MR imaging in discriminating between benign and malignant paediatric ovarian masses: a systematic review

[Ovarian masses in infants and children]

BACKGROUND

Abnormalities of the ovary are frequently seen on ultrasound examination, sometimes symptomatic, but are more commonly asymptomatic.

PURPOSE

Presentation of the most important entities of ovarian masses and their imaging features in infants and children. Discussion of criteria for differentiation between benign and potentially malignant masses.

MATERIALS AND METHODS

Review of current literature and presentation of image examples.

RESULTS

The most common lesions are ovarian cysts in infants, which usually do not require therapy. Because of the risk of torsion, surgery should be discussed for lesions with a size of 5 cm or more. Benign teratomas represent three-quarters of all solid tumors of the infantile ovary. Malignant masses are rare. The task of imaging is to assess the potential risk of malignancy, also using imaging scores.

CONCLUSIONS

Imaging plays a crucial role for therapeutic considerations. Depending on the potential risk, ovarian-sparing surgery is preferred to preserve fertility, as long as the oncologic risk is reasonable.

Differentiating nasopharyngeal carcinoma from lymphoma in the head and neck region using the apparent diffusion coefficient (ADC) value: a systematic review and meta-analysis

Purpose

This study aimed to assess the applicability of the apparent diffusion coefficient (ADC) for differentiating nasopharyngeal carcinoma (NPC) from lymphomas in the head and neck region.

Material and methods

Four databases, including PubMed, the Cochrane Library, EMBASE, and Web of Science, were searched systematically to find relevant literature. The search date was updated to 8 September 2022, with no starting time restriction. The methodological quality of the studies was evaluated using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Firstly, a random-effects model was used in a meta-analysis of continuous variables with low heterogeneity to determine the overall effect size, which was reported as the standard mean difference (SMD). Then, bivariate random effects modelling was used to calculate the combined sensitivity and specificity. The area under the curve (AUC) for each diffusion parameter was calculated after constructing summary receiver operating characteristic curves. The presence of heterogeneity was evaluated using subgroup and meta-regression analysis.

Results

Twelve studies involving 181 lymphoma and 449 NPC lesions (N = 630) in the head and neck region were included, of which 5 studies provided sufficient data for pooling diagnostic test accuracy. A meta-analysis of the 12 studies using a random-effects model yielded an SMD of 1.03 (CI = 0.76-1.30; p = 0.00001), implying that NPC lesions had a significantly higher ADC value than lymphoma lesions. By pooling 5 standard DWI studies, the pooled sensitivity and specificity of ADC were 0.90 (95% CI: 0.82-0.95) and 0.63 (95% CI: 0.52-0.72), respectively. The area under the curve (AUC) calculated from the SROC curve was 0.74 (95% CI: 0.70-0.78).

Conclusions

According to this systematic review and meta-analysis, nasopharyngeal carcinoma has a significantly higher ADC value than lymphomas. Furthermore, while ADC has excellent sensitivity for distinguishing these 2 types of tumours, its specificity is relatively low, yielding a moderate diagnostic performance. Further investigations with larger sample sizes are required.

Ovarian-sparing surgery for ovarian tumors in children: A systematic review and meta-analysis

INTRODUCTION

An increased number of children and adolescents with ovarian tumors have been managed with ovarian-sparing surgery in the last few years. However, comprehensive data on fertility outcomes and local relapse are scarce. In this study, we systematically describe the contemporary outcomes of ovarian-sparing surgery, as reported in the literature.

MATERIALS AND METHODS

Using PRISMA guidelines, we analyzed studies reporting ovarian-sparing techniques for ovarian tumors in children and adolescents. from 1980 to 2022. Reports with fewer than three patients, narrative reviews, and opinion articles were excluded. Statistical analysis was performed for dichotomous and continuous variables.

RESULTS

Of 283 articles screened, 16 papers (3057 patients) met inclusion criteria (15 retrospective/1 prospective) and were analyzed. The vast majority of studies had no long-term fertility follow-up data and direct comparison between ovarian-sparing surgery vs oophorectomy was reported in only a few studies. Ovarian sparing surgery was not associated with worse oncologic outcomes in terms of (i) tumour spillage or (ii) recurrence rates, and of key importance allowed a higher ovarian reserve at long term follow-up.

