Magnetic resonance imaging for detection of parametrial invasion in cervical cancer: An updated systematic review and meta-analysis of the literature between 2012 and 2016

The value of MRI in quantification of parametrial invasion and association with prognosis in locally advanced cervical cancer: the "PLACE" study

OBJECTIVE

This retrospective observational study aims to evaluate the association between the extent of parametrial invasion (PMI) and disease-free survival (DFS) and cancer-specific survival (CSS) in patients with locally advanced cervical cancer (LACC).

MATERIALS AND METHODS

This study included patients with LACC showing parametrial invasion at Magnetic Resonance Imaging (MRI). They were treated with neoadjuvant chemo-radiotherapy (CT/RT) before undergoing radical hysterectomy. The staging MRIs were reviewed retrospectively. Measurements of maximum PMI (PMImax) and parametrial length were taken bilaterally. After that, PMIratio was calculated by dividing PMImax by parametrial length. Analysis was conducted on homogeneous subsets of patients, grouped based on their pathological lymph nodal evaluation (N- and N+). Correlations between PMImax and PMIratio with DFS and CSS were evaluated in both the N- and N+ groups, employing univariable Cox regression analysis.

RESULTS

Out of 221 patients, 126 (57%) had non-metastatic lymph nodes (N-), while 95 (43%) had metastatic lymph nodes (N+). The median observation period for all these patients was 73 months (95% confidence interval [CI]: 66-77). The 5-year DFS and CSS probability rates were 75% and 85.7%, respectively, for the N- group and 54.3% and 73.6%, respectively, for the N+ group. A higher PMImax (hazard ratio [HR] = 1.09) and PMIratio (HR = 1.04) correlated with worse overall survival in patients in the N- group (p = 0.025 and p = 0.042). These parameters did not show a significant statistical association in the N+ group.

CONCLUSIONS

The degree of PMI evaluated on MRI affects outcome in N- patients with LACC.

CLINICAL RELEVANCE STATEMENT

The degree of MRI parametrial invasion affects disease-free survival and cancer-specific survival in patients with the International Federation of Gynecology and Obstetrics (FIGO) stage IIB cervical cancer. This MRI finding can be easily incorporated into routine clinical practice.

KEY POINTS

• Visual assessment of parametrial invasion on MRI was not significantly associated with prognosis in locally advanced cervical cancer (LACC). • A greater degree of parametrial invasion is associated with poorer disease-free survival and cancer-specific survival in patients with LACC without metastatic lymph node involvement. • The degree of parametrial invasion at MRI has no correlation with prognosis in LACC with metastatic lymph nodes.

ACR Appropriateness Criteria® Pretreatment Evaluation and Follow-Up of Invasive Cancer of the Cervix: 2023 Update

Cervical cancer is a common gynecological malignancy worldwide. Cervical cancer is staged based on the International Federation of Gynecology and Obstetrics (FIGO) classification system, which was revised in 2018 to incorporate radiologic and pathologic data. Imaging plays an important role in pretreatment assessment including initial staging and treatment response assessment of cervical cancer. Accurate determination of tumor size, local extension, and nodal and distant metastases is important for treatment selection and for prognostication. Although local recurrence can be diagnosed by physical examination, imaging plays a critical role in detection and follow-up of local and distant recurrence and subsequent treatment selection. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

The Role of Imaging in Cervical Cancer Staging: ESGO/ESTRO/ESP Guidelines (Update 2023)

Following the European Society of Gynaecological Oncology (ESGO), the European Society for Radiotherapy and Oncology (ESTRO), and the European Society of Pathology (ESP) joint guidelines (2018) for the management of patients with cervical cancer, treatment decisions should be guided by modern imaging techniques. After five years (2023), an update of the ESGO-ESTRO-ESP recommendations was performed, further confirming this statement. Transvaginal/transrectal ultrasound (TRS/TVS) or pelvic magnetic resonance (MRI) enables tumor delineation and precise assessment of its local extent, including the evaluation of the depth of infiltration in the bladder- or rectal wall. Additionally, both techniques have very high specificity to confirm the presence of metastatic pelvic lymph nodes but fail to exclude them due to insufficient sensitivity to detect small-volume metastases, as in any other currently available imaging modality. In early-stage disease (T1a to T2a1, except T1b3) with negative lymph nodes on TVS/TRS or MRI, surgicopathological staging should be performed. In all other situations, contrast-enhanced computed tomography (CECT) or 18F-fluorodeoxyglucose positron emission tomography combined with CT (PET-CT) is recommended to assess extrapelvic spread. This paper aims to review the evidence supporting the implementation of diagnostic imaging with a focus on ultrasound at primary diagnostic workup of cervical cancer.

Clinical value of conventional magnetic resonance imaging combined with diffusion-weighted imaging in predicting pelvic lymph node metastasis of cervical cancer

Background

In cervical cancer (CC), the involvement of pelvis lymph nodes is a crucial factor for patients' outcome. We aimed to investigate the value of conventional magnetic resonance imaging (MRI) combined with diffusion-weighted imaging (DWI) and the apparent diffusion coefficient (ADC) in predicting CC pelvic lymph node metastasis (PLNM).

Methods

This retrospective study included CC patients who received surgical treatments. Surgical pathology results served as the gold standard for investigating the diagnostic performance of conventional MRI combined with DWI. We analyzed the association between tumor ADC and PLNM, as well as other pathological factors. The areas under the receiver operating characteristic curves (AUCs) for ADC in assessing PLNM and pathological factors were evaluated, and optimal cut-off points were obtained.

Results

A total of 261 CC patients were analyzed. PLNM patients had significantly lower tumor ADC (0.829 ± 0.144×10-3mm2/s vs. 1.064 ± 0.345×10-3mm2/s, p<0.0001), than non-PLNM CC. The agreement between conventional MRI combined with DWI and pathological results on PLNM diagnosis was substantial (Kappa=0.7031, p<0.0001), with 76% sensitivity, 94.31% specificity, and 90.8% accuracy. The AUC of tumor ADC was 0.703, and the optimal cut-off was 0.95×10-3 mm2/s. In multivariate analysis model 1, tumor ADC<0.95×10-3mm2/s was significantly associated with PLNM (OR, 2.83; 95%CI, 1.08-7.43; p= 0.0346) after adjusting for age and pathological risk factors. In multivariate analysis model 2, tumor ADC<0.95×10-3mm2/s (OR, 4.00; 95%CI, 1.61-9.89; p=0.0027), age<35 years old (OR, 2.93; 95%CI, 1.04-8.30; p=0.0428), increased tumor diameter on MRI (OR, 2.17; 95%CI, 1.18-3.99; p=0.0128), vaginal vault involvement on MRI (OR, 2; 95%CI, 1.002-3.99; p=0.0494) were independent predictors for PLNM. Tumor ADC<0.95×10-3mm2/s was significantly associated with higher risk of tumor diameter ≥4cm (OR, 2.60; 95%CI, 1.43-4.73; p=0.0017), muscular layer infiltration >1/2 (OR, 5.46; 95%CI, 3.19-9.34; p<0.0001), vaginal vault involvement (OR, 2.25; 95%CI, 1.28-3.96; p=0.0051), and lymphovascular space involvement (OR, 3.81; 95%CI, 2.19-6.63; p<0.0001).

Conclusion

Conventional MRI combined with DWI had a good diagnostic performance in detecting PLNM. The tumor ADC value in PLNM patients was significantly lower than that in non-PLNM patients. Tumor ADC <0.95×10-3mm2/s, age <35 years old, increased tumor diameter on MRI, vaginal vault involvement on MRI were independent predictors for PLNM.

