The clinical significance of magnetic resonance diffusion-weighted imaging combined with dynamic contrast-enhanced scanning or methylene blue cervical injection in differentiating sentinel lymph node metastasis of early cervical cancer

LIU Le; TANG Yongjun; LIU Qianjin; GUO Jianwei; LI Jixiang

doi:10.3969/j.issn.1009-0460.2025.09.008

Abstract：Objective To compare the clinical value of magnetic resonance diffusion-weighted imaging(DWI)combined with dynamic contrast-enhanced scanning(DCE-MRI)and methylene blue cervical injection in predicting sentinel lymph node(SLN)metastasis of early cervical cancer.Methods A total of 40 patients with stage IA2 to IIA of early cervical cancer who were admitted to the First Affiliated Hospital of Shaoyang University from January 2023 to February 2025 were prospectively included.All patients underwent radical hysterectomy and systematic pelvic lymph node dissection.Before the operation,they all underwent multi-parameter magnetic resonance examinations,including DCE-MRI and DWI,and methylene blue was injected into the cervix for SLN tracing.Results Intraoperative pathological biopsy of SLN showed that 8 cases(20.0%)of patients were SLN positive(SLN+group),and the remaining 32 cases were SLN negative(SLN-group).Eight cases(20.0%)of SLN positive patients were identified by methylene blue tracing,including 6 cases with positive intraoperative biopsy and 2 cases with negative biopsy.Univariate and multivariate analyses showed that tumor diameter>2.0 cm(OR=37.800,P=0.002),lymph node diameter>10 mm(OR=7.222,P=0.021),and heterogeneous enhancement within the mass(OR=25.000,P=0.005),the ratio of the minimum ADC value to the intratumoral ADC(OR=1.134,P=0.037),and lymphovascular space infiltration(OR=5.400,P=0.049)were influencing factors for SLN metastasis.The area under the curve(AUC)of the receiver operating characteristic(ROC)curve model constructed based on the heterogeneity characteristics of internal signals and the minimum ADC/intratumoral ADC ratio in DCE-MRI for predicting SLN metastasis was 0.896,with a specificity of 100.0%and a sensitivity of 75.0%.Consistency analysis showed that the diagnosis of SLN metastasis by DCE-MRI combined with DWI was highly consistent with the pathological diagnosis results(kappa=0.918,P<0.001;sensitivity 100.0%,specificity 96.97%,accuracy 97.50%).The sensitivity and specificity of methylene blue tracer in diagnosing SLN metastasis were 75.0%and 93.75%respectively,the accuracy was 90.0%,and the consistency was moderate(kappa=0.688,P<0.001).Conclusion DCE-MRI combined with DWI shows good diagnostic performance in preoperative prediction of SLN metastasis in early cervical cancer,has high consistency with pathological diagnosis,and has higher sensitivity and accuracy compared with methylene blue tracer.