特殊示踪剂正电子发射体层显像在肺部病变诊断中的应用

目的 探讨胆碱、甲硫氨酸、脱氧胸腺嘧啶核苷、乙酸盐为示踪剂的正电子发射体层显像(PET)在肺部病变诊断中的应用价值.方法 2002年6月至2007年6月对100例肺部占位病变的患者行PET检查.其中~(11)C-胆碱(CH)-PET检查58例,~(11)C-甲硫氨酸(MET)-PET检查16例,~(18)F-脱氧胸腺嘧啶核苷(FLT)-PET检查22例,~(11)C-乙酸盐(AC)-PET检查4例.结果 采用目测法判读,半定量分析法测量病变标准摄取值,结果与病理诊断及随访结果对照.结果CH-PET定性诊断灵敏度、特异度、符合率分别为84.2%(32/38)、57.9%(11/19)、75.4%(43/57).MET-PET定性诊断灵敏度、特异度、符合率分别为6/7、6/9、75.0%(12/16).FLT-PET检查定性诊断灵敏度、特异度、符合率分别为85.7%(12/14)、2/8、63.6%(14/22).CH.PET、MET-PET及FLT-PET中肿瘤标准摄取值与肿瘤大小、患者年龄不相关.AC.PET检查仅1例透明细胞癌肺转移显影,2例鳞状细胞癌、1例腺癌没有显影.结论 这些示踪剂PET对肺部病变的定性诊断有帮助,但存在假阳性和假阴性结果.     

~(18)FDG-PET在肺癌诊断中的价值

目的　研究氟脱氯葡萄糖F18 正电子发射计算机电子扫描 (1 8FDG PET)在鉴别肺部肿块性质和肺癌术前纵隔淋巴结转移分期中的应用价值。　方法　对 34例肺部肿块患者进行1 8FDG PET和CT检查 ,PET资料分别采用目测法和计算标准化摄取值 (SUV)的半定量法进行分析 ,并同病理结果对照。　结果　目测法1 8FDG PET诊断肺部肿块性质的敏感度、准确度分别是 93%、85 % ;CT分别为 6 3%、5 3% ,2种方法差异有显著性意义 (P <0 0 5 ) ;半定量法准确度为 74% ,与CT相比 ,差异也有显著性意义 (P <0 0 5 )。肺部恶性肿块的SUV是 4 4± 1 9,良性为 2 2± 1 7,2者差异有显著性意义 (P <0 0 5 )。1 8FDG PET和CT 2种检查方法术前对纵隔淋巴结转移的分期与病理结果符合率分别为10 0 %和 78% ,2者差异有显著性意义 (P <0 0 5 )。　结论　同CT相比 ,1 8FDG PET能更准确地鉴别肺部肿块性质及确定纵隔淋巴结转移分期 ,是一种较好的无创性肺癌诊断技术。     

Usefulness of positron emission tomography for assessing the response of neoadjuvant chemoradiotherapy in patients with esophageal cancer

BACKGROUND: In this study, we retrospectively assessed the performance of 18-F-fluorodeoxyglucose positron emission tomography (FDG-PET) compared with computed tomography (CT) and esophagography for assessing the response of advanced esophageal squamous cell carcinoma (SCC) to neoadjuvant chemoradiotherapy. METHODS: We studied 10 patients with thoracic esophageal SCC who received neoadjuvant chemoradiotherapy followed by surgery. Tumor response was assessed by CT, endoscopy, esophagography and FDG-PET before and after neoadjuvant treatment. RESULTS: Assessment of the rate of decrease in standardized uptake value (SUV) revealed a partial response (more than 50% decrease) in 5 (50%) of the patients, and assessment of length decrease of FDG uptake showed a partial response in 9 (90%) of the patients. Comparison of the histological response and the rate of decrease of various parameters revealed significant associations between histological response and tumor length (P <0.05), SUV after neoadjuvant therapy (P <0.05), and reduction in the extent of FDG uptake (P <0.01). However histological response was not significantly correlated with the rate of reduction of SUV, for both CT and esophagography. CONCLUSIONS: FDG-PET may be of considerable value for predicting the pathologic response of esophageal SCC to neoadjuvant therapy. Despite assessment of SUV before neoadjuvant therapy, low FDG uptake after therapy and reduction in the extent of FDG uptake may provide a reliable assessment of the response to therapy.     