CONCLUSIONS

Ovarian-sparing surgery is a safe and feasible technique for benign tumors. Long-term outcome studies are needed to show efficacy and fertility preservation.

Imaging of pediatric ovarian tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper

Ovarian tumors in children are uncommon. Like those arising in the adult population, they may be broadly divided into germ cell, sex cord, and surface epithelium subtypes; however, germ cell tumors comprise the majority of lesions in children, whereas tumors of surface epithelial origin predominate in adults. Diagnostic workup, including the use of imaging, requires an approach that often differs from that required in an adult. This paper offers consensus recommendations for imaging of pediatric patients with a known or suspected primary ovarian malignancy at diagnosis and during follow-up.

Therapeutic Management and Prognostic Factors for Ovarian Malignant Tumours in Adolescents: A Comprehensive Review of Current Guidelines

Background: Ovarian malignant tumours are rarely diagnosed in adolescents but may have a significant impact on their survival, future fertility and quality of life. The management of such cases is rather complex and requires expertise and careful planning according to scarce existing evidence and recommendations. Objective: The aim of this study was to review and compare recommendations from published guidelines regarding the diagnosis, prognosis and treatment of malignant ovarian tumours in adolescents. Evidence acquisition: A comparative descriptive/narrative review of guidelines issued by L’Observatoire des Tumeurs Malignes Rares Gynécologiques, the British Society for Paediatric & Adolescent Gynaecology, the European Society for Medical Oncology, the European Society of Gynecological Oncology-European Society for Paediatric Oncology and the European Cooperative Study Group for Pediatric Rare Tumors was conducted. Results: All guidelines recommend a thorough diagnostic work-up, consisting of both imaging tests and serum tumour marker measurement, as well as the use of immunohistochemical methods to confirm the diagnosis and complete surgical staging prior to constructing the treatment plan. There is a lack of recommendations regarding the assessment of prognostic factors, with only one guideline providing detailed information. Treatment strategies, as suggested by the majority of guidelines and with only a few discrepancies between them, should include both surgery and adjuvant therapies, mainly chemotherapy, with great emphasis on fertility preservation when it is considered oncologically safe and on the significance of regular and long-term follow-up. Conclusions: There is a significant degree of agreement among recommendations of existing guidelines. The reported differences, although limited, highlight the need for the adoption of an international consensus in order to further improve the management of adolescent ovarian cancer.

Artificial intelligence performance in image-based ovarian cancer identification: A systematic review and meta-analysis

BACKGROUND

Accurate identification of ovarian cancer (OC) is of paramount importance in clinical treatment success. Artificial intelligence (AI) is a potentially reliable assistant for the medical imaging recognition. We systematically review articles on the diagnostic performance of AI in OC from medical imaging for the first time.

METHODS

The Medline, Embase, IEEE, PubMed, Web of Science, and the Cochrane library databases were searched for related studies published until August 1, 2022. Inclusion criteria were studies that developed or used AI algorithms in the diagnosis of OC from medical images. The binary diagnostic accuracy data were extracted to derive the outcomes of interest: sensitivity (SE), specificity (SP), and Area Under the Curve (AUC). The study was registered with the PROSPERO, CRD42022324611.

FINDINGS

Thirty-four eligible studies were identified, of which twenty-eight studies were included in the meta-analysis with a pooled SE of 88% (95%CI: 85-90%), SP of 85% (82-88%), and AUC of 0.93 (0.91-0.95). Analysis for different algorithms revealed a pooled SE of 89% (85-92%) and SP of 88% (82-92%) for machine learning; and a pooled SE of 88% (84-91%) and SP of 84% (80-87%) for deep learning. Acceptable diagnostic performance was demonstrated in subgroup analyses stratified by imaging modalities (Ultrasound, Magnetic Resonance Imaging, or Computed Tomography), sample size (≤300 or >300), AI algorithms versus clinicians, year of publication (before or after 2020), geographical distribution (Asia or non Asia), and the different risk of bias levels (≥3 domain low risk or < 3 domain low risk).

INTERPRETATION

AI algorithms exhibited favorable performance for the diagnosis of OC through medical imaging. More rigorous reporting standards that address specific challenges of AI research could improve future studies.

