Deep-inspiration breath-hold PET/CT of lung cancer: maximum standardized uptake value analysis of 108 patients

Our aim was to compare the maximum standardized uptake value (SUVmax) between breath-hold (BH) PET/CT and free-breathing (FB) PET/CT. METHODS: The features of phantom data were analyzed, after which a clinical study was performed. A total of 108 consecutive patients with lung cancer were examined using lutetium oxyorthosilicate (LSO)-based PET/CT. The patients were instructed to breathe freely during FB PET/CT. In BH PET/CT, the patients were instructed to hold their breath in the maximal inspiration position during the scout scan, for 10 s of the CT scan, and for as long as possible during the PET scan. BH time was recorded using a respiratory monitoring device. The %BH-index was defined as the percentage difference between SUVmax of FB PET and that of BH PET. Statistical analyses were performed using the following factors: %BH-index, age, body mass index, 18F-FDG dosage, blood glucose, BH time, lesion size, and location. RESULTS: The highest %BH-index was 223.2. %BH-index in the lower lung area was significantly higher than that in the upper lung area (51.8 +/- 49.5 vs. 16.9 +/- 25.6, respectively). Lesion volume and maximum diameter in the high-%BH-index group were significantly lower than those in the low-%BH-index group, with the use of a %BH-index cutoff value of 37.l. CONCLUSION: SUVmax of FB PET should not be taken as accurate, especially in the lower lung area and for small pulmonary lesions. BH PET/CT is expected to enable precise measurement of SUVmax and is thus recommended as part of the standard protocol for lung cancer.     

Assessment of inflammatory jaw pathologies using bone SPECT/CT maximum standardized uptake value

Objectives:To investigate the assessment of inflammatory jaw pathologies using bone single-photon emission CT-CT (SPECT/CT) maximum standardized uptake value (SUV_max).Methods:44 patients with inflammatory jaw pathologies (7 chronic osteomyelitis, 8 osteoradionecrosis and 29 medication-related osteonecrosis of the jaw (MRONJ)) underwent SPECT/CT at 4 h after injection of ^99mTc hydroxymethylene diphosphonate. The SPECT/CT parameters SUV_max of the inflammatory jaw pathologies were analyzed. Statistical analyses for the SUV_max were performed by one-way repeated measures analysis of variance with Tukey''s honestly significant difference test. A p-value lower than 0.05 was considered statistically significant.Results:The mean and standard deviation of SUV_max for 7 chronic osteomyelitis, 8 osteoradionecrosis and 29 MRONJ were 24.94 ± 3.65, 12.27 ± 5.47 and 16.55 ± 9.12, respectively. The SUV_max for chronic osteomyelitis were significantly higher than those for osteoradionecrosis (p = 0.011) and MRONJ (p = 0.043).Conclusions:Bone SPECT/CT SUV_max in the uptake of ^99mTc hydroxymethylene diphosphonate reflecting bone physiological changes for chronic osteomyelitis were significantly higher than those of osteonecrosis, such as osteoradionecrosis and MRONJ. Bone SPECT/CT SUV_max should be useful for the assessment of inflammatory jaw pathologies, such as chronic osteomyelitis, osteoradionecrosis and MRONJ.     

Non-invasive estimation of the net influx constant using the standardized uptake value for quantification of FDG uptake of tumours

To reduce the variability of the standardized uptake value (SUV) which is widely used to evaluate 2-[¹⁸F]fluoro-2-deoxy-d-glucose (FDG) uptake by neoplasms, net influx constant (Ki) was derived from SUV. The relationship Ki=SUV·k_p·V ₀, where k _p is the plasma clearance rate and V ₀ is the initial distribution volume of FDG, was utilized. A total of 71 plasma input functions were measured up to 60 min after intravenous injection of FDG in 55 patients and were analysed to obtain k _p and V ₀. SUV and V ₀ were calculated based on either body weight or body surface area. To validate the Ki estimation, another group of eight patients with squamous cell carcinoma of the head and neck was included. Parametric images of the net influx constant were obtained by Patlak graphical analysis of dynamic positron emission tomography (PET) data and measured plasma input function. V ₀ based on body weight was 0.1627±0.0329 (ml/g) and showed a weak negative correlation with body weight (y=0.23356–0.00138x, r=0.591). V ₀ based on body surface area was 5540±871 (ml/m²) and had no significant correlation with body weight. k _p at 50 min post injection was 0.03272±0.00243 (1/min), and had no correlation with the plasma glucose concentration. A highly significant positive correlation was noted between true Ki and estimated Ki based on both body weight (y=0.0033+1.0371x, r ²=0.897), and body surface area (y=0.0033+1.0351x, r ²=0.926). Ki, a better indicator of FDG uptake by tumour than SUV, is derivable non-invasively. Quantification of FDG uptake by Ki will aid standardization of diagnostic criteria of FDG PET oncology. Received 1 December 1997 and in revised form 9 February 1998     