Staging of Cervical Cancer: A Practical Approach Using MRI and FDG PET

This review provides a practical approach to the imaging evaluation of patients with cervical cancer (CC), from initial diagnosis to restaging of recurrence, focusing on MRI and FDG PET. The primary updates to the International Federation of Gynecology and Obstetrics (FIGO) CC staging system, as well as these updates' relevance to clinical management, are discussed. The recent literature investigating the role of MRI and FDG PET in CC staging and image-guided brachytherapy is summarized. The utility of MRI and FDG PET in response assessment and posttreatment surveillance is described. Important findings on MRI and FDG PET that interpreting radiologists should recognize and report are illustrated. The essential elements of structured reports during various phases of CC management are outlined. Special considerations, including the role of imaging in patients desiring fertility-sparing management, differentiation of CC and endometrial cancer, and unusual CC histologies, are also described. Finally, future research directions including PET/MRI, novel PET tracers, and artificial intelligence applications are highlighted.

Deep Learning for Medical Image-Based Cancer Diagnosis

(1) Background: The application of deep learning technology to realize cancer diagnosis based on medical images is one of the research hotspots in the field of artificial intelligence and computer vision. Due to the rapid development of deep learning methods, cancer diagnosis requires very high accuracy and timeliness as well as the inherent particularity and complexity of medical imaging. A comprehensive review of relevant studies is necessary to help readers better understand the current research status and ideas. (2) Methods: Five radiological images, including X-ray, ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI), positron emission computed tomography (PET), and histopathological images, are reviewed in this paper. The basic architecture of deep learning and classical pretrained models are comprehensively reviewed. In particular, advanced neural networks emerging in recent years, including transfer learning, ensemble learning (EL), graph neural network, and vision transformer (ViT), are introduced. Five overfitting prevention methods are summarized: batch normalization, dropout, weight initialization, and data augmentation. The application of deep learning technology in medical image-based cancer analysis is sorted out. (3) Results: Deep learning has achieved great success in medical image-based cancer diagnosis, showing good results in image classification, image reconstruction, image detection, image segmentation, image registration, and image synthesis. However, the lack of high-quality labeled datasets limits the role of deep learning and faces challenges in rare cancer diagnosis, multi-modal image fusion, model explainability, and generalization. (4) Conclusions: There is a need for more public standard databases for cancer. The pre-training model based on deep neural networks has the potential to be improved, and special attention should be paid to the research of multimodal data fusion and supervised paradigm. Technologies such as ViT, ensemble learning, and few-shot learning will bring surprises to cancer diagnosis based on medical images.

Image-Guided Radiotherapy for Gynecologic Malignancies: What the Radiologist Needs to Know

Pelvic imaging is integral to contemporary radiotherapy (RT) management of gynecologic malignancies. For cervical, endometrial, vulvar, and vaginal cancers, three-dimensional imaging modalities aid in tumor staging and RT candidate selection and inform treatment strategy, including RT planning, execution, and posttherapy surveillance. State-of-the-art care routinely incorporates magnetic resonance (MR) imaging, 18F-fluorodeoxyglucose-PET/computed tomography (CT), and CT to guide external beam RT and brachytherapy, allowing the customization of RT plans to maximize patient outcomes and reduce treatment-related toxicities. Follow-up imaging identifies radiation-resistant and recurrent disease as well as short-term and long-term toxicities from RT.

MR Imaging of Gynecologic Tumors: Pearls, Pitfalls, and Tumor Mimics

MR imaging is the modality of choice for the pre-treatment evaluation of patients with gynecologic malignancies, given its excellent soft tissue contrast and multi-planar capability. However, it is not without pitfalls. Challenges can be encountered in the assessment of the infiltration of myometrium, vagina, cervical stroma, and parametria, which are crucial prognostic factors for endometrial and cervical cancers. Other challenges can be encountered in the distinction between solid and non-solid tissue and in the identification of peritoneal carcinomatosis for the sonographically indeterminate adnexal mass.

Diagnostic Accuracy of Magnetic Resonance Imaging in the Pre-Operative Staging of Cervical Cancer Patients Who Underwent Neoadjuvant Treatment: A Clinical–Surgical–Pathologic Comparison

Magnetic resonance imaging (MRI) has been proven to ensure high diagnostic accuracy in the identification of vaginal, parametrial, and lymph node involvement in patients affected by cervical cancer (CC), thus playing a crucial role in the preoperative staging of the disease. This study aims to compare the accuracy of MRI for the preoperative staging of patients with CC who underwent neoadjuvant treatment (NAT) or direct surgery. Retrospective data analysis of 126 patients with primary CC International Federation of Gynecology and Obstetrics stage IB3-IIB who underwent NAT before radical surgery (NAT group = 94) or received surgical treatment alone (control arm = 32) was prospectively performed. All enrolled patients were clinically assessed with both a pelvic examination and MRI before surgical treatment. Data from the clinical examination were compared with the histopathological findings to assess the accuracy of MRI for staging purposes after NAT or before direct surgery. MRI showed an overall accuracy of 46.1%, proving it to be not superior to pelvic and physical examination. The overall MRI accuracy for the evaluation of parametrial, vaginal, and lymph node status was 65.8%, 79.4%, and 79.4%, respectively. In the NAT group, the accuracy for the detection of parametrial, lymph node, and vaginal involvement was lower than the control group; however, the difference was not significant (p ≥ 0.05). The overall accuracy of MRI for the preoperative staging of CC after NAT is shown to be not unsatisfactory. The limits of MRI staging are especially evident when dealing with pre-treated patients.

MR Imaging in Cervical Cancer

Cervical cancer remains a significant contributor to morbidity and mortality for women globally despite medical advances in preventative medicine and treatment. The 2018 Internal Federation of Gynecology and Obstetrics committee modified their original 2009 staging scheme to incorporate advanced imaging modalities, where available, to increase the accuracy of staging and to guide evolving treatments. Having a robust understanding of the newest staging iteration, its consequences on treatment pathways, and common imaging pitfalls will aid the radiologist in generating valuable and practical reports to optimize treatment strategies.

PET-MRI for evaluation of response to radiochemotherapy in patients with locally advanced cervical cancer

OBJECTIVE

We aimed to analyze the diagnostic test accuracy of positron emission tomography and a magnetic resonance imaging scan (PET-MRI) fusion in evaluating tumor response after radiochemotherapy in patients with locally advanced cervical cancer.

METHODS

Patients treated at two institutes between January 2008 and December 2016 were studied retrospectively. Re-evaluation by positron emission tomography (PET) and magnetic resonance imaging (MRI) was performed in a non-concurrent way 4-8 weeks after treatment. A nuclear medicine doctor and a radiologist (subsequently referred as "radiologists"), both experts in gynecological oncology, re-examined the post-treatment MRI and positron emission tomography-computed tomography (PET-CT) separately, and then performed a fusion of these examinations. In this study we describe this "a posteriori fusion methodology", with two levels, enabling limitation of anatomical shifts. The gold standard was anatomical pathology analysis of the surgical specimen, since all patients underwent surgery following this radiological re-evaluation. The radiologists' degree of certainty in their diagnoses, and the impact of fusion on their diagnostic confidence were assessed by the radiologists, using two Likert judgment scales. They also adjudicated on possible changes of interpretation after the fusion.

RESULTS

Thirty-one patients were included. The PET-MRI fusion has a sensitivity of 79% and a specificity of 90%. The positive predictive value (PPV) was 94%, and the negative predictive value (NPV) was 69%. In 45% of cases (n=13), radiologists reported an improvement in their degree of certainty in their diagnosis using a Likert judgment scale, due to inspecting the PET and MRI fused. A change in interpretation of tumor response was observed using a Likert judgment scale in 31% of cases.

