脂肪肉瘤-ppt课件

1、.,1,早读片2015-07-31,.,2,女 61岁 Patient ID：41721677,.,3,主 诉：体检发现左侧胸腔占位一月余 入院情况：患者一月前因咳嗽地热于外院查体发现左侧胸腔占位。患者目前无明显不适，无胸闷憋气，无咳嗽咳痰，无胸痛。 入院查体：左肺下叶呼吸音较对侧减弱。 既往史：高血压十余年，药物控制满意。 1971年急性阑尾炎，阑尾切除。,.,4,肿瘤标记物： CA125：41.8U/ml（0-35.0） NSE(神经元特异性烯醇化酶):17.3ng/ml(0-16.3) ProGRP（血清胃泌素释放肽前体）:56.0pg/ml(0-50),.,5,诊断及鉴别诊断,脂肪肉瘤

2、 畸胎瘤,.,6,手术记录,麻醉满意后，患者取右侧卧位，常规消毒，铺巾。取左侧第5肋间外侧切口长约25cm，逐层切开进胸。探查胸腔少量淡黄清亮胸水，胸腔内无粘连，探查上、下肺未见明显异常，探查肿瘤约16*12*10cm大小，质稍软，有包膜，与肺无粘连，根部来源于左侧胸腺并与部分心包粘连紧密界限不清，挤压左侧膈神经，游离纵隔胸膜，显露并游离保护左侧膈神经，打开心包，在心包内游离切除受累及的心包，在肿物与胸腺连接部切断、移除巨大肿瘤。探查胸腺发现胸腺右叶内有直径2cm质硬肿物，累及右侧纵隔胸膜，遂打开右侧纵隔胸膜，保护右侧膈神经，完整切除胸腺及胸腺肿物满意，心包缺损予以涤纶补片修补满意，严密止血后

3、彻底清洗胸腔，在第5、6、7肋间神经靠近神经根处解剖出肋间神经予以冷冻治疗，查胸腔内无渗血，膨左肺满意无漏气。清点纱布、纱垫、器械无误后，放置胸腔引流管一根，逐层关闭胸腔。将患者转为仰卧位，于患者右侧腋前线第6肋间消毒铺巾后放置胸腔闭式引流一根顺利。,.,7,病理结果,.,8,A similar case in the literature,Age：58 years old Sex： Male Symptoms： recent onset of dysphonia, mild dysphagia to solids, dyspnea on exertion and cough,.,9,CT s

4、canning of the neck and chest demonstrating the lipoid mass displacing the trachea, the oesophagus and great vessels without direct invasion,Rena O, Davoli F, Pia F et al. Giant Cervico-mediastinal Well-differentiated Liposarcoma. Heart, lung 24: e112-4.,（well-differentiated liposarcoma ）,.,10,Brief

5、 Introduction,Liposarcoma A malignant tumor derived from primitive or embryonal lipoblastic cells Adult 4050 yrs Extremities，retroperitoneum,.,11,Classification,Histologically, liposarcoma（LS）is divided into five distinct subtypes: Well-differentiated LS Dedifferentiated LS Myxoid LS / Round cell LS

6、 Pleomorphic LS Mixed-type LS,.,12,World Health Organization Classification of Bone and Soft Tissue Tumors: Modifications and Implications for Radiologists Mark D. Murphey, M.D.,.,13,Classification,Histologically, liposarcoma（LS）is divided into five distinct subtypes: Well-differentiated LS Dediffer

7、entiated LS Myxoid LS / Round cell LS Pleomorphic LS Mixed-type LS,.,14,Well-differentiated Liposarcoma（WDLS）,Well-differentiated liposarcoma represents the most common type of liposarcoma, accounting for approximately 50% of lesions. The typical clinical presentation of well-differentiated liposarc

8、oma is that of a painless, slowly enlarging mass. Well-differentiated liposarcomas most frequently affect the deep soft tissue of the extremities (65 to 75% of cases). The retroperitoneum is the second most common location for this lesion, accounting for 20 to 33% of cases.,.,15,Cross-sectional imag

9、ing of well-differentiated liposarcoma is frequently characteristic. CT and MR imaging reveal a lesion composed of 50 to 75% adipose tissue with additional prominent nonlipomatous components . The nonlipomatous components of the lesion commonly reveal thick ( 2 mm) and numerous septa or focal globul

10、ar or nodular regions (typically 2 cm in size). （collagenized areas, metaplastic mineralization, fat necrosis）,Imaging features of WDLS,.,16,Well-differentiated liposarcoma of the distal thigh in a 65-year-old woman. CT , sagittal T1-WI, and sagittal T2-WI MR images show a largely lipomatous soft ti

