18F-FDG PET/CT显像在胃癌诊断中的应用

[目的]评价18F-FDG PET/CT显像在胃癌诊断中的应用.[方法]49例经胃镜和病理确诊的胃癌患者进行18F-FDG PET/CT显像,其诊断结果与病理学检查、其他影像学检查及临床随访比较.[结果] 49例患者18F-FDG PET/CT阳性44例,阳性率89.8％;39例有淋巴结转移患者中18F-FDGPET/CT显像发现32例,灵敏度为82.1％(32/39); 12例有远处转移患者中18F-FDG PET/CT显像发现11例,灵敏度91.6％(11/12).[结论]18F-FDG PET/CT显像对胃癌原发灶、淋巴结转移和远处转移具有较高的灵敏度,18F-FDG PET/CT显像在胃癌诊断中具有较高的临床价值.     

18F-FDG PET/CT显像在食管癌分期中的应用

目的:探讨18F-FDG PET/CT显像在食管癌分期中的应用价值.方法:对23例病理学确诊的食管癌患者,术前1周行全身PET/CT显像,根据病理结果评价PET/CT显像在食管癌分期中的应用价值.结果:19例患者进行了食管癌切除和淋巴结清除术,PET/CT显像发现50处病灶,与病理结果相比较,假阳性5处,假阴性3处,PET/CT诊断灵敏性为94%,特异性为76%;另4例患者因PET/CT发现多发转移而改变了治疗方案.结论:应用18F-FDG PET/CT进行食管癌检查能显著提高分期的敏感性和准确性,具有较好的临床应用前景.     

FDG PET/CT与PET对食管癌淋巴结转移的诊断价值比较

目的比较脱氧葡萄糖(FDG)PET/CT和PET对食管癌淋巴结转移的诊断价值。方法随机选择拟行手术治疗的食管癌患者35例,行PET/CT检查。全部患者均行食管癌切除和淋巴结清扫术,以术后病理检查为金标准,比较PET/CT与PET对食管癌淋巴结转移的诊断价值。结果术后病理结果显示,25例患者存在淋巴结转移。共切取淋巴结313组,其中65组为转移淋巴结。PET确定转移真阳性淋巴结53组,真阴性淋巴结217组。PET/CT确定转移真阳性淋巴结61组,真阴性淋巴结229组。PET诊断转移假阴性淋巴结12组,其中8组被PET/CT校正,包括1组颈深淋巴结,4组食管旁淋巴结,1组胃左动脉干淋巴结,1组左贲门旁淋巴结,1组胃小弯淋巴结;PET诊断转移假阳性淋巴结31组,其中12组被PET/CT校正,3组缘于食管癌原发灶不均匀摄取,2组缘于颈部组织生理性摄取,7组缘于胃肠道生理性摄取或良性病变。PET的敏感性、特异性和准确性分别为81.54%、87.50%和86.26%,PET/CT的敏感性、特异性和准确性分别为93.85%、91.24%和92.65%,PET/CT诊断食管癌淋巴结转移的敏感性和准确性均高于PET(P<0.05)。结论与PET相比,FDG PET/CT诊断食管癌淋巴结转移具有更高的敏感性和准确性,可提供更多有价值的诊断信息。     

18F-FDG PET融合CT对胸中段食管鳞癌区域淋巴结分期的前瞻性研究

目的 探讨正电子发射型电子计算机断层(PET)显像在胸中段食管鳞癌患者术前区域淋巴结临床分期中的应用价值.方法 30例行现代二野淋巴结清扫术的胸中段食管鳞癌患者,术前进行全身18F-氟代脱氧葡萄糖(18F-FDG)PET融合CT显像与CT显像,对区域淋巴结检查结果进行对照研究.结果 现代二野淋巴结清扫术后发现24例患者区域淋巴结阳性(80.00%),转移区域淋巴结总数为61枚.18F-FDG PET融合CT发现食管区域淋巴结转移16例,敏感性、特异性和Youden指数分别为66.67%、100.0%和0.67.CT检出8例.61枚转移区域淋巴结中18F-FDG PET融合CT定性43枚(70.49%),定量分析发现转移区域淋巴结计算标准化摄取值(SUV)为2.9±1.2,均＞2.5;CT检出区域淋巴结转移数24枚(39.34%).18F-FDG PET融合CT在区域淋巴结转移患者与区域淋巴结转移数均明显优于CT,P＜0.05.结论 18F-FDG PET融合CT在诊断胸中段食管鳞癌区域淋巴结转移方面可能优于CT.     

