Diagnostic efficacy of diffusion-weighted MRI for pre-operative assessment of myometrial and cervical invasion and pelvic lymph node metastasis in endometrial carcinoma

Risk factors associated with false negative rate of sentinel lymph node biopsy in endometrial cancer: a systematic review and meta-analysis

Objective

Currently, sentinel lymph node biopsy (SLNB) is increasingly used in endometrial cancer, but the rate of missed metastatic lymph nodes compared to systemic lymph node dissection has been a concern. We conducted a systematic review and meta-analysis to evaluate the false negative rate (FNR) of SLNB in patients with endometrial cancer and to explore the risk factors associated with this FNR.

Data sources

Three databases (PubMed, Embase, Web of Science) were searched from initial database build to January 2023 by two independent reviewers.

Research eligibility criteria

Studies were included if they included 10 or more women diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage I or higher endometrial cancer, the study technique used sentinel lymph node localization biopsy, and the reported outcome metrics included false negative and/or FNR.

Study appraisal and synthesis methods

Two authors independently reviewed the abstracts and full articles. The FNR and factors associated with FNR were synthesized through random-effects meta-analyses and meta-regression.

The results

We identified 62 eligible studies. The overall FNR for the 62 articles was 4% (95% CL 3-5).There was no significant difference in the FNR in patients with high-risk endometrial cancer compared to patients with low-risk endometrial cancer. There was no difference in the FNR for whether frozen sections were used intraoperatively. The type of dye used intraoperatively (indocyanine green/blue dye) were not significantly associated with the false negative rate. Cervical injection reduced the FNR compared with alternative injection techniques. Indocyanine green reduced the FNR compared with alternative Tc-99m. Postoperative pathologic ultrastaging reduced the FNR.

Conclusions

Alternative injection techniques (other than the cervix), Tc-99m dye tracer, and the absence of postoperative pathologic ultrastaging are risk factors for a high FNR in endometrial cancer patients who undergo SLNB; therefore, we should be vigilant for missed diagnosis of metastatic lymph nodes after SLNB in such populations.

Systematic review registration

http://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023433637.

Incorporation of Tumor-Free Distance and Other Alternative Ultrasound Biomarkers into a Myometrial Invasion-Based Model Better Predicts Lymph Node Metastasis in Endometrial Cancer: Evidence and Future Prospects

Myometrial invasion (MI) is a parameter currently used in transvaginal ultrasound (TVS) in endometrial cancer (EC) to determine local staging; however, without molecular diagnostics, it is insufficient for the selection of high-risk cases, i.e., those with a high risk of lymph node metastases (LNM). The study’s objective was to answer the question of which TVS markers, or their combination, reflecting the molecular changes in EC, can improve the prediction of LNM. Methods: The TVS examination was performed on 116 consecutive EC patients included in this prospective study. The results from the final histopathology were a reference standard. Univariate and multivariate logistic models of analyzed TVS biomarkers (tumor [T] size, T area [AREA], T volume [SPE-VOL], MI, T-free distance to serosa [TFD], endo-myometrial irregularity, [EMIR], cervical stromal involvement, CSI) were evaluated to assess the relative accuracy of the possible LNM predictors., Spline functions were applied to avoid a potential bias in assuming linear relations between LNM and continuous predictors. Calculations were made in R using libraries splines, glmulti, and pROC. Results: LNM was found in 20 out of the 116 (17%) patients. In univariate analysis, only uMI, EMIR, uCSI and uTFD were significant predictors of LNM. The accuracy was 0.707 (AUC 0.684, 95% CI 0.568−0.801) for uMI (p < 0.01), 0.672 (AUC 0.664, 95% CI 0.547−0.781) for EMIR (p < 0.01), 0.776 (AUC 0.647, 95% CI 0.529−0.765) for uCSI (p < 0.01), and 0.638 (AUC 0.683, 95% CI 0.563−0.803) for uTFD (p < 0.05). The cut-off value for uTFD was 5.2 mm. However, AREA and VOL revealed a significant relationship by nonlinear analysis as well. Among all possible multivariate models, the one comprising interactions of splines of uTFD with uMI and splines of SPE-VOL with uCSI showed the most usefulness. Accuracy was 0.802 (AUC 0.791, 95% CI 0.673−0.91) Conclusions: A combination of uTFD for patients with uMI > 50%, and SPE-VOL for patients with uCSI, allows for the most accurate prediction of LNM in EC, rather than uMI alone.

