Takashi Yoshiura

Oscillating Gradient Diffusion‐Weighted MRI for Risk Stratification of Uterine Endometrial Cancer

BackgroundOscillating gradient diffusion‐weighted imaging (DWI) enables elucidation of microstructural characteristics in cancers; however, there are limited data to evaluate its utility in patients with endometrial cancer.PurposeTo investigate the utility of oscillating gradient DWI for risk stratification in patients with uterine endometrial cancer compared with conventional pulsed gradient DWI.Study TypeRetrospective.SubjectsSixty‐three women (mean age: 58 [range: 32–85] years) with endometrial cancer.Field Strength/Sequence3 T MRI including DWI using oscillating gradient spin‐echo (OGSE) and pulsed gradient spin‐echo (PGSE) research sequences.AssessmentMean value of the apparent diffusion coefficient (ADC) values for OGSE (ADCOGSE) and PGSE (ADCPGSE) as well as the ADC ratio (ADCOGSE/ADCPGSE) within endometrial cancer were measured using regions of interest. Prognostic factors (histological grade, deep myometrial invasion, lymphovascular invasion, International Federation of Gynecology and Obstetrics [FIGO] stage, and prognostic risk classification) were tabulated.Statistical TestsInterobserver agreement was analyzed by calculating the intraclass correlation coefficient. The associations of ADCOGSE, ADCPGSE, and ADCOGSE/ADCPGSE with prognostic factors were examined using the Kendall rank correlation coefficient, Mann–Whitney U test, and receiver operating characteristic (ROC) curve. A P value of <0.05 was statistically significant.ResultsCompared with ADCOGSE and ADCPGSE, ADCOGSE/ADCPGSE was significantly and strongly correlated with histological grade (observer 1, τ = 0.563; observer 2, τ = 0.456), FIGO stage (observer 1, τ = 0.354; observer 2, τ = 0.324), and prognostic risk classification (observer 1, τ = 0.456; observer 2, τ = 0.385). The area under the ROC curves of ADCOGSE/ADCPGSE for histological grade (observer 1, 0.92, 95% confidence intervals [CIs]: 0.83–0.98; observer 2, 0.84, 95% CI: 0.73–0.92) and prognostic risk (observer 1, 0.80, 95% CI: 0.68–0.89; observer 2, 0.76, 95% CI: 0.63–0.86) were significantly higher than that of ADCOGSE and ADCPGSE.Data ConclusionThe ADC ratio obtained via oscillating gradient and pulsed gradient DWIs might be useful imaging biomarkers for risk stratification in patients with endometrial cancer.Level of Evidence3Technical EfficacyStage 2

Segmental Renal Infarction Associated with Accessory Renal Arteries After Para-Aortic Lymphadenectomy in Gynecologic Malignancies

Background and Objectives: The causes and clinical outcomes of renal perfusion abnormalities occurring after para-aortic lymphadenectomy (PANDx) for gynecologic malignancies are unknown. We investigated the potential involvement of accessory renal artery (ARA) obstruction in their development by reassessing perioperative contrast-enhanced computed tomography (CECT). Materials and Methods: This retrospective study investigated a clinical database to identify urinary contrast defects using CECT in all patients who had undergone PANDx between January 2020 and December 2024. The perfusion defects in the kidney detected by CECT were extracted by a gynecologic oncologist and evaluated by a radiologist and urologist for suspected obstruction of ARAs. Results: Postoperative renal contrast defects were observed in 3.8% (6/157) of patients. Renal parenchymal fibrosis, cortical atrophy, and parenchymal thinning were observed as universal findings in all patients showing renal contrast defects. In five of the six cases, ARAs supplying the infarcted renal segments were identified on preoperative CECT, and arterial obstruction was confirmed on postoperative imaging. The remaining case was considered to be latent pyelonephritis. All five patients underwent laparotomy, and preoperative CECT failed to detect ARAs. The median resected para-aortic lymph node was 23 nodes (range: 15–33) in five patients, showing no statistically significant difference compared to patients without perfusion abnormalities (p = 0.19). Postoperative serum creatinine levels remained stable. Conclusions: ARA obstruction appears to be a risk factor for segmental renal infarction after para-aortic lymphadenectomy in gynecological malignancies; however, the clinical impact on urinary function may be limited. Awareness of this potential complication is essential for gynecologic oncologists performing PANDx.