^18F-FDG PET/CT显像在食管癌分期中的应用

目的：探讨^18F-FDG PET/CT显像在食管癌分期中的应用价值。方法：对23例病理学确诊的食管癌患者,术前1周行全身PET/CT显像,根据病理结果评价PET/CT显像在食管癌分期中的应用价值。结果：19例患者进行了食管癌切除和淋巴结清除术,PET/CT显像发现50处病灶,与病理结果相比较,假阳性5处,假阴性3处,PET/CT诊断灵敏性为94%,特异性为76%;另4例患者因PET/CT发现多发转移而改变了治疗方案。结论：应用^18F-FDG PET/CT进行食管癌检查能显著提高分期的敏感性和准确性,具有较好的临床应用前景。     

~(18)F-FDG PET/CT诊断乳腺癌及腋窝淋巴结转移的价值

目的探讨~(18)F-脱氧葡萄糖(~(18)F-FDG)正电子发射断层扫描(PET/CT)诊断乳腺癌和腋窝淋巴结(ALN)转移的价值。方法选取2015年7月至2016年4月间海南省人民医院收治的79例拟诊断为乳腺癌的患者,均采用~(18)F-FDG PET/CT、超声检查和钼靶X线检查。比较三种不同方式的诊断结果,对比分析~(18)F-FDG PET/CT检查结果和术后病理结果,讨论~(18)F-FDG PET/CT诊断乳腺癌和ALN转移的价值。结果术后病理结果显示,所有疑为乳腺癌的患者均确诊为乳腺癌。~(18)F-FDG PET/CT检查结果为阳性64例,阴性15例,灵敏度为81.0%;超声检查结果为阳性47例,阴性32例,灵敏度为59.5%;钼靶X线检查结果为阳性53例,阴性26例,灵敏度为67.1%,~(18)F-FDG PET/CT检查灵敏度明显高于超声检查和钼靶X线,差异均有统计学意义(P<0.05)。~(18)F-FDG PET/CT诊断ALN转移的灵敏度为35.0%,准确度为70.9%,特异度为83.1%,阴性预测值为79.0%,阳性预测值为41.2%。结论~(18)F-FDG PET/CT对乳腺癌的诊断的灵敏度明显优于超声检查和钼靶X线检查,诊断ALN转移有较好的特异度和准确度。     

18F-FDG PET/CT对原发性乳腺癌诊断和淋巴结分期的临床价值

目的评价18F-脱氧葡萄糖(18F-FDG)PET/CT对原发性乳腺癌诊断和淋巴结分期的临床价值。方法临床拟诊为乳腺癌的27例女性患者,手术前分别行乳腺钼靶X线和18F-FDG PET/CT检查。全部患者均行手术治疗,共切除32个病灶。23例患者接受了腋淋巴结廓清术,并行病理学诊断。结果32个病灶中,25个为乳腺癌病灶,7个为良性病变。18F-FDG PET/CT诊断的敏感度为80.0%,特异度为71.4%。T1期病灶8个,PET/CT诊断阳性6个;T2期病灶14个,PET/CT诊断阳性12个;T3期病灶2个,PET/CT均诊断阳性。对区域淋巴结转移,PET/CT诊断的敏感度为60.0%,特异度为84.6%,诊断准确度为73.9%。结论对于怀疑多中心乳癌、病期较晚、需要全面评价区域淋巴结状态或疑有远处转移的患者,PET/CT具有优势,对乳腺癌的分期有重要帮助,但尚不适宜于作为乳腺癌的常规检查。     