Diagnostic value of integrated 18F-FDG PET/MRI for staging of endometrial carcinoma: comparison with PET/CT

Purpose

To explore the diagnostic value of integrated positron emission tomography/magnetic resonance imaging (PET/MRI) for the staging of endometrial carcinoma and to investigate the associations between quantitative parameters derived from PET/MRI and clinicopathological characteristics of endometrial carcinoma.

Methods

Altogether, 57 patients with endometrial carcinoma who underwent PET/MRI and PET/computed tomography (PET/CT) preoperatively were included. Diagnostic performance of PET/MRI and PET/CT for staging was compared by three readers. Associations between PET/MRI quantitative parameters of primary tumor lesions and clinicopathological characteristics of endometrial carcinoma were analyzed. Histopathological results were used as the standard.

Results

The overall accuracy of the International Federation of Gynecology and Obstetrics (FIGO) staging for PET/MRI and PET/CT was 86.0% and 77.2%, respectively. PET/MRI had higher accuracy in diagnosing myometrial invasion and cervical invasion and an equivalent accuracy in diagnosing pelvic lymph node metastasis against PET/CT, although without significance. All PET/MRI quantitative parameters were significantly different between stage I and stage III tumors. Only SUV_max/ADC_min were significantly different between stage I and II tumors. No parameters were significantly different between stage II and III tumors. The SUV_max/ADC_min in the receiving operating characteristic (ROC) curve had a higher area under the ROC curve for differentiating stage I tumors and other stages of endometrial carcinoma.

Conclusions

PET/MRI had a higher accuracy for the staging of endometrial carcinoma, mainly for FIGO stage I tumors compared to PET/CT. PET/MRI quantitative parameters, especially SUV_max/ADC_min, were associated with tumor stage and other clinicopathological characteristics. Hence, PET/MRI may be a valuable imaging diagnostic tool for preoperative staging of endometrial carcinoma.

Magnetic resonance imaging pitfalls in determining myometrial invasion in stage I endometrial cancer: A case report and literature review

The degree of myometrial invasion (MI) is crucial in the preoperative diagnosis of endometrial cancer (EC) using MRI in terms of therapeutic and prognostic implications. However, several pitfalls should be kept in mind when using this modality. We report a case of EC on a 64-year-old woman, identified preoperatively without MI based on ultrasonography and MRI, implying a low risk of lymph node metastasis; surprisingly, the uterine incision showed the lesion had invaded <50% of the myometrium. Thus, a total laparoscopic hysterectomy and bilateral salpingo-oophorectomy were performed, and histopathologic analysis confirmed that the EC was on stage IA (cancer is in the endometrium only or less than halfway through the myometrium). In our case, thinning myometrium and uterine atrophy due to aging, multiple leiomyomas, previous curettage, and blood clots were all pitfalls for MRI in detecting MI. By detecting tiny or isointense tumors and depicting distinct vascularity of the malignancy in postmenopausal women, functional MRI techniques such as diffusion-weighted imaging (DWI) and dynamic contrast-enhanced MRI (DCE-MRI) can help reduce pitfalls when assessing MI. Clinicians can employ DWI preoperatively, which is more reliable and superior to DCE-MRI in determining tumor areas without contrast injection and perform a postoperative histopathological examination to confirm MI in EC.