18F-FDG PET在胰腺癌患者预后评估中的价值

目的 评估18F-FDG PET判断胰腺癌患者预后的价值.方法 回顾性分析54例胰腺癌病例资料.取所有病例PET检查的标准摄取值(standard uptake value,SUV)平均值4为截断点分组,A组22例(SUV≤4),B组32例(SUV＞4),分析两组患者的预后.结果 A组1、3年生存率为68.18%、34.91%;B组1、3年生存率为33.61%、11.95%,两组生存率比较差异有统计学意义(P=0.01);Cox回归分析提示肿瘤分期和SUV是胰腺癌患者预后的独立危险因素.结论 18F-FDG PET在判断胰腺癌预后方面有一定的价值.     

Surgical target selection in cerebral glioma surgery: linking methionine (MET) PET image fusion and neuronavigation.

OBJECTIVE: The objective of this study was to investigate the histological correlate of (11)C-methionine (MET) PET uptake of brain gliomas by image fusion for navigated surgery. METHODS: Twenty-seven patients (18 male, 9 female; mean age 42 years; range 11-77 years; 8 low-grade and 11 high-grade astrocytomas or mixed gliomas, 8 oligodendrogliomas) underwent MET PET studies preoperatively. RESULTS: MET PET tumor uptake was detected in 26 of 27 patients (96.3%). The quantitative MET tumor standardized uptake value (SUV) ratio was significantly higher in malignant gliomas and oligodendrogliomas than in low-grade gliomas (2.76/2.62 vs. 1.67, p=0.03). Generally, qualitative visual grading of MET uptake revealed 2 main patterns: focal MET uptake in 12 and uniform global MET uptake in 11 patients. Focal uptake corresponded to malignant glioma histology in 66.7%, and uniform global uptake to oligodendroglial histology in 72.7%. In oligodendrogliomas, global MET uptake constituted 81.5% (range 53.8-135%) of the MRI T(1) tumor volume on average and was limited to the MRI FLAIR tumor volume in 86% (7/8) of patients. Tissue samples of focal MET uptake areas correlated with histological anaplasia in 66.6% (8/12 glioma patients), although 62.5% (5/8 patients) lacked MRI contrast enhancement. CONCLUSION: MET PET image fusion may facilitate the targeting of anaplastic foci in homogeneous MRI non-enhancing gliomas for biopsy, may identify oligodendroglial histology preoperatively as well as characterize biologically active tumor volumes within MRI T(1)/FLAIR tumor areas of candidate patients for resection.     

Clinical usefulness of 18-fluorodeoxyglucose positron emission tomography in the management of patients with nonpancreatic periampullary neoplasms

BACKGROUND: 18-Fluorodeoxyglucose positron emission tomography (18-FDG PET) has been investigated for the diagnosis and staging of gastrointestinal malignancies including pancreatic adenocarcinoma. The aim of this study was to examine the clinical usefulness of 18-FDG PET in the diagnosis and follow-up evaluation of patients with periampullary neoplasms. METHODS: Twenty-five patients underwent whole-body 18-FDG PET and abdominal computed tomography (CT). Pathologic confirmation was obtained in all patients by surgical resection or biopsy examination. The 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value (SUV). Positivity was assumed when a focal uptake occurred with an SUV of 2.5 or greater. RESULTS: Between January 1998 and December 2003, 14 ampullary, 7 bile duct, and 4 duodenal tumors were included in the study. PET showed increased focal uptake in 22 patients (88%): 11 of 14 (79%) ampullary tumors, and 100% of bile duct and duodenal tumors. PET showed a focal uptake in 11 of 12 patients without detectable mass at CT scan, and lymph node metastases in 6 patients. An SUV value of 2.7 discriminated adenomas or noninvasive cancers (n = 6) from invasive malignancies (n = 14). Follow-up evaluation including CT scan and PET was performed in 12 patients: PET showed recurrent disease not seen by CT in 4 patients, confirmed CT findings in 6 patients, and showed an unsuspected primary lung cancer in 1 patient and colon cancer in another patient. CONCLUSIONS: 18-FDG PET is very sensitive for detecting periampullary neoplasms. It may be useful to differentiate benign or borderline lesions from invasive tumors when no mass has been identified by traditional imaging. Finally, it is very useful in the follow-up evaluation of resected patients to identify recurrent disease or other malignancies.     

