Microvessel density: correlation with 18F-FDG uptake and prognostic impact in lung adenocarcinomas.

Although researched for many years, the prognostic value of tumor angiogenesis reflected by microvessel density (MVD) is still controversial, and there have been no previous reports regarding the correlation with 18F-FDG uptake in lung adenocarcinomas. Therefore, in the present study, we investigated the correlation between MVD determined with different endothelial cell antibodies and 18F-FDG uptake and compared the prognostic impact of those factors in lung adenocarcinomas. METHODS: Forty-four patients with 45 lung adenocarcinomas underwent 18F-FDG PET before surgery. Consecutive paraffin-embedded sections obtained from each resected tumor were immunostained for CD31 (a panendothelial cell marker), CD105 (a proliferation-related endothelial cell marker), and CD34/alpha-SMA (for double labeling of endothelial cells and mural cells). Four high-power fields in the area with the highest MVD were selected for analysis. Computer-assisted image analysis was used to assess MVD. RESULTS: MVD staining results for panendothelial cell markers can be classified into 3 microvessel patterns: diffuse, alveolar, and mixed. The highly ordered alveolar pattern is believed to represent preexisting alveolar vessels trapped in lung adenocarcinomas and may have no significant meaning for the aggressiveness of tumors. Preexisting alveolar cells also do not contribute to 18F-FDG uptake. CD105 staining of MVD (CD105-MVD) showed a significantly positive correlation with 18F-FDG uptake (P < 0.0001), whereas CD31 staining of MVD (CD31-MVD) showed a marginally negative correlation with it (P = 0.057). Although CD105-MVD correlated negatively with prognosis, patients with low CD105-MVD, compared with those with high or moderate CD105-MVD, had a much better prognosis in both disease-free and overall survival analyses (P = 0.017 and P = 0.013, respectively). Patients with low CD31-MVD had the worst prognosis (P = 0.032 for disease-free survival analysis and P = 0.179 for overall survival analysis). CONCLUSION: There is no positive correlation between 18F-FDG uptake and MVD determined with panendothelial cell markers (CD31 and CD34); in contrast, there is a marginally negative correlation between them. MVD determined with CD105, which is a proliferation-related endothelial cell marker, reflects active angiogenesis, correlates positively with 18F-FDG uptake, and is a better indicator of prognosis in lung adenocarcinomas.     

18F-FDG uptake in breast cancer correlates with immunohistochemically defined subtypes

Objectives

To determine whether a correlation exists between maximum standardized uptake value (SUV_max) on ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) and the subtypes of breast cancer.

Methods

This retrospective study involved 548 patients (mean age 51.6 years, range 21–81 years) with 552 index breast cancers (mean size 2.57 cm, range 1.0–14.5 cm). The correlation between ¹⁸F-FDG uptake in PET/CT, expressed as SUV_max, and immunohistochemically defined subtypes (luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) positive and triple negative) was analyzed.

Results

The mean SUV_max value of the 552 tumours was 6.07?±?4.63 (range 0.9–32.8). The subtypes of the 552 tumours were 334 (60 %) luminal A, 66 (12 %) luminal B, 60 (11 %) HER2 positive and 92 (17 %) triple negative, for which the mean SUV_max values were 4.69?±?3.45, 6.51?±?4.18, 7.44?±?4.73 and 9.83?±?6.03, respectively. In a multivariate regression analysis, triple-negative and HER2-positive tumours had 1.67-fold (P?<?0.001) and 1.27-fold (P?=?0.009) higher SUV_max values, respectively, than luminal A tumours after adjustment for invasive tumour size, lymph node involvement status and histologic grade.

Conclusion

FDG uptake was independently associated with subtypes of invasive breast cancer. Triple-negative and HER2-positive breast cancers showed higher SUV_max values than luminal A tumours.

Key Points

? ¹⁸ F-FDG PET demonstrates increased tissue glucose metabolism, a hallmark of cancers. ? Immunohistochemically defined subtypes appear significantly associated with FDG uptake (expressed as SUV _max ). ? Triple-negative tumours had 1.67-fold higher SUV _max values than luminal A tumours. ? HER2-positive tumours had 1.27-fold higher SUV _max values than luminal A tumours.     

Pattern of uptake and excretion of (18)F-FDG in the lactating breast.

