The Value of Diffusion-Weighted Magnetic Resonance Imaging in Assessing the Response of Locally Advanced Cervical Cancer to Neoadjuvant Chemotherapy

Abstract

The objective of this study was to investigate whether magnetic resonance diffusion-weighted imaging (DWI) of locally advanced cervical cancer (LACC) both in the sagittal and axial planes could be used to assess the response of LACC to neoadjuvant chemotherapy (NACT). Thirty women with LACC received conventional magnetic resonance imaging and DWI at 3 different times (before NACT, 2 weeks after the first NACT, and 2 weeks after the second NACT). Treatment response was determined according to the change in tumor size 2 weeks after the second NACT, and they were classified as the effective group and the ineffective group. The apparent diffusion coefficients (ADCs) were compared between 2 imaging planes, and dynamic changes in ADCs were observed in different chemotherapy-sensitive groups and imaging planes. One-way analysis of variance was calculated between those ADC parameters and tumor response. The effective chemotherapy rate was 76.67%. Apparent diffusion coefficient values of the axial plane at 3 different times were 0.88 (SD, 0.08) × 10⁻³ mm²/s, 0.96 (SD, 0.10) × 10⁻³ mm²/s, and 1.19 (SD, 0.11) × 10⁻³ mm²/s, respectively. Meanwhile, ADC values of the sagittal planes were 0.89 (SD, 0.09) × 10⁻³ mm²/s, 0.97 (SD, 0.12) × 10⁻³ mm²/s, and 1.19 (SD, 0.12) × 10⁻³ mm²/s at 3 different stages. There were no statistical differences between the ADC values of the 2 planes at 3 different times (P = 0.927, P = 0.863, P = 0.946). Apparent diffusion coefficients 2 weeks after the first NACT were significantly increased compared with those before chemotherapy both in the axial and sagittal planes (P = 0.003, P = 0.012). In the ineffective group, ADCs 2 weeks after the first NACT were not statistically higher than those before chemotherapy (axial planes, P = 0.694; sagittal planes, P = 0.900). After 2 weeks of the first NACT, ADCs in both planes were obviously increased in the effective group than those in the ineffective group (P = 0.043, P = 0.022). The axial and sagittal DWI may detect the changes in LACC after therapy. Apparent diffusion coefficient values measured both in the 2 planes may be used to evaluate the response of LACC to NACT.