Positron-emission tomography as a prognostic tool for early-stage lung cancer

BACKGROUND: Positron-emission tomography (PET) shows tissue metabolic activity in the form of the standard uptake value (SUV). This study examines the prognostic value of the SUV for early-stage lung cancer. METHODS: A retrospective review of 187 patients undergoing PET for potential lung cancer. Data collected included patient demographics, tumor pathology, and survival information. Data were correlated with PET results to determine if a prognostic relationship exists. RESULTS: The sensitivity and specificity of PET for detecting malignant lesions were 98% and 24%. Malignant lesions had a higher SUV than benign lesions (5.9 +/- 6.2 versus 2.2 +/- 1.8, P < .0001). The average SUV of well-differentiated tumors was 2.6 +/- 3.1 versus 5.9 +/- 5.5 for other tumors (P = .010). There was a strong correlation between tumor stage and SUV (analysis of variance, P < .0001). There was no difference in tumor SUV for survivors versus nonsurvivors. CONCLUSIONS: The SUV correlates with prognostic indicators, such as tumor stage and grade. The SUV alone was not an independent predictor of survival.     

Standardized uptake values for breast carcinomas assessed by fluorodeoxyglucose-positron emission tomography correlate with prognostic factors

Several studies have revealed the diagnostic value of fluorodeoxyglucose-positron emission tomography for breast carcinomas. However, breast carcinomas display considerable variation in 18F-labeled 2-fluoro-2-deoxy-D-glucose uptake, and few papers have reported the clinical utility of the standardized uptake values (SUV). The purpose of this study is to investigate the relationship between SUV assessed by positron emission tomography (PET) and the clinicopathological characteristics of breast carcinoma. We reviewed 52 breast carcinomas of 45 patients presented at our department between January 2004 and July 2005. We compared the histopathological findings of the breast carcinomas with the preoperative SUV. Of the 52 breast carcinomas, 49 (94%) were detected by preoperative PET. A positive correlation was found between the SUV and tumor size (P < 0.01), histological grade (P < 0.01), the expression of the estrogen receptor (P < 0.001), progesterone receptor (P < 0.01), and p53 (P < 0.01). The number of metastatic axillary lymph nodes (r = 0.73; P < 0.0001) and the MIB-1 labeling rates (r = 0.5; P < 0.01) correlated with the SUV of the breast carcinomal. No relationship existed between the SUV and the following: histological tumor types (P = 0.07), human epidermal growth factor receptor-2 status (P = 0.10), and the presence of metastatic lymph nodes (P = 0.10). The SUV of the breast carcinomas correlate with several histopathological and immunohistochemical prognostic factors. We can obtain information on the degree of malignancy of the carcinoma and prognostic factors by preoperative PET examination.     

肺鳞癌中葡萄糖易化扩散转运蛋白-1过度表达与18 氟脱氧葡萄糖摄取的关系

目的　了解葡萄糖易化扩散转运蛋白 1(Glut1)在肺鳞癌组织中过度表达与肿瘤对18氟脱氧葡萄糖 (FDG)摄取之间的关系。　方法　 1999年 4月～ 2 0 0 1年 3月对 2 3例肺鳞癌患者行全身正电子发射体层显像 (PET)检查 ,测定肿瘤对FDG的最大与平均标准摄取值 (SUVmax与SUVmean)及健侧正常肺组织的标准摄取值 (SUVlung)。所有肿瘤均手术切除。应用标准链霉菌抗生物素蛋白 过氧化物酶亲和 (SP)免疫组织化学方法 ,对肿瘤及正常支气管肺组织的Glut1表达情况进行检测 ,以染色阳性细胞率与染色强度 (染色强度 1～ 5 )表示。　结果　 2 3例肺癌组织均有Glut1过度表达 [阳性细胞率 (6 9± 18) % ,染色强度 4 6± 0 7],正常支气管肺组织无Glut1过度表达。肿瘤FDG摄取高于相应的正常肺组织 ,SUVmax、SUVmean与SUVlung分别为 8 33± 4 14、6 10± 3 0 0与 0 38± 0 13(P <0 0 1)。Glut1过度表达程度、FDG摄取、肿瘤大小之间呈正相关性 (P <0 0 1)。结论　肺鳞癌组织中的Glut1过度表达与其FDG摄取有直接的关系。     