FUNDING

This work was supported by the Natural Science Foundation of China (No. 82073647 to Q-JW and No. 82103914 to T-TG), LiaoNing Revitalization Talents Program (No. XLYC1907102 to Q-JW), and 345 Talent Project of Shengjing Hospital of China Medical University (No. M0268 to Q-JW and No. M0952 to T-TG).

Diffusion-Weighted Magnetic Resonance Imaging: Clinical Potential and Applications

Since its discovery in the 1980s [...].

Standardizing the surgical management of benign ovarian tumors in children and adolescents: A best practice Delphi consensus statement

AIM

No widely agreed consensus protocols exist for the management of benign ovarian tumors (BOT) in children. This presents a substantial risk for suboptimal management. We aimed to generate multispecialty consensus guidance to standardize surgical management and provide a clear follow-up protocol for children with BOTs.

METHODS

Prospective two-round confidential e-Delphi consensus survey distributed among multispecialty expert panel; concluded by two semistructured videoconferences.

MAIN RESULTS

Consensus was generated on these core outcome sets: preoperative/intraoperative management; follow-up; adolescent gynecology referral. (1) Children with BOTs should receive the same management as other patients with potentially neoplastic lesions: Preoperative discussion at a pediatric oncology multidisciplinary meeting to risk stratify tumors, and management by health professionals with expertise in ovarian-sparing surgery and laparoscopy. (2) Ovarian-sparing surgery for BOTs should be performed wherever possible to maximize fertility preservation. (3) Ovarian masses detected during emergency laparoscopy/laparotomy should be left in situ wherever feasible and investigated appropriately (imaging/tumor markers) before resection. (4) Follow-up should be undertaken for all patients after BOT resection. Patients should be offered referral to adolescent gynecology to discuss fertility implications.

CONCLUSION

This best practice Delphi consensus statement emphasizes the importance of managing children with BOTs through a well-defined oncological MDT strategy, in order to optimize risk stratification and allow fertility preservation by ovarian-sparing surgery wherever possible.

What Should Be the Topics of a Prospective Study on Ovarian Masses in Children?—Results of a Multicenter Retrospective Study and a Scoping Literature Review

Purpose: to determine management problems of ovarian masses in girls in order to form a baseline for prospective randomized studies of the established topics and quality improvement of our management. Materials and Methods: We performed a national analysis of clinical aspects of ovarian masses in girls operated on in Poland, analyzed retrospectively medical files of all consecutive patients aged 0–18 who underwent surgeries for ovarian lesions between 2012 and 2017 at 17 pediatric surgical departments and complemented the analysis with a scoping review of a recent primary research related to ovarian masses in children. Results: The study group comprised 595 patients. Forty-four (7.39%) girls were diagnosed with malignant tumors. The overall preservation rate was 64.54%. The analysis revealed that positive tumor markers (OR = 10.3), lesions larger than 6 cm (OR = 4.17) and solid mass on ultrasound examination (OR = 5.34) are interdependent variables differentiating malignant tumors from non-malignant lesions (X42 = 79.1; p = 0.00000). Our scoping review revealed 10 major branches of research within the topic of ovarian masses in pediatric population. Conclusions: We have developed an overview of the field with the emphasis on the local environment. Our next step is a multi-institutional prospective study of a quality improvement project implementation based on the obtained knowledge.

Assessment of placental abruption with diffusion-weighted imaging

AIM

To investigate whether placental abruption without fetal distress could be assessed by apparent diffusion coefficient (ADC) values in magnetic resonance imaging (MRI).

METHODS

We conducted a retrospective case-control study at a single center. ADC values at the lesions of placental abruption in the abruption group (n = 8) were compared to those in the control group (n = 32). In the abruption group, ADC values at the sites of abruption were also compared to those at the nonabruption sites within the same placenta.

RESULTS

The ADC values in the placental area above the abruption site in the abruption group showed lower values than those in the control group when the slice containing the umbilical cord insertion site was set as the reference, and those values were compared in each corresponding slice. Compared with average ADC values, those above the abruption site in the abruption group were also significantly lower than those in the control group (p < 0.001). Furthermore, ADC values at the area above abruption were lower than those at the nonabruption area of all planes in the abruption group.

