【作者】 宁秋萍；

【导师】 高硕；

【作者基本信息】 天津医科大学 ， 影像医学与核医学， 2011， 硕士

【摘要】 目的腹水是临床常见病症之一,其良恶性鉴别对于指导临床制定治疗方案和判断预后有重要价值,但也是临床较难解决的问题。目前细胞学以及常规影像学对于腹水性质的判断有一定价值,但尚不能完全解决该临床难题,而18F-FDG PET/CT可以通过全面了解患者体部的情况,判断腹水的病因。本文1.探讨18F-FDG PET/CT显像对于鉴别腹水良恶性并对恶性腹水原发灶进行定位的临床应用价值；2.探讨18F-FDG PET/CT显像对于导致恶性腹水的肿瘤分期特别是腹腔转移方面的诊断价值。资料和方法回顾性分析2007年1月至2009年6月共50例腹水患者18F-FDG PET/CT体部显像资料。PET/CT检查标准如下：①肿瘤标志物升高；②形态学发生改变；③经腹水实验室检查、传统影像检查仍无法明确病因。PET图像经衰减校正、迭代重建得到断层图像,与CT断层图像融合后进行多方位显示。由2位有经验的核医学专业医师采用目测法和半定量分析法结合CT结果联合判读,并与病理或随访结果进行对比。测量腹膜病变最大标准摄取值(SUVmax)及腹膜病变最大厚度Tmax(cm),良恶性组腹膜SUVmax以及Tmax间差异的比较采用t检验。分别计算PET/CT及单纯CT诊断腹水原发灶以及腹腔转移灶中的灵敏度、特异度、准确度、阳性预测值和阴性预测值,并进行卡方检验。PET显像阳性组及阴性组间生存期的比较采用Wilcoxon检验。数据资料使用SPSS17.0统计软件包进行处理,P<0.05为差异有统计学意义。结果①经病理证实恶性病变导致腹水31例,包括原发腹膜癌9例、卵巢癌7例、胰腺癌4例、胃癌3例、肝癌2例、肝癌合并肺癌1例、肺癌1例、胆囊癌1例、结肠癌1例、卵巢癌合并腹膜癌1例、krukenberg瘤1例,其中18F-FDG PET/CT正确诊断27例；经临床及随访证实良性病变导致腹水19例,包括结核性腹膜炎4例、不明原因4例(经腹水脱落细胞学检查及临床随访仍未明确原发灶),肝源性腹水3例、心源性腹水2例、肾源性腹水2例、自身免疫性2例、低蛋白血症1例、慢性腹膜炎1例,其中18F-FDG PET/CT正确诊断16例。3例假阴性包括2例腹膜癌及1例结肠癌腹腔转移；2例假阳性包括1例肾功能不全、1例结核性腹膜炎；另2例诊断为恶性病变但原发灶不明确患者,其中1例病理证实为卵巢癌合并腹膜癌,1例病理证实为腹膜癌,总的诊断准确度为90.0%。此外,经病理证实PET/CT还发现15例淋巴结转移、2例骨转移、1例肺内转移、1例胸膜转移。淋巴结转移按数量多少依次为卵巢癌、胰腺癌、肝癌、胃癌；淋巴结转移灶灶中12例为腹腔及盆腔淋巴结,另3例分别为内乳区、双肺门及纵隔淋巴结；1例胃癌及1例胆囊癌发生骨转移灶,转移灶位于肋骨干及椎体；1例胆囊癌发生肺内转移,1例胃癌发生胸膜转移。②良性病变组腹膜病灶平均Tmax为1.09±0.96cm,平均SUVmax为3.44±3.59；恶性组平均Tmax为3.07±2.04cm,平均SUVmax为6.89±3.63。良、恶性组腹膜病变之间平均SUVmax及平均Tmax差异具有统计学意义(t=--3.300,P=0.002；t=--4.605,P=0.000)：③经Wilcoxon检验,PET显像阳性者和阴性者生存期之间差异有统计学意义(Z=-15.848,P=0.000双侧)。平均SUVmax>3.0与<3.0患者生存时间有统计学差异(t=-3.573,P=0.001)；平均Tmax是否>3.Ocm(t=-1.620,P=0.116)患者年龄是否>60岁(t=-0.561,P=0.577)、患者性别差异(t=--0.146,P=0.884)对生存时间无明显影响,差异无统计学意义。良、恶性组腹水患者生存期无明显统计学意义(P>0.05)。结论首先,18F-FDG PET/CT显像对于判断腹水病因,寻找恶性腹水原发灶有重要临床应用价值。结合其结果可明确病灶的大小、范围,可初步定位、定性,从而指导临床治疗方案的制定。其次,在腹水病因不明确的情况下,由于它能全面显示肿瘤的分布状况,尤其是腹腔转移灶以及腹膜转移灶的检出,据此也可间接鉴别腹水的良、恶性。再次,18F-FDG PET/CT显像也存在一定缺陷：亦存在假阴性与假阳性,其中结核性腹膜炎最易出现假阳性,所以应当密切结合临床综合资料和其他检查以减少误诊。更多还原