CONCLUSION

PET-MRI fusion improves the radiologist's own diagnostic confidence in assessing response to concurrent radiochemotherapy in locally advanced cervical cancer. More studies using a latest generation hybrid system will be necessary to further compare to MRI and PET-CT.

Diagnostic Value of Diffusion-Weighted Imaging with Background Body Signal Suppression (DWIBS) for the Pre-Therapeutic Loco-Regional Staging of Cervical Cancer: A Feasibility and Interobserver Reliability Study

(1) Background: cervical cancer is one of the leading causes of cancer-related deaths and the fourth most common cancer among women worldwide. Magnetic resonance imaging (MRI) is the modality of choice for loco-regional staging of cervical cancer in the primary diagnostic workup beginning with at least stage IB. (2) Methods: we retrospectively analyzed 16 patients with histopathological proven cervical cancer (FIGO IB1−IVA) for the diagnostic accuracy of standard MRI and standard MRI with diffusion-weighted imaging with background body signal suppression (DWIBS) for the correct pre-therapeutic assessment of the definite FIGO category. (3) Results: In 7 out of 32 readings (22%), DWIBS improved diagnostic accuracy. With DWIBS, four (13%) additional readings were assigned the correct major (I−IV) FIGO stages pre-therapeutically. Interobserver reliability of DWIBS was weakest for parametrial infiltration (k = 0.43; CI-95% 0.00−1.00) and perfect for tumor size <2 cm, infiltration of the vaginal lower third, infiltration of adjacent organs and loco-regional nodal metastases (k = 1.000; CI-95% 1.00−1.00). (4) Conclusions: the pre-therapeutic staging of cervical cancer has a high diagnostic accuracy and interobserver reliability when using standard MRI but can be further optimized with the addition of DWIBS sequences when reporting is performed by an experienced radiologist.

Post treatment imaging in patients with local advanced cervical carcinoma

Cervical cancer (CC) is the fourth leading cause of death in women worldwide and despite the introduction of screening programs about 30% of patients presents advanced disease at diagnosis and 30-50% of them relapse in the first 5-years after treatment. According to FIGO staging system 2018, stage IB3-IVA are classified as locally advanced cervical cancer (LACC); its correct therapeutic choice remains still controversial and includes neoadjuvant chemo-radiotherapy, external beam radiotherapy, brachytherapy, hysterectomy or a combination of these modalities. In this review we focus on the most appropriated therapeutic options for LACC and imaging protocols used for its correct follow-up. We explore the imaging findings after radiotherapy and surgery and discuss the role of imaging in evaluating the response rate to treatment, selecting patients for salvage surgery and evaluating recurrence of disease. We also introduce and evaluate the advances of the emerging imaging techniques mainly represented by spectroscopy, PET-MRI, and radiomics which have improved diagnostic accuracy and are approaching to future direction.

Can MRI Be Used as a Sole Diagnostic Modality in Determining Clinical Stage in Cervical Cancer?

OBJECTIVE

The objective of this study was to compare staging by MRI to clinical staging in patients with cervical cancer and to determine the histological accuracy of staging by MRI and examination under anesthesia (EUA) in early stage disease.

METHODS

This was a retrospective cohort study of patients diagnosed with cervical cancer between 2010 and 2020 at the Radboud University Medical Centre, the Netherlands. Pretreatment stage (FIGO 2009) by MRI was compared with staging by EUA. Diagnostic accuracy in terms of sensitivity, specificity, positive, and negative predictive value was calculated for MRI and EUA in patients undergoing surgery (early stage disease) with histological results as a reference standard.

RESULTS

A total of 358 patients were included in the study and MRI-based stage differed from EUA stage in 30.7%. In 12.3% this meant a discrepancy in treatment assignment between MRI and EUA. Diagnostic accuracy of MRI in terms of sensitivity and specificity for detecting early stage disease was comparable to EUA in surgical patients. Further analyses showed that premenopausal status, early stage disease and a tumor diameter of <2 cm were associated with improved comparability of MRI and EUA (98%).

CONCLUSION

There is still a large discrepancy between MRI and EUA. In patients with suspected early stage disease, diagnostic accuracy of MRI is similar to EUA, especially for premenopausal women with early stage disease and a tumor diameter of <2 cm.

Can the combination of DWI and T2WI radiomics improve the diagnostic efficiency of cervical squamous cell carcinoma?

BACKGROUND

To investigate the value of MRI multi-sequence imaging model in differentiation of cervical squamous cell carcinoma (CSCC).

METHODS

A total of 104 CSCC patients confirmed with pathology were retrospectively enrolled. All patients underwent conventional MRI examination before treatment. The lesions were segmented using ITK-SNAP software manually and radiomics features were extracted by Artificial Intelligence Kit (AK) software. 396 tumor texture features were obtained and then the mRMR and Lasso algorithms were used to reduce the feature dimension. Three models including T2WI model, DWI model and Joint model (combined TWI and DWI) were constructed in training group and evaluated in validation group. and the receiver operator characteristics and calibration curve were used to evaluate the model performance.

RESULTS

The Joint model and T2WI model both showed a better diagnostic efficacy than single DWI model in differentiation of CSCC in training group (Joint model: AUC = 0.841; T2WI model: AUC = 0.804; DWI model: AUC = 0.732) and validation group (Joint model: AUC = 0.822; T2WI model: AUC = 0.791; DWI model: AUC = 0.724). But there was no statistical difference between Joint model and T2WI model by Delong test(P > 0.05).

CONCLUSIONS

The study suggested that the conventional T2WI sequence may be more suitable for prognosis evaluation of CSCC, which can provide a potential tool to facilitate the differential diagnosis of low-differentiation and high-differentiation CSCC.

Contemporary image-guided cervical cancer brachytherapy: Consensus imaging recommendations from the Society of Abdominal Radiology and the American Brachytherapy Society

PURPOSE

To present recommendations for the use of imaging for evaluation and procedural guidance of brachytherapy for cervical cancer patients.

METHODS

An expert panel comprised of members of the Society of Abdominal Radiology Uterine and Ovarian Cancer Disease Focused Panel and the American Brachytherapy Society jointly assessed the existing literature and provide data-driven guidance on imaging protocol development, interpretation, and reporting.

RESULTS

Image-guidance during applicator implantation reduces rates of uterine perforation by the tandem. Postimplant images may be acquired with radiography, computed tomography (CT), or magnetic resonance imaging (MRI), and CT or MRI are preferred due to a decrease in severe complications. Pre-brachytherapy T2-weighted MRI may be used as a reference for contouring the high-risk clinical target volume (HR-CTV) when CT is used for treatment planning. Reference CT and MRI protocols are provided for reference.

CONCLUSIONS

Image-guided brachytherapy in locally advanced cervical cancer is essential for optimal patient management. Various imaging modalities, including orthogonal radiographs, ultrasound, computed tomography, and magnetic resonance imaging, remain integral to the successful execution of image-guided brachytherapy.

Interobserver agreement and prognostic impact for MRI-based 2018 FIGO staging parameters in uterine cervical cancer

OBJECTIVES

To evaluate the interobserver agreement for MRI-based 2018 International Federation of Gynecology and Obstetrics (FIGO) staging parameters in patients with cervical cancer and assess the prognostic value of these MRI parameters in relation to other clinicopathological markers.

