January 2012 to December 2017. Preoperative endometrial biopsy, including histological type and grade, preoperative MRI was compared with the definitive histological diagnosis. Sensitivity (Sn), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) of the MRI-based diagnosis were calculated. Results: After inclusion and exclusion criteria 242 cases of type I or II EC were analyzed. Our model was found to have a Se of 91.4% (95% CI 83.2-95.8) and a Sp of 90.7% (95% CI 85.2-94.3). Percentage of down staging was 6.2% (15 unnecessary lymphadenectomies) and the upstaging rate was 2.9%. The NPV of the model was very high (95.4%, 95% CI 90.9-97.8). The diagnostic odds ratio for our model was 147.95 (95% CI 52.9-410.5), with a diagnostic accuracy of 91.7% (95% 87.6-94.6). Conclusions: A preoperative strategy that includes the determination of the tumor grade based on an endometrial biopsy and an assessment of MI by MRI is of great help in pre-surgical planning for endometrial cancer surgery, allowing an extra peritoneal approach and optimizing the use of physical and human resources. MRI presents excellent discriminatory power in the detection of MI in EC, with no significant variation by pathological subtype.

Abstract PO048: Inhibition of P300 histone acetyltransferase activity rescues invasive phenotypes of ARID1A-deficient endometrial epithelium

Abstract Invasion is a hallmark feature of endometrial pathologies, including myometrial invasion of endometrial cancer and invasion of distal sites during endometriosis. Mutations in the chromatin remodeling protein ARID1A have been observed at high rates in endometrial cancer and endometriosis. ARID1A loss, in combination with phosphoinositide 3-kinase (PI3K) pathway activation, has been shown to induce invasion phenotypes in the endometrial epithelium. Using bioinformatic approaches, we identified histone acetyltransferase (HAT) protein P300 as potential co-regulator of ARID1A-deficient gene expression programs. Knockdown of P300 prevented invasive phenotypes in a genetically engineered mouse model and human endometrial epithelial cells through induction of apoptosis, indicating a synthetic-lethal relationship between ARID1A and P300 in the endometrial epithelium. Using the novel HAT inhibitor, A-485, we identified P300 HAT activity as the mechanism by which P300 promotes invasive phenotypes. A-485 treatment rescued invasion in vitro at concentrations which had no effect on cell viability in adherent culture, but induced anoikis in suspension culture. Using an RNA-seq approach, we identified cell adhesion and migration pathways as being regulated by ARID1A knockdown and P300 co-knockdown or A-485 co-treatment. Among genes in these pathways, we identified SERPINE1 as an essential component of P300-dependent invasive processes. SERPINE1 is overexpressed following ARID1A loss in mouse and human models, and SERPINE1 knockdown rescued invasive phenotypes following ARID1A loss. By chromatin immunoprecipitation, we identified a role for P300-dependent acetylation of histone 3 lysine 27 (H3K27ac) at the SERPINE1 super-enhancer. The novel P300 bromodomain inhibitor CCS1477 also rescues invasion and SERPINE1 expression following ARID1A loss, suggesting a role for bromodomain inhibition as a modulator of P300 H3K27ac deposition. These studies suggest the therapeutic utility of P300 inhibition to induce anoikis in mutant endometrium which has detached from the basement membrane, thereby preventing invasion. Citation Format: Mike R. Wilson, Jake J. Reske, Ronald L. Chandler. Inhibition of P300 histone acetyltransferase activity rescues invasive phenotypes of ARID1A-deficient endometrial epithelium [abstract]. In: Proceedings of the AACR Virtual Special Conference: Endometrial Cancer: New Biology Driving Research and Treatment; 2020 Nov 9-10. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(3_Suppl):Abstract nr PO048.

High resolution diffusion-weighted imaging with readout segmentation of long variable echo-trains for determining myometrial invasion in endometrial carcinoma

BackgroundWe assessed the image quality of endometrial cancer lesions by readout segmentation of long variable echo-trains (RESOLVE) diffusion-weighted imaging (DWI) compared with that by single-shot echo-planar imaging (SS-EPI) DWI, aimed to explore the value of RESOLVE DWI for determining myometrial invasion and clinical stage in endometrial cancer.Materials and methodsFrom April 2017 to March 2018, a total of 30 endometrial cancer patients (mean age 52.8 ± 9.0 years), who had undergone RESOLVE DWI and SS-EPI DWI, were included in the study. The image quality of endometrial carcinoma by two kinds of DWI scanning methods was compared qualitatively and quantitatively. The Spearman rank correlation test was used to assess the correlation of qualitative image quality scores between two readers. The accuracy of two DWI methods in detecting myometrial invasion and staging of endometrial carcinoma was calculated according to postoperative pathological results. The indexes were analyzed including sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV).ResultsThe qualitative score of RESOLVE DWI group was superior to SS-EPI DWI group in every aspect of five aspects (all P < 0.001). Interobserver agreement of depiction was good or excellent in two DWI sequences. Signal to noise ratio and contrast to noise ratio values in RESOLVE DWI group were both higher than those in SS-EPI DWI group (P<0.001). No statistical difference of apparent diffusion coefficient value was observed between two DWI groups (P = 0.261). The specificity, accuracy, PPV, and NPV of estimating myometrial invasion by RESOLVE DWI in three cases (intramucosal lesion, <50% superficial invasion and ≥ 50% deep invasion) were all higher than those by SS-EPI DWI for endometrial carcinoma. Especially RESOLVE DWI was valuable in judging <50% superficial invasion (95%CI:0.586, 0.970). No significant difference in accuracy staging was between the two DWI groups (P = 0.125).ConclusionRESOLVE DWI can provide higher quality images of endometrial carcinoma than SS-EPI DWI. The high-quality images are helpful for precise assessment of myometrial invasion in endometrial cancer.

