Kransdorf Mark J, Bancroft Laura W, Peterson Jeffrey J, Murphey Mark D, Foster William C, Temple H Thomas
Department of Radiology, Mayo Clinic, 4500 San Pablo Rd, Jacksonville, FL 32224-3899, USA.
Radiology. 2002 Jul;224(1):99-104. doi: 10.1148/radiol.2241011113.
To review the reliability of computed tomographic (CT) and magnetic resonance (MR) imaging features in distinguishing lipoma and well-differentiated liposarcoma.
CT (n= 29) and MR (n = 40) images and radiographs (n = 28) of 60 patients with histologically verified fatty tumors (35 lipomas and 25 well-differentiated liposarcomas) were retrospectively reviewed in 31 females and 29 males (mean age, 56 years; age range, 1-88 years). Images were assessed for adipose tissue content, and non-fatty component was classified (thin and/or thick septa and nodular and/or globular components) as absent, mild, moderate, or pronounced. Also assessed were signal intensity and tissue attenuation of the fatty components and non-adipose elements.
Statistically significant imaging features favoring a diagnosis of liposarcoma included lesion larger than 10 cm (P <.001), presence of thick septa (P =.001), presence of globular and/or nodular non-adipose areas (P =.003) or masses (P =.001), and lesion less than 75% fat (P <.001). The most statistically significant radiologic predictors of malignancy were male sex, presence of thick septa, and associated non-adipose masses, which increased the likelihood of malignancy by 13-, nine-, and 32-fold, respectively. Both lipoma and liposarcoma demonstrated thin septa and regions of increased signal intensity on fluid-sensitive MR images.
A significant number of lipomas will have prominent non-adipose areas and will demonstrate an imaging appearance traditionally ascribed to well-differentiated liposarcoma. Features that suggest malignancy include increased patient age, large lesion size, presence of thick septa, presence of nodular and/or globular or non-adipose mass-like areas, and decreased percentage of fat composition.
回顾计算机断层扫描（CT）和磁共振成像（MR）特征在鉴别脂肪瘤和高分化脂肪肉瘤中的可靠性。
回顾性分析60例经组织学证实的脂肪性肿瘤（35例脂肪瘤和25例高分化脂肪肉瘤）患者的CT（n = 29）、MR（n = 40）图像及X线片（n = 28），其中女性31例，男性29例（平均年龄56岁；年龄范围1 - 88岁）。评估图像中的脂肪组织含量，非脂肪成分（薄和/或厚间隔以及结节状和/或球状成分）分为无、轻度、中度或明显。还评估了脂肪成分和非脂肪成分的信号强度及组织衰减。
支持脂肪肉瘤诊断的具有统计学意义的影像特征包括病变大于10 cm（P <.001）、存在厚间隔（P =.001）、存在球状和/或结节状非脂肪区域（P =.003）或肿块（P =.001）以及病变脂肪含量低于75%（P <.001）。最具统计学意义的恶性肿瘤影像学预测指标为男性、存在厚间隔以及相关的非脂肪肿块，其使恶性肿瘤的可能性分别增加了13倍、9倍和32倍。脂肪瘤和脂肪肉瘤在液体敏感的MR图像上均表现为薄间隔和信号强度增加的区域。
大量脂肪瘤会有明显的非脂肪区域，并呈现出传统上归因于高分化脂肪肉瘤的影像表现。提示恶性的特征包括患者年龄增加、病变较大、存在厚间隔、存在结节状和/或球状或非脂肪肿块样区域以及脂肪成分百分比降低。