METHODS

This retrospective study included 416 women with histologically confirmed cervical cancer who underwent pretreatment pelvic MRI from May 2002 to December 2017. Three radiologists independently recorded MRI-derived staging parameters incorporated in the 2018 FIGO staging system. Kappa coefficients (κ) for interobserver agreement were calculated. The predictive and prognostic values of the MRI parameters were explored using ROC analyses and Kaplan-Meier with log-rank tests, and analyzed in relation to clinicopathological patient characteristics.

RESULTS

Overall agreement was substantial for the staging parameters: tumor size > 2 cm (κ = 0.80), tumor size > 4 cm (κ = 0.76), tumor size categories (≤ 2 cm; > 2 and ≤ 4 cm; > 4 cm) (κ = 0.78), parametrial invasion (κ = 0.63), vaginal invasion (κ = 0.61), and enlarged lymph nodes (κ = 0.63). Higher MRI-derived tumor size category (≤ 2 cm; > 2 and ≤ 4 cm; > 4 cm) was associated with a stepwise reduction in survival (p ≤ 0.001 for all). Tumor size > 4 cm and parametrial invasion at MRI were associated with aggressive clinicopathological features, and the incorporation of these MRI-based staging parameters improved risk stratification when compared to corresponding clinical assessments alone.

CONCLUSION

The interobserver agreement for central MRI-derived 2018 FIGO staging parameters was substantial. MRI improved the identification of patients with aggressive clinicopathological features and poor survival, demonstrating the potential impact of MRI enabling better prognostication and treatment tailoring in cervical cancer.

KEY POINTS

• The overall interobserver agreement was substantial (κ values 0.61-0.80) for central MRI staging parameters in the 2018 FIGO system. • Higher MRI-derived tumor size category was linked to a stepwise reduction in survival (p ≤ 0.001 for all). • MRI-derived tumor size > 4 cm and parametrial invasion were associated with aggressive clinicopathological features, and the incorporation of these MRI-derived staging parameters improved risk stratification when compared to clinical assessments alone.

ACR Appropriateness Criteria® Staging and Follow-up of Primary Vaginal Cancer

Primary vaginal cancer is rare, comprising 1% to 2% of gynecologic malignancies and 20% of all malignancies involving the vagina. More frequently, the vagina is involved secondarily by direct invasion from malignancies originating in adjacent organs or by metastases from other pelvic or extrapelvic primary malignancies. Data on the use of imaging in vaginal cancer are sparse. Insights are derived from the study of imaging in cervical cancer and have reasonable generalizability to vaginal cancer due to similar tumor biology. Given the trend toward definitive chemoradiation for both cancers in all but early stage lesions, principles of postchemoradiation tumor response evaluation are largely analogous. Accordingly, many of the recommendations outlined here are informed by principles translated from the literature on cervical cancer. For pretreatment assessment of local tumor burden and in the case of recurrent vaginal cancer, MRI is the preferred imaging modality. PET/CT has demonstrated utility for the detection of nodal metastatic and unexpected distant metastatic disease. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

[Uterine Cervical Cancer: Emphasis on Revised FIGO Staging 2018 and MRI]

Uterine cervical cancer is a common gynecological cancer prevalent in Korea. Early detection, precise diagnosis, and appropriate treatment can affect its prognosis. Imaging approaches play an important role in staging, treatment planning, and follow-up. MRI specifically provides the advantage of assessing tumor size and disease severity with high soft tissue contrast. The revised version of the International Federation of Gynecology and Obstetrics (FIGO) staging system has been introduced in 2018, which incorporates subdivided primary tumor size and lymph node metastasis. In this review, the staging of uterine cervical cancer based on previous studies, the recently revised FIGO staging, and various post-treatment images are primarily described using MRI.

Diagnostic Accuracy of Magnetic Resonance Imaging for International Federation of Gynecology and Obstetrics 2018 IB to IIB Cervical Cancer Staging: Comparison Among Magnetic Resonance Sequences and Pathologies

OBJECTIVE

This study aimed to investigate the most accurate magnetic resonance (MR) sequence for tumor detection, maximal tumor diameter, and parametrial invasion compared with histopathologic diagnoses.

METHODS

Fifty-one patients with International Federation of Gynecology and Obstetrics 2018 IB1 to IIB cervical cancer underwent preoperative MR imaging and surgical resection. Two radiologists independently evaluated the tumor detection, parametrial invasion, and tumor size in each of T2-weighted image, diffusion-weighted image, and contrast-enhanced T1-weighted image. Results obtained for squamous cell carcinoma (SCC) and adenocarcinoma were also compared.

RESULTS

Neither the tumor detection rate nor parametrial invasion was found to be significantly different among sequences. Tumor size assessment using MR imaging with pathology showed good correlation: r = 0.63-0.72. The adenocarcinoma size tended to be more underestimated than SCC in comparison with the pathologic specimen.

CONCLUSIONS

Cervical cancer staging by MR images showed no significant difference among T2-weighted image, diffusion-weighted image, and contrast-enhanced T1-weighted image. Adenocarcinoma was prone to be measured as smaller than the pathologic specimen compared with SCC.

The Importance of Clinical Examination under General Anesthesia: Improving Parametrial Assessment in Cervical Cancer Patients

Simple Summary

In most cases, the treatment strategy (radiation or surgery) in cervical cancer patients depends on whether the parametrium shows tumor involvement. Traditionally, clinical pelvic examination under general anesthesia (EUA) has been used to determine whether tumor spread into the parametrium is present. During the recent decade, however, magnetic resonance imaging (MRI) has been increasingly used to determine whether parametrial tumor extension is present, and several studies have indicated that MRI might be superior to EUA. In this study, we demonstrate that EUA still plays an important role in pre-therapeutic evaluation of cervical cancer patients, and that display of MR images in the operating room (augmented EUA) achieves superior results in predicting parametrial tumor spread when comparted to MRI alone, especially in larger tumors. Best predictive results were observed in cases when radiologists and gynecological oncologists agreed on parametrial status, highlighting the importance of interdisciplinary patient assessment.

Abstract

Background: Parametrial tumor involvement is an important prognostic factor in cervical cancer and is used to guide management. Here, we investigate the diagnostic value of clinical examination under general anesthesia (EUA) and magnetic resonance imaging (MRI) in determining parametrial tumor spread. Methods: Post-operative pathological findings of 400 patients with primary cervical cancer were compared to the respective MRI data and the results from EUA. The gynecological oncologist had access to the MR images during clinical assessment (augmented EUA, aEUA). Results: Pathologically proven parametrial tumor invasion was present in 165 (41%) patients. aEUA exhibited a higher accuracy than MRI alone (83% vs. 76%; McNemar’s odds ratio [OR] = 2.0, 95%CI 1.25–3.27, p = 0.003). Although accuracy was not affected by tumor size in aEUA, MRI was associated with a lower accuracy in tumors ≥2.5 cm (OR for a correct diagnosis compared to smaller tumors 0.22, p < 0.001). There was also a decrease in specificity when evaluating parametrial invasion by MRI in tumors ≥2.5 cm in diameter (p < 0.0001) compared to smaller tumors (< 2.5 cm). Body mass index had no influence on performance of either method. Conclusions: aEUA has the potential to increase the diagnostic accuracy of MRI in determining parametrial tumor involvement in cervical cancer patients.

Diagnostic Value of Combined Intravoxel Incoherent Motion Diffusion-Weighted Magnetic Resonance Imaging with Diffusion Tensor Imaging in Predicting Parametrial Infiltration in Cervical Cancer

Objective

This study sought to determine the diagnostic value of combined intravoxel incoherent motion (IVIM) diffusion-weighted magnetic resonance imaging (MRI) with diffusion tensor imaging (DTI) in predicting parametrial infiltration (PMI) in patients with cervical cancer.