Vibrational Biospectroscopy: An Alternative Approach to Endometrial Cancer Diagnosis and Screening

Endometrial cancer (EC) is the sixth most common cancer and the fourth leading cause of death among women worldwide. Early detection and treatment are associated with a favourable prognosis and reduction in mortality. Unlike other common cancers, however, screening strategies lack the required sensitivity, specificity and accuracy to be successfully implemented in clinical practice and current diagnostic approaches are invasive, costly and time consuming. Such limitations highlight the unmet need to develop diagnostic and screening alternatives for EC, which should be accurate, rapid, minimally invasive and cost-effective. Vibrational spectroscopic techniques, Mid-Infrared Absorption Spectroscopy and Raman, exploit the atomic vibrational absorption induced by interaction of light and a biological sample, to generate a unique spectral response: a “biochemical fingerprint”. These are non-destructive techniques and, combined with multivariate statistical analysis, have been shown over the last decade to provide discrimination between cancerous and healthy samples, demonstrating a promising role in both cancer screening and diagnosis. The aim of this review is to collate available evidence, in order to provide insight into the present status of the application of vibrational biospectroscopy in endometrial cancer diagnosis and screening, and to assess future prospects.

European Society of Gynaecological Oncology quality indicators for the surgical treatment of endometrial carcinoma

BACKGROUND

Quality of surgical care as a crucial component of a comprehensive multi-disciplinary management improves outcomes in patients with endometrial carcinoma, notably helping to avoid suboptimal surgical treatment. Quality indicators (QIs) enable healthcare professionals to measure their clinical management with regard to ideal standards of care.

OBJECTIVE

In order to complete its set of QIs for the surgical management of gynecological cancers, the European Society of Gynaecological Oncology (ESGO) initiated the development of QIs for the surgical treatment of endometrial carcinoma.

METHODS

QIs were based on scientific evidence and/or expert consensus. The development process included a systematic literature search for the identification of potential QIs and documentation of the scientific evidence, two consensus meetings of a group of international experts, an internal validation process, and external review by a large international panel of clinicians and patient representatives. QIs were defined using a structured format comprising metrics specifications, and targets. A scoring system was then developed to ensure applicability and feasibility of a future ESGO accreditation process based on these QIs for endometrial carcinoma surgery and support any institutional or governmental quality assurance programs.

RESULTS

Twenty-nine structural, process and outcome indicators were defined. QIs 1-5 are general indicators related to center case load, training, experience of the surgeon, structured multi-disciplinarity of the team and active participation in clinical research. QIs 6 and 7 are related to the adequate pre-operative investigations. QIs 8-22 are related to peri-operative standards of care. QI 23 is related to molecular markers for endometrial carcinoma diagnosis and as determinants for treatment decisions. QI 24 addresses the compliance of management of patients after primary surgical treatment with the standards of care. QIs 25-29 highlight the need for a systematic assessment of surgical morbidity and oncologic outcome as well as standardized and comprehensive documentation of surgical and pathological elements. Each QI was associated with a score. An assessment form including a scoring system was built as basis for ESGO accreditation of centers for endometrial cancer surgery.

Ultrasound Measurement of Tumor-Free Distance from the Serosal Surface as the Alternative to Measuring the Depth of Myometrial Invasion in Predicting Lymph Node Metastases in Endometrial Cancer