18F-FDGPET/CT全身显像对乳腺癌复发和转移诊断价值分析

目的:探讨18F-FDG PET/CT全身显像对治疗后乳腺癌复发和转移的诊断价值。方法:回顾性分析山东省肿瘤医院2004-12-01-2009-12-31行18F-FDG PET/CT显像检查的乳腺癌患者142例,统计18F-FDG PET/CT显像诊断的灵敏度、特异性和准确性,并与增强CT及全身骨扫描进行对比。结果:18F-FDG PET/CT和增强CT对乳腺癌复发和转移的灵敏度分别为85.5%(71/83)和77.1%(64/83),特异性分别为88.1%(52/59)和84.7%(50/59),准确性分别为86.6%(123/142)和80.3%(114/142)。18F-FDG PET/CT诊断淋巴结转移的阳性率为89.5%(34/38),高于增强CT的73.7%(28/38),P=0.031;对于局部复发、肺转移、肝转移和脑转移的诊断,18F-FDG PET/CT和增强CT差异无统计学意义;对于骨转移的诊断,18F-FDG PET/CT的灵敏度为70.0%,全身骨扫描为90.0%,两者的特异性分别为100.0%和58.3%。结论:18F-FDG PET/CT显像对治疗后乳腺癌复发和转移诊断具有较高的灵敏度和特异性,但对于不同部位转移灶的诊断应合理选择检查方法。     

^18F—FDGPET／CT显像与CT增强在肾癌诊断中的对比研究

目的:评价18F-脱氧葡萄糖(18F-fluorodeoxyglucose,18F-FDG)PET/CT显像对肾癌诊断和治疗方案选择的临床应用.方法:回顾性分析50例临床诊断为肾癌患者的全身18F-FDG PET/CT及CT平扫加增强的影像学资料,比较两者对肾癌的诊断价值.结果:50例中,经手术病理证实为肾癌的有41例,其余9例因18F-FDG PET/CT显像发现远处转移放弃手术.18F- FDG PET/CT检查敏感度80%;CT平扫加增强敏感度92%.9例转移病例中4例为腹膜后淋巴结转移,2例两肺多发转移,2例伴有下腔静脉和肾静脉癌栓形成,1例骨转移合并肝转移,而CT平扫加增强仅发现1例肾静脉和下腔静脉癌栓形成.结论:18F-FDG PET/CT对诊断原发性肾癌的敏感性不如CT,但对淋巴结转移及远处转移的诊断优于CT,对肾癌的分期及治疗方案的选择有重要意义.     

~(18)F-FDG SPECT/PET代谢显像对肺癌的诊断价值

[目的]探讨18F-FDG符合线路SPECT/PET代谢显像在肺癌诊断中的价值。[方法]经临床诊断为肺癌的60例患者进行18F-FDG代谢显像。SPECT/PET图像重建用迭代法(OS-EM)获得三维图像。18F-FDGSPECT/PET图像分析采用T/NT比值法及5点打分法对病灶作出定性分析,计算诊断灵敏度并与CT比较。[结果]60例肺癌患者中,18F-FDG显像阳性55例,灵敏度91.67%;CT阳性54例,灵敏度90%。SPECT/PET提示23例双侧肺门、纵隔、锁骨上及腹主动脉旁淋巴结转移,共发现78个转移的淋巴结;CT提示16例,共发现25个转移的淋巴结。在27例经病理学检查确诊为非小细胞肺癌的患者中,18F-FDGSPECT/PET显像对其纵隔淋巴结转移的灵敏度为85.71%,特异性为83.33%。[结论]18F-FDG符合线路SPECT/PET代谢显像对肺部肿瘤及其转移灶的诊断具有较高的灵敏度,对局部有淋巴结转移的肿瘤较CT检查具有较高的特异性,并可对肿瘤的良、恶性作出定性分析,值得临床推广应用。     