Materials and Methods

We enrolled 65 patients with cervical cancer confirmed by radical hysterectomy (25 PMI-negative and 40 PMI-positive) who underwent IVIM and DTI pretreatment. The parameters of IVIM (ADC, D, D  ^∗ , and f) and DTI (average diffusion coefficient (DCavg) and fractional anisotropy (FA)) were recorded by two observers. All parameter differences were tested, and the receiver operating characteristic (ROC) curves were generated to estimate the diagnostic performance of significant metrics and their combinations.

Results

Compared to the PMI-negative group, the PMI-positive group had significantly lower D (0.632 ± 0.017 vs. 0.773 ± 0.024, p < 0.001) and lower FA (0.073 ± 0.002 vs. 0.085 ± 0.003, p=0.003). The area under the ROC curve (AUC) of D and FA was 0.801 and 0.726, respectively, and the combination of D and FA improved the AUC to 0.931, with a sensitivity and specificity of 80.0% and 97.5%, respectively.

Conclusion

D and FA values could be used to help diagnose PMI in patients with cervical cancer. The combination of IVIM and DTI was more valuable than either option alone.

Implications of the new FIGO staging and the role of imaging in cervical cancer

International Federation of Gynecology and Obstetrics (FIGO) staging, which is the fundamentally important cancer staging system for cervical cancer, has changed in 2018. New FIGO staging includes considerable progress in the incorporation of imaging findings for tumour size measurement and evaluating lymph node (LN) metastasis in addition to tumour extent evaluation. MRI with high spatial resolution is expected for tumour size measurements and the high accuracy of positron emmision tomography/CT for LN evaluation. The purpose of this review is firstly review the diagnostic ability of each imaging modality with the clinical background of those two factors newly added and the current state for LN evaluation. Secondly, we overview the fundamental imaging findings with characteristics of modalities and sequences in MRI for accurate diagnosis depending on the focus to be evaluated and for early detection of recurrent tumour. In addition, the role of images in treatment response and prognosis prediction is given with the development of recent technique of image analysis including radiomics and deep learning.

Staging, recurrence and follow-up of uterine cervical cancer using MRI: Updated Guidelines of the European Society of Urogenital Radiology after revised FIGO staging 2018

OBJECTIVES

The recommendations cover indications for MRI examination including acquisition planes, patient preparation, imaging protocol including multi-parametric approaches such as diffusion-weighted imaging (DWI-MR),  dynamic contrast-enhanced imaging (DCE-MR) and standardised reporting. The document also underscores the value of whole-body 18-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG-PET/CT) and highlights potential future methods.

METHODS

In 2019, the ESUR female pelvic imaging working group reviewed the revised 2018 FIGO staging system, the up-to-date clinical management guidelines, and the recent imaging literature. The RAND-UCLA Appropriateness Method (RAM) was followed to develop the current ESUR consensus guidelines following methodological steps: literature research, questionnaire developments, panel selection, survey, data extraction and analysis.

RESULTS

The updated ESUR guidelines are recommendations based on ≥ 80% consensus among experts. If ≥ 80% agreement was not reached, the action was indicated as optional.

CONCLUSIONS

The present ESUR guidelines focus on the main role of MRI in the initial staging, response monitoring and evaluation of disease recurrence. Whole-body FDG-PET plays an important role in the detection of lymph nodes (LNs) and distant metastases.

KEY POINTS

• T2WI and DWI-MR are now recommended for initial staging, monitoring of response and evaluation of recurrence. • DCE-MR is optional; its primary role remains in the research setting. • T2WI, DWI-MRI and whole-body FDG-PET/CT enable comprehensive assessment of treatment response and recurrence.

Diagnostic Accuracy of 18F-FDG-PET/CT and MRI in Predicting the Tumor Response in Locally Advanced Cervical Carcinoma Treated by Chemoradiotherapy: A Meta-Analysis

Objective

The aim of this meta-analysis was to compare the diagnostic accuracy of 18F-FDG-PET/CT and MRI in predicting the tumor response in locally advanced cervical carcinoma (LACC) treated by chemoradiotherapy (CRT).

Method

This meta-analysis has been performed according to PRISMA guidelines. Systematic searches were conducted using PubMed and Embase databases for articles published from January 1, 2010, to January 1, 2020. By using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool, the reviewers assessed the methodological quality scores of the selected studies. We analyzed the sensitivity, specificity, and accuracy of two diagnostic methods using Meta-DiSc 1.4 and Stata 15.

Results

An overall of 15 studies including 1132 patients were included. Sensitivities of PET/CT and MRI were 83.5% and 82.7%, while the corresponding rates for specificities were 77.8% and 68.4%, respectively. The DOR, PLR, and NLR for MRI were 15.140, 2.92, and 22.6. PET/CT had a DOR of 25.21. The PLR and NLR for PET/CT were 4.13 and 0.215, respectively. The diagnostic sensitivity and specificity of PET/CT for the detection of residual tumor were 86% and 95%, respectively. The corresponding rates for MRI were 73% and 96%, respectively. The diagnostic sensitivity and specificity of PET/CT for the detection of tumor metastases were 97% and 99%, while the corresponding rates for MRI were 31% and 98%, respectively.

Conclusion

18F-FDG PET/CT seemed to have a better overall diagnostic accuracy in the evaluation of treatment response to chemoradiotherapy in LACC patients. MRI showed a really poor sensitivity in the detection of metastases, and PET/CT performed significantly better. However, the difference between these two methods in the detection of residual disease was not significant. More studies are needed to be conducted in order to approve that 18F-FDG PET/CT can be a standard option to assess the treatment response.

Diagnostic Value of 18F-FDG PET/MRI for Revised 2018 FIGO Staging in Patients with Cervical Cancer

Purpose: To evaluate the diagnostic potential of PET/MRI with ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) in cervical cancer based on the revised 2018 International Federation of Gynecology and Obstetrics (FIGO) staging system. Materials and Methods: Seventy-two patients with biopsy-proven primary cervical cancer underwent pretreatment ¹⁸F-FDG PET/MRI, CT, and pelvic MRI. The diagnostic performance of ¹⁸F-FDG PET/MRI and MRI for assessing extent of the primary tumor and ¹⁸F-FDG PET/MRI and CT for assessing nodal and distant metastases was evaluated by two experienced readers. Histopathological and follow-up imaging results were used as the gold standard. McNemar test was employed for statistical analysis. Results: Accuracy for the invasion of vagina, parametrium, side wall, and adjacent organs was 97.2%, 93.1%, 97.2%, and 100% for ¹⁸F-FDG PET/MRI; and 97.2%, 91.7%, 97.2%, and 100% for pelvic MRI, respectively (p > 0.05). Patient-based accuracy for metastasis to pelvic and paraaortic lymph nodes and distant organs was 95.8%, 98.6%, and 100% for ¹⁸F-FDG PET/MRI; and 83.3%, 95.8%, and 97.2% for CT, respectively; metastasis to pelvic lymph nodes was statistically significant (p < 0.01). Lesion-based sensitivity, specificity, and accuracy for lymph nodes were 83.3%, 95.9%, and 94.8% for ¹⁸F-FDG PET/MRI; and 29.2%, 98.9% and 93.1% for CT, respectively; sensitivity was statistically significant (p < 0.001). After excluding patients diagnosed by conization, accuracy for revised FIGO staging 2018 was significantly better for ¹⁸F-FDG PET/MRI (82.1%) than for CT and MRI (60.7%) (p < 0.01). Conclusions: ¹⁸F-FDG PET/MRI offers higher diagnostic value for revised 2018 FIGO staging, suggesting that ¹⁸F-FDG PET/MRI might provide an optimal diagnostic strategy for preoperative staging.