Background: Ultrasonography’s usefulness in endometrial cancer (EC) diagnosis consists in its roles in staging and prediction of metastasis. Ultrasound-measured tumor-free distance from the tumor to the uterine serosa (uTFD) is a promising marker for these diagnostic and prognostic variables. The aim of the study was to determine the usefulness of this biomarker in locoregional staging, and thus in the prediction of lymph node metastasis (LNM). Methods: We conducted a single-institutional, prospective study on 116 consecutive patients with EC who underwent 2D transvaginal ultrasound examination. The uTFD marker was compared with the depth of ultrasound-measured myometrial invasion (uMI). Univariable and multivariable logit models were evaluated to assess the predictive power of the uTFD and uMI in regard to LNM. The reference standard was a final histopathology result. Survival was assessed by the Kaplan–Meier method. Results: LNM was found in 17% of the patients (20/116). In the univariable analysis, uMI and uTFD were significant predictors of LNM. The accuracy was 70.7%, and the NPV was 92.68% (OR 4.746, 95% CI 1.710–13.174) for uMI (p = 0.002), and they were 63.8% and 89.02% (OR 0.842, 95% CI 0.736–0.963), respectively, for uTFD (p = 0.01). The cutoff value for uTFD in the prediction of LNM was 5.2 mm. The association between absence of LNM and biomarker values of uMI < 1/2 and uTFD ≥ 5.2 mm was greater than that between the presence of metastases and uMI > 1/2 and uTFD values <5.2 mm. In the multivariable analysis, the accuracy of the uMI–uTFD model was 74%, and its NPV was 90.24% (p = non-significant). Neither uMI nor uTFD were surrogates for overall and recurrence-free survivals in endometrial cancer. Conclusions: Both uMI and uTFD, either alone or in combination, were valuable tools for gaining additional preoperative information on expected lymph node status. Negative lymph nodes status was better described by ultrasound biomarkers than a positive status. It was easier to use the uTFD rather than the uMI measurement as a biomarker of EC invasion, and the former still maintained a similar predictive value for lymph node metastases to the latter at diagnosis.

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

PURPOSE

This 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).

METHODS

We 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.

RESULTS

Pooled 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.

CONCLUSION

This 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.

ESGO/ESTRO/ESP guidelines for the management of patients with endometrial carcinoma

A European consensus conference on endometrial carcinoma was held in 2014 to produce multidisciplinary evidence-based guidelines on selected questions. Given the large body of literature on the management of endometrial carcinoma published since 2014, the European Society of Gynaecological Oncology (ESGO), the European SocieTy for Radiotherapy & Oncology (ESTRO) and the European Society of Pathology (ESP) jointly decided to update these evidence-based guidelines and to cover new topics in order to improve the quality of care for women with endometrial carcinoma across Europe and worldwide. ESGO/ESTRO/ESP nominated an international multidisciplinary development group consisting of practicing clinicians and researchers who have demonstrated leadership and expertise in the care and research of endometrial carcinoma (27 experts across Europe). To ensure that the guidelines are evidence-based, the literature published since 2014, identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, judgment was based on the professional experience and consensus of the development group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 191 independent international practitioners in cancer care delivery and patient representatives. The guidelines comprehensively cover endometrial carcinoma staging, definition of prognostic risk groups integrating molecular markers, pre- and intra-operative work-up, fertility preservation, management for early, advanced, metastatic, and recurrent disease and palliative treatment. Principles of radiotherapy and pathological evaluation are also defined.

ESGO/ESTRO/ESP Guidelines for the management of patients with endometrial carcinoma

A European consensus conference on endometrial carcinoma was held in 2014 to produce multidisciplinary evidence-based guidelines on selected questions. Given the large body of literature on the management of endometrial carcinoma published since 2014, the European Society of Gynaecological Oncology (ESGO), the European SocieTy for Radiotherapy & Oncology (ESTRO) and the European Society of Pathology (ESP) jointly decided to update these evidence-based guidelines and to cover new topics in order to improve the quality of care for women with endometrial carcinoma across Europe and worldwide. ESGO/ESTRO/ESP nominated an international multidisciplinary development group consisting of practicing clinicians and researchers who have demonstrated leadership and expertise in the care and research of endometrial carcinoma (27 experts across Europe). To ensure that the guidelines are evidence-based, the literature published since 2014, identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, judgment was based on the professional experience and consensus of the development group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 191 independent international practitioners in cancer care delivery and patient representatives. The guidelines comprehensively cover endometrial carcinoma staging, definition of prognostic risk groups integrating molecular markers, pre- and intra-operative work-up, fertility preservation, management for early, advanced, metastatic, and recurrent disease and palliative treatment. Principles of radiotherapy and pathological evaluation are also defined.

