The performance of DWI and ADC values with different b-values for the diagnosis and staging of endometrial carcinoma at 3T.

OBJECTIVE: To evaluate the efficiency of diffusion weighted imaging (DWI), the mean apparent diffusion coefficient (ADCmean) and the minimum apparent diffusion coefficient (ADCmin) values with different b-values (800 s/mm² and 1000 s/mm²) in the diagnosis and staging of endometrial carcinoma (EC). METHODS: Preoperative DWI images of 412 patients with EC and 134 patients with benign endometrial lesions were analyzed retrospectively. The performance of DWI images, ADCmean and ADCmin values with different b-values (800 s/mm² and 1000 s/mm²) for the diagnosis and staging (deep myometrial invasion, cervical stromal invasion and lymph node metastasis) of EC was assessed by using receiver operating characteristic curve (ROC). The comparison between AUCs was performed using the DeLong test, and a P value < 0.05 was considered statistically significant. RESULTS: The area under the curves (AUCs) of DWI protocol with b = 1000 s/mm2 for qualitative assessment of EC diagnosis and staging (0.850, 0.837, 0.906, and 0.820 for diagnosis, deep myometrial invasion, cervical stromal invasion and lymph node metastasis, respectively) were higher than those of b = 800 s/mm2 (0.821, 0.795, 0.860 and 0.814, respectively) (all p < 0.05). The AUCs for the quantitative assessment of EC diagnosis and staging with ADCmean and ADCmin values with b = 1000 s/mm2 were higher than those of b = 800 s/mm2 (all p < 0.05). CONCLUSIONS: DWI images, ADCmean and ADCmin values with b = 1000 s/mm2 had higher performance than those of b = 800 s/mm2 in the assessment of EC diagnosis and staging. This study highlights the potential of using b = 1000 s/mm² as an optimized protocol for EC assessment in clinical practice.