Diagnostic efficiency of whole-body 18F-FDG PET/MRI, MRI alone, and SUV and ADC values in staging of primary uterine cervical cancer

Background

The use of PET/MRI for gynecological cancers is emerging. The purpose of this study was to assess the additional diagnostic value of PET over MRI alone in local and whole-body staging of cervical cancer, and to evaluate the benefit of standardized uptake value (SUV) and apparent diffusion coefficient (ADC) in staging.

Methods

Patients with histopathologically-proven cervical cancer and whole-body ¹⁸F-FDG PET/MRI obtained before definitive treatment were retrospectively registered. Local tumor spread, nodal involvement, and distant metastases were evaluated using PET/MRI or MRI dataset alone. Histopathology or clinical consensus with follow-up imaging were used as reference standard. Tumor SUVmax and ADC were measured and SUVmax/ADC ratio calculated. Area under the curve (AUC) was determined to predict diagnostic performance and Mann-Whitney U test was applied for group comparisons.

Results

In total, 33 patients who underwent surgery (n = 23) or first-line chemoradiation (n = 10) were included. PET/MRI resulted in higher AUC compared with MRI alone in detecting parametrial (0.89 versus 0.73), vaginal (0.85 versus 0.74), and deep cervical stromal invasion (0.96 versus 0.74), respectively. PET/MRI had higher diagnostic confidence than MRI in identifying patients with radical cone biopsy and no residual at hysterectomy (sensitivity 89% versus 44%). PET/MRI and MRI showed equal AUC for pelvic nodal staging (both 0.73), whereas AUC for distant metastases was higher using PET/MRI (0.80 versus 0.67). Tumor SUVmax/ADC ratio, but not SUVmax or ADC alone, was significantly higher in the presence of metastatic pelvic lymph nodes (P < 0.05).

Conclusions

PET/MRI shows higher accuracy than MRI alone for determining local tumor spread and distant metastasis emphasizing the added value of PET over MRI alone in staging of cervical cancer. Tumor SUVmax/ADC ratio may predict pelvic nodal involvement.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40644-020-00372-5.

Gynecologic Malignancies

Gynecologic malignancies are among the most prevalent cancers affecting women worldwide, but they are heterogeneous diseases with varying risk factors, management paradigms, and outcomes. Gynecologic cancers mediated by human papillomavirus (HPV) are preventable and curable with early detection and treatment. Dramatic reductions in cervical cancer incidence and mortality have been achieved through cancer screening and HPV vaccination. Radiotherapy plays a central role in the management of gynecologic malignancies. For some cancers, radiotherapy alone can be curative. More often, radiotherapy is used in conjunction with surgery and systemic therapy to improve locoregional control and extend overall survival. This chapter reviews recent advances in radiotherapeutic management of gynecologic malignancies.

Multimodality Imaging of Uterine Cervical Malignancies

OBJECTIVE. In this article, we provide an updated review on the role of imaging in initial staging, treatment monitoring, and follow-up of cervical cancer with a focus on the role of MRI and FDG PET/CT. In addition, the 2018 International Federation of Gynecology and Obstetrics staging system and its implication on management of cervical cancer are explored. CONCLUSION. Imaging plays a major role in treatment planning and as a prognostic indicator in patients with cervical cancer. MRI and PET/CT have complementary roles: MRI is essential for the local staging of the primary tumor, and PET/CT is the most useful modality for detecting regional nodal and distant metastases.

Diagnostic performance of conventional and advanced imaging modalities for assessing newly diagnosed cervical cancer: systematic review and meta-analysis

OBJECTIVES

To review the diagnostic performance of contemporary imaging modalities for determining local disease extent and nodal metastasis in patients with newly diagnosed cervical cancer.

METHODS

Pubmed and Embase databases were searched for studies published from 2000 to 2019 that used ultrasound (US), CT, MRI, and/or PET for evaluating various aspects of local extent and nodal metastasis in patients with newly diagnosed cervical cancer. Sensitivities and specificities from the studies were meta-analytically pooled using bivariate and hierarchical modeling.

RESULTS

Of 1311 studies identified in the search, 115 studies with 13,999 patients were included. MRI was the most extensively studied modality (MRI, CT, US, and PET were evaluated in 78, 12, 9, and 43 studies, respectively). Pooled sensitivities and specificities of MRI for assessing all aspects of local extent ranged between 0.71-0.88 and 0.86-0.95, respectively. In assessing parametrial invasion (PMI), US demonstrated pooled sensitivity and specificity of 0.67 and 0.94, respectively-performance levels comparable with those found for MRI. MRI, CT, and PET performed comparably for assessing nodal metastasis, with low sensitivity (0.29-0.69) but high specificity (0.88-0.98), even when stratified to anatomical location (pelvic or paraaortic) and level of analysis (per patient vs. per site).

CONCLUSIONS

MRI is the method of choice for assessing any aspect of local extent, but where not available, US could be of value, particularly for assessing PMI. CT, MRI, and PET all have high specificity but poor sensitivity for the detection of lymph node metastases.

KEY POINTS

• Magnetic resonance imaging is the method of choice for assessing local extent. • Ultrasound may be helpful in determining parametrial invasion, especially in lower-resourced countries. • Computed tomography, magnetic resonance imaging, and positron emission tomography perform similarly for assessing lymph node metastasis, with high specificity but low sensitivity.

Diagnostic Performance of Vesical Imaging Reporting and Data System for the Prediction of Muscle-invasive Bladder Cancer: A Systematic Review and Meta-analysis

CONTEXT

A noninvasive multiparametric magnetic resonance imaging (MRI)-based scoring system for predicting muscle-invasive bladder cancer (MIBC), the "Vesical Imaging Reporting and Data System" (VI-RADS), was recently developed by an international multidisciplinary panel. Since then, a few studies evaluating the value of VI-RADS for predicting MIBC have been published.

OBJECTIVE

To review the diagnostic performance of VI-RADS for the prediction of MIBC.

EVIDENCE ACQUISITION

PubMed and EMBASE databases were searched up to November 10, 2019. We included diagnostic accuracy studies using VI-RADS to predict MIBC using cystectomy or transurethral resection as the reference standard. Methodological quality was evaluated with Quality Assessment of Diagnostic Accuracy Studies-2. Sensitivity and specificity were pooled and plotted using hierarchical summary receiver operating characteristics (HSROC) modeling. Meta-regression analyses were done to explore heterogeneity.

EVIDENCE SYNTHESIS

Six studies (1770 patients) were included. Pooled sensitivity and specificity were 0.83 (95% confidence interval [CI] 0.70-0.90) and 0.90 (95% CI 0.83-0.95), and the area under the HSROC curve was 0.94 (95% CI 0.91-0.95). Heterogeneity was present among the studies (Q = 29.442, p <  0.01; I² = 87.93%, and 90.99% for sensitivity and specificity). Meta-regression analyses showed that the number of patients (>205 vs ≤205), magnetic field strength (3 vs 1.5 T), T2-weighted image slice thickness (3 vs 4 mm), and VI-RADS cutoff score (≥3 vs ≥4) were significant factors affecting heterogeneity (p ≤  0.03).

CONCLUSIONS

VI-RADS shows good sensitivity and specificity for determining MIBC. Technical factors associated with MRI acquisition and cutoff scores need to be taken into consideration as they may affect performance.

PATIENT SUMMARY

A recently established noninvasive magnetic resonance imaging-based scoring system shows good diagnostic performance in detecting muscle-invasive bladder cancer.

