ROLE OF MAGNETIC RESONANCE IMAGING IN DIFFERENTIATING BENIGN FROM MALIGNANT OVARIAN TERATOMAS

Abstract

Background: Teratoma is the most common type of ovarian germ cell tumor, accounting for about 20% of ovarian tumors. There are major differences in treatment strategies and prognosis between benign and malignant teratomas. Ultrasound is considered the first primary diagnostic tool for ovarian tumors, however, there are still many limitations. Magnetic resonance imaging (MRI) has high accuracy in diagnosing ovarian teratomas, along with enhancement kinetic techniques and apparent diffusion coefficients to help analyze many characteristics of this type of tumor.

Objective: Determine the role of routine MRI with contrast agent injection, enhancement kinetics, and apparent diffusion coefficient in the differential diagnosis of benign and malignant ovarian teratomas.

Methods: CrossA cross-sectional descriptive study was conducted on 181 patients undergoing routine magnetic resonance imaging with contrast agent injection, enhancement kinetic technique and preoperative pelvic diffusion-weighted magnetic resonance imaging. From the pathology results, the groups of benign and malignant teratomas were determined from the pathology results the groups of benign and malignant teratomas, to describe the observed magnetic resonance imaging features and determine the value of each feature in the differential diagnosis of benign and malignant groups. count.

Results: 181 patients had a total of 203 ovarian teratomas, including 173 benign ovarian teratomas and 30 malignant ovarian teratomas. The median age of the malignant tumor group was lower than that of the benign tumor group (24 and 31 years old), with mature teratomas accounting for the highest proportion in the entire study sample (84.2%). Valuable features included presence of solid tissue (Se: 100%; Sp: 93.1%), tumor size ≥13.4 cm (Se: 73.3%; Sp: 83.2%), tumor size Fatty deposits are only fat distribution in small foci (Se: 80%; Sp: 99.4%), irregular tumor walls are irregular (Se: 90%; Sp: 94.2%); There is abdominal fluid (Se: 60%; Sp: 90.7%), solid tissue size ≥7 cm (Se: 73.3%; Sp: 100%), solid tissue size and tumor size ratio ≥0 ,4 (Se: 88.7%; Sp: 91.7%), high solid tissue signal on T2WI (Se: 63.3%; Sp: 100%), ADC value ≤0.68 x 10-3 mm2/s (Se: 36.1%; Sp: 100%), d. Pharmacorug capture kinetics do did not play a roleappear to be associated. Combining the characteristicsIn combining examination, the combination with of solid tissue and irregular tumor walls has yielded Se: 95.1%, Sp: 90%); The the combination of solid tissue size ≥ 7 cm and the ratio of solid tissue size and tumor size ≥0.4 has yielded Se: 80.9%, Sp: 73.3%.

Conclusion: Many imaging features on routine MRI are valuable in the differential diagnosis of benign and malignant ovarian teratomas, of which solid tissue is the most important feature, espectially the ratio between the size of the solid component and the size of the tumor. The apparent diffusion coefficient of solid tissue is 0.68 x 10-3 mm2/s has yielded a specificity of 100%, sensitivity of 36.1% and accuracy of 54.8% in diagnosing malignant ovarian tumors. Enhancement kinetics do did not help differentiate between benign and malignant ovarian teratomas.

Keywords: teratoma; ovarian tumors; characteristics; magnetic resonance imaging