Radiology Department, Sohar Hospital, Sohar, Al Batinah North, Oman
Department of Medical Imaging, McMaster University, Hamilton, Canada.
Int J Gynecol Cancer. 2024 Jul 1;34(7):1027-1033. doi: 10.1136/ijgc-2023-005220.
Uterine leiomyomas are the most common benign uterine tumors. They are difficult to distinguish from their malignant counterparts-smooth muscle tumors of unknown malignant potential (STUMP) and leiomyosarcoma. The purpose of this study is to propose and validate the diagnostic accuracy of the MRI-based Oman-Canada Scoring System of Myometrial Masses (OCSSMM) to differentiate uterine leiomyomas from STUMP/leiomyosarcomas.
This is a retrospective study performed at two tertiary care centers. All patients with a pathology-proven uterine mass who underwent pre-operative pelvic MRI between January 2010 and January 2020 were included. Using a 1.5T MRI machine, sequences included were axial/coronal/sagittal T2 and T1 weighted imaging, axial diffusion weighted and apparent diffusion coefficient map, and axial or sagittal dynamic contrast-enhanced sequences. A scoring system was designed based on previously published worrisome MRI features for uterine leiomyosarcoma. Each feature was allocated a score from 0 to 2 according to the strength of association with malignancy. Subsequently, the MR images were blindly and independently reviewed by a fellowship-trained radiologist and a clinical fellow/senior resident. Each uterine mass was scored according to their imaging features. The scores were divided into five categories according to the sum of scores. Category III and above was considered positive for leiomyosarcoma/STUMP. Sensitivity, specificity, and positive and negative predictive values were calculated.
A total of 244 women were included (age range 20-74 years, mean 40). Of these, 218 patients had benign leiomyoma, 13 had STUMP, and 13 had leiomyosarcoma. The sensitivity and specificity of the scoring system were 92.3% and 64.7%, respectively. The negative predictive value was 98.6%. No leiomyosarcoma was missed using this scoring system. The presence of non-cystic T2 hyperintensity or diffusion restriction in a uterine mass were the most sensitive signs of a leiomyosarcoma/STUMP.
The proposed multi-parametric MRI scoring system may be useful in differentiating benign uterine leiomyomas from leiomyosarcomas/STUMP.
子宫肌瘤是最常见的良性子宫肿瘤。它们很难与恶性肿瘤（平滑肌肿瘤，性质不明，具有潜在恶性，STUMP）和平滑肌肉瘤相区分。本研究旨在提出并验证基于磁共振成像的阿曼-加拿大子宫肿块评分系统（OCSSMM）在区分子宫肌瘤和 STUMP/平滑肌肉瘤中的诊断准确性。
这是一项在两个三级医疗中心进行的回顾性研究。所有经病理证实的子宫肿块患者，在 2010 年 1 月至 2020 年 1 月期间均接受盆腔 MRI 术前检查。使用 1.5T MRI 机器，采集序列包括轴位/冠状位/矢状位 T2 和 T1 加权成像、轴位弥散加权和表观弥散系数图，以及轴位或矢状位动态对比增强序列。基于已发表的与子宫平滑肌肉瘤相关的令人担忧的 MRI 特征，设计了一个评分系统。根据与恶性肿瘤的关联强度，为每个特征分配 0-2 分。随后，由经过专业培训的放射科医生和临床研究员/高级住院医师对 MR 图像进行盲法和独立审查。根据其影像学特征对每个子宫肿块进行评分。根据总分将评分分为五类。类别 III 及以上被认为是平滑肌肉瘤/STUMP 的阳性结果。计算敏感性、特异性、阳性和阴性预测值。
共纳入 244 名女性（年龄 20-74 岁，平均 40 岁）。其中，218 例为良性子宫肌瘤，13 例为 STUMP，13 例为平滑肌肉瘤。该评分系统的敏感性和特异性分别为 92.3%和 64.7%，阴性预测值为 98.6%。该评分系统未漏诊平滑肌肉瘤。子宫肿块中存在非囊性 T2 高信号或弥散受限是平滑肌肉瘤/STUMP 的最敏感征象。
提出的多参数 MRI 评分系统可能有助于区分良性子宫平滑肌瘤和平滑肌肉瘤/STUMP。