MRI to assess deep myometrial invasion in patients with endometrial cancer:A multi-reader study to evaluate the diagnostic role of different sequences

OBJECTIVE

The identification of deep myometrial invasion (DMI) represents a fundamental aspect in patients with endometrial cancer (EC) for accurate disease staging. It can be detected on MRI using T2-weighted (T2-w), diffusion weighted (DWI) and dynamic contrast enhanced sequences (DCE). Aim of the study was to perform a multi-reader evaluation of such sequences to identify the most accurate and its reliability for the best protocol.

METHODS

In this multicenter retrospective study, MRI were independently evaluated by 4 radiologists (2 senior and 2 novice) with a sequence-based approach to identify DMI. The performance of the entire protocol was also evaluated. A comparison between the different sequences assessed by the same reader was performed using receiver operating curve and post-hoc analysis. Intraclass Correlation Coefficient (ICC) was used to assess inter- and intra-observer variability.

RESULTS

A total of 92 patients were included. The performance of the readers did not show significant differences among DWI, DCE and the entire protocol. For only one senior radiologist, who reached the highest diagnostic accuracy with the entire protocol (82,6 %), both DWI (p = 0,0197) and entire protocol (p = 0,0039) were found significantly superior to T2-w. The highest inter-observer agreement was obtained with the entire protocol by expert readers (ICC = 0,77).

CONCLUSIONS

For the detection of DMI, the performances of DWI and DCE alone and that of a complete protocol do not significantly differ, even though the latter ensures the highest reliability particularly for expert readers. In cases in which T2-w and DWI are consistent, an unenhanced protocol could be proposed.

Diagnostic Accuracy of MRI for Detecting Cervical Invasion in Patients with Endometrial Carcinoma: A Meta-Analysis

Objectives: To evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) in the preoperative assessment of cervical invasion and to analyse the influence of different imaging protocols in patients with endometrial carcinoma.

Methods: An extensive search of articles about MRI for assessing cervical invasion in patients with endometrial carcinoma was performed on PubMed, Embase, Web of Science, Cochrane Library, and Clinical Trials from January 2000 to July 2020. Two reviewers independently evaluated the methodological quality of each study by using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). Diagnostic accuracy results and additional useful information were extracted. The pooled estimation data was obtained by statistical analysis.

Results: A total of 42 eligible studies were included in the meta-analysis. Significant evidence of heterogeneity was found for detecting cervical invasion (I² = 74.1%, P = 0.00 for sensitivity and I² = 56.2%, P = 0.00 for specificity). The pooled sensitivity and specificity of MRI were 0.58 and 0.95 respectively. The use of higher field strength (3.0 T) demonstrated higher pooled sensitivity (0.74). Using diffusion weighted imaging (DWI) alone presented higher pooled sensitivity (0.86) than using other sequences. The studies that used dynamic contrast-enhanced MRI (DCE-MRI) alone showed higher sensitivity (0.80) and specificity (0.96) than those that used T2-weighted imaging (T2WI) alone.

Conclusions: MRI shows high specificity for detecting cervical infiltration in endometrial carcinoma. Using DWI or a 3.0-T device may improve the pooled sensitivity. DCE-MRI demonstrates higher pooled sensitivity and specificity than T2WI.

ESGO/ESTRO/ESP guidelines for the management of patients with endometrial carcinoma

A European consensus conference on endometrial carcinoma was held in 2014 to produce multi-disciplinary evidence-based guidelines on selected questions. Given the large body of literature on the management of endometrial carcinoma published since 2014, the European Society of Gynaecological Oncology (ESGO), the European SocieTy for Radiotherapy and Oncology (ESTRO), and the European Society of Pathology (ESP) jointly decided to update these evidence-based guidelines and to cover new topics in order to improve the quality of care for women with endometrial carcinoma across Europe and worldwide.

Differential Impact of Systemic Lymphadenectomy Upon the Survival of Patients with Type I vs Type II Endometrial Cancer: A Retrospective Observational Cohort Study

PURPOSE

To determine whether systemic lymphadenectomy exerts a similar effect on the survival of patients with either type I or type II endometrial cancer (EC).

