Magnetic Resonance in Medical Sciences

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.

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.

Characteristics of MR Imaging for Staging and Survival Analysis of Neuroendocrine Carcinoma of the Endometrium: A Multicenter Study in Japan

This study aimed to examine MRI features and staging of neuroendocrine carcinoma (NEC) of the endometrium and evaluate survival. Clinical data, pathological, and preoperative pelvic MRI findings in 22 patients with histologically surgery-proven endometrial NEC were retrospectively reviewed. Tumors were pure NEC (n = 10) or mixed histotype (n = 12), with 13 large and nine small cell type. International Federation of Gynecology and Obstetrics (FIGO) staging was I, II, III, and IV in 6, 2, 12, and 2 patients, respectively. In 13 (76.4%) of 17 patients with pathological deep myometrial invasion, MRI showed abnormal diffusely infiltrative high T Abnormal diffusely infiltrative high T

Lobular Endocervical Glandular Hyperplasia and Related Glandular Disorders: Current Status of Diagnosis with MR Imaging

Lobular endocervical glandular hyperplasia (LEGH) is a rare benign lesion of the uterine cervix that produces gastric-type mucin. First identified in 1999, LEGH is often misdiagnosed as other glandular lesions, including adenocarcinoma, human papillomavirus (HPV)-independent, gastric-type (GAS), due to similar histopathological features. LEGH is now recognized as a precursor to GAS, a malignancy with poor prognosis. This review explores LEGH's pathological and immunohistochemical characteristics and related glandular lesions, focusing on diagnostic approaches using MRI. MRI has proven essential in distinguishing LEGH from other benign cervical cystic lesions and detecting precursor conditions, such as atypical LEGH, before progression to GAS. A hallmark MRI finding for LEGH is the "cosmos pattern," featuring centrally clustered microcysts surrounded by macrocysts, achieving 95.5% specificity when combined with T1-weighted imaging. Cytology and biopsy improve diagnostic accuracy when imaging results are inconclusive, though obtaining high-quality specimens can be challenging due to lesion location. This article reviews cytological findings, the presence of gastric-type mucin, and MRI features useful for differentiating LEGH from benign non-LEGH lesions, as well as for diagnosing precancerous and malignant conditions. Recent advances in research have led to the recognition that GAS is primarily a solid rather than a cystic lesion, contributing to improved diagnostic accuracy of MRI for GAS. However, some GAS cases and atypical LEGH can still exhibit a cosmos pattern on MRI, similar to LEGH, making differentiation challenging. Therefore, we also discuss a diagnostic strategy integrating MRI findings with cytology and presence or absence of gastric-type mucin.

Microcystic, Elongated and Fragmented Pattern Invasion Can Adversely Influence Preoperative Staging for Low-grade Endometrial Carcinoma

To investigate the influence of microcystic, elongated and fragmented (MELF) pattern invasion on preoperative evaluation of lymph node (LN) metastasis and myometrial invasion in patients with low-grade endometrial carcinoma. The study included 192 consecutive patients with low-grade endometrial carcinoma who underwent preoperative computed tomography (CT) and magnetic resonance imaging (MRI), followed by surgery. One hundred sixty one of 192 patients underwent LN dissection and were analyzed for LN metastasis. All patients were analyzed for myometrial invasion. Presence of enlarged LN was evaluated by using size criteria on CT. Depth of myometrial invasion was evaluated on MRI using T MELF pattern invasion was identified in 43/192 patients (22%). LN metastases were observed in 18/39 patients in MELF group and 6/122 patients in non-MELF group for pelvic LN and 11/29 patients in MELF group and 4/57 patients in non-MELF group for para-aortic LN. Sensitivity for the detection of pelvic LN metastasis in MELF group was significantly lower than in non-MELF group (16.7% vs 66.7%). As for the assessment of the deep myometiral invasion, pathological deep myometrial invasion were found in 31/43 patients in MELF group and 32/149 patients in non-MELF group. Sensitivity in MELF group showed lower values than in non-MELF group (54.8% vs 78.1% for reader 1, 54.8% vs 62.5% for reader 2), although there was no statistically significant difference (P = 0.09 for reader 1 and P = 0.72 for reader 2). In case of low-grade endometrial carcinoma with MELF pattern invasion, preoperative staging by CT and MRI have a risk for underestimation.

Comparing Characteristics of Pelvic High-grade Serous Carcinomas with and without Breast Cancer Gene Variants on MR Imaging

To compare MRI findings of high-grade serous carcinoma (HGSC) with and without breast cancer (BRCA) gene variants to explore the feasibility of MRI as a genetic predictor. We retrospectively reviewed MRI data from 16 patients with BRCA variant-positive (11 patients of BRCA1 and 5 patients of BRCA2 variant-positive) and 32 patients with BRCA variant-negative HGSCs and evaluated tumor size, appearance, nature of solid components, apparent diffusion coefficient (ADC) value, time-intensity curve, several dynamic contrast-enhanced curve descriptors, and nature of peritoneal metastasis. Age, primary site, tumor stage, bilaterality, presence of lymph node metastasis, presence of peritoneal metastasis, and tumor markers were also compared between the groups with the Mann-Whitney U and chi-square tests. The mean tumor size of BRCA variant-positive HGSCs was 9.6 cm, and that of variant-negative HGSCs was 6.8 cm, with no significant difference (P = 0.241). No significant difference was found between BRCA variant-positive and negative HGSCs in other evaluated factors, except for age (mean age, 53 years old; range, 32-78 years old for BRCA variant-positive and mean age, 61 years old; range, 44-80 years old for BRCA variant-negative, P = 0.033). Comparing BRCA1 variant-positive and BRCA2 variant-positive HGSCs, BRCA1 variant-positive HGSCs were larger (P = 0.040), had greater Max enhancement (P = 0.013), Area under the curve (P = 0.013), and CA125 (P = 0.038), and had a higher frequency of lymph node metastasis (P = 0.049), with significance. There was no significant difference in the MRI findings between patients with HGSCs with and without BRCA variants. Although studied in small numbers, BRCA1 variant-positive HGSCs were larger and more enhanced than BRCA2 variant-positive HGSCs with higher CA125 and more frequent lymph node metastases, and may represent more aggressive features.

Endometrial Cancer: A Daily Clinical Practice Guide for Radiologists

Endometrial cancer (EC) is projected to become the third most common cancer and the fourth leading cause of cancer-related deaths among women by 2040, with the most substantial increases observed in non-Hispanic Black, Hispanic, and Asian populations. The International Federation of Gynecology and Obstetrics (FIGO) 2023 classification introduces key updates, including a refined staging system incorporating molecular markers for improved risk stratification. MRI plays a critical role in treatment planning by evaluating the extent of the disease, determining eligibility for fertility-preserving options, guiding radiotherapy planning, and supporting follow-up care. It is also essential for distinguishing EC from cervical cancer. Notable revisions in the FIGO 2023 staging guidelines focus on assessing myometrial invasion, identifying synchronous or metastatic ovarian tumors, and evaluating peritoneal involvement. Recurrence typically occurs within the first 2 years, with common sites including the vaginal vault and lymph nodes, where MRI remains the preferred imaging modality. While CT is routinely employed to assess metastatic disease,