18F-FLTPET/CT在肿瘤诊断中的应用

在PET及PET／CT的应用中,人们逐渐发现仅使用18F-氟脱氧葡萄糖（18F-FDG）作为示踪剂是远远不够的。细胞增殖显像剂18F-氟脱氧胸苷（18F-FLT）是一种新型的示踪剂,本文就18F—FLT在肿瘤诊断、分期及疗效评价方面进行综述。     

Visualization of prostate cancer with 11C-choline positron emission tomography

BACKGROUND AND OBJECTIVE: Visualization of prostate cancer with positron emission tomography (PET) using 2-[18F]-2-deoxy-D-glucose (FDG) as radiopharmaceutical is limited by the low uptake of FDG in the tumor and by radioactivity excreted into the bladder. More specific PET radiopharmaceuticals would be welcome. Carbon-11 labeled choline (CHOL) is a new radiopharmaceutical potentially useful for tumor imaging as it is incorporated in the cell membranes as phosphatidylcholine. We prospectively studied the visualization of prostate cancer using CHOL PET. METHODS: A total of 25 consecutive patients with histologically proven prostate cancer and five patients with a benign prostate were included. PET images were performed with an ECAT HR(+) using 400MBq CHOL. Data acquisition was started at 5 minutes post-injection. Attenuation-corrected images were evaluated visually. Standardized uptake values (SUV) were calculated of the normal prostate gland and of the prostate tumor tissue. RESULTS: The normal prostate was visualized with a mean SUV of 2.3 (range 1.3-3.2). The primary tumor could be visualized with a mean SUV of 5.0 (range 2.4-9.5). Lymph node metastases >5mm could be identified. Non-specific uptake of CHOL was noticed in the intestines. Little to no radioactivity in the bladder was observed. CONCLUSION: Carbon-11-choline is avidly taken up in prostate cancer, both primary tumor and lymph node metastases, in the virtual absence of urinary radioactivity. These results confirm the early results obtained by others and permit further clinical research on the value of CHOL PET as a metabolic imaging technique in areas where conventional imaging have a limited sensitivity.     

三种类型肺癌18氟脱氧葡萄糖摄取量的初步研究

目的探讨肺鳞癌、腺癌、细支气管肺泡癌对18氟脱氧葡萄糖(fluorine -18 fluorode～oxyglucose,FDG)摄取的差异以及影响肺癌摄取FDG的常见因素. 方法对82例肺癌患者行全身或肺部正电子发射体层显像(positron emission tomography,PET)检查,测定肿瘤组织FDG的标准摄取值(standard uptake value,SUV)、最大与平均标准摄取值(SUVmax、SUVmean)、正常肺组织的SUV(SUVlung). 结果 82例患者中,肿瘤组织对FDG的摄取能力均高于相应的正常肺组织(P＜0.01).肺鳞癌、腺癌、细支气管肺泡癌的SUVmax分别为8.42±4.05,5.91±3.91和 2.97±1.10;SUVmean 分别为6.12±2.90,4.35±3.10和 2.25±0.99,三者差异有显著性意义(P＜0.01).SUV与肿瘤的大小呈正相关(P＜0.01).血糖水平与正常肺组织的SUV对肿瘤的SUV有影响(P＜0.05).结论 (1)肺癌组织对FDG的摄取能力高于正常肺组织,而且不同组织类型的肺癌之间SUV值差异有显著性意义.(2)肿瘤的大小与FDG摄取量存在着正相关性.(3)临床上解释肺癌患者PET检查结果时应考虑到血糖等因素的影响.     