【Abstract】 Objective:Ascites is one of the most comman diseases,its differential diagnosis of benign and malignant is a key role to establish treatment strategies and prognosis.At present,Cytology and clinical conventional imaging skills have certain value,but can not solve this difficult problem in clinic. But 18F-FDG PET/CT imaging has shown a larger advantage in knowing the whole body physical condition,and found the primary to ascites, indirectly responsible for the property of ascites. So the aim of this study was to evaluate the diagnostic value of 18F-FDG PET/CT for the patients with ascites of unknown causes.Materials and Methods:Fifty patients with ascites of unknown causes refered to our department for whole-body 18F-FDG PET/CT were retrospectively reviewed.The causes of their ascites could not be confirmed by laboratory examinations and clinical conventional imaging skills.Data of PET scan were reconstructed and fused with CT slices.PET,CT and fusion images were displayed in three orthogonal projections. Images were interpreted on the Xeleris workstation and all of the PET images were reviewed visually and semi-quantitatively. PET images were reviewed in conjunction with relevant the CT and the fused images used to identify malignant and benign lesions.The maximum standard uptake value (SUVmax) and the maximum diameter (Tmax) of peritoneum were measured,their differences of SUVmax and Tmax between benign lesions diseases and malignant diseases were also compared.SPSS17.0 statistical package was used to analyze in this study. P<0.05 was considered statistically significant.Results:①27 out of 31 patients with ascites caused by malignant diseases were correctly diagnosed.31 patients including 9 peritoneal cancer,7 ovarian cancer,2 hepatocelluar carcinoma,1 hepatic carcinoma with lung cancer,1 lung cancer,3 gastric cancer,4 pancreatic cancer,1 gallbladder carcinoma,1 colon cancer,and 1 ovarian cancer combined peritoneal cancer, and 1 Krukenberg tumor;16 out of 19 patients with benign diseases were correctly diagnosed.The causes of these 19 ascites patients consist of 3 liver disease,2 cardiac disease,2 kidney disease,1 hypoproteinemia,4 tuberculous peritonitis,2 autoimmune diseases,1 chronic peritonitis,4 ascites of unknown origin.3 false negative cases were 1 colon cancer with abdominal metastases,2 peritoneal cancer;2 false positive cases were 1 renal insufficiency and 1 tubereculous peritonitis;2 cases were regarded as malignant but failed in finding primary by PET/CT,one is ovarian cancer combined peritoneal cancer,another is peritoneal cancer.The accuracy of 18F-FDG PET/CT were 90.0%.PET/CT found 15 lymph node metastasis,2 bone metastasis,1 lung metastasis,1 pleural metastasis besides Peritoneal metastases.12 of lymph nodes metastases were abdomen and pelvic nodes,the rest of lymph nodes located in internal mammary (1), bilateral hilar (1), mediastinal(1). Pathological specimens were obtained from all these lymph nodes.②Tmax and SUVmax in benign ascites patients were 1.09±0.96cm,3.44±3.59 respectively;and 3.07±2.04cm,6.89±3.63 in malignant ascites patients.A bigger SUVmax (t=-3.300,P=0.002;) and Tmax (t=-4.605,P=0.000) was observed in malignant ascites patients.③According to Wilcoxon signed rank test,the survival difference of positive result and negative result was significant (Z=-15.848,P=0.000 bilateral),a longer survival was observed in those patients whose SUVmax smaller than 3.0(t=-3.573,P=0.001).SUVmax>3.0 or<3.0 (t=-3.513,P=0.001),Tmax>3.0cm or <3.0cm (t=-1.620,P=0.116),age>60 year or<60 year (t=-0.561,P=0.577), male or female(t=-0.146,P=0.884) did not show statistically signigicance.Conclusions:Firstly,18F-FDG PET/CT has useful clinical diagnostic value in finding primary of ascites.It can depict size,region,and make a primary level diagnosis of ascites property to instruct physician making treatment protocols.Secondly,because PET/CT can give the whole body condition of tumor distribution,in some unknown primary cases,the metastases in abdomain and in pelvic or Peritoneal metastases were contribute to diagnosis. It was helpful to differential diagnosis.Thirdly,18F-FDG PET/CT also has something not all were desired, false positive and false negative can not avoid,one of the most reason of false positive is tuberculous peritonitis which should be pay more attention to reduce the false positive cases.更多还原