CONCLUSIONS

ADC values at the lesions above the placental abruption site were reduced compared to those in the normal placenta and those in the nonabruption area. Thus, it would be helpful to understand the pathophysiology of placental abruption in expectant management, although further investigations would be needed.

Construction and Verification of a Predictive Model for Risk Factors in Children With Severe Adenoviral Pneumonia

OBJECTIVE

To construct and validate a predictive model for risk factors in children with severe adenoviral pneumonia based on chest low-dose CT imaging and clinical features.

METHODS

A total of 177 patients with adenoviral pneumonia who underwent low-dose CT examination were collected between January 2019 and August 2019. The assessment criteria for severe pneumonia were divided into mild group (N = 125) and severe group (N = 52). All cases divided into training cohort (N = 125) and validation cohort (N = 52). We constructed a prediction model by drawing a nomogram and verified the predictive efficacy of the model through the ROC curve, calibration curve and decision curve analysis.

RESULTS

The difference was statistically significant (P < 0.05) between the mild adenovirus pneumonia group and the severe adenovirus pneumonia group in gender, age, weight, body temperature, L/N ratio, LDH, ALT, AST, CK-MB, ADV DNA, bronchial inflation sign, emphysema, ground glass sign, bronchial wall thickening, bronchiectasis, pleural effusion, consolidation score, and lobular inflammation score. Multivariate logistic regression analysis showed that gender, LDH value, emphysema, consolidation score, and lobular inflammation score were severe independent risk factors for adenovirus pneumonia in children. Logistic regression was employed to construct clinical model, imaging semantic feature model, and combined model. The AUC values of the training sets of the three models were 0.85 (0.77-0.94), 0.83 (0.75-0.91), and 0.91 (0.85-0.97). The AUC of the validation set was 0.77 (0.64-0.91), 0.83 (0.71-0.94), and 0.85 (0.73-0.96), respectively. The calibration curve fit good of the three models. The clinical decision curve analysis demonstrates the clinical application value of the nomogram prediction model.

CONCLUSION

The prediction model based on chest low-dose CT image characteristics and clinical characteristics has relatively clear predictive value in distinguishing mild adenovirus pneumonia from severe adenovirus pneumonia in children and might provide a new method for early clinical prediction of the outcome of adenovirus pneumonia in children.

Ovarian lesions and tumors in infants and older children

Objectives

Ovarian lesions are rare but frequent in children. Patients could present with abdominal pain, but ovarian lesions could also be incidentally found on ultrasound. Awareness is required in cases with acute, severe lower abdominal pain, as ovarian torsion could be the cause. Other lesions can be cysts or benign or malignant ovarian tumors. Thus, the aim of this paper is to review typical ovarian lesions according to age, imaging and laboratory findings, and surgical management.

Methods

We retrospectively analysed the patient charts of 39 patients aged 10.4 ± 6.1 years (from 3 months to 18 years) with ovarian lesions treated in our institution between 01/2009 and 08/2020. All clinical and pathological findings of infants and children operated on for ovarian lesions were included.

Results

Ovarian lesions in children younger than 2 years of age were typically ovarian cysts, and ovarian tumors were not observed in this age group. In older children over 10 years of age, tumors were more common – with mostly teratoma or other germ cell tumors, followed by epithelial tumors. Moreover, acute or chronic ovarian torsion was observed in all age groups. In general, ovarian tumors were much larger in size than ovarian cysts or twisted ovaries and eventually showed tumor marker expression of AFP or ß-HCG. Simple ovarian cysts or twisted ovaries were smaller in size. Surgery for all ovarian lesions should aim to preserve healthy ovarian tissue by performing partial ovariectomy.

Conclusions

In adolescent girls with acute abdominal pain, immediate laparoscopy should be performed to rule out ovarian torsion. Careful imaging evaluation and the assessment of tumor markers should be performed in painless ovarian lesions to indicate an adequate surgical ovarian-sparing approach.

Soft tissue sarcomas: IVIM and DKI correlate with the expression of HIF-1α on direct comparison of MRI and pathological slices

OBJECTIVE

To investigate the correlation of intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) parameters with the expression of HIF-1α in soft tissue sarcoma (STS).

