High-resolution fluorodeoxyglucose positron emission tomography with compression ("positron emission mammography") is highly accurate in depicting primary breast cancer

We sought to prospectively assess the diagnostic performance of a high-resolution positron emission tomography (PET) scanner using mild breast compression (positron emission mammography [PEM]). Data were collected on concomitant medical conditions to assess potential confounding factors. At four centers, 94 consecutive women with known breast cancer or suspicious breast lesions received 18F-fluorodeoxyglucose (FDG) intravenously, followed by PEM scans. Readers were provided clinical histories and x-ray mammograms (when available). After excluding inevaluable cases and two cases of lymphoma, PEM readings were correlated with histopathology for 92 lesions in 77 women: 77 index lesions (42 malignant), 3 ipsilateral lesions (3 malignant), and 12 contralateral lesions (3 malignant). Of 48 cancers, 16 (33%) were clinically evident; 11 (23%) were ductal carcinoma in situ (DCIS), and 37 (77%) were invasive (30 ductal, 4 lobular, and 3 mixed; median size 21 mm). PEM depicted 10 of 11 (91%) DCIS and 33 of 37 (89%) invasive cancers. PEM was positive in 1 of 2 T1a tumors, 4 of 6 T1b tumors, 7 of 7 T1c tumors, and 4 of 4 cases where tumor size was not available (e.g., no surgical follow-up). PEM sensitivity for detecting cancer was 90%, specificity 86%, positive predictive value (PPV) 88%, negative predictive value (NPV) 88%, accuracy 88%, and area under the receiver-operating characteristic curve (Az) 0.918. In three patients, cancer foci were identified only on PEM, significantly changing patient management. Excluding eight diabetic subjects and eight subjects whose lesions were characterized as clearly benign with conventional imaging, PEM sensitivity was 91%, specificity 93%, PPV 95%, NPV 88%, accuracy 92%, and Az 0.949 when interpreted with mammographic and clinical findings. FDG PEM has high diagnostic accuracy for breast lesions, including DCIS.     

Necessity of a uniform start for scanning after FDG injection in brain PET study

The authors' goal was to show the importance of starting scanning at a uniform time after F-18 fluorodeoxyglucose injection in positron emission tomography (PET) brain study. METHOD: Fifteen healthy normal subjects underwent FDG-PET to obtain glucose metabolic images starting 60 min and 70 min after FDG injection, respectively. The two sets of images were compared in a voxel-by-voxel analysis. RESULTS: In the bilateral posterior cingulate gyrus, parietal and frontal association cortices, the FDG uptakes were larger on the 70 min scan images than on the 60 min scan images; the 60 min scans resembled Alzheimer's metabolic reduction area. Similarly the FDG uptakes were larger in the pons and vermis on the 60 min scan image than on the 70 min scan image. CONCLUSIONS: Regional FDG uptake is different depending on the time scanning starts after FDG injection, even with a 10 minute difference in start time and different scanning time may lead to misdiagnosis. It is important to standardize the start time of FDG PET after FDG injection in brain PET.     

Sarcomatoid renal cell carcinoma: Rapid dissemination detected on FDG PET‐CT

We present the FDG PET‐CT findings in a patient with persistent pain 7 weeks after a nephrectomy and lymph node dissection for a sarcomatoid renal cell carcinoma. Although conventional imaging was unable to detect evidence of metastatic spread outside the para‐aortic nodes, a PET‐CT scan showed unexpected extensive dissemination. Currently, there are no reports in the literature of the PET‐CT findings in sarcomatoid renal cell carcinomas.     

