Diagnosis And Staging Of The Diffusion-weighted Imaging Combined With Dynamic Contrast Enhancement In Uterus Cervical Carcinoma

Objective: To optimize the MRI examining series of cervical carcinoma and evaluate the value of MRI in preoperative staging of uterine cervical carcinoma especially the diffusion-weighted imaging (DWI) and dynamic contrast enhancement (DCE) features in the diagnosis and staging of cervical carcinoma. To improve the accuracy of MRI in the staging of cervical carcinoma by investigating the associated MRI quantitative data: apparent diffusion coefficient (ADC),arterial phase relative signal increase (ARSI%) and maximal relative signal increase (MRSI%).Material and Methods: Forty cases by scratch-pathologically confirmed cervical carcinoma patients with MRI data were analyzed, of which 20 cases underwent surgery within one week. The mean age was 43.7±2.8 years old. Conventional MRI and DCE scanning were performed in all the patients with GE Signa MR /i 1.5-T or GE Signa 1.5T HD echospeed MR scanner, DWI were performed at the same time in 27 cases of them. MR imaging features and the scores of different direction and sequences were recorded, and the contrast to noise ratio(CNR) was calculated. ADC and time-intensity curve (TIC) were obtained with GE Functool 4.3 workstations. ARSI% and MRSI% were also obtained with it. The pathological type, degree of differentiation and depth of invasion were recorded in surgical patients, the rest cases that can not be treated by surgery were judged with the clinical comprehensive judgement. The statistical package for social sciences (version 11.5) was used for all statistical analyses, and independent t-test and Randomized block ANOVA were used to analyze the data, P <0.05 was considered a significant difference.Results:1. Thirty-nine cases (except one case of carcinoma in situ was negative) were found as solid mass. It was high signal in T2WI and iso-signal in T1WI in 34 cases. All of the 27 cases performed DWI were obviously high signal intensity in DWI. All the masses of 39 cases were enhanced at 16s in DCE, and contrast agent was found withdraw from the centre in 31 cases in delayed scanning. There was maximum signal contrast between lesions and the surrounding normal tissue in the in the early arterial phase, the contrast decreased with time. The abnormal signal in the peri-uterus region in 14 cases was low signal in T1WI, high signal in both T2WI and DWI. There were 11 cases enhanced with the same pattern as the cancer foci.2. Axial and saggital T2WI, axial DWI and sagittal DCE were better than other sequences when showing the focus of cancer, while axial T1WI, axial DWI and coronal enhanced scanning were better at showing the peri-uterus tissue comparing to others. The CNR of lesions in DWI was significantly higher than T1WI and T2WI.3. The accuracy rate of MRI was 85% comparing with staging confirmed by surgery. The accuracy rate of the judgement of the integrity of junctional zone was 100%. Coincidence rate of 20 cases without surgery was 55%, compared with Comprehensive clinical stages. 4. ADC value of tumor was 1.21±0.47, which was lower than 2.34±0.23 of normal tissue (P <0.05), there was significant difference of ADC value when grouping with size (3 cm for the dividing line), shape (regular or irregular), border (clear or not). ARSI% of tumor was 1.28±0.37, which was higher than normal tissue (0.68±0.44) (P<0.05), but there was no significant difference of MRSI%. ARSI% and MRSI% of diameter > 3 cm group were higher than≤3 cm group, which was higher in the peri-uterus tissue infiltration group than that of confined group (P<0.05)Conclusion:1. MRI multi-directional, multi-sequence imaging can show the cervical carcinoma lesions and peri-uterus organizations clearly. The optimized sequences of MRI examination of cervical cancer should be axial T1WI, axial and sagittal T2WI, axial DWI, sagittal DCE and coronal delay scanning.2. The accuracy of MRI staging confirmed by surgery was 85%. The accuracy of the judgement to the integrity of junctional zone was 100%. MRI may play an important role in determining treatment strategy and assessing prognosis.3. DWI is easier than conventional MRI in showing the lesions for a high CNR of DWI. So DWI could have some value in evaluation of the stage beforeⅠb. There was correlation between ADC and some of morphologic information of uterus cervical cancers, which suggesting that DWI can reflect more details, which also provide DWI a possibility of specific diagnosis.4. There is a a good signal contrast between cervical carcinoma and normal tissue in early arterial phase in DCE which is conducive to further improve the detection rate of small lesions. To grouping with tumor size and whether peri-uterus tissue infiltration, the differences of ARSI% and MRSI% were statistically significant, which may be helpful in some degree in prognostic assessment and staging of the uterus cervical cancer.