The new 2018 FIGO system promotes the value of imaging modalities especially MRI imaging to increase the accuracy of tumor staging and guide treatment/monitoring. DWI increases the staging accuracy of MRI by permitting better evaluation of tumor size, extra uterine extension, and nodal infiltration, factors that affect treatment selection and planning [11,12,13].
In this study, the age of the included patients with suspected cervical cancers ranged from 39 to 63 years, M = ± 44.6 years. The abnormal vaginal bleeding was the main complaint in 42 patients while 18 patients complained of malodorous discharge and vaginal discomfort. This was in agreement with Sherif HA et al., who studied 20 female patients age 30–75 years with a clinical picture of abnormal vaginal bleeding and vaginal discharge [14], and also with Rezvani M et al. who stated that cancer cervix typically presents in younger women with an average age around 45 years, presented by abnormal vaginal bleeding, discomfort, and malodorous discharge as the first complaints [6].
We classified the studies 60 cases according to the histopathological results into 2 groups: 46 malignant lesions (group 1), 34 squamous cell carcinoma lesions, 8 adenocarcinomas, and 4 undifferentiated carcinoma and 14 benign lesions (group 2), 8 cervical polyps, 4 chronic cervicitis with nabothian cysts, and 2 fibroid lesions.
Our findings were in coincidence with that of Mahmoud SM et al., who found that the pathology of the included cases was sq. cell carcinoma in 72%, adenocarcinoma in 12%, sarcomatoid cervical carcinoma in 4%, spindle cell tumor in 4%, basaloid carcinoma in 4%, and undifferentiated carcinoma in 4 %[15], and with Dashottar S et al., who reported that out of the studied 35 cases, 33 (94.3%) were sq. cell carcinoma, 1 (2.9%) was papillary adenocarcinoma, and 1 (2.9%) was small cell carcinoma [16]. However, Sherif HA et al. found that the histopathological diagnosis revealed adenocarcinoma in 4 cases (20%), squamous cell carcinoma in 15 cases (75%), and chronic cervicitis in 1 case (5%) [14].
MR imaging represents the most valuable imaging modality for the detection of the primary tumor, nodal involvement, and local spread. It is also the best modality for showing recurrent disease and monitoring therapeutic response [17].
In the present work, the imaging findings revealed poor MRI signal characterization of pathologically proved different lesions as 27/30 cervical lesions showed iso- to hypointense signals on T1WI and moderate hyper-intense signals on T2WI with variable contrast enhancement regardless of benign or malignant etiology; however, 6 lesions (4 chronic cervicitis with nabothian cyst and 2 degenerated leiomyoma) showed iso- to low signal on T1WI and mixed/intermediate-high signals in T2WI.
Our findings were in concordance with Yoshikazu O who stated that some tumors or tumor-like lesions can show similar MR imaging findings, such as adenocarcinoma, adenoma malignum, and florid endocervical hyperplasia [18]. However, Mahmoud SA found that hypointense T1 signal was seen in 34/70 (48.5%) cases, isointense signal in 28/70 (40%) cases, hyperintense T1 signal in 6/70 (8.5%) cases, and heterogeneous signal intensity in 2/70 (2.8%). T2WIs showed a hyperintense signal in 62/70 (88%) cases and intermediate signal in 2/70 (2.8%) cases and heterogeneous signal intensity in 6/70 (8.5%) [19]. Tamai KT et al. found that degenerated leiomyomas (7 lesions) showed low SI on T1-weighted images with areas of high SI on T2-weighted images [20]. Patel et al. reported that cervical tumors tend to give iso- to high signal compared to cervical stroma on T2WI [21].
The diffusion-weighted image (DWI) visualizes the local microstructural characteristics of water diffusion. High intensity on DWI with low apparent diffusion coefficients (ADC) is suggestive for malignant polyp with hypercellular nature, whereas benign polyps tend to show higher ADC value [22]. Our results revealed that all studied malignant cervical focal lesions (n = 46) showed positive diffusion restriction at high b value (b = 800) with relatively low ADC values that ranged from 0.86 to 1.15 × 10−3 mm2/s, M = 0.92 ± 0.71 × 10−3 mm2/s, while 8/14 benign cervical lesions were diffusion negative in high b value (b = 800) and 3 lesions (4 ch. cervicitis with nabothian cyst and 2 degenerated fibroid) showed mixed diffusion changes. The ADC value of 10/14 benign focal lesions were relatively high that ranged from 1.57 to 2.4 × 10−3 mm2/s (M = 1.7 ± 0.31 × 10−3 mm2/s); however, atypical lesions (chronic cervicitis with nabothian cyst and degenerated fibroid) showed low ADC values that ranged from 0.86 to 1.2 × 10−3 mm2/s (M = 0.1 ± 0.19). This is may be attributed to the presence of necrosis and focal signal intensity changes as well as susceptibility artifacts. These result findings matched with many other studies which concluded the reported mean ADC values for both squamous cell carcinoma and adenocarcinoma cases to be less than 1 × 10−3 mm2/s, averaging 0.88–0.91 × 10−3 mm2/s, 0.8827 × 10−3 mm2/s, and 0.72 ± 0.168 × 10−3 mm2/s, respectively [23,24,25]. Also, Mahmoud SA concluded that in the present study, the mean ADC value for malignant lesions was 0.82 × 10−3 ± 0.1 SD mm2/s [18], and Sherif HA et al. stated that the mean ADC value of cervical carcinoma in our study was 0.82 × 10−3 mm2/s [14].
According to these study results, multiparametric MRI could detect all cervical focal lesions but with poor pathological characterization, achieving 72.37% sensitivity, 37.50% specificity, 63.33% accuracy, 76.19% PPV, and 33.33% NPV. When adding DWI with ADC value measurements at high b value (b = 800) to MRI exam, it showed a higher diagnostic accuracy with good lesion pathological characterization that achieved 95.65% sensitivity, 71.43% specificity, 90% accuracy, 91.67 PPV, and 83.33% NPV. Our results matched with Mahmoud SA et al. results which revealed that DWI-MRI showed sensitivity 100%, specificity 50%, accuracy 97%, PPV 97%, and NPV 100%, and the low percentage of the specificity in this study was due to the low number of true negative patients [19], and Chen et al. found that the sensitivity and specificity of DW-MRI for tumor detection were 100% and 84.8%, respectively. DWI showed 100% sensitivity, a positive predictive value [26]. Mahmoud SM reported that DW-MRI revealed sensitivity, specificity, PPV, and accuracy of 100%, 50%, 97%, and 97% respectively [18]. Also, Exner M. et al. concluded that the use of DWI led to an increase in sensitivity of infiltrated adjacent tissue (from 86 to 90%) and detection of lymph node metastases (from 47 to 67%) [27].