PATIENTS AND METHODS

In this retrospective study, 682 eligible patients diagnosed with EC were typed according to the pathological reports. The thoroughness of lymphadenectomy was evaluated by the lymph node number of which the cut-off value was determined by the receiver operator characteristic (ROC) curve and Youden index. The impact of thoroughness on the survival of both types was analyzed, respectively, by Kaplan Meier (K-M) method and further evaluated in subgroups with and without lymphatic metastasis. Independent prognostic factors of survival were selected by proportional hazard regression (Cox) model.

RESULTS

The cut-off level of lymph node number was 20. The differential impact of the lymph node number removed on survival was noted when patients with different types were analyzed separately. Among type II EC, those with >20 lymph nodes removed presented better overall survival (OS) than those with ≤20 (p=0.002). The number of lymph nodes removed >20 was proved as an independent factor for improved OS in type II EC (HR=0.329,95% CI: 0.123-0.881, p=0.0027). In the subgroup of type II with >20 lymph nodes resected, similar 5-year OS rates were observed in those with or without identified positive node (90.9% vs 92.9%, p=0.965). Type I EC seemed unbeneficial from such a procedure.

CONCLUSION

Systemic lymphadenectomy could enhance the OS of type II EC other than type I.

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.

The Diagnostic Value of MRI for Preoperative Staging in Patients with Endometrial Cancer: A Meta-Analysis

OBJECTIVES

To assess the diagnostic accuracy of magnetic resonance imaging (MRI) for detecting myometrial invasion, cervical invasion, and lymph node metastases in endometrial cancer.

MATERIALS AND METHODS

A systematic literature search was performed in PubMed, Embase, Cochrane Library, Web of Science, and Clinical trials. The methodological quality of each study was assessed by using the standard Quality Assessment of Diagnostic Accuracy Studies-2. Statistical analysis included evaluating publication bias, assessing threshold effect, exploring heterogeneity, pooling data, meta-regression, forest plot, and summary receiver-operating characteristics curves construction.

RESULTS

Fourteen studies could be analyzed. For detecting deep myometrial invasion, the pooled sensitivity and specificity were 0.79 and 0.81 respectively, and patients younger than 60 years old demonstrated higher sensitivity (0.84) and specificity (0.90). The diagnostic accuracy is highest by jointly using T2-weighted image, dynamic contrast-enhanced MRI, and diffusion weighted imaging to detect the deep myometrial invasion. There were low sensitivity and high specificity for the diagnosis of cervical invasion (0.53, 0.95), cervical stromal invasion (0.50, 0.95), pelvic or/and para-aortic lymph node metastases (0.59, 0.95), and pelvic lymph node metastases (0.65, 0.95).

CONCLUSION

MRI has good diagnostic performance for assessing myometrial invasion in patients with endometrial cancer, especially in patients younger than 60 years old. Dynamic contrast-enhanced MRI and diffusion weighted imaging can help improve sensitivity and specificity for detecting myometrial invasion. MRI shows high specificity for detecting cervical invasion and lymph node metastases in endometrial cancer.

Quantitative assessment of diffusion kurtosis imaging depicting deep myometrial invasion: a comparative analysis with diffusion-weighted imaging

PURPOSE

We aimed to investigate histogram analysis of diffusion kurtosis imaging (DKI) and conventional diffusion-weighted imaging (DWI) to distinguish between deep myometrial invasion and superficial myometrial invasion in endometrial carcinoma (EC).

METHODS

A total of 118 pathologically confirmed EC patients with preoperative DWI were included. The data were postprocessed with a DKI (b value of 0, 700, 1400, and 2000 s/mm2) model for quantitation of apparent diffusion values (D) and apparent kurtosis coefficient values (K) for non-Gaussian distribution. The apparent diffusion coefficient (ADC) was postprocessed with a conventional DWI model (b values of 0 and 800 s/mm2). A whole-tumor analysis approach was used. Comparisons of the histogram parameters of D, K, and ADC were carried out for the deep myometrial invasion and superficial myometrial invasion subgroups. Diagnostic performance of the imaging parameters was assessed.

