IRM et TDM dans le diagnostic des tumeurs ovariennes présumées bénignes

Systematic review and meta-analysis of imaging differential diagnosis of benign and malignant ovarian tumors

BACKGROUND

With the increasing incidence of gynecological ovarian tumors, the differential diagnosis of benign and malignant ovarian tumors is of great significance for subsequent treatment. Currently, ovarian examinations commonly use computed tomography (CT) or magnetic resonance imaging (MRI). This study sought to compare the value of CT and MRI in differentiating between benign and malignant ovarian tumors.

METHODS

The PubMed, Cochrane Central Register of Controlled Trials, Embase, Web of Science, China National Knowledge Infrastructure, Wanfang, and Weipu databases were searched for published articles using the following terms "CT" or "Computed Tomography" or "MRI" or "Magnetic Resonance imaging" and "ovarian cancer" or "ovarian tumor" or "ovarian neoplasm" or "adnexal mass" or "adnexal lesion". The articles were screened and the data were extracted based on the inclusion and exclusion criteria. The Quality Assessment of Diagnostic Accuracy Studies-2 recommended by the Cochrane Collaboration was used to assess the methodological quality of the included studies, and the network meta-analysis was performed by Stata 15.0.

RESULTS

The results showed that the overall sensitivity and specificity of CT were 0.79 [95% confidence intervals (CI): 0.70-0.87] and 0.87 (95% CI: 0.80-0.92), respectively. The overall sensitivity and specificity of MRI were 0.94 (95% CI: 0.91-0.95) and 0.91 (95% CI: 0.90-0.93), respectively. The area under the curve of the CT and MRI summary receiver operating characteristics were 0.9016 and 0.9764, respectively. The positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of CT were 5.26 (95% CI: 2.78-9.93), 0.26 (95% CI: 0.13-0.50), and 22.19 (95% CI: 7.54-65.30), respectively. The positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of MRI were 8.69 (95% CI: 5.06-14.92), 0.07 (95% CI: 0.04-0.13), and 146.19 (95% CI: 68.88-310.24), respectively.

CONCLUSIONS

Compared to CT, MRI has a stronger ability to differentiate between benign and malignant ovarian tumors. It's a promising non-radiological imaging technique and a more favorable choice for patients with ovarian tumors. However, in the future, large-sample, multi-center prospective studies need to be conducted to compare the performance of MRI and CT in distinguishing between benign and malignant ovarian tumors.

[Diagnostic value of imaging (ultrasonography, doppler, CT, MR, PET-CT) for the diagnosis of a suspicious ovarian mass and staging of ovarian, tubal or primary peritoneal cancer: Article drafted from the French Guidelines in oncology entitled "Initial management of patients with epithelial ovarian cancer" developed by FRANCOGYN, CNGOF, SFOG, GINECO-ARCAGY under the aegis of CNGOF and endorsed by INCa]

Transvaginal ultrasound is the first-line examination allowing characterizing 80 to 90% of adnexal masses (LP1). If performed by an expert, a subjective analysis is optimal. If performed by a non-expert, combining the use of Simple Rules with subjective analysis can achieve the diagnostic performance of an expert (LP1). Whichever the chosen model (subjective analysis by an expert or combination of the Simple Rules with a subjective analysis by a non-expert), a second-line examination will have to be proposed in the complex or indeterminate cases (about 20% of the masses) (grade A). The best-performing second-line test for characterization is pelvic MRI (LP1). If read by an expert, a pathological hypothesis can or should be suggested (grade D). In case of non-expert reading, the use of the ADNEXMR score allows a reliable assessment of the positive predictive value of malignancy to guide the patient towards the best management (gradeC). For preoperative assessment and evaluation of resectability of ovarian, fallopian tube or primary peritoneal cancer, it is recommended to perform a chest abdomen and pelvis CT with contrast agent injection (LP2, grade B). In the event of a contraindication to the injection of iodinated contrast agent (severe renal insufficiency, GFR <30mL/min), an abdomen and pelvis MRI completed with a non-injected chest CT may be proposed (LP3, grade C). By analogy, the same examinations are recommended to evaluate the disease after neo-adjuvant chemotherapy (LP3, Recommendation grade C). Further studies will be required to determine whether PET-CT provides better lymph node assessment before retroperitoneal and pelvic lymphadenectomy. PET-CT may be used to eliminate lymph node involvement in the absence of suspicious lymph nodes on morphological examination (LP3, grade C). The report should specify the localizations leading to a risk of incomplete cytoreductive surgery and lesions outside the field explored during surgery.