METHODS

This prospective study was approved by the institutional ethics committee. Written informed consent was obtained from all patients. Forty patients with STS who underwent 3.0 T MRI, including IVIM and DKI, were included in the study. Standard apparent diffusion coefficient (ADC), true ADC (D_slow), pseudo ADC (D_fast), perfusion fraction (f), mean kurtosis (MK), and mean diffusivity (MD) of each lesion were independently analyzed by two observers. An MRI-pathology control method was used to ensure correspondence between the MRI slices and the pathological sections. Spearman analysis, independent sample t test, Mann-Whitney U test, chi-squared test, and receiver operating characteristic (ROC) curve analysis were performed.

RESULTS

D_slow and MD values showed a negative correlation with HIF-1α expression (r = - 0.469, - 0.588). MK and f values showed a positive correlation with HIF-1α expression (r = 0.779, 0.572). D_slow, MD, MK, and f values showed significant differences between the high- and low-expression groups. The MK value showed the best diagnostic ability. The optimal cut-off MK value of 0.604 was associated with 78.3% sensitivity and 88.2% specificity (area under the curve, 0.867).

CONCLUSIONS

This preliminary study demonstrated the association of IVIM and DKI parameters with the expression of HIF-1α in STS.

KEY POINTS

• IVIM and DKI parameters are correlated with the expression of HIF-1α in STS. • The MRI-pathology control method can be used in clinical studies to ensure correspondence between MRI slices and pathology sections.

The diagnostic value of magnetic resonance imaging in differentiating benign and malignant pediatric ovarian tumors

BACKGROUND

The diagnostic workup of ovarian tumors in children and adolescents is challenging because preserving fertility, in addition to oncological safety, is of particular importance in this population. Therefore, a thorough preoperative assessment of ovarian tumors is required.

OBJECTIVE

To investigate the diagnostic value of MR imaging in differentiating benign from malignant ovarian tumors in children and adolescents.

MATERIALS AND METHODS

We conducted a retrospective study of all children and adolescents age <18 years who underwent MR imaging of ovarian tumors during 2014-2019 at a pediatric specialty center. Two radiologists reviewed all MR imaging. We used pathology reports to define the histological diagnosis.

RESULTS

We included 30 girls who underwent MR imaging for an ovarian tumor. Signs indicative for malignancy were tumors with a diameter ≥8 cm, with areas of contrast enhancement, irregular margins, extracapsular tumor growth, and ascites. All benign and malignant ovarian tumors were correctly identified by the radiologists.

CONCLUSION

The diagnostic utility of MR imaging in classifying ovarian tumors in children and adolescents as benign or malignant is promising and might aid in defining the indication for ovarian-sparing versus non-ovarian-sparing surgery. We recommend evaluating these tumors with MR imaging prior to deciding on surgical treatment.

A Nomogram Combined Radiomic and Semantic Features as Imaging Biomarker for Classification of Ovarian Cystadenomas

Objective: To construct and validate a combined Nomogram model based on radiomic and semantic features to preoperatively classify serous and mucinous pathological types in patients with ovarian cystadenoma.

Methods: A total of 103 patients with pathology-confirmed ovarian cystadenoma who underwent CT examination were collected from two institutions. All cases divided into training cohort (N = 73) and external validation cohort (N = 30). The CT semantic features were identified by two abdominal radiologists. The preprocessed initial CT images were used for CT radiomic features extraction. The LASSO regression were applied to identify optimal radiomic features and construct the Radscore. A Nomogram model was constructed combining the Radscore and the optimal semantic feature. The model performance was evaluated by ROC analysis, calibration curve and decision curve analysis (DCA).

Result: Five optimal features were ultimately selected and contributed to the Radscore construction. Unilocular/multilocular identification was significant difference from semantic features. The Nomogram model showed a better performance in both training cohort (AUC = 0.94, 95%CI 0.86–0.98) and external validation cohort (AUC = 0.92, 95%CI 0.76–0.98). The calibration curve and DCA analysis indicated a better accuracy of the Nomogram model for classification than either Radscore or the loculus alone.

Conclusion: The Nomogram model combined radiomic and semantic features could be used as imaging biomarker for classification of serous and mucinous types of ovarian cystadenomas.