Multiparametric Magnetic Resonance Imaging in Determining Prognostic Factors for Cervical Cancer IB2-IIB Stages after Neoadjuvant Chemotherapy

Abstract

Background : Comprehensive treatment of locally advanced cervical cancer (CC) requires the use of informative diagnostic methods to assess tumor size, extent of the tumor and other factors that determine prognosis of the disease. Purpose : Determination of diagnostic opportunities of multiparametric magnetic resonance imaging (mpMRI) in the visualization of residual tumor and assessment of the main prognostic factors in patients with stage IB2-IIB cervical cancer (FIGO) after neoadjuvant chemotherapy (NACT). Material and methods : Patients with stage IB2-IIB cervical cancer (n = 120) were prospectively enrolled in the study; they received NACT followed by surgical treatment or chemoradiotherapy (CRT). Patients underwent mpMRI before NACT and not later than 14 days after the 3rd course of NACT. To determine the diagnostic opportunities of mpMRI, MRI-data were compared with pathomorphological results. In the comparative analysis were included the following factors: residual tumor size (maximum diameter), depth of stromal invasion (mm), presence of parametrial invasion. Potential MRI-signs suggestive for lymphovascular invasion (LVI) of the parametrium were also assessed. Results : Obtained MRI-data about the size of the residual tumor and the depth of stromal invasion showed statistically significant correlation with the results of pathomorphological study (p < 0.0001) — R 2 = 0.77 and 0.69, respectively. Difference value in measuring the maximum diameter of the residual tumor was on the average 2.52±6.76 mm. MRI sensitivity in the assessment of parametrial invasion was 71.4 %, specificity — 95.1 %, accuracy — 88.9 %, PVPR — 71.4 %, PVNR — 95.1 %. Potential predictors significantly associated with parametrial LVI were identified: parametrial edema (p = 0.001) and dilatation of parametrial vessels (> 3 mm) (p = 0.015). According to these factors was developed a mathematical model, which predicts the risk of having parametrial LVI before surgery in patients after NACT. Conclusion : Multiparametric MRI is an effective technique in assessing the size of the residual tumor, depth of stromal invasion and parametrial invasion in patients with stage IB2-IIB cervical cancer after NACT. MpMRI makes it possible to assess potential signs, associated with parametrial LVI in patients with locally advanced cervical cancer.