Verification of the tumor volume delineation method using a fixed threshold of peak standardized uptake value

We aimed to determine the difference in tumor volume associated with the reconstruction model in positron-emission tomography (PET). To reduce the influence of the reconstruction model, we suggested a method to measure the tumor volume using the relative threshold method with a fixed threshold based on peak standardized uptake value (SUV_peak). The efficacy of our method was verified using ¹⁸F-2-fluoro-2-deoxy-d-glucose PET/computed tomography images of 20 patients with lung cancer. The tumor volume was determined using the relative threshold method with a fixed threshold based on the SUV_peak. The PET data were reconstructed using the ordered-subset expectation maximization (OSEM) model, the OSEM + time-of-flight (TOF) model, and the OSEM + TOF + point-spread function (PSF) model. The volume differences associated with the reconstruction algorithm (%VD) were compared. For comparison, the tumor volume was measured using the relative threshold method based on the maximum SUV (SUV_max). For the OSEM and TOF models, the mean %VD values were ?0.06 ± 8.07 and ?2.04 ± 4.23% for the fixed 40% threshold according to the SUV_max and the SUV_peak, respectively. The effect of our method in this case seemed to be minor. For the OSEM and PSF models, the mean %VD values were ?20.41 ± 14.47 and ?13.87 ± 6.59% for the fixed 40% threshold according to the SUV_max and SUV_peak, respectively. Our new method enabled the measurement of tumor volume with a fixed threshold and reduced the influence of the changes in tumor volume associated with the reconstruction model.     

Preoperative [18F]FDG PET/CT maximum standardized uptake value predicts recurrence of uterine cervical cancer

Purpose  

To determine if preoperative [¹⁸F]FDG-PET/CT imaging has prognostic significance in patients with uterine cervical cancer.     

18F-FDG PET/CT显像SUVmax与嗜铬细胞瘤恶性程度的相关性探讨

目的 分析嗜铬细胞瘤18 F-FDG PET/CT显像SUVmax与血浆游离甲氧基肾上腺素(MN)、甲氧基去甲肾上腺素(NMN)及131I-间位碘代苄胍(MIBG) SPECT显像间的关系,探讨18F-FDG PET/CT在诊断嗜铬细胞瘤和预测嗜铬细胞瘤恶性程度中的价值.方法 采用回顾性研究方法,收集经18F-FDG PET/CT检查且手术病理证实为嗜铬细胞瘤的患者19例,按其生物学行为分为良性组(n=11)与恶性组(n=8),查询PET/CT检查前后血MN、NMN及131 I-MIBG SPECT的检查结果,利用SPSS 17.0软件行两独立样本t检验,并绘制ROC曲线,探讨嗜铬细胞瘤SUVmax的特点,比较分析各检查之间的关系.结果 (1)11例良性嗜铬细胞瘤(BPCC)与8例恶性嗜铬细胞瘤(MPCC)PET/CT显像均为阳性;MPCC的SUVmax(19.40±7.39)明显大于BPCC的SUVmax (7.44±4.47),t=-4.40,P＜0.01;用约登指数法,确定SUVmax=8.85为判断嗜铬细胞瘤良恶性的分界值,其灵敏度、特异性和准确性分别为8/8、81.8％(9/11)、89.5％ (17/19);异位嗜铬细胞瘤SUVmax为19.75±8.64,明显高于肾上腺嗜铬细胞瘤SUVmax (9.12±5.83),t=-3.18,P＜0.05;初发与复发的嗜铬细胞瘤SUVmax间差异无统计学意义(t=-1.68,P＞0.05).(2)MN阴性病例SUVmax( 13.57±8.61)明显高于MN阳性病例SUVmax (6.63±2.42),t =2.70,P＜0.05;NMN阴性与阳性的病例SUVmax间差异无统计学意义(t=-0.93,P＞0.05).(3)7例同期行18F-FDG PET/CT与131I-MIBG SPECT患者中,3例BPCC,其中2例MIBG显像阳性,4例MPCC MIBG显像均为阴性;7例PET/CT显像均为阳性.结论 对于血MN与MIBG检查为阴性、但临床疑为嗜铬细胞瘤患者,FDG PET/CT可作为辅助诊断手段,减少漏诊率.     