Preoperative FDG-PET for axillary metastases in patients with breast cancer

HYPOTHESIS: Fludeoxyglucose F 18 (FDG) positron emission tomography (PET) can be used to predict axillary node metastases. DESIGN: Case series. SETTING: Comprehensive breast care center. PATIENTS: Fifty-one women with 54 biopsy-proven invasive breast cancers. INTERVENTION: Whole-body FDG-PET performed before axillary surgery and interpreted blindly. MAIN OUTCOME MEASURES: Axillary FDG activity, quantified by standardized uptake value (SUV); axillary metastases, quantified histologically; and tumor characteristics. RESULTS: There was PET activity in 32 axillae (59%). The SUVs ranged from 0.7 to 11.0. Twenty tumors had an SUV of 2.3 or greater, and 34 had an SUV of less than 2.3. There were no significant differences between these 2 groups except in axillary metastasis size (SUV /=2.3): mean age, 53 vs 58 years (P = .90); mean modified Bloom-Richardson score, 7.7 vs 7.6 (P = .20); lymphovascular invasion present, 25% vs 36% (P = .40); mean Ki-67 level, 25% vs 32% (P = .20); mean tumor size, 2.9 vs 3.2 cm (P = .05); and axillary metastasis size, 0.9 vs 1.7 (P = .001). By adopting an SUV threshold of 2.3, FDG-PET had a sensitivity of 60%, a specificity of 100%, and a positive predictive value of 100%. CONCLUSIONS: Patients with an SUV greater than 2.3 had axillary metastases. This finding obviates the need for sentinel lymph node biopsy or needle biopsy to diagnose axillary involvement. Surgeons can proceed to axillary node dissection to assess the number of nodes involved, eliminate axillary disease, or perhaps provide a survival benefit if preoperative FDG-PET has an SUV greater than 2.3.     

18F-FDG PET/CT成像观察西妥昔单抗对结直肠癌裸鼠移植肿瘤影响的实验研究

目的建立结直肠癌裸鼠移植肿瘤模型,用小动物¹⁸F-FDG PET/CT技术评价西妥昔单抗对人结直肠癌移植肿瘤的影响。 方法BALB/c裸鼠皮下分别接种人结直肠癌细胞HCT116、LIM1215,建立HCT116与LIM1215两种荷瘤裸鼠模型。将成瘤后的模型分为对照组和西妥昔单抗治疗组(n=5),并且全程观察肿瘤体积变化情况。给药1周后采用小动物¹⁸F-FDG PET/CT技术评价实体肿瘤模型,并测量各组织与器官的¹⁸F-FDG最大每克组织摄取率。 结果小动物¹⁸F-FDG PET/CT成像显示裸鼠接种部位肿瘤内放射性摄取值增高,LIM1215与HCT116肿瘤模型的治疗组与对照组相比,肿瘤/组织或器官¹⁸F-FDG摄取比率均普遍降低,其中肿瘤/颈肌、肿瘤/心脏与肿瘤/肝脏比值差异有统计学意义(P=0.047、0.008、0.024),但两种肿瘤模型的肿瘤体积测量结果均显示,治疗组与对照组的肿瘤生长趋势差异无统计学意义。 结论在西妥昔单抗对结直肠癌裸鼠移植肿瘤模型的治疗实验中,西妥昔单抗对肿瘤生长尚未有明显抑制作用时,小动物¹⁸F-FDG PET/CT可监测到肿瘤葡萄糖代谢的变化。     

肺腺癌葡萄糖易化扩散转运蛋白-1过度表达与18氟脱氧葡萄糖摄取的关系

目的　探讨葡萄糖易化扩散转运蛋白 1(Glut1)在肺腺癌组织中的表达与肿瘤对18氟脱氧葡萄糖 (FDG)摄取之间的关系。方法　对 1999年 4月至 2 0 0 1年 3月收治的 2 4例肺腺癌患者行正电子发射体层显像 (PET)检查 ,测定肿瘤最大与平均标准摄取值 (SUVmax与SUVmean)及正常肺组织的标准摄取值 (SUVlung)。应用标准链霉菌抗生物素蛋白—过氧化物酶亲和 (SP)免疫组织化学方法对手术切除的肿瘤及正常支气管肺组织的Glut1表达情况进行检测 ,以染色阳性细胞率与染色强度 ( 1～ 5 )表示。结果　 2 4例肺癌组织均有Glut1过度表达 [阳性细胞率 35 %± 2 3% ,染色强度 3 7± 0 9],正常支气管肺组织无Glut1过度表达。肿瘤SUVmax、SUVmean( 5 4 6± 3 32、4 0 5± 2 5 4 )明显高于SUVlung( 0 4 3± 0 15 ,Z分别为 - 2 92 9、- 3 4 6 5 ,P均 <0 0 1)。Glut1过度表达程度、FDG摄取、肿瘤大小之间呈正相关 (P <0 0 1)。结论　肺腺癌组织有Glut1过度表达 ,并与FDG摄取相关。     

