Multi-b-value diffusion-weighted imaging-derived parameters for differentiating high-grade serous ovarian carcinoma from other epithelial ovarian cancers.

OBJECTIVE

High-grade serous carcinoma (HGSC) is the most common ovarian cancer subtype, and its differentiation from others is crucial for treatment. This study aimed to evaluate parameters derived from multi-b-value diffusion-weighted imaging (DWI), including apparent diffusion coefficient (ADC), and metrics based on intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI), for differentiating HGSC from other ovarian cancers.

METHODS

We retrospectively analysed patients with primary epithelial ovarian cancer who underwent preoperative MRI including multi-b-value DWI. From the solid tissues of the tumours, diffusion parameters were derived from the multi-b-value DWI data using different models: ADC using a mono-exponential model; the true diffusion coefficient (Di), pseudo-diffusion coefficient (D*), and perfusion fraction (f) using the IVIM model; and kurtosis (K) using the DKI model.

RESULTS

This study included 56 patients with different histological cancer subtypes (mean age, 60 years; range, 24-87 years). The mean values of HGSC compared to the other cancers showed lower ADC (0.58 ± 0.21 × 10⁻ mm/s vs. 0.76 ± 0.18 × 10⁻ mm/s, p < 0.001), lower Di (0.37 ± 0.09 × 10⁻ mm/s vs. 0.42 ± 0.15 × 10⁻ mm/s, p = 0.201), and lower f (35.79 ± 11.48% vs. 48.01 ± 17.21%, p = 0.003), with a higher K (1.06 ± 0.25 vs. 0.84 ± 0.20, p = 0.341). Among these parameters, ADC showed the highest diagnostic performance in differentiating HGSC from others, with an area under the receiver operating characteristic curve of 0.79. These trends were particularly pronounced between HGSC and clear cell carcinoma, with significant differences in all parameters except D*. Additionally, K was the only parameter that showed a significant difference between HGSC and endometrioid carcinoma.

CONCLUSION

Multi-b-value DWI-derived parameters, particularly ADC, may aid in the non-invasive preoperative differentiation of HGSC from other ovarian cancers. Multi-b-value DWI-derived parameters, especially ADC, demonstrated utility in differentiating high-grade serous carcinoma (HGSC) from other ovarian cancers, highlighting their potential in non-invasive preoperative tumor characterization.