Preoperative prediction of parametrial invasion in early-stage cervical cancer with MRI-based radiomics nomogram

PURPOSE

To develop and identify a MRI-based radiomics nomogram for the preoperative prediction of parametrial invasion (PMI) in patients with early-stage cervical cancer (ECC).

MATERIALS AND METHODS

All 137 patients with ECC (FIGO stages IB-IIA) underwent T2WI and DWI scans before radical hysterectomy surgery. The radiomics signatures were calculated with the radiomics features which were extracted from T2WI and DWI and selected by the least absolute shrinkage and selection operation regression. The support vector machine (SVM) models were built using radiomics signatures derived from T2WI and joint T2WI and DWI respectively to evaluate the performance of radiomics signatures for distinguishing patients with PMI. A radiomics nomogram was drawn based on the radiomics signatures with a better performance, patient's age, and pathological grade; its discrimination and calibration performances were estimated.

RESULTS

For T2WI and joint T2WI and DWI, the radiomics signatures yielded an AUC of 0.797 (95% CI, 0.682-0.911) vs 0.946 (95% CI, 0.899-0.994), and 0.780 (95% CI, 0.641-0.920) vs 0.921 (95% CI, 0.832-1) respectively in the primary and validation cohorts. The radiomics nomogram, integrating the radiomics signatures from joint T2WI and DWI, patient's age, and pathological grade, showed excellent discrimination, with C-index values of 0.969 (95% CI, 0.933-1) and 0.941 (95% CI, 0.868-1) in the primary and validation cohorts, respectively. The calibration curve showed a good agreement.

CONCLUSIONS

The radiomics nomogram performed well for the preoperative prediction of PMI in patients with ECC and may be used as a supplementary tool to provide individualized treatment plans for patients with ECC.

KEY POINTS

• No previously reported study that has utilized radiomics nomogram to preoperatively predict PMI for patients with ECC. • Radiomics model involves radiomics features extracted from joint T2WI and DWI which characterize the heterogeneity between tumors in patients with ECC. • Radiomics nomogram can assist clinicians with individualized treatment decision-making for patients with ECC.

Diagnostic Performance of MRI for Assessing Parametrial Invasion in Cervical Cancer: A Head-to-Head Comparison between Oblique and True Axial T2-Weighted Images

OBJECTIVE

To directly compare the diagnostic performance of true and oblique axial T2-weighted imaging (T2WI) for assessing parametrial invasion (PMI) in cervical cancer.

MATERIALS AND METHODS

This retrospective study included 71 women with treatment-naive cervical cancer who underwent MRI that included both oblique and true axial T2WI, followed by radical hysterectomy. Two blinded radiologists (Radiologist 1 and Radiologist 2) independently assessed the presence of PMI on both sequences using a 5-point Likert scale. Receiver operating characteristic (ROC) curve analysis was performed, with a subgroup analysis for tumors sized > 2.5 cm and ≤ 2.5 cm in diameter. Inter-reader agreement was assessed with kappa (k) statistics.

RESULTS

At hysterectomy, 15 patients (21.1%) had PMI. For Radiologist 1, the area under the ROC curve (AUC) was greater for oblique axial than for true axial T2WI {0.941 (95% confidence interval [CI] = 0.858-0.983) vs. 0.917 (95% CI = 0.827-0.969), p = 0.027}. The difference was not significant for Radiologist 2 (0.879 [95% CI = 0.779-0.944] vs. 0.827 [95% CI = 0.719-0.906], p = 0.153). For tumors > 2.5 cm, AUC was greater with oblique than with true axial T2WI (0.906 vs. 0.860, p = 0.046 for Radiologist 1 and 0.839 vs. 0.765, p = 0.086 for Radiologist 2). Agreement between the radiologists was almost perfect for oblique axial T2WI (k = 0.810) and was substantial for true axial T2WI (k = 0.704).

CONCLUSION

Oblique axial T2WI potentially provides greater diagnostic performance than true axial T2WI for determining PMI, particularly for tumors > 2.5 cm. The inter-reader agreement was greater with oblique axial T2WI.

Diagnostic performance of MR imaging in evaluating prognostic factors in patients with cervical cancer: a meta-analysis

OBJECTIVES

This study aims to determine the diagnostic performance of conventional magnetic resonance imaging (MRI) in assessing the distance between the tumor and the internal os, stromal infiltration, lymph node metastasis, and parametrial invasion in patients with cervical cancer.

METHODS

A systematic English-language literature search of conventional MRI in the evaluation of human cervical cancer was performed in the PubMed, Cochrane Library, Embase, and Web of Science databases from 1995 to 2018. The pooled sensitivity, specificity, diagnostic odds ratio (DOR), and positive and negative likelihood ratios (PLR and NLR) of all studies were calculated. The results were then plotted in a hierarchical summary receiver operating characteristic (HSROC) plot, and meta-regression and subgroup analyses of the parametrial invasion were also performed.

RESULTS

The pooled sensitivity, specificity, DOR, PLR, and NLR were 86%, 97%, 167.91, 24.74, and 0.15, respectively, in evaluating the internal os involvement (6 studies, 454 patients); 87%, 91%, 73.41, 10.22, and 0.14, respectively, in evaluating the stromal infiltration (11 studies, 672 patients); 51%, 89%, 8.63, 4.72, and 0.55, respectively, in evaluating the lymph node metastasis (15 studies, 997 patients); and 75%, 92%, 34.01, 9.38, and 0.28, respectively, in evaluating the parametrial invasion (19 studies, 1748 patients). The meta-regression of the parametrial invasion showed that the application of contrast enhancement was a significant factor affected the heterogeneity (p = 0.039).

CONCLUSIONS

Conventional MRI can accurately evaluate the distance between the tumor and the internal os, as well as stromal infiltration, and performs well in diagnosing the parametrial invasion. However, this method exhibited a limited ability in diagnosing the lymph node metastasis.

KEY POINTS

• MRI can help clinicians to accurately assess the distance between the tumor and the internal os, stromal infiltration, and parametrial invasion in patients with uterine cervical neoplasms. • MRI exhibits a limited ability in diagnosing the lymph node metastasis. • Management of patients with uterine cervical neoplasms becomes more appropriate.

Value of diffusion-weighted and dynamic contrast-enhanced MR in predicting parametrial invasion in cervical stromal ring focally disrupted stage IB-IIA cervical cancers

OBJECTIVES

To compare the effectiveness of diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) imaging in detecting parametrial invasion (PMI) in cervical stromal ring focally disrupted stage IB-IIA cervical cancers.

METHODS

Eighty-one patients with cervical stromal ring focally disrupted stage IB-IIA cervical cancers (PMI positive, n = 35; PMI negative, n = 46) who underwent preoperative MRI and radical hysterectomy were included in this study. Preoperative clinical variables and MRI variables were analyzed and compared.

RESULTS

The K_trans (min, mean, 10%, 25%, 50%, 75%, 90%), K_ep (min, 10%, 25%, 50%, 75%, 90%), and V_e (min, 10%, 25%, 50%, 75%, 90%) values of patients with PMI were significantly higher than patients without PMI. The apparent diffusion coefficient (ADC) value did not show statistical difference between the two groups (1.01 ± 0.21 vs. 0.97 ± 0.20 10^-3 mm²/s, p = 0.360). Tumor craniocaudal planes were higher in PMI-positive group than PMI-negative group (35.84 ± 15.39 vs. 29.70 ± 11.78 mm, p = 0.048). Tumor craniocaudal planes combined with K_epmin value showed the highest area under the curve (AUCs) of 0.775, with a sensitivity of 72.7% and a specificity of 71.1% (p = 0.000).