Glucose-normalized standardized uptake value from (18)F-FDG PET in classifying lymphomas.

Our objective was to derive the best glucose sensitivity factor (g-value) and the most discriminating standardized uptake value (SUV) normalized to glucose for classifying indolent and aggressive lymphomas. METHODS: The maximum SUV obtained from (18)F-FDG PET over the area of biopsy in 102 patients was normalized by serum glucose ([Glc]) to a standard of 100 mg/dL. Discriminant analysis was performed by using each SUV(100) (SUV x {100/[Glc]}(g), calculated using various g-values ranging from -3.0 to 0, one at a time) as a variable against the lymphoma grades, and plotting the percentage of correct classifications against g (g-plot) to search for the best g-value in normalizing SUV(100) for classifying grades. To address the influence of the extreme glucose conditions, we repeated the same analyses in 12 patients with [Glc] < or = 70 mg/dL or [Glc] > or = 110 mg/dL. RESULTS: SUV(100) correctly classified lymphoma grades ranging from 62% to 73% (P < 0.0005), depending on the g-value, with a maximum at a g-value of -0.5. For the subgroup with extreme glucose values, the g-plot also revealed higher and more optimal discrimination at a g-value of -0.5 (92%) than at a g-value of 0 (83%) (P = 0.03). The discrimination deteriorated at g < -1 in both analyses. The box plot for all cases using a g-value of -0.5 showed little overlap in classifying lymphoma grades. For a visually selected threshold SUV(100) of 7.25, the sensitivity, specificity, and accuracy of identifying aggressive grades were 82%, 79%, and 81%, respectively. CONCLUSION: The results suggest that metabolic discrimination between lymphoma grades using a glucose-normalized SUV from (18)F-FDG PET is improved by introducing g-value as an extra degree of freedom.     

Reproducibility of standardized uptake value measurements determined by 18F-FDG PET in malignant tumors

18F-FDG PET is increasingly being used to monitor the early response of malignant tumors to chemotherapy. Understanding the reproducibility of standardized uptake values (SUVs) is an important prerequisite in estimating what constitutes a significant change. METHODS: Twenty-six patients were studied on 2 separate occasions (mean interval +/- SD, 3 +/- 2 d; range, 1-5 d). A static PET/CT scan was performed 94 +/- 9 min after the intravenous injection of 383 +/- 15 MBq of 18F-FDG. Mean and maximum SUVs (SUVmean and SUVmax, respectively) were determined for regions of interest drawn around the tumor on the first study and for the same regions of interest transferred to the second study. RESULTS: SUVmean in tumors ranged from 1.49 to 17.48 and SUVmax ranged from 2.99 to 24.09. The correlation between SUVmean determined on the 2 separate visits was 0.99; the mean difference between the 2 measurements was 0.01 +/- 0.27 SUV. The 95% confidence limits for the measurements were +/-0.53. For SUVmax, the mean difference was -0.05 +/- 1.14 SUV. CONCLUSION: Our study demonstrates that repeated measurements of SUVmean performed a few days apart are highly reproducible. A decrease of 0.5 in the SUV is statistically significant.     

FDG PET/CT and diffusion-weighted imaging for breast cancer: prognostic value of maximum standardized uptake values and apparent diffusion coefficient values of the primary lesion

Purpose  

To correlate both primary lesion ¹⁸F-fluorodeoxyglucose (FDG) maximum standardized uptake value (SUVmax) and diffusion-weighted imaging (DWI) apparent diffusion coefficient (ADC) with clinicopathological prognostic factors and compare the prognostic value of these indexes in breast cancer.     

^18F-FDG符合线路显像最大标准摄取值在胃癌评估中的价值

目的研究^18F—FDG符合线路显像SUVmax在胃癌评估中的意义。方法回顾性分析92例胃部疾病患者[男60例,女32例,平均年龄65（32～85）岁;其中胃癌78例]。78例胃癌中,残胃癌3例、原发性胃癌75例（Eis期4例、T1期13例、T2期9例、T3期33例、T4期11例,5例未手术）;高分化腺癌22例,中分化腺癌15例,低分化腺癌28例。采用ROI技术分析图像并计算SUVmax,分别用视觉法与SUVmax分析^18F—FDG符合线路显像资料,并以组织病理学或活组织检查结果为标准计算两者检验效能。使用ROC曲线分析评价SUVmax;采用Pearson相关分析评估SUVmax与病灶大小的关系,Wilcoxon秩和检验分析SUVmax在进展期胃癌和早期胃癌的差异,Kruskal—Wallis检验分析SUVmax与不同分化程度腺癌的关系。结果^18F—FDG符合线路显像视觉法与SUVmax诊断胃癌的灵敏度均为64．1％（50／78）,特异性均为64．3％（9／14）,准确性均为64．1％（59／92）。SUVmax ROCAUC为0．695,最佳临界值为0．700;SUVmax与病灶最大径呈正相关（r=0．489,P〈0．001）,Tis-1期病灶SUVmax（0．676±1．288）与L～4期SUVmax（3．851±3．764）差异有统计学意义（Z=-3．754,P〈0．001）,而高、中、低分化腺癌间SUVmax（分别为2．805±4．008,3．447±2．365,3．413±3．737）差异无统计学意义（X2=2．459,P〉0．05）。结论在^18F-FDG符合线路显像评估胃癌中,SUVmax较视觉法提供了更多的信息,但其与胃癌T分期、组织学类型、分化程度等的关系需进一步研究。     