RESULTS

The Dmean, D10th, and D90th in deep myometrial invasion group were significantly lower than those in superficial invasion group (P < 0.001, P < 0.001, and P = 0.023, respectively), as well as the ADCmean, ADC10th, and ADC90th (P = 0.001, P = 0.001, and P = 0.042, respectively). The Kmean and K90th were significantly higher in deep invasion group than those in superficial myometrial invasion group (P = 0.002 and P = 0.026, respectively). The D10th, Kmean, and ADC10th had a relatively higher area under the curve (AUC) (0.72, 0.66, and 0.71, respectively) than other parameters for distinguishing deep myometrial invasion of EC. D10th showed a relatively higher AUC than ADC10th for the differentiation of lesions with deep myometrial invasion from those with superficial myometrial invasion (0.72 vs. 0.71), but the variation was not statistically significant (P = 0.35).

CONCLUSION

Distribution of DKI and conventional DWI parameters characterized by histogram analysis may represent an indicator for deep myometrial invasion in EC. Both DKI and DWI models showed relatively equivalent effectiveness.

Multiplanar MRI-Based Predictive Model for Preoperative Assessment of Lymph Node Metastasis in Endometrial Cancer

Introduction: Assessment of lymph node metastasis (LNM) is crucial for treatment decision and prognosis prediction for endometrial cancer (EC). However, the sensitivity of the routinely used magnetic resonance imaging (MRI) is low in assessing normal-sized LNM (diameter, 0-0.8 cm). We aimed to develop a predictive model based on magnetic resonance (MR) images and clinical parameters to predict LNM in normal-sized lymph nodes (LNs). Materials and Methods: A total of 200 retrospective patients were enrolled and divided into a training cohort (n = 140) and a test cohort (n = 60). All patients underwent preoperative MRI and had pathological result of LNM status. In total, 4,179 radiomic features were extracted. Four models including a clinical model, a radiomic model, and two combined models were built. Area under the receiver operating characteristic (ROC) curves (AUC) and calibration curves were used to assess these models. Subgroup analysis was performed according to LN size. All patients underwent surgical staging and had pathological results. Results: All of the four models showed predictive ability in LNM. One of the combined models, ModelCR1, consisting of radiomic features, LN size, and cancer antigen 125, showed the best discrimination ability on the training cohort [AUC, 0.892; 95% confidence interval [CI], 0.834-0.951] and test cohort (AUC, 0.883; 95% CI, 0.786-0.980). The subgroup analysis showed that this model also indicated good predictive ability in normal-sized LNs (0.3-0.8 cm group, accuracy = 0.846; <0.3 cm group, accuracy = 0.849). Furthermore, compared with the routinely preoperative MR report, the sensitivity and accuracy of this model had a great improvement. Conclusions: A predictive model was proposed based on MR radiomic features and clinical parameters for LNM in EC. The model had a good discrimination ability, especially for normal-sized LNs.

Different imaging techniques for the detection of pelvic lymph nodes metastasis from gynecological malignancies: a systematic review and meta-analysis

OBJECTIVE

This study aimed to evaluate the diagnostic performance of different imaging techniques and the corresponding diagnostic criteria for preoperative detection of pelvic lymph node metastasis from gynecological carcinomas.

METHODS

Six databases were systematically searched for retrieving eligible studies. Study inclusion, data extraction and risk of bias assessment were performed by 2 reviewers independently. STATA 14.0 was used to perform the meta-analysis.

RESULTS

Eighty eligible studies were collected. The pooled sensitivity, specificity, and area under curve (AUC) of CT, MRI and DWI were 47%, 93%, 0.7424; 50%, 95%, 0.8039 and 84%, 95%, 0.9523 respectively. As regards PET, PET-CT and US, the pooled sensitivity, specificity and AUC were 56%, 97%, 0.9592; 68%, 97%, 0.9363 and 71%, 99%, 0.9008 respectively. The summary receiver operating characteristic (SROC) curve indicated that the systematic diagnostic performances of PET, PET-CT, DWI were superior to other imaging modalities.