11、ssue mass (arrows) with prominent nonlipomatous components seen as irregular thick septae and globular regions (arrowheads) typical of well-differentiated liposarcoma.,.,17,For radiologists, Well-differentiated liposarcoma can have an appearance similar to lipoma in 4 to 9% of cases. Ohguri et al1 a

12、nd Hosono et al2 have suggested that prominent contrast enhancement of the septa on MR imaging suggests well-differentiated liposarcoma as opposed to lipoma, which may aid in distinction in these cases. Lipomatous lesions in the retroperitoneal should always be considered a liposarcoma regardless of

13、 the intrinsic imaging appearance 1. Ohguri T, Aoki T, Hisaoka M, et al. Differential diagnosis of benign peripheral lipoma from well-differentiated liposarcoma on MR imaging: is comparison of margins and internal characteristics useful? AJR Am J Roentgenol 2003;180(6):16891697 2. Hosono M, Kobayash

14、i H, Fujimoto R, et al. Septum-like structures in lipoma and liposarcoma: MR imaging and pathologic correlation. Skeletal Radiol 1997;26(3):150154,.,18,Biopsy of extremity lesions is often fraught with uncertainty, owing to the large size and heterogeneity of these lesions and possibility of not obt

15、aining diagnostic tissue to allow differentiation from lipoma. Imaging may be helpful to direct biopsy to more nonlipomatous regions, allowing more confident pathological diagnosis.,What else can radiologists do ?,.,19,Dedifferentiated Liposarcoma(DDLS),Dedifferentiated liposarcoma arises within a w

16、ell-differentiated lesion, representing a biphasic tumor. The nonadipose component is typically a high-grade cellular sarcoma (often MFH or fibrosarcoma).,.,20,Dedifferentiation occurs in 10% of WDLS, and the incidence depends on lesion location. The estimated risk of dedifferentiation for deep-seat

17、ed extremity lesions is 5%. The estimated risk of dedifferentiation in retroperitoneal lesions is 15% and much higher than other locations. （It has been suggested that this higher incidence of dedifferentiation in retroperitoneal tumors is related to the delayed diagnosis at this site and larger siz

18、e at detection as compared with extremity lesions.）,.,21,Imaging features of DDLS,Imaging features correlate with the biphasic nature of this lesion. The largest component has features of well-differentiated liposarcoma, as previously described. In addition, there is a focal nodular nonlipomatous co

19、mponent that is typically larger than 2 to 3 cm in size. nonspecific CT ：similar to muscle T1WI: low to intermediate signal intensity T2WI: intermediate to high signal intensity Diffuse contrast enhancement on MR in the focus of dedifferentiation (Peripheral rim enhancement on postcontrast MR may he

20、lp identify fat necrosis and allow distinction from a region of dedifferentiation),.,22,Coronal T1WI and T2WI MR images reveal a mass largely composed of tissue isointense to subcutaneous fat (arrows) but also containing thick septae (arrowheads). There is also a large nodular nonlipomatous componen

21、t with nonspecific characteristics of low signal intensity on T1WI and heterogeneous intermediate to high signal intensity on T2WI (asterisks).,Dedifferentiated liposarcoma of the thigh in a 72-year-old man with a 10-year history of a slowly enlarging mass with more recent rapid growth.,.,23,For rad

22、iologists,It is vital for radiologists to recognize that any prominent solid nodular focus ( 2 cm) within a well-differentiated liposarcoma should be biopsied because of the concern for dedifferentiation and its implication on treatment and prognosis. In fact, a strong argument can be made that this

23、 distinction is more important for patient management than the distinction of lipoma versus well-differentiated liposarcoma of the extremities.,.,24,Learning Points,Fat-containing lesions in the mediastinum-taking liposarcoma into consideration Provide more imaging information for surgeons in additi

24、on to a simple diagnosis of liposarcoma (e.g. adjacent great vessels /organs, characteristics of nonadipose components ) Contrast-enhanced CT or MRI should be recommended when necessary(e.g. atypical uncertain solid/nonadipose components ),.,25,早读片2015-09-11,.,26,Case Presentation,M 66y Patient ID：4

25、1726258 主诉：体检发现腹膜后肿物5天。 主要症状：患者偶有腹胀，目前无其他不适。 既往史：约7-8年前，因前列腺增生行前列腺电切术，过程顺利。,.,27,病理结果,.,28,.,29,Retroperitoneal Liposarcoma,Liposarcoma is a common type of soft tissue sarcoma, which occurs most commonly in the extremities (52%), followed by the retroperitoneum (19%). CT is the most commonly used mo

26、dality for the diagnosis, staging, and preoperative evaluation of retroperitoneal liposarcomas.,Murphey, M. D. (2007). “World Health Organization classification of bone and soft tissue tumors: modifications and implications for radiologists. Semin Musculoskelet Radiol 11(3): 201-214.,Zhang, W. D., e

