【双语病例】?腹膜后平滑肌肉瘤 Retroperitoneal sarcoma (leiomyosarcoma)

History and CT images 疾病史和CT影像图

An 85-year-old woman with a history of ruptured abdominal aortic aneurysm (AAA) status post surgical repair now presents with an enlarging abdominal mass and sharp pain. The patient is hemodynamically stable, but labs are notable for severe anemia.

85岁女性，腹主动脉瘤破裂修复术后。发现腹部包块逐渐增大伴锐痛。患者现血流动力学情况稳定，但有严重的贫血。

1、There is recurrent rupture of the repaired aortic aneurysm

腹主动脉瘤修复术后复发破裂

True

False

2、There is a heterogeneous retroperitoneal mass

腹膜后不均质肿块

True

False

3、There is left-sided hydronephrosis

左肾积水

True

False

4、Which of the following is the best next step?

下一步最好采取什么措施？

Ultrasound-guided drain placement for complex collection

超声引导下穿刺引流

Emergent laparotomy for repair of recurrent ruptured AAA

急诊剖腹手术修复破裂的腹主动脉瘤

Emergent angiography and endovascular aneurysm repair (EVAR) for recurrent ruptured AAA

急诊动脉造影术及腹主动脉瘤破裂血管腔内修复术

MRI for further characterization of the mass

MRI对肿块进一步定性

MR Images MR图像

MRI is attained for further characterization of the left abdominal mass.

患者行MRI检查以进一步对左腹部包块定性。

In order: T2, T1 postgadolinium, and two T2 images.

5、The mass is predominantly T2 hyperintense.

肿块以T2WI高信号为主

True

False

6、There are enhancing septae within the mass.

肿块内可见强化的分隔

True

False

7、Which of the following is the most likely diagnosis?

下列最有可能的诊断是什么？

Gastrointestinal stromal tumor 胃肠道间质瘤GIST

Retroperitoneal sarcoma 腹膜后肉瘤

Angiomyolipoma 血管平滑肌脂肪瘤AML

Infected aortic aneurysm graft 主动脉瘤移植片感染

Lymphoma 淋巴瘤

8、Which of the following is the most common retroperitoneal sarcoma?

腹膜后肿瘤最常见的是下列哪种？

Liposarcoma 脂肪肉瘤

Leiomyosarcoma 平滑肌肉瘤

Fibrosarcoma 纤维肉瘤

Rhabdomyosarcoma 横纹肌肉瘤

9、MRI features are sufficient to distinguish between sarcoma subtypes and, therefore, biospy is typically not required.

该病的MRI征象已经非常明确，足以区分肉瘤的亚型，通常不需要活检。

True

False

10、The patient underwent surgical debulking, and surgical pathology confirmed high-grade leiomyosarcoma. Which vascular structure is most often involved in retroperitoneal leiomyosarcoma?

该患者行外科减瘤术，手术病理证实为高级别平滑肌肉瘤。腹膜后平滑肌肉瘤最易累及下列哪个器官？

Aorta

Inferior vena cava (IVC)

Left renal vein

Superior mesenteric artery

选择题答案：

1. False
   

2. True

3. True

4. MRI for further characterization of the mass

5. True

6. True

7. Retroperitoneal sarcoma

8. Liposarcoma

9. False

10. Inferior vena cava (IVC)

Findings 检查结果

• CT angiogram: There is no evidence of active bleeding from the surgically repaired abdominal aortic aneurysm. There is a large bilobed mass in the left retroperitoneum, the majority of which is cystic/necrotic, with enhancing septae. The mass exerts mass effect on adjacent structures, including the proximal left lumbar ureter, contributing to left hydronephrosis.

  腹主动脉瘤破裂修复术后，未见明显活动性出血。左侧腹膜后可见一巨大分叶状肿块，肿块内可见大片状囊变坏死区，并可见强化的分隔。肿块占位效应明显，左侧输尿管受压，左肾积水。

• MRI: There is a bilobed, heterogeneous cystic mass that is predominantly T2 hyperintense. There is a T2 hypointense region in the anterior superior portion of the mass, corresponding to hemorrhagic material. Postgadolinium image (image 7) demonstrates septal enhancement.

  肿块呈分叶状，信号不均匀，以囊性为主，表现为T2WI高信号。肿块前上部可见T2WI低信号区，为出血。增强扫描可见肿块内分隔强化。

Differential Diagnosis 鉴别诊断

• Retroperitoneal sarcoma

  腹膜后肉瘤

• Gastrointestinal stromal tumor

  胃肠道间质瘤

• Peripheral nerve sheath tumor

  周围神经鞘瘤

• Malignant fibrous histiocytoma

  恶性纤维组织细胞瘤

• Ganglioneuroma

  神经节瘤

• Retroperitoneal hemorrhage

  腹膜后血肿

• Renal angiomyolipoma

  肾血管平滑肌脂肪瘤

Diagnosis 诊断

Retroperitoneal sarcoma (leiomyosarcoma)

腹膜后平滑肌肉瘤

Discussion 讨论

Malignancy of mesodermal origin that arises from smooth muscle cells of vasculature or bowel.

起源于中胚层的恶性肿瘤，多发生于脉管系统或肠道的平滑肌细胞。

• Extravascular 血管外(62%).

• Intravascular 血管内(6%):

  Most commonly arises from IVC.最常发生于下腔静脉。

• Both intravascular and extravascular involvement 血管内外(33%):

  Invades local structures, including solid organs and vasculature.

  可侵犯临近结构，包括实性器官和血管系统。

Pathology 病理学

• Well-differentiated 高分化型

• Pleomorphic 多形型

• Myxoid 粘液型

• Dedifferentiated 未分化型

  
  

Imaging features are nonspecific, and biopsy is usually required for a diagnosis.

影像表现缺乏特异性，定性诊断需要依靠病理活检。

General Features 一般特征

Large retroperitoneal mass, often 10 cm or larger at diagnosis.

腹膜后巨大肿块，发现时常超过10cm。

Imaging findings are nonspecific and vary depending on tumor composition.

影像学表现缺乏特异性，根据肿瘤成分不同，表现也不同：

• Can have large components of cystic necrosis.

  可有大片囊变坏死

• Fat and calcification are typically not present.

  脂肪和钙化少见

CT

• Large retroperitoneal mass with cystic and/or necrotic components

  巨大腹膜后肿块，伴有囊变 和/或 坏死。

• Heterogeneous enhancement

  不均匀强化。

MRI

• T1-weighted images: intermediate to low signal

  T1WI：等至低信号

• T2-weighted images: intermediate to high signal related to water content in cystic/necrotic portions

  T2WI：由于病灶内囊变/坏死而呈等至高信号。

• Postgadolinium: heterogeneous enhancement

  增强扫描：不均匀强化。