18F-FDG PET/CT观察原发性睾丸弥漫大B细胞淋巴瘤

目的 观察原发性睾丸弥漫大B细胞淋巴瘤（PT-DLBCL）的¹⁸F-FDG PET/CT表现及其诊断价值。方法 回顾性分析5例经病理确诊的PT-DLBCL患者的术前及化学治疗前¹⁸F-FDG PET/CT资料,观察其原发灶、淋巴结及结外病灶表现,并分析¹⁸F-FDG PET/CT的诊断价值。结果 5例PT-DLBCL中,¹⁸F-FDG PET/CT示3例双侧睾丸病变、2例右侧睾丸病变;其原发灶最大标准摄取值（SUV_max）为13.90~26.80,中位SUV_max为16.00。5例中,4例伴淋巴结内病变,见于腹膜后4例、盆腔3例、腹股沟及颈部各1例,其SUV_max 4.40~24.70,中位SUV_max为14.40;3例伴睾丸外结外病变,累及右侧臀部皮下组织、右上腹部皮肤及口咽各1例,病灶SUV_max分别为4.30、5.20及40.90。5例患者均接受全身化学治疗,1例完全缓解（CR）,3例部分缓解（PR）,1例疾病进展（PD）。结论 ¹⁸F-FDG PET/CT可见PT-DLBCL病灶摄取增高,对于诊断其睾丸原发灶、淋巴结病变及结外病变均具一定价值。     

组合扫描方案改善18F-FDG PET/CT工作效率

目的 观察组合扫描方案对改善¹⁸F-FDG PET/CT工作效率的价值。方法 前瞻性纳入75例需接受PET/CT检查患者,随机分为A、B及C组各25例,分别采用不同¹⁸F-FDG注射剂量和采集时间行PET/CT检查,观察A、B和C方案及3种组合方案对¹⁸F-FDG PET/CT工作效率的影响。结果 A、B、C 3组每公斤体质量放射性计数、肝脏平均标准摄取值（SUV_mean）及纵隔SUV_mean差异均无统计学意义（P均>0.05）。模拟结果显示,显像剂总剂量为1 850、3 700及5 550 MBq时,采用组合方案可缩短总检查时间;总剂量达7 400 MBq及以上时,采用组合方案可使单位时间内检查数量增加1~2例并缩短总检查时间;总剂量相同情况下,采用组合方案,显像剂例均成本低于单一方案。结论 采用不同¹⁸F-FDG注射剂量和PET床位采集时间组合方案有助于增加检查例数、缩短总检查时间,提高PET/CT工作效率;必要时分批运输显像剂可进一步降低例均成本。     

18F-FDG PET/CT影像组学判断乳腺癌人表皮生长因子受体2表达状态

目的 观察¹⁸F-FDG PET/CT影像组学判断乳腺癌人表皮生长因子受体2（HER2）表达状态的价值。方法 纳入100例乳腺癌患者,包括HER2（+）组28例、HER2（-）组72例,比较组间PET/CT参数,包括病灶最大标准摄取值（SUV_max）及其标准差（SD）、平均标准摄取值（SUV_mean）及肿瘤代谢体积的差异。于标准化后的PET图像中手动分割病灶ROI,获取其影像组学特征,根据降维后的影像组学特征及其系数的线性加权获得病灶影像组学风险评分（RRS）;针对差异有统计学意义的指标绘制受试者工作特征曲线,计算曲线下面积（AUC）,评价其判断乳腺癌患者HER2状态的效能。采用Bootstrap 1000重复抽样进行内部验证,计算校正AUC,并以DeLong检验比较。以决策曲线分析评价患者净获益情况。结果 HER2（+）组病灶SUV_max、SUV_mean及SD均大于HER2（-）组（P均<0.05）。共获取704个影像组学特征,经筛选最终获得10个非零系数的特征用于计算RRS,HER2（+）组RRS大于HER2（-）组（P<0.001）。以RRS判断乳腺癌患者HER2状态的AUC大于病灶SUV_max、SUV_mean及SD （P均<0.05）,其诊断敏感度为78.57%、特异度为77.78%。决策曲线分析结果表明,RRS可在较大概率阈值范围内带给患者更多净获益。结论 ¹⁸F-FDG PET/CT影像组学用于判断乳腺癌HER2状态具有一定价值。     