27、t al. (2015). Management of retroperitoneal liposarcoma: A case report and review of the literature. Oncol Lett 10(1): 405-409.,.,30,Zhang, W. D., et al. (2015). Management of retroperitoneal liposarcoma: A case report and review of the literature. Oncol Lett 10(1): 405-409.,48 yearold female Abdomi

28、nal pain in the left side for one month, accompanied by abdominal distention following eating. The past medical and surgical history of the patient had no relevance to the case.,.,31,Classification,Histologically, liposarcoma（LS）is divided into five distinct subtypes: Well-differentiated LS Dediffer

29、entiated LS Myxoid LS / Round cell LS Pleomorphic LS Mixed-type LS,.,32,Myxoid Liposarcoma,Myxoid liposarcoma represents 2050% of all liposarcomas and is the second most common subtype Liposarcoma. Myxoid liposarcomas most commonly affect the lower extremity (75 to 80% of lesions) and occur in patie

30、nts approximately a decade younger (fourth and fifth) than other liposarcomas. The clinical presentation is that of a painless, enlarging soft tissue mass that may be quite large ( 15 cm). Myxoid liposarcomas are intermediate-grade lesions ;treated by wide surgical excision, adjuvant chemo-therapy m

31、ay also be employed; an overall 5-year survival rate of 47 to 77%.,.,33,Location: intramuscular of the lower extremities (70 to 80%); General (but nonspecific) imaging manifestation: (based on the high water content of the myxoid component ) low attenuation on CT() low to intermediate signal intensi

32、ty on T1WI(/) very high signal intensity on T2 WI(),Imaging features of Myxoid Liposarcoma,.,34,Imaging features of Myxoid Liposarcoma,Soft tissue mass,“Cyst mimicker “,.,35,Soft tissue mass： 42 to 78% of cases; Its pathognomonic feature by imaging on MRI: the additional detection of an adipose comp

33、onent (usually 5 to 10% of the tumor volume) within the myxoid background;,Imaging features of Myxoid Liposarcoma,.,36,(AC) Sagittal T1WI both (A) before and after (B) contrast and axial T2WI show a large heterogeneous intermuscular popliteal mass (arrows). The predominant signal intensity is that o

34、f a high water content mass with low signal on T1 weighting and high signal on T2 weighting. However, focal areas in the septae and several small nodular regions (arrowheads) ( 10% of the tumor volume) are isointense to subcutaneous fat. Following contrast administration there is thick and nodular p

35、eripheral and septal enhancement most prominent inferiorly.,Myxoid liposarcoma of the popliteal region in a 60-year-old woman with a painless, slowly enlarging mass.,.,37,The incidence of metastases ranges from 35% (5 to 10% round cell component) to 56% (25% round cell component)identification of th

36、ese foci in a myxoid liposarcoma should alert the radiologist to biopsy these regions, to aid in appropriately aggressive preoperative treatment. Metastases from myxoid liposarcoma demonstrates a predilection from nonpulmonary locations (94%), particularly the pleura, pericardium, peritoneum, chest

37、wall, and retroperitoneum. Metastatic lesions may maintain their high water content at imaging evaluation.,.,38,These foci are often nodular, with nonspecific features of solid but nonmyxoid elements. On CT, the attenuation of the round cell areas is similar to muscle, and on MR intermediate signal

38、intensity on T1 WI and T2WI. Identification of foci with this appearance in the background of a myxoid liposarcoma should alert the radiologist to biopsy these regions, to aid in appropriately aggressive preoperative treatment.,The identification of round cell component in the myxoid Liposarcoma on

39、MRI,.,39,Myxoid liposarcoma with prominent round cell component in the calf of a 40-year-old man with a slowly enlarging mass.,.,40,2.“Cyst mimicker “:(5 to 22% of cases) Without an adipose component on MRI; Unique features for differential diagnosis: The intramuscular location of lower extremities

40、,which is characteristic for myxoid liposarcoma (ganglion, synovial cyst); Lack of surrounding edema and thick walls ,as well as absence of correlative appropriate clinical history (liquefied hematoma or abscess); CEMRI: either diffuse or nodular enhancement-solid not cystic,Imaging features of Myxo

41、id Liposarcoma,.,41,Myxoid liposarcoma simulating a cyst in a 48-year-old woman MR images show a relatively well-defined homogeneous intermuscular mass (arrows) with low to intermediate signal intensity on T1 WI and homogeneous high-signal intensity on T2WI. No fat is apparent. Although characteristics simulate a cyst, the location is markedly atypical, requiring further imaging to exude a myxoid tumor masquerading as a cyst (cyst mimicker) . The coronal T1WI fat suppressed MR