18F-FDG PET/CT最大标准摄取值联合HRCT在肺癌诊断中的价值和影响因素分析

目的 探讨18F-FDG PET/CT联合高分辨率CT(HRCT)诊断肺癌的价值和主要影响因素.方法 回顾分析2010年8月至2011年8月因肺实性病灶行18F-FDG PET/CT检查及肺部HRCT扫描的122例患者资料,所有病例均经病理证实或影像学检查随访8个月以上确诊.利用x2检验对HRCT上不同影像特征在良恶性病变中的构成比差异进行比较,单因素方差分析比较不同病理类型病灶的SUVmax差异,多因素logistic回归分析SUVmax及HRCT影像特征等影响因素,探讨最佳SUVmax诊断界值和18F-FDG PET/CT对肺癌的诊断价值.结果 122例肺实性病灶患者中,恶性82例,良性40例.肺癌HRCT影像特征中前3位依次为毛刺征64.6％ (53/82)、分叶征63.4％(52/82)和胸膜牵拉征39.0％(32/82),高于在良性病变中的比例(x2=19.08、30.89、10.88,均P＜0.01).肺部鳞状细胞癌(简称鳞癌)、小细胞癌和腺癌的SUVmax依次为12.57±4.34、10.66±2.90和8.19±6.01,与肺部良性病变SUVmax (3.01±3.62)相比差异有统计学意义(F =20.83,P＜0.01).不同病理类型肺癌SUVmax从大到小依次为鳞癌、小细胞癌和腺癌,其中鳞癌与腺癌SUVmax差异有统计学意义(P＜0.01);SUVmax的ROC AUC为0.863,SUVmax界值2.99和2.50对肺癌诊断的灵敏度、特异性分别为89.0％(73/82)、75.0％ (30/40)和91.5％ (75/82)、65.0％(26/40);诊断一致性SUVmax 2.99优于SUVmax 2.50,Kappa值分别为0.644和0.597.多因素logistic回归分析显示SUVmax 2.99的诊断比值比(OR)优于SUVmax 2.50的OR,分别为5.42和3.93;SUVmax (OR=5.42,P=0.01)、肿瘤最大径(OR=7.27,P=0.02)、毛刺征(OR =7.70,P＜0.01))和分叶征(OR=12.38,P＜0.01)均为肺癌与良性病灶鉴别诊断有统计学意义的影响因素.结论 SUVmax对肺癌的诊断和鉴别诊断有较高价值.18F-FDGPET/CT联合HRCT诊断肺实性病灶时,SUVmax、肿瘤最大径、毛刺征和分叶征为其鉴别诊断的主要影响因素.     

FDG PET of primary benign and malignant bone tumors: standardized uptake value in 52 lesions

PURPOSE: To evaluate the standardized uptake value (SUV) of 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) at positron emission tomography (PET) in the differentiation of benign from malignant bone lesions. MATERIALS AND METHODS: Fifty-two (19 malignant, 33 benign) primary bone lesions were examined with FDG PET prior to tissue diagnosis. The SUVs were calculated and compared between benign and malignant lesions and among histologic subgroups that included more than four cases. RESULTS: There was a statistically significant difference in SUV between benign (2.18 +/- 1.52 [SD]) and malignant (4.34 +/- 3.19) lesions in total (P =.002). However, giant cell tumors (n = 5; SUV, 4.64 +/- 1.05) showed significantly higher SUV than chondrosarcomas (n = 7; SUV, 2.23 +/- 0.74) (P =.036, adjusted for multiple comparisons) and had no statistically significant difference in SUV compared with osteosarcomas (n = 6; SUV, 3.07 +/- 0.96) (P =.171). There was no statistically significant difference in SUV between fibrous dysplasias (n = 6; SUV, 2.05 +/- 0.98) and osteosarcoma (P =.127) or chondrosarcomas (P =.667). Although the number of cases was small, three chondroblastomas, one sarcoidosis, and one Langerhans cell histiocytosis showed levels of FDG accumulation as high as that of osteosarcomas. CONCLUSION: Radiologists should be aware of the high accumulation of FDG in some benign bone lesions, especially histiocytic or giant cell-containing lesions. Consideration of histologic subtypes should be included in analysis of SUV at FDG PET of primary bone tumors.     