18F-FDG PET/CT在鼻咽癌诊断及分期中的临床价值

背景与目的:PET/CT能够通过准确显示肿瘤形态、大小及相邻关系从而对鼻咽癌(NPC)进行诊断及分期研究.本研究结合PET/CT、MRI结果及部分颈部小淋巴结病理结果,探讨18SF-FDG PET/CT在鼻咽癌TNM分期中的价值.方法:从2005年9月至2007年3月.选取行PET/CT和MRI检查的鼻咽癌患者68例.PET数据采用2D采集模式,CT扫描电压140 kV,采用自动毫安量跟踪扫描加血管增强的扫描方案,18F-FDG按3.7～5.5 MBq/kg剂量静脉注射.MRI检查采用T1W和T2W成像及T1W增强扫描成像.并对其中10例患者颈部小淋巴结切除和穿刺组织病理检查,进行图像与病理对照.结果:68例鼻咽癌患者所有鼻咽区域的病灶PET/CT均可以清晰显示,MRI和PET/CT显示病灶一致:对于直径≤1 cm的138枚PET/CT示阳性小淋巴结,MRI仅有约28%可作不肯定提示.10例鼻咽癌患者颈部16枚PET/CT显示阳性小淋巴结与病理结果相符14枚,符合率达87.5%.对于颈部肿大淋巴结PET/CT.和MRI均能显示,对部分放疗过程PET/CT示增殖活性明显受抑制的肿大淋巴结,MRI和PET/CT增强扫描可见强化.对于其中8例Ⅳb期鼻咽癌患者肺、骨、肝脏等转移灶,PET/CT全身扫描可清晰显示病灶,而MRI具有较多限制.由于18F-FDG PET/CT检查使其中24例的分期进行调整.结论:18F-FDG-PET/CT扫描采用自动毫安量跟踪扫描加血管增强的扫描方案,充分利用PET/CT信息进行鼻咽癌的临床分期,其结果较MRI全面、可靠.     

18F-FDG PET-CT确定非小细胞肺癌淋巴结放疗靶区的初步探讨

目的探讨18F-FDG PET-CT确定非小细胞肺癌(NSCLC)患者区域淋巴结放疗靶区的价值。方法回顾性分析58例经根治性手术治疗的NSCLC患者,术前同期行PET-CT和CT检查。经盲法阅片后,由肿瘤放射治疗医师结合影像诊断结果分别在PET-CT和CT图像上勾画靶区,并与病理诊断结果进行对照。结果CT诊断纵隔淋巴结转移的灵敏度、特异度、准确率、阳性预测值及阴性预测值分别为56.0%、54.2%、54.8%、38.9%和70.3%,PET-CT分别为88.0%、85.4%、86.3%、75.9%和93.2%,两者差异均有统计学意义(P<0.05)。CT和PET-CT对诊断肺门区域淋巴结的差异无统计学意义。18F-FDG PET参与靶区勾画后,46.5%的患者淋巴结靶区改变,其靶区完全包含转移性淋巴结的准确率为75.9%,与单纯CT(48.3%)的准确率比较,差异有统计学意义(P<0.05)。结论18F-FDG PET-CT能更准确地估计NSCLC患者区域淋巴结转移的范围,从而指导放疗靶区的勾画。     

Potential impact of 18F-FDG PET/CT on patients selection for neoadjuvant chemotherapy before radical cystectomy

BackgroundThe detection of lymph node metastases in bladder cancer has a major impact on treatment decisions and patients prognosis. Due to limited value of conventional imaging, the place of molecular and functional imaging needs to be precised, particularly in the neoadjuvant setting.MethodsFrom June 2011 to June 2013, 102 patients with clinically localized BCa were simultaneously staged with ¹⁸F-FDG PET/CT before RC. This study assessed the diagnostic accuracy of ¹⁸F-FDG PET/CT for the detection of metastases in normal-sized lymph nodes using extended pelvic lymph node dissection and histopathology as the reference standard.ResultsA total of 1211 LNs were examined histopathologically. Sixty-seven (5.5%) metastatic nodes were found in 26/102 patients (25.5%). Lymph node density was 22%. On patient-based analysis, sensitivity, specificity, predictive positive value (PPV), negative positive value (NPV) and accuracy for ¹⁸F-FDG PET/CT were calculated as 50%, 96.2%, 80%, 86.2% and 85.3% respectively. On a field-based analysis, sensitivity, specificity, PPV, NPV and accuracy for ¹⁸F-FDG PET/CT were calculated as 50.0%, 99.0%, 71.9%, 97.4%, and 96.5% respectively. The majority of missed metastases were micrometastasis <5 mm in long axis diameter.Conclusions¹⁸F-FDG PET/CT improves diagnostic efficacy for lymph node staging in patients staged N0 with conventional cross-sectional imaging. ¹⁸F-FDG PET/CT could be used as a surrogate marker for detection of metastases in non-enlarged pelvic lymph nodes and enhances management strategy guiding patients selection for neoadjuvant chemotherapy.     