Prognostic significance of preoperative [18-F] fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging in patients with resectable soft tissue sarcomas

OBJECTIVE: The objective of this study was to evaluate the prognostic significance of preoperative positron emission tomography (PET) using 2-fluoro-2-deoxy-D-glucose (FDG) by calculating the mean standardized uptake values (SUV) in patients with resectable soft tissue sarcomas (STS). SUMMARY AND BACKGROUND DATA: FDG-PET might be used as an adjunctive tool (in addition to biopsy and radiologic tomography) in the preoperative prognostic assessment of resectable STS. METHODS: A total of 74 adult patients with STS underwent preoperative FDG-PET imaging with calculation of the SUV. Clinicopathologic data and the SUV were analyzed for an association with the clinical outcome. The first and the third quartiles of the SUV distribution function were used as cutoff values (1.59 and 3.6). Survival was estimated by the Kaplan-Meier method. Univariate and multivariate analyses were performed using log-rank test and the Cox proportional hazards regression model. RESULTS: In 55 cases, STS were completely resected (follow up 40 months): 5-year recurrence-free survival rates in patients with SUV <1.59, 1.59 to <3.6, and > or =3.6 were 66%, 24%, and 11%, respectively (P = 0.0034). SUV was a predictor for overall survival (5-year rates: 84% [SUV <1.59], 45% [SUV 1.59 to <3.6], and 38% [SUV > or =3.6]; P = 0.057) and local tumor control (5-year rates: 93% [SUV <1.59], 43% [SUV 1.59 to <3.6], and 15% [SUV > or =3.6]; P = 0.0017). By multivariate analysis, SUV was found to be predictive for recurrence-free survival. The prognostic differences with respect to the SUV were associated with tumor grade (P = 0.002). CONCLUSION: The semiquantitative FDG uptake, as measured by the mean SUV on preoperative PET images in patients with resectable STS, is a useful prognostic parameter. SUV with cutoff values at the first and the third quartiles of the SUV distribution predicted overall survival, recurrence-free survival, and local tumor control. Therefore, FDG-PET can be used to improve the preoperative prognostic assessment in patients with resectable STS.     

^18FDG—PET在肺癌诊断中的价值

目的研究氟脱氯葡萄糖F18-正电子发射计算机电子扫描(18FDG-PET)在鉴别肺部肿块性质和肺癌术前纵隔淋巴结转移分期中的应用价值.方法对34例肺部肿块患者进行18FDG-PET和CT检查,PET资料分别采用目测法和计算标准化摄取值(SUV)的半定量法进行分析,并同病理结果对照.结果目测法18FDG-PET诊断肺部肿块性质的敏感度、准确度分别是93%、85%;CT分别为63%、53%,2种方法差异有显著性意义(P＜0.05);半定量法准确度为74%,与CT相比,差异也有显著性意义(P＜0.05).肺部恶性肿块的SUV是4.4±1.9,良性为2.2±1.7,2者差异有显著性意义(P＜0.05).18FDG-PET和CT2种检查方法术前对纵隔淋巴结转移的分期与病理结果符合率分别为100%和78%,2者差异有显著性意义(P＜0.05).结论同CT相比,18FDG-PET能更准确地鉴别肺部肿块性质及确定纵隔淋巴结转移分期,是一种较好的无创性肺癌诊断技术.     

(18)F]Fluorodeoxyglucose positron emission tomography and its prognostic value in lung cancer.

