MR Differential Diagnosis Of Primary Fallopian Tube Carcinoma And Epithelial Ovarian Cancer

Aim: To investigate salient features of primary fallopian tube carcinoma(PFTC)upon magnetic resonance imaging(MRI)to differentiate from epithelial ovarian cancer(EOC).Methods: Twenty-one patients with PFTC and 35 patients with EOC were included.We analyzed clinical and pathologic features of patients with PFTC and EOC(including age,menstrual status,abnormal vaginal bleeding or drainage,abdominal pain,pelvic masses or triad of pathognomonic symptoms,FIGO stage,histologic types).The MRI features to be compared were as follows: laterality;maximal diameter,configuration,shape,signal intensity and enhancement pattern of solid components;hydrosalpinx,intrauterine fluid accumulation.Comparing the incidence and continuity of the narrow band with obvious enhancement surrounding lesions in different shapes of PFTC and between PFTC and EOC groups respectively;Comparing the apparent diffusion coefficient(ADC)values within the solid components of tumors between PFTC and EOC.Results: The maximal diameter of PFTC was 4.50±2.10 cm.MRI features of PFTC were unilateral(21/21,100%);mural papillary nodules(2/21,10%),sausage-like(8/21,38%),nodular(3/21,14%)or irregular(8/21,38%)shape;the solid components(22/22,100%)were isointense or hypointense on T1-weighted imaging(T1WI),hyperintense on T2-weighted imaging(T2WI)and diffusion-weighted imaging(DWI),with mild(10/21,48%),moderate(8/21,38%)or marked(3/21,14%)enhancement;associated hydrosalpinx(6/21,29%)and intrauterine fluid accumulation(3/21,10%).Significant differences between PFTC and EOC were found in the FIGO stage,maximal diameter,shape,enhancement pattern of solid components,hydrosalpinx and intrauterine fluid accumulation(p=0.002,0.005,<0.001,<0.001,0.048,respectively).The narrow band with obvious enhancement surrounding lesions were more prevalent and exhibited better continuity in PFTC than in EOC(p=0.002,0.002,respectively).There was no significant difference in the maximum ADC value,average ADC value and minimum ADC value between the two groups(p=0.640,0.465,0.195,respectively).Conclusions:(1)PFTC can be directly diagnosed by papillary nodule and sausage like shape;(2)The narrow band with obvious enhancement in PFTC is more common,and has better continuity than EOC;(3)PFTC is easy to be diagnosed by nodular lesions combined with continuous and uniform narrow band surrounding lesions;(4)When the shape is irregularand the narrow band with obvious enhancement surrounding lesions is intermittent,combining with other MRI signs: hydrosalpinx or intrauterine fluid accumulation,the diagnosis should be inclined to considered as PFTC rather than EOC;(5)The ADC values of solid components have no significance for the identification of PFTC and EOC.