18F-FDG PET-CT CT 在诊断乳腺癌腋窝淋巴结转移状态的对比研究*

目的:通过与CT对比,探讨18F-FDG PET-CT 在诊断乳腺癌患者腋窝淋巴结转移中的价值。方法:回顾性分析22例行乳腺癌改良根治术患者的术前18F-FDG PET-CT 、CT图像。在CT图像上分别以淋巴结最短径>0.5cm（A 标准）、最短径≥1.0cm（B 标准）及最长径≥1.0cm（C 标准）为判定淋巴结转移的标准;在PET-CT 图像上,分别以目测腋窝淋巴结出现18F-FDG 异常放射性浓聚为判定淋巴结阳性的标准（D 标准）及半定量分析法异常放射性浓聚灶最大标准化摄取值（maximum standard uptake value ,SUV max）≥1.0 为判定淋巴结转移标准（E 标准）。 以术后病理为金标准,比较不同影像方法诊断腋窝淋巴结转移状态的价值。结果:乳腺癌患者腋窝阳性与阴性淋巴结在大小及SUV max 方面的差异均具有统计学意义。不同诊断标准中,以PET-CT 的总体诊断准确率及与病理吻合度Kappa 值最高,其中A 标准灵敏度最高（59.3%）而特异度最低（83.5%）;B 标准特异度和阳性预测值最高（分别为98.2% 、72.7%）,而灵敏度和阴性预测值最低（27.1% 、88.4%）;C 标准各项诊断指标相对较差,无突出项;PET-CT 图像目测与半定量诊断结果相同,其诊断准确性（90.1%）、阴性预测值（92.5%）均优于单独CT诊断,且与病理诊断吻合度较好（Kappa 值为0.57）,在诊断灵敏度（55.9%）、特异度（96.1%）及阳性预测值（71.7%）方面与单独CT比较也具较高诊断价值,阳性组SUV max 较阴性组明显为高,二者差异有统计学意义（P=0.000）。 不同影像方法在诊断腋窝淋巴结转移时差异有统计学意义（P<0.05）。 结论:18F-FDG PET-CT 是一种直观有效的评价乳腺癌腋窝淋巴结转移状态的方法。      

误诊为周围型肺癌的肺结核18F-FDG PET-CT表现

目的分析误诊为周围型肺癌的肺结核18F-FDG PET-CT表现,提高对肺结核PET-CT表现的认识。方法回顾性分析31例在我院行18F-FDG PET-CT检查并误诊为周围型肺癌的肺结核的PET-CT表现。27例行双时像显像。所有患者均行胸部屏气螺旋CT扫描。所有病例通过组织学或诊断性治疗证实。结果 31例肺结核(均径≤4.0cm)均为周围型肺结节,23例有分叶,27例有毛刺,27例有胸膜牵拉,13例有小卫星灶。肺结核病灶的SUVmax常规为3.87±3.20,SUVmax延迟为4.10±2.94,△SUVmax为0.97±1.02,RI为28.92%±32.11%。肺结核病灶的SUVmax与其均径呈正相关(r=0.816,P<0.01),且在不同大小病变组中的分布差异有统计学意义(P<0.05)。5例患者有肺门和/或纵隔淋巴结肿大,最大淋巴结的平均短径为(1.52±0.41)cm,肿大淋巴结的SUVmax明显高于非肿大淋巴结(P<0.01)。15例患者的淋巴结为高密度,淋巴结的SUVmax在高密度淋巴结组与非高密度淋巴结组的差异没有统计学意义(P>0.05)。结论误诊为周围型肺癌的肺结核病灶,形态学表现和摄取程度可与周围型肺癌相似,但较少伴有淋巴结肿大,当病灶中央出现摄取分布稀疏区以及病灶周围有小卫星灶时,对诊断有帮助。     