急性B淋巴母细胞白血病/B淋巴母细胞性淋巴瘤合并肾脏浸润18F-FDG PET/CT表现

前体淋巴细胞恶性肿瘤以T细胞来源为主,而B淋巴母细胞性淋巴瘤(B-lymphoblastic lymphoma,B-LBL)仅占约10%,常累及皮肤或骨骼,纵隔受累少见。B-LBL与B淋巴母细胞白血病(B-acute lymphoblastic leukemia,B-ALL)可归为一类,骨髓中淋巴母细胞比例≥25%时为B-ALL,比例在5%~25%时应诊断为B-LBL骨髓浸润[1]。肾脏淋巴瘤少见,且多为继发性。本研究观察B-LBL/ALL肾脏浸润的18 F-FDG PET/CT表现。     

18F-FDG PET/CT联合血清神经元特异性烯醇化酶及胃泌素释放肽前体诊断小细胞肺癌

目的评价¹⁸F-FDG PET/CT显像联合血清神经元特异性烯醇化酶(NSE)及胃泌素释放肽前体(Pro-GRP)对小细胞肺癌(SCLC)的诊断价值。方法回顾性分析80例接受¹⁸F-FDG PET/CT、血清NSE及Pro-GRP检测的肺占位患者,根据病理及随访结果分为SCLC组(n=40)和良性病变组(n=40);计算¹⁸F-FDG PET/CT联合肿瘤标志物诊断SCLC的敏感度、特异度、准确率、阳性预测值及阴性预测值,绘制受试者工作特征(ROC)曲线,评价不同指标诊断SCLC的效能。结果¹⁸F-FDG PET/CT联合肿瘤标志物诊断SCLC的敏感度、特异度、准确率、阳性预测值及阴性预测值分别是95.00%、100%、97.50%、100%及95.24%。NSE、Pro-GRP、Pro-GRP+NSE以及三项联合诊断SCLC的曲线下面积(AUC)分别为0.86、0.88、0.96和0.98。结论¹⁸F-FDG PET/CT显像联合血清NSE+PRo-GRP检测可提高诊断SCLC的敏感度和特异度,对早期诊断、分期及治疗具有指导意义。     

18F-AlF-NOTA-octreotide联合18F-FDG PET/CT显像用于神经内分泌瘤

目的 观察¹⁸F-AlF-NOTA-octreotide（¹⁸F-OCT）联合¹⁸F-FDG PET/CT显像用于神经内分泌瘤（NET）的临床价值。方法 回顾性分析21例同期接受¹⁸F-OCT和¹⁸F-FDG PET/CT显像并经病理学证实的NET患者,其中7例已接受原发瘤根治性切除术、2例原发灶不明;根据2010年WHO分级标准,将12例明确存在原发瘤者分为中/低级别组9例和高级别组3例,对比原发瘤及转移灶在2种显像中的阳性比例、摄取水平及治疗后影像学变化。结果 原发瘤大小与¹⁸F-FDG最大标准摄取值（SUV_max）显著相关（r=0.731,P<0.05）,但与¹⁸F-OCT无明显相关（r=0.311,P>0.05）。中/低级别组9例原发瘤中,8例¹⁸F-OCT显像阳性,SUV_max中位数为33.80（6.10,56.55）;7例¹⁸F-FDG显像阳性,SUV_max中位数3.80（1.40,8.80）（Z=-2.345,P<0.05）。高级别组3例原发瘤中,¹⁸F-FDG检出3例,¹⁸F-OCT 2例。¹⁸F-OCT联合¹⁸F-FDG PET/CT显像检测转移灶阳性比例高于单一。追踪观察1例胰腺NET术后肝脏多发转移患者,奥曲肽对其¹⁸F-OCT显像阳性病灶取得良好疗效。结论 ¹⁸F-OCT联合¹⁸F-FDG PET/CT显像可作为检测NET的辅助手段,并有望用于预估疗效。