Diagnostic Performance of MRI for Assessing Parametrial Invasion in Cervical Cancer: A Head-to-Head Comparison between Oblique and True Axial T2-Weighted Images

OBJECTIVE: To directly compare the diagnostic performance of true and oblique axial T2-weighted imaging (T2WI) for assessing parametrial invasion (PMI) in cervical cancer. MATERIALS AND METHODS: This retrospective study included 71 women with treatment-naive cervical cancer who underwent MRI that included both oblique and true axial T2WI, followed by radical hysterectomy. Two blinded radiologists (Radiologist 1 and Radiologist 2) independently assessed the presence of PMI on both sequences using a 5-point Likert scale. Receiver operating characteristic (ROC) curve analysis was performed, with a subgroup analysis for tumors sized > 2.5 cm and ≤ 2.5 cm in diameter. Inter-reader agreement was assessed with kappa (k) statistics. RESULTS: At hysterectomy, 15 patients (21.1%) had PMI. For Radiologist 1, the area under the ROC curve (AUC) was greater for oblique axial than for true axial T2WI {0.941 (95% confidence interval [CI] = 0.858–0.983) vs. 0.917 (95% CI = 0.827–0.969), p = 0.027}. The difference was not significant for Radiologist 2 (0.879 [95% CI = 0.779–0.944] vs. 0.827 [95% CI = 0.719–0.906], p = 0.153). For tumors > 2.5 cm, AUC was greater with oblique than with true axial T2WI (0.906 vs. 0.860, p = 0.046 for Radiologist 1 and 0.839 vs. 0.765, p = 0.086 for Radiologist 2). Agreement between the radiologists was almost perfect for oblique axial T2WI (k = 0.810) and was substantial for true axial T2WI (k = 0.704). CONCLUSION: Oblique axial T2WI potentially provides greater diagnostic performance than true axial T2WI for determining PMI, particularly for tumors > 2.5 cm. The inter-reader agreement was greater with oblique axial T2WI.

Value of high-definition magnetic resonance imaging in preoperative evaluation of stage b -Ⅱb cervical cancer / 第二军医大学学报

Objective To explore the application value of high-definition magnetic resonance imaging (MRI) in the assessment of preoperative stage B-ⅡB cervical cancer. Methods A retrospective analysis was conducted on 94 patients with cervical cancer who had received preoperative pelvic examination in Changhai Hospital of Navy Medical University (Second Military Medical University) from Mar. 2015 to Jun. 2017. Fifty-eight of them received conventional MRI examination and 36 received high-definition MRI examination. The accuracy, sensitivity and specificity of the three methods for vaginal and parametrial invasion were evaluated using the postoperative pathological assessments as the gold standard. And the Kappa test was used to perform consistency analysis. Results For vaginal invasion, the accuracy, sensitivity and specificity of pelvic examination were 63.8% (60/94), 53.7% (29/54) and 77.5% (31/40), respectively; those of conventional MRI examination were 58.6% (34/58), 48.5% (16/33) and 72.0% (18/25), respectively; and those of high-definition MRI examination were 83.3% (30/36), 76.5% (13/17) and 89.5% (17/19), respectively. Kappa test showed that the consistency of pathology and pelvic examination and high-definition MRI examination assessments was good in evaluating vaginal invasion (Kappa＝0.297, 0.664; P＝0.002, 0.001). For parametrial invasion, the accuracy, sensitivity and specificity of pelvic examination were 79.8% (75/94), 20.0% (1/5) and 83.1% (74/89), respectively; those of conventional MRI examination were 74.1% (43/58), 31.2% (5/16) and 90.5% (38/42), respectively; and those of high-definition MRI examination were 86.1% (31/36), 60.0% (6/10) and 96.1% (25/26), respectively. Kappa test showed that the consistency of pathology and conventional MRI examination and high-definition MRI examination assessments was good in evaluating parametrial invasion (Kappa＝0.251, 0.618; P＝0.040, 0.001). Conclusion High-definition MRI examination and pathological examination have a good consistency in preoperative assessment of cervical cancer at stage B-ⅡB, and can be a common method for preoperative evaluation of cervical cancer.