Characterization of tubo-ovarian abscess mimicking adnexal masses: Comparison between contrast-enhanced CT, 18F-FDG PET/CT and MRI

0BJECTIVE: We compared the diagnostic accuracy of contrast-enhanced computed tomography (CT), fluorine 18-labeled-fludeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/CT and conventional magnetic resonance imaging (MRI) without and with diffusion-weighted imaging (DWI) for characterization of tubo-ovarian abscesses (TOAs) that mimic adnexal tumors.

MATERIALS AND METHODS

We evaluated (retrospectively) 43 patients who underwent contrast-enhanced CT, PET/CT, conventional MRI without and with DWI, and who were found to have TOAs and complex adnexal tumors. All images were evaluated independently by four radiologists using a two-point grading system. Results of contrast-enhanced CT, PET/CT, MRI without DWI, and MRI with DWI were compared for each patient using receiver operating characteristic curves. Sensitivity, specificity, and positive predictive value (PPV) were calculated and compared using the chi-square test.

RESULTS

Sensitivity of MRI with DWI (95%) was significantly higher than that of contrast-enhanced CT (78.6%), PET/CT (86.7%) and MRI without DWI (87.5%). Specificities of these modalities were not significantly different. The PPV of MRI with DWI (100%) was significantly higher than that of the other three modalities (CT, 72.4%; PET/CT 78.5%; MRI without DWI, 81.5%). Overall accuracy of MRI with DWI was significantly higher than that of the other three modalities (CT, 74.4%; PET/CT, 81.4%; MRI without DWI, 83.7%).

CONCLUSION

MRI with DWI shows high accuracy for characterization of complex ovarian lesions, and is the most useful method for differentiation of TOAs from ovarian tumors.

[Recommendations for clinical practice: Presumed benign ovarian tumors--short text]

These guidelines from the French College of Gynecologists and Obstetricians on the diagnosis and treatment of presumed benign ovarian tumors (PBOT) concern physicians whether gynecologists, obstetricians, surgeons, radiologists, pediatricians, and general practitioners. Vaginal pelvic ultrasound is the first-line imaging examination in case of PBOT in adult women (grade A). In case of pure fluid unilocular mass less than 7 cm size, ultrasound is sufficient to characterize the mass (grade A). MRI is recommended as second-line to explore indeterminate masses or masses greater than 7 cm (grade B). Serum CA125 assay is not recommended as first-line diagnostic in adult women (grade C). Among women with a pure unilocular liquid cyst, hormonal therapy is ineffective (LE1) and is not recommended (grade A). Ultrasound-guided puncture is not recommended (grade B). In adult women without history of cancer, abstention is possible in case of asymptomatic pure unilocular cyst less than 10 cm (grade B). If symptoms develop, laparoscopy is the reference approach for PBOT surgical treatment (grade A). A conservative surgical treatment (cystectomy) should be preferred to oophorectomy in non-menopausal women without previous history of cancer (grade C). In cases of suspected adnexal torsion, laparoscopic surgical exploration is recommended (grade B). Conservative treatment, untwisting without oophorectomy, is recommended for non-menopausal women whatever the estimated duration of the twist and the macroscopic appearance of the ovary (grade B). During pregnancy, expectation is recommended for asymptomatic unilocular liquid masses less than 6 cm (grade C).