Maximum standardized uptake value on PET/CT in preoperative assessment of lymph node metastasis from thoracic esophageal squamous cell carcinoma

The presence of lymph node metastasis is an important prognostic factor for patients with esophageal cancer. Accurate assessment of lymph nodes in thoracic esophageal carcinoma is essential for selecting appropriate treatment and forecasting disease progression. Positron emission tomography combined with computed tomography （PET/CT） is becoming an important tool in the workup of esophageal carcinoma. Here, we evaluated the effectiveness of the maximum standardized uptake value （SUVmax） in assessing lymph node metastasis in esophageal squamous cell carcinoma （ESCC） prior to surgery. Fifty-nine surgical patients with pathologically confirmed thoracic ESCC were retrospectively studied. These patients underwent radical esophagectomy with pathologic evaluation of lymph nodes. They all had 18F-FDG PET/CT scans in their preoperative staging procedures. None had a prior history of cancer. The pathologic status and PET/CT SUVmax of lymph nodes were collected to calculate the receiver operating characteristic （ROC） curve and to determine the best cutoff value of the PET/CT SUVmax to distinguish benign from malignant lymph nodes. Lymph node data from 27 others were used for the validation. A total of 323 lymph nodes including 39 metastatic lymph nodes were evaluated in the training cohort, and 117 lymph nodes including 32 metastatic lymph nodes were evaluated in the validation cohort. The cutoff point of the SUVmax for lymph nodes was 4.1, as calculated by ROC curve （sensitivity, 80%; specificity, 92%; accuracy, 90%）. When this cutoff value was applied to the validation cohort, a sensitivity, a specificity, and an accuracy of 81%, 88%, and 86%, respectively, were obtained. These results suggest that the SUVmax of lymph nodes predicts malignancy. Indeed, when an SUVmax of 4.1 was used instead of 2.5, FDG-PET/ CT was more accurate in assessing nodal metastasis.     

依据CT及MRI确定区域淋巴结转移的病理对照研究

目的 评估分别依据CT及DWMRI确定胸部肿瘤区域淋巴结转移的诊断效能,寻找更为合理准确的淋巴结勾画方法及界值。方法 2012—2013年共入组43例胸部肿瘤患者(食管癌35例、NSCLC 8例),术前1周完善胸腹强化CT及DWMRI检查,分别依据CT及DWIMR图像确定转移的区域淋巴结,以术后病理为金标准统计并比较两种方法的诊断效能。两种图像结果行χ²检验。结果 CT图像与DWI诊断区域淋巴结转移的敏感性、特异性、准确性、阳性预测值、阴性预测值、约登指数分别为57.1%、96.3%、93.8%、50.0%、97.2%、53.4%和60.0%、98.9%、96.5%、77.8%、97.4%、58.9%,DWMRI诊断的特异性、准确性、阳性预测值优于CT (P=0.005、0.038、0.022)。依据CT诊断的40个淋巴结中20个为假阳性,其中15个(75%)可经DWMRI信息纠正。CT诊断假阴性淋巴结15个,其中3个(20%)可经DWMRI得以分辩。全组35个癌性淋巴结中5个影像学未见明确肿大,余30个中有13个短径<1.0 cm (43.3%)。结论 依据CT判断区域淋巴结转移局限性明显,单以短径≥1.0 cm作为靶区勾画标准可能会漏照较多癌性淋巴结。DWMRI诊断区域淋巴结转移的特异性、准确性及阳性预测值优于CT,可有效排除非癌性肿大淋巴结并分辨部分小的转移性淋巴结。     

The role of F-FDG PET/CT for evaluation of metastatic mediastinal lymph nodes in patients with lung squamous-cell carcinoma or adenocarcinoma

Objectives

To evaluate the efficacy of ¹⁸F-FDG PET/CT in depicting metastatic mediastinal lymph nodes in patients with lung squamous-cell carcinoma (LSCC) or lung adenocarcinoma (LAC) in a tuberculosis-endemic country.