Accuracy of standardized uptake value measured by simultaneous emission and transmission scanning in PET oncology.

We assessed the accuracy of the standardized uptake value (SUV) measured by simultaneous emission and transmission scanning in cancer patients using FDG positron emission tomography (PET). Conventional, independent emission (E)/transmission (T) scans and simultaneous E/T scans were conducted consecutively in 30 patients who underwent FDG PET examinations. The SUVs of 35 mass lesions and 34 selected normal tissues were derived from the independent E/T scan and simultaneous E/T scan. Experimental studies using a cylindrical phantom were also conducted to evaluate the accuracy and reproducibility of the SUV derived from a simultaneous E/T scan. The SUVs of 18F solution in the phantom were estimated to be approximately 1, with high reproducibility in the range of total counts observed in the clinical examinations. There were no significant differences in the SUVs in 35 tumours derived from simultaneous E/T scans and those derived from independent scans, and there was a strong positive correlation between the two (r = 0.99, P < 0.01). There were also no significant differences in the SUVs in 34 normal tissue regions derived from simultaneous E/T scans and those derived from independent scans. In conclusion, simultaneous E/T scanning with FDG in patients with malignant tumours is a valid method, since the SUV derived from the simultaneous scan is accurate and reproducible.     

Accuracy of PET for diagnosis of solid pulmonary lesions with 18F-FDG uptake below the standardized uptake value of 2.5.

Benign and malignant pulmonary lesions usually are differentiated by 18F-FDG PET with a semiquantitative 18F-FDG standardized uptake value (SUV) of 2.5. However, the frequency of malignancies with an SUV of <2.5 is significant, and pulmonary nodules with low 18F-FDG uptake often present diagnostic challenges. METHODS: Among 360 consecutive patients who underwent 18F-FDG PET to evaluate pulmonary nodules found on CT, we retrospectively analyzed 43 who had solid pulmonary lesions (excluding lesions with ground-glass opacity, infiltration, or benign calcification) with an SUV of <2.5. The uptake of 18F-FDG was graded by a visual method (absent, faint, moderate, or intense) and 2 semiquantitative methods (SUV and contrast ratio [CR]). Final classification was based on histopathologic findings or at least 6 mo of clinical follow-up. RESULTS: We found 16 malignant (diameter, 8-32 mm) and 27 benign (7-36 mm) lesions. When faint visual uptake was the cutoff for positive 18F-FDG PET results, the receiver-operating-characteristic (ROC) analysis correctly identified all 16 malignancies and yielded false-positive results for 10 of 27 benign lesions. Sensitivity was 100%, specificity was 63%, and the positive and negative predictive values were 62% and 100%, respectively. When an SUV of 1.59 was the cutoff for positive 18F-FDG PET results, the ROC analysis revealed 81% sensitivity, 85% specificity, and positive and negative predictive values of 77% and 89%, respectively. At a cutoff for positive 18F-FDG PET results of a CR of 0.29, the ROC analysis revealed 75% sensitivity, 82% specificity, and positive and negative predictive values of 71% and 85%, respectively. The areas under the curve in ROC analyses did not differ significantly among the 3 analyses (visual, 0.84; SUV, 0.81; and CR, 0.82). Analyses of intra- and interobserver variabilities indicated that visual and SUV analyses were quite reproducible, whereas CR analysis was poorly reproducible. CONCLUSION: These results suggested that for solid pulmonary lesions with low 18F-FDG uptake, semiquantitative approaches do not improve the accuracy of 18F-FDG PET over that obtained with visual analysis. Pulmonary lesions with visually absent uptake indicate that the probability of malignancies is very low. In contrast, the probability of malignancy in any visually evident lesion is about 60%.     

FDG PET/CT对肝细胞癌早期动态血流和延迟标准化摄取值的测定

目的前瞻性研究18F-FDG PET/CT早期动态血流指标是否有助于发现肝细胞癌(HCC),分析有或无血管浸润的HCC特征,评价HCC在FDG PET/CT中血流与代谢的关系。材料与方法本研究经伦理委员会批准,所有病人均签署