Predicting myometrial invasion in endometrial cancer based on whole-uterine magnetic resonance radiomics.

The objective of this study was to evaluate whether whole-uterine magnetic resonance imaging (MRI) radiomic features can predict myometrial invasion (MI) depth in endometrial cancer (EC). The preoperative 3.0 T magnetic resonance examinations of EC patients were retrospectively reviewed. Whole-uterus segmentation was performed, and features were extracted based on sagittal T2-weighted imaging (T2WI) and axial diffusion-weighted imaging (DWI). The logistic regression (LR) classifier algorithm was used to establish the radiomic model, which was verified by ten times five-fold cross-validation. The areas under the receiver operating characteristic (ROC) curves (AUCs) were assessed by the DeLong test to compare differences among the models based on different sequences. The LR model was compared with the subjective diagnosis results by the Chi-square test. Of the 163 EC patients included, 44 had deep myometrial invasion (DMI). The feature consistency of the whole uterus was higher than that of the lesion (P < 0.05). The sagittal T2WI, axial DWI, and combined models had AUCs of 0.76, 0.80, and 0.85 in the validation set, respectively. The DeLong test showed that there were no significant differences in AUCs among the models (P > 0.05). The single-sequence LR models had lower specificity and accuracy than the corresponding subjective diagnostic results (P < 0.05), while the sensitivity was higher (P > 0.05). The combined model included 24 radiomic features, and the accuracy, sensitivity, and specificity were 0.83, 0.77, and 0.85 for DMI, respectively. There was no significant difference compared with subjective diagnosis (P > 0.05). Whole-uterine MRI radiomic features based on sagittal T2WI and axial DWI show potential in predicting MI in EC.

OP07.02: Assessment of myometrial invasion in endometrial cancer by transvaginal sonography versus magnetic resonance

OP07.02: Assessment of myometrial invasion in endometrial cancer by transvaginal sonography versus magnetic resonance

Diagnostic yield of magnetic resonance imaging and intraoperative frozen section in the determination of deep myometrial invasion in endometrial cancer

Background and objectivesThe standard treatment for endometrial cancer is simple hysterectomy with bilateral salpingo-oophorectomy. Patients with high risk also benefit from lumbo-aortic lymphadenectomy. High risk patients include those with grades and histologic subtypes associated with poor prognosis and depth of myometrial invasion greater than 50% (M2). To determine which patients would benefit from lumbo-aortic lymphadenectomy, the depth of myometrial invasion can be assessed by intraoperative frozen section or by magnetic resonance imaging (MRI). We aimed to determine the diagnostic yield of intraoperative frozen section and MRI for detecting the presence of M2 in patients with endometrial cancer. Materials and methodsThis cross-sectional study included women with a histologically confirmed diagnosis of endometrial cancer who underwent baseline MRI and surgical intervention in our institution between 1 January 2010 and 31 December 2017. We reviewed the MRI studies and the intraoperative frozen section reports and compared them with the information in the histopathology report. We compared the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the two tests. We also calculated the diagnostic accuracy of each method and the percentages of underestimation and overestimation. Finally, we calculated the predictive value of MRI for the presence of M2, adjusting it for the histologic variables known to be associated with poor prognosis. ResultsTo detect M2, MRI had 63% sensitivity, 87% specificity, 73% PPV, and 81% NPV; the diagnostic accuracy was 78.8%, with 13.12% underestimation and 8.13% overestimation of M2. Intraoperative frozen section had 69% sensitivity, 86.7% specificity, 69% PPV, and 86% NPV; the diagnostic accuracy was 81.5%, with 9.24% underestimation and 9.24% overestimation of M2. The degree of concordance between the two methods was moderate (k=0.54, p<0.00001). ConclusionsIn our experience, MRI and intraoperative frozen section have adequate diagnostic yields for determining M2, though intraoperative frozen section is slightly better. The contribution of MRI in determining the presence and the site of deep myometrial invasion, as well as the factors that can confound the diagnosis, when added to the contribution of intraoperative frozen section, means that both methods help reduce the number of unnecessary lymph node dissections and the morbidity, mortality, and health costs associated with this practice.

The added value of diffusion-weighted imaging in the preoperative assessment of endometrial cancer.

ObjectiveTo evaluate the added value of diffusion-weighted imaging (DWI) in the preoperative assessment of myometrial invasion in endometrial cancer, in comparison with T2-weighted imaging (T2WI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).Materials and MethodsThis was a retrospective study involving 44 women with endometrial cancer who underwent preoperative 1.5 T MRI. Two radiologists, both of whom were blinded to the histopathology reports, performed a consensus interpretation of the depth of myometrial invasion and of the stage of the cancer, considering three sets of sequences: T2WI, DCE-MRI+T2WI, and DWI+T2WI. Accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were calculated for each set. The accuracy was compared with p-value adjustment by the Benjamini-Hochberg procedure. ResultsAmong the 44 patients evaluated, DWI+T2WI demonstrated better diagnostic performance in assessing deep myometrial invasion and correctly staged more patients (n = 41) than did DCE-MRI+T2WI (n = 34) and T2WI (n = 22). The superior diagnostic accuracy of DWI+T2WI was statistically significant in comparison with T2WI (p < 0.05) but not in comparison with DCE-MRI+T2WI (p > 0.05).ConclusionThe addition of DWI apparently improves the diagnostic accuracy of MRI in the preoperative assessment of the depth of myometrial invasion in endometrial cancer, which may be particularly helpful in patients for whom contrast agents are contraindicated.