Role of Diffusion-Weighted Images and Dynamic Contrast Enhanced
MRI diagnostic in early detection of ovarian carcinoma recurrent
Olimov B.P., postgraduate student at faculty of radiology
Supervisor: Prof. Igor Tyurin
FSBEI FPE RMACPE MOH Russia, Moscow
Ovarian carcinoma (OC) is the most common cause of death from the gynecologic malignancy. Worldwide statistic demonstrates that OC incidence is still growing up. Currently it is about 5% of all female carcinomas. OC has likelihood of recurrence despite aggressive treatment strategies, and the detection exact localization of recurrent lesions is important for guiding management and for determining the proper therapeutic approach.
The first recurrence initially identified with help either CA-125 and ultrasound (US), computed tomography (CT) imaging study, but CA-125 monitoring alone is insufficient to detect recurrent diseases. The use of convention imaging modalities such as CT or US is challenging due to the limited ability to distinguish between post-therapeutic changes and cancerous lesions. Based on the unique soft-tissue relative contrast of magnetic resonance imaging (MRI) and MRI function modalities such as diffusion-weighted imaging (DWI) and dynamic MRI with contrast enhancement (DCE), MRI has been proven useful for identifying both local and distant recurrences of OC. Thus, the aim of our study is to prospective assess of the early detected of recurrent of OC, also to assess their localizations and differential diagnostic between deposit and lymph nodes lesions with the help of DWI-MRI and DCE-MRI.
Materials and Methods:
Our study included 45 patients (age range 34-75 years) underwent examination and treatment at the N.N.Blokhin oncology center (Moscow, Russia) at 09/2016-03/2018 with dynamic control after surgical treatment by MRI (Magnetom Espree® 1.5T, Siemens-Germany): TSE T1 and T2 weighted images (T1WI&T2WI), DWI (b values=50-800) with apparent diffusion coefficient (ADC) maps and DCE MRI after gadobutrol (Gadovist®, Bayer-Germany) i.v. injection 3 ml/s at the standard dose 0.1 mmol/kg. We evaluated the presence of recurrent OC using data of T1WI&T2WI, DWI&ADC and DCE MRI in compare with surgical and histopathology findings.
Routine T1WI&T2WI in 21 (40,9%) patients had determinedly full coincidence with histology findings and this was considered as a truly positive results (TPR). In 2 (2,3%) cases false positive results (FPS) were obtained. 6 (11,4%) patients had true negative results (TNR). 16 (45,4%) patients had false negative results (FNR). Indicators of MRI diagnostic strength based on T1WI&T2WI were: accuracy - 55,3%, sensitivity - 51,4%, specificity - 85,3%. In the assessment of the diagnostic consideration of DWI&ADC and DCE MRI in 37 (81,5%) cases TPR was determined, in 6 (13,9%) patients – TNR, in 2 (4,6%) women – FNR. FPR data were not detected. Indicators of informative of MRI with DWI&ADC and DCE increased to: 96.3% of accuracy, 93.6% of sensitivity and 100% of specificity.
Conclusion: In our prospective study, the routine MRI showed higher diagnostic criteria for detection of recurrent ovarian cancer and enabled better prediction of operability with the aim for complete resection only in combination with DWI&ADC and DCE MRI. MRI in combination with DWI&ADC and DCE MRI had higher accuracy and specificity for determination tumor mass with peritoneal diseases spread and mesenteric infiltration. DWI&ADC and DCE MRI differentiate recurrent tumors from treatment-induced fibrosis or inflammation irrespective of anatomical localization. However, DWI&ADC and DCE MRI had limitation at the differential diagnostics between of the additional tumor mass along the iliac vessels and metastatic pelvis lymph nodes.
Considering the high information content of these methods, we strongly recommend to include T1WI&T2WI, DWI&ADC and DCE MRI to the MRI protocol during the surveillance of patients who underwent a special anti-tumor treatment of recurrent OC.