Miki Yoshida

Comparison of MR Imaging of High-grade Serous Carcinomas with and without Homologous Recombination-deficiency

MRI findings of high-grade serous carcinoma (HGSC) with and without homologous recombination deficiency (HRD) were compared to explore the feasibility of using MRI as a genetic predictor. We retrospectively reviewed MRI data from HRD-positive and HRD-negative HGSC and evaluated tumor size, appearance, apparent diffusion coefficient (ADC), time-intensity curve, and several dynamic contrast-enhanced curve descriptors. Age, primary site, tumor stage, bilaterality, presence of lymph node metastasis, presence of peritoneal metastasis, and tumor marker levels were also compared. Forty-eight patients with HRD-positive HGSC (17 patients with BRCA1 variant, 9 patients with BRCA2 variant, and 22 without BRCA variants) and 18 patients with HRD-negative HGSC were included. The HRD-negative patients' mean age was 67 years, which was significantly higher than that of the HRDpositive patients (60 years, P = 0.011). High-risk time-intensity curve (TIC) patterns were more common in HRD-negative tumors (94%) than in HRD-positive tumors (63%; P = 0.047). Tumors without HRD exhibited significantly higher wash-in rates (P = 0.023). Additionally, unresectable lymph node metastases were significantly more frequent in HRD-negative patients (P = 0.013). No significant differences were observed in the other evaluated factors. The comparison between HGSC with and without HRD revealed that HGSC without HRD was significantly associated with older age, a higher likelihood of exhibiting a high-risk TIC pattern, a higher wash-in rate, and a higher frequency of unresectable lymph node metastasis.

Comparison of Benign, Borderline, and Malignant Ovarian Seromucinous Neoplasms on MR Imaging

This study aimed to compare MRI findings among benign, borderline, and malignant ovarian seromucinous neoplasms. We retrospectively analyzed MRI data from 24 patients with ovarian seromucinous neoplasms-seven benign, thirteen borderline, and six malignant. The parameters evaluated included age, tumour size, morphology, number, height, apparent diffusion coefficient (ADC) values, T2 ratios, time-intensity curve (TIC) descriptors, and TIC patterns of the mural nodules. Additionally, we examined the T2 and T1 ratios of the cyst contents, tumour markers, and the presence of endometriosis. We used statistical tests, including the Kruskal-Wallis and Fisher-Freeman-Halton exact tests, to compare these parameters among the three aforementioned groups. The cases showed papillary architecture with internal branching in 57% of benign, 92% of borderline, and 17% of malignant cases. Three or fewer mural nodules were seen in 57% of benign, 8% of borderline, and 17% of malignant cases. Compared to benign and borderline tumours, mural nodules of malignant neoplasms had significantly increased height (P = 0.015 and 0.011, respectively), lower means ADC values (P = 0.003 and 0.035, respectively). The mural nodules in malignant cases also demonstrated significantly lower T2 ratios than those in the benign cases (P = 0.045). Most neoplasms displayed an intermediate-risk TIC pattern, including 80% benign, 83% borderline, and 60% malignant neoplasms, and no significant differences were observed. Most benign and borderline tumours exhibited a papillary architecture with an internal branching pattern, whereas this feature was less common in malignant neoplasms. Additionally, benign tumours had fewer mural nodules compared to borderline tumours. Malignant neoplasms were characterized by mural nodules with increased height and lower ADC values than those in benign and borderline tumours. Interestingly, all three groups predominantly exhibited an intermediate-risk TIC pattern, emphasizing the complexity of diagnosing seromucinous neoplasms using MRI.

Assessment of the utility of intravoxel incoherent motion and diffusion kurtosis imaging for determining eligibility for fertility preservation

Background Accurate preoperative assessment of endometrial cancer (EC) is crucial in young women who may be eligible for fertility-preserving therapy, which is generally limited to patients with grade 1, endometrioid-type tumors without myometrial invasion (MI). Purpose To evaluate the utility of quantitative parameters derived from intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) for improving the diagnostic performance of magnetic resonance imaging (MRI). Material and Methods This retrospective study included 107 patients diagnosed with EC (mean age = 59 years; age range = 25–89 years) who underwent preoperative MRI, including multiple b-value (0–2000 s/mm 2 ) diffusion-weighted imaging, between January 2022 and March 2024. Quantitative parameters were extracted from the mono-exponential (ADC), IVIM (Di, D*, f), and DKI (Dk, K) models and compared across clinical and pathological features. Results ADC, Di, and Dk values were significantly higher in patients without MI ( P  = 0.015, 0.035, and 0.005, respectively). Di and Dk were significantly higher ( P  = 0.003 and 0.016), and K was significantly lower ( P  = 0.013) in the G1 group. Patients eligible for fertility preservation had significantly higher ADC, Di, and Dk values ( P  = 0.002, 0.002, and 0.001) and significantly lower K values ( P  = 0.044). The overall diagnostic performance of these parameters was moderate (area under the curve < 0.70). Conclusion IVIM and DKI-derived metrics may enhance preoperative assessment of tumor grade and MI, supporting decisions regarding fertility-preserving treatment.

The Utility of Apparent Water Diffusion Coefficient Maps for Evaluating the Presence of Myometrial Invasion in Patients with Endometrial Cancer

To assess the utility of apparent diffusion coefficient maps (ADC) for diagnosing myometrial invasion (MI) in endometrial cancer (EC). This retrospective study included 164 patients (mean age, 56 years; range, 25-89 years) who underwent preoperative MRI for EC with <1/2 MI or no MI between April 2016 and July 2023. Five sequences were evaluated: T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), ADC, dynamic contrast-enhanced T1-weighted imaging (DCE-T1WI), and contrast-enhanced T1WI (CE-T1WI). Three experienced radiologists independently assessed the sequences for MI. For ADC, MI was determined if the endometrial-myometrial junction-tumor boundary had disappeared. Additionally, the assessment of MI was performed using the combination of T2WI, DWI, and ADC, as well as T2WI, DCE-T1WI, and CE-T1WI. The sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUC) for the presence of MI were calculated and compared between the sequences and combinations. Inter-reader agreement was assessed using kappa (κ) statistics. The sensitivity of ADC was significantly higher than T2WI (P < 0.001) and DCE-T1WI (P = 0.018) for one reader and significantly higher than CE-T1WI (P = 0.045 and 0.043) for two readers. The specificity of ADC was significantly lower than T2WI (P = 0.015 and < 0.001) and CE-T1WI (P = 0.031 and 0.01) for two readers and significantly lower than DCE-T1WI (P = 0.031) for one reader. The AUC of ADC was significantly higher than T2WI (P = 0.048) and DCE-T1WI (P = 0.049) for one reader. The combination including ADC showed higher positive predictive value for all three readers compared to any sequence or combination including contrast enhancement. Additionally, ADC demonstrated the highest agreement rates. ADC had high sensitivity for MI and the highest agreement rate among all sequences. Thus, this sequence, combined with other sequences, can be crucial for a comprehensive evaluation of MI.