CONCLUSIONS

DCE parameters combined tumor craniocaudal planes may represent a prognostic indicator for PMI in cervical stromal ring focally disrupted IB-IIA cervical cancers.

Staging early cervical cancer in China: data from a multicenter collaborative

BACKGROUND

In 2018 the International Federation of Gynecology and Obstetrics (FIGO) revised the staging system of cervical cancer. This study aimed to assess the quality of staging early cervical cancer in China before the revision.

METHODS

This multicenter retrospective study included 34 tertiary hospitals in China. Medical records of patients with cervical cancer who underwent primary surgical treatment between January 2010 and December 2015 were reviewed retrospectively. All patients were clinically staged according to the 2009 FIGO staging system. Eligibility criteria included: histopathologically confirmed cervical cancer; 2009 FIGO stage IA-IIA2 based on 2009 FIGO staging system; primary surgical treatment including extrafascial, type II or type III radical hysterectomy; radical trachelectomy; with or without pelvic lymphadenectomy; regardless of surgical route via laparotomy or laparoscopy; and complete clinical and pathological data. Patients who received non-surgical treatment, neoadjuvant treatment, or those with incomplete data were excluded. The accuracy of clinical staging was assessed by comparison between clinical and pathologic stage using the latter as the reference standard.

RESULTS

A total of 23 933 cases of cervical cancer were identified and 12 681 fulfilled the inclusion criteria. Of these patients, 69.6% were staged accurately, 9.4% were clinically understaged, and 21.0% were clinically overstaged. The accuracy of stage IA, IB1, IB2, IIA1, and IIA2 was 90.0%, 87.5%, 57.4%, 20.3%, and 25.5%, respectively. The causes of stage inaccuracy were as follows: vaginal involvement (62.3%), maximal tumor diameter (24.6%), extent of cervical stromal invasion (7.1%), parametrial invasion (5.8%), bladder or rectal infiltration (0.1%), and distant metastases (0.1%).

CONCLUSION

The accuracy of staging early cervical cancer in China was suboptimal before the revision of the staging system, especially for IIA1 and IIA2. The most common reasons for staging inaccuracy were vaginal involvement and tumor diameter.

Impact of pelvic MRI in routine clinical practice on staging of IB1-IIA2 cervical cancer

Purpose: To evaluate the impact of pelvic magnetic resonance imaging (MRI) on staging of IB1-IIA2 cervical cancer in routine clinical practice. Patients and Methods: A total of 1,016 patients with IB1-IIA2 cervical cancer who underwent primary surgery and preoperative pelvic MRI between January 2009 and December 2015 were identified in a retrospective multicentre study. Data on clinical stage, MRI reports and surgicopathologic findings were extracted from medical records. The impact of MRI on clinical staging was evaluated by comparison before and after combination of MRI. Using surgicopathologic findings as the reference standard, the impact of pelvic MRI on the accuracy of clinical staging was evaluated. Furthermore, the impact on the accuracy of individual staging parameters such as maximal tumor diameter, vaginal involvement or parametrial infiltration were also evaluated. Results: After combination of pelvic MRI, clinical stage remained unchanged in 59.7%, upstaged in 17.2%, and downstaged in 23.0% of the patients. The overall accuracy of clinical staging increased from 61.0% to 81.4% in our study (P<0.05). As for individual staging parameters, the area under the curve (AUC) for maximal tumor diameter increased from 0.58 to 0.81 (P<0.05). However, the AUC for vaginal involvement decreased from 0.61 to 0.57 (P>0.05). The AUC for parametrial infiltration was also suboptimal (AUC=0.56, P<0.05). Conclusion: In routine clinical practice, MRI could increase the overall accuracy of clinical staging in IB1-IIA2 cervical cancer. For staging parameters, it only significantly increased the accuracy of maximal tumor diameter.

Contrast-enhanced ultrasonography vs MRI for evaluation of local invasion by cervical cancer

OBJECTIVE:

The purpose of this study is to compare contrast-enhanced ultrasound (CEUS) to MRI for evaluating local invasion of cervical cancer.

METHODS:

A total of 108 patients with cervical cancer were included in this study. All the enrolled patients were Stage IIA2-IVB according to the International Federation of Obstetrics and Gynecology and treated with volumetric modulated arc therapy. Tumour size in different dimensions was compared between MRI and CEUS. The correlation coefficients (r) between MRI and CEUS for diagnosing local invasion, parametrial extension, and invasion to vagina, uterine corpus and adjacent organs were assessed.

RESULTS:

Measurements by MRI and CEUS were strongly correlated in the three dimensions: left-right r = 0.84, craniocaudal r = 0.86 and anteroposterior r = 0.88. Vaginal and parametrial invasion were detected by both MRI and CEUS with moderate concordance, and invasion of uterine corpus, bladder and rectum with good concordance.

CONCLUSION:

CEUS is comparable to MRI for measuring tumour size, with good concordance for evaluating invasion of cervical cancer.

ADVANCES IN KNOWLEDGE:

CEUS is a less expensive non-invasive modality for assessment of tumour size and invasion of cervical cancer.

Identification of cervical cancer using laser-induced breakdown spectroscopy coupled with principal component analysis and support vector machine

Cervical cancer is one of the most widespread diseases in women. Traditional cancer diagnosis is extremely complicated and relies on subjective interpretation of biopsy material. In this work, laser-induced breakdown spectroscopy (LIBS) was used in cervical cancer recognition. In order to improve identification accuracy of cervical cancer by LIBS, the chemometric methods of principal component analysis (PCA) and support vector machine (SVM) were combined. The results show that the content of trace elements in normal tissues and cervical cancer tissues was significantly different. Normalized peak intensities of Na, Mg, and K in the cervical cancer tissues were significantly higher than normal tissues, and the normalized peak intensities of Ca in the normal tissues were higher than cervical cancer tissues. The identification accuracies of PCA-SVM are better than SVM, with the achieved accuracies of 94.44% and 93.06%, respectively. It can be concluded that LIBS techniques coupled with chemometric method is a potential in cancer tissue identification, which provides a preliminary research basis for real-time diagnosis of cancer tissues using LIBS.

Apparent diffusion coefficient for prediction of parametrial invasion in cervical cancer: a critical evaluation based on stratification to a Likert scale using T2-weighted imaging

PURPOSE

To evaluate the value of apparent diffusion coefficient (ADC) for determining parametrial invasion (PMI) in cervical cancer, by stratifying them into subgroups based on a Likert scale using T2-weighted imaging (T2WI).

MATERIALS AND METHODS

This retrospective study included 87 patients with FIGO stage IA2-IIB cervical cancer who underwent preoperative MRI followed by radical hysterectomy. Radiological PMI was assessed on T2WI using a six-point Likert scale and ADC values of the tumors were measured. MRI findings were compared between patients with and without PMI. Differences in ADC according to the Likert scale were also assessed.

RESULTS

19 (21.8%) patients had pathological PMI. The prevalence of PMI was significantly associated with Likert scale (P < 0.001). ADC values significantly differed according to Likert scale (P < 0.001). However, only tumors with a Likert score of 0 (MRI-invisible) had significantly greater ADC than others (P < 0.001) while no significant difference was observed among tumors with Likert scores of 1-5 (P = 0.070-0.889). Patients with PMI had significantly lower ADC values than those without PMI (P = 0.034). However, no significant difference was seen between patients with and without PMI within each Likert score group (P = 0.180-0.857).

CONCLUSION

T2WI-based Likert score for radiological PMI and ADC values of the tumor were significantly associated with pathological PMI. However, the apparent association seen between ADC values and PMI may be due to contribution of high ADC values of MRI-invisible tumors rather than reflecting their relationship.