CONCLUSIONS

The present work demonstrated that DWI, PET, PET-CT were the top-priority consideration of imaging modalities for detecting metastatic pelvic lymph node in gynecological carcinoma. DWI was recommended as the first choice for metastasis exclusion and all the other imaging techniques including CT and MRI were suitable for metastasis conformation. However, for the early stage lymph node malignancy, PET or PET-CT could represent a better choice. More studies exploring the diagnostic efficacy of detailed criteria are required in the future.

Research into the Value of B-Mode Ultrasound, CT and MRI Examinations in the Diagnosis of Preoperative Myometrial Infiltration of Endometrial Cancer and Lymph Node Metastasis

This study is conducted to observe the diagnostic value of B-mode ultrasound, CT and MRI examinations in preoperative myometrial infiltration of endometrial cancer and lymph node metastasis. Retrospectively analyze 50 cases of the patients from Oct. 2010 to Aug. 2013. Before operation all the patients received dilatation & curettage to determine pathological diagnosis and clinical staging. There were 150 cases of patients who received B-mode ultrasound examination, wherein, 93 cases received CT examination and 57 cases received MRI examination as well. In the diagnosis of MIEC the diagnostic indicies of individual MRI examination were higher than that of individual B-mode ultrasound and CT examinations. Consistency of individual MRI examination with pathological diagnosis was significantly higher than that of B-mode and CT examinations. The sensitivity of CT and MRI was significantly higher than that of B-mode ultrasound examination. However, diagnostic indicators of B-mode ultrasound and CT joint examination were higher than B-mode ultrasound examination alone. The consistency of both with pathological diagnosis was significantly increased. B-mode and CT can significantly improve the diagnostic accuracy and has a good consistency with pathological diagnosis, thereby applicable to the clinical diagnosis of preoperative myometrial infiltration of endometrial cancer and lymph node metastasis.

Differential diagnosis between metastatic and non-metastatic lymph nodes using DW-MRI: a meta-analysis of diagnostic accuracy studies

PURPOSES

The purpose of our meta-analysis was to assess the overall diagnostic value of diffusion-weighted magnetic resonance imaging (DW-MRI) in detecting node metastases and investigate whether the apparent diffusion coefficient (ADC) value could be used to discriminate between metastatic and non-metastatic lymph nodes in patients with primary tumors.

MATERIALS AND METHODS

The meta-analysis included a total of 1,748 metastatic and 6,547 non-metastatic lymph nodes from 39 studies, including 8 different tumor types with lymph node metastases.

RESULTS

The pooled sensitivity and specificity of DW-MRI were 0.82 (95 % CI 0.76-0.87) and 0.92 (95 % CI 0.88-0.94), respectively. The positive likelihood ratio (PLR), negative likelihood ratio (NLR), and the area under the curve were 9.8 (95 % CI 6.9-14.0), 0.20 (95 % CI 0.15-0.26) and 0.93 (95 % CI 0.91-0.95), respectively. The probability of 42 % can be viewed as the cutoff pretest probability for DW-MRI to diagnosis lymph node metastases; when the more chance of metastatic increased from 42 % that the pretest probability was estimated, it was more suitable to emphasize on "ruling in," on the contrary, and when the more chance of metastatic decreased from 42 %, it was more suitable to emphasize on "ruling out." Furthermore, the mean ADC value of metastatic lymph nodes was significantly lower than that of non-metastatic (P = 0.001).

CONCLUSIONS

DW-MRI is useful for differentiation between metastatic and non-metastatic lymph nodes. However, DW-MRI has a moderate diagnostic value for physician's decision making when PLR and NLR took into consideration, while a superior ability for nodal metastases confirmation, but an inferior ability for ruling out. In the future, large-scale, high-quality trials are necessary to evaluate, respectively, their clinical value in different tumor types with nodal metastases.