OBJECTIVE: Positron emission tomography (PET) is being increasingly used as an accurate and non-invasive modality in diagnosis, staging and post-therapy assessment in patients with lung cancer. In this study, we examine whether the uptake of [(18)F]fluorodeoxyglucose (FDG), a marker of increased glucose metabolism in neoplastic cells, is of prognostic value in patients with primary lung cancer. METHODS: We have retrospectively analyzed 77 patients (mean age, 63. 0 years; male/female ratio, 53:24) with primary lung cancers who underwent whole body and localized thoracic PET as part of their diagnostic and staging procedures prior to consideration of surgical resection. The standardized uptake value (SUV) of injected FDG for each primary lesion was correlated with tumour histology and the patient's clinical outcome. RESULTS: A SUV of 20 or greater was found to be of significant prognostic value. The chance of survival (with 95% confidence intervals (CI)) at 12 months post-surgery for the various SUV groups was as follows: 75.2% (59.6-85.5) for SUV<10; 67.5% (29.0-88.2) for SUV 10-<12; 63.6% (29.7-84.5) for SUV 12-<15; 66.7% (19.5-90.4) for SUV 15-<20; 16.7% (0.01-0.52) for SUV>20. A SUV of 20 or more is associated with a 4.66 times increase in hazard, compared with lower levels of SUV. We found no significant correlation between tumour histology and SUV. CONCLUSION: We have previously reported on the significant advantages of PET in the staging and surgical care of patients with lung cancer. The present study adds further support for an additional prognostic role for PET in the management of thoracic malignancy as determined by the amount of labelled-FDG taken up by the primary lesion.     

Molecular Imaging of Proliferation and Glucose Utilization: Utility for Monitoring Response and Prognosis after Neoadjuvant Therapy in Locally Advanced Gastric Cancer

Background

Metabolic imaging of gastric cancer is limited due to the 30% of primary tumors that are not ¹⁸F-fluorodeoxyglucose (FDG) avid. In contrast, the proliferation marker ¹⁸F-fluorothymidine (FLT) has been shown to visualize also non-FDG-avid gastric tumors. In this study we tested whether FLT-positron emission tomography (PET) can improve the predictive potential of molecular imaging for assessing response to neoadjuvant therapy in gastric cancer compared with FDG-PET.

Methods

45 patients with gastric cancer underwent FDG- and FLT-PET before and 2 weeks after initiation of chemotherapy. FDG/FLT-PET findings and Ki67 immunohistochemistry were correlated with clinical and histopathological response and survival.

Results

14 patients had non-FDG-avid tumors, whereas all tumors could be visualized by FLT-PET. No significant association of clinical or histopathological response with any of the analyzed metabolic parameters [initial standardized uptake value (SUV), SUV after 2 weeks, change of SUV for FDG/FLT] was found. Univariate Cox regression analysis for Ki67 and metabolic parameters revealed significant prognostic impact for survival only for FLT SUV_mean day 14 (p = 0.048) and Ki67 (p = 0.006). Multivariate Cox regression analysis (including clinical response, Lauren type, ypN category, and FLT SUV_mean day 14) revealed Lauren type and FLT SUV_mean day 14 as the only significant prognostic factors (p = 0.006, p = 0.002).

Conclusions

FLT uptake 2 weeks after initiation of therapy was shown to be the only imaging parameter with significant prognostic impact. Neither FLT-PET nor FDG-PET were correlated with histopathological or clinical response. However, these data must be interpreted with caution due to the single-center trial study design, relatively short follow-up, poor response rates, and unfavorable prognosis.     

Preoperative Positron Emission Tomography with Fluorine-18-Fluorodeoxyglucose is Predictive of Prognosis in Patients with Hepatocellular Carcinoma after Resection

Background: Hepatocellular carcinomas (HCCs) accumulate fluorine-18 fluorodeoxyglucose (FDG) to various degrees. The standardized uptake values (SUVs) of FDG-positron emission tomography (PET) in high-grade HCCs are significantly higher than those in low-grade HCCs. Aim: The aim of this study was to evaluate the possible usefulness of FDG-PET in predicting the prognosis of HCC patients after resection. We analyzed the relationship between the tumor to non-tumor SUV ratios (SUV ratio) and surgical outcome in 31 patients. Results: Of the 31 cases of HCC studied, seven (23%) exhibited SUV ratios greater than 2, as the cutoff value. The percentage of patients with poorly differentiated HCC was greater in the higher SUV ratio group (SUV ratio >2) than in the lower SUV ratio group (SUV ratio <2) (57 vs. 32%). The overall survival was significantly longer in the lower SUV ratio group than in the higher SUV ratio group (5-year-survival rate: 63 vs. 29% P = 0.006) (median survival time: 2310 vs.182 days). Conclusion: The SUV ratio was related significantly to disease-related death as well as other predictive factors, including the number of tumors, the size, stage, and involvement of vessels, and the involvement of the capsule. Consequently, we conclude that the SUV ratio provides information of prognostic relevance in patients with HCC before surgery.