Methods

This study retrospectively reviewed patients with LSCC or LAC, who underwent preoperative ¹⁸F-FDG PET/CT to assess mediastinal lymph node metastasis. Patients with the short-axis of mediastinal lymph node ≤ 15 mm were included. PET/CT interpretation was analyzed in two ways. Firstly, with CT for anatomical localization, lymph nodes showing greater ¹⁸F-FDG uptake than vessel pool on PET were regarded malignant. Secondly, lymph nodes with positive uptake on PET were considered malignant, only when nodes had neither calcification nor higher attenuation than vessel pool on CT.

Results

One hundred and sixteen LSCCs and 234 LACs were evaluated. With CT for anatomical localization, the sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of PET were 78.6%, 45.5%, 53.4%, 31.4% and 87.0% in LSCC group, and 61.8%, 66.3%, 65.0%, 42.9% and 80.9% in LAC group. PET showed higher specificity and accuracy in LAC group compared with LSCC group (p = 0.001 and p = 0.038, respectively). Considering calcification or high attenuation on CT, the sensitivity, specificity, accuracy, PPV and NPV of PET/CT were 71.4%, 67.0%, 68.1%, 40.8% and 88.1% in LSCC group, and 54.4%, 86.1%, 76.9%, 61.7% and 82.2% in LAC group. Compared with PET, PET/CT possessed higher specificity and accuracy in LSCC group (p = 0.000 and p = 0.000, respectively), and higher specificity, accuracy and PPV in LAC group (p = 0.000, p = 0.000 and p = 0.022, respectively).

Conclusions

¹⁸F-FDG PET displays limited efficacy in assessing mediastinal lymph node metastasis with the short-axis diameter <15 mm in LSCC and LAC groups and higher false-positivity in LSCC group. The specificity and accuracy in LSCC and LAC groups are enhanced by interpreting attenuation characteristic on CT.     

双源CT双能量扫描融合三维重建技术在诊断胃癌及淋巴结中应用的研究

目的 本研究探讨双源CT双能量增强扫描获得的参数能否区分胃癌病灶与正常胃壁,以确定病变范围,提高早期胃癌符合诊断率,精准N分期。方法 通过西门子Somatom Definition Flash双源CT对术前胃癌患者进行双能量增强扫描,将采集的数据经Syngo.Via软件分析及三维重建,获得胃癌病灶、正常胃壁、转移淋巴结与非转移淋巴结的绝对碘值、标准化碘值及虚拟单能量能谱曲线的斜率并记录,结合术后病理结果,应用统计学方法分析判断两两之间的差异。结果 胃癌病灶的绝对碘值为(3.329±0.812)g/L,标准化碘值为(64.006±17.450)%,虚拟单能量能谱曲线的斜率为(-2.916±1.3227),与正常胃壁的绝对碘值(1.563±0.708)g/L,标准化碘值(37.122±16.267)%,虚拟单能量能谱曲线的斜率(-1.621±1.4028)比较,均存在统计学差异(P＜0.05);转移淋巴结的绝对碘值为(2.968±0.547)g/L,标准化碘值为(63.597±14.633)%,虚拟单能量能谱曲线的斜率为(-2.532±0.753),与非转移淋巴结绝对碘值(1.465±0.408)g/L,标准化碘值(35.240±14.357)%,虚拟单能量能谱曲线的斜率(-1.378±0.726)比较,均存在统计学差异(P＜0.05)。结论 双源CT双能量扫描获得的参数结合三维重建技术有助于确定病变范围,提高早期胃癌的符合诊断率,区分转移淋巴结与非转移淋巴结以提高N分期的准确率。