Excretion of radiopharmaceuticals into breast milk poses a potential risk to infants and clear recommendations regarding interruption times are required. There are few data available regarding the impact of (18)F-FDG on this issue. With increasing use of PET for oncologic imaging and its potential advantages to nursing mothers because of its short physical half-life compared with other commonly used tumor imaging agents such as (67)Ga and (201)Tl, evaluation of the excretion pattern of this agent in breast milk is important. METHODS: We have evaluated the uptake of FDG in the breasts in 7 women, 6 of whom were lactating and 1 of whom was in early postpartum but had not commenced breast-feeding. Milk samples were obtained from 4 of the lactating women, including serial samples from 1. RESULTS: Significantly increased breast uptake was identified in all lactating breasts but not in 1 breast consistently refused by the nursing infant or in the woman who had not begun breast-feeding after delivery of her child. No qualitative change or semiquantitative estimate of radiotracer uptake in the breast was seen after expression of breast milk. Decay-corrected activity measurable in breast milk ranged from 5.54 to 19.3 Bq/mL/MBq injected. Using a standard model of breast-feeding, the calculated maximum cumulative dose to the infant, 0.085 mSv with no interruption of breast-feeding, is well below the recommended limit of 1 mSv. CONCLUSION: High uptake of FDG in the lactating breast appears to be related to suckling. There is, however, little secretion of activity into breast milk. Accordingly, a higher radiation dose is received by the infant from close contact with the breast than from ingestion of radioactive milk.     

脑脓肿高度摄取18F-FDG

患者男 ,５１岁 ,因“书写、语文、计算能力下降１０天伴头痛３天”于２００１年３月２１日入院。患者入院前２０天患上颌窦炎 ,服红霉素、甲硝唑等药后 ,症状有所好转 ,１０天前开会作记录时 ,突感手指僵硬、书写能力下降、继之语言迟钝 ,３天前出现头痛。入院时神清 ,但口齿不清 ,答不切题 ,计算、书写能力差。入院后查ＭＲＩ示左颞叶大片长Ｔ１、长Ｔ２ 信号 ,信号不均 ,边界尚清 ,中间可见一环状等Ｔ１、等Ｔ２ 信号影 ,增强扫描呈不规则环状强化 ,大小３ｃｍ×３ｃｍ×３．８ｃｍ ,左颞叶脑沟消失 ,左侧脑室变小 ,中线结构右移。两侧上…     

Association of vascular 18F-FDG uptake with vascular calcification.

Both calcification and FDG uptake have been advocated as indicators of atheroma. Atheromas calcify as cells in the lesion undergo apoptosis and necrosis during evolution of the lesion and at the end stage of the lesion. FDG concentrates in lesions due to the relatively dense cellularity in regions of inflammation of active atheromas. This investigation examines the geographic relationship of focal vascular (18)F-FDG uptake, as a marker of atherosclerotic inflammation, to arterial calcification detected by contemporaneous CT. METHODS: We reviewed PET/CT images from 78 patients who were referred for tumor staging for the presence of vascular (18)F-FDG uptake and vascular calcification. Arterial wall (18)F-FDG accumulation greater than adjacent blood-pool activity was considered inflammation. Arterial attenuation of >130 Hounsfield units was considered calcification. Sites in the ascending and descending aorta, the carotid and iliac arteries, and the coronary territories were examined on the emission, CT, and fusion images on a point-by-point basis. When lesions were seen, we evaluated whether they were overlapping or discrete. RESULTS: The (18)F-FDG arterial distribution was consistent with established atherosclerotic topography, with increased uptake in the thoracic aorta, at the carotid bifurcation, and in the proximal coronary vessels. Arteries typically displayed a patchwork of normal vessel, focal inflammation, or calcification; inflammation and calcification overlapped in <2% of cases. Arterial inflammation preceded calcification, in terms of mean patient age. Coronary inflammation was more prevalent in patients with more cardiovascular risk factors. CONCLUSION: Vascular calcification and vascular metabolic activity rarely overlap, suggesting these findings represent different stages in the evolution of atheroma.     

Within-patient variability of (18)F-FDG: standardized uptake values in normal tissues.

The aim of this study was to evaluate the test-retest variability of standardized uptake values (SUVs) in normal tissues and the impact of various methods for measuring the SUV. METHODS: SUVs were determined in 70 cancer-free patients (40 female and 30 male) on 2 occasions an average of 271 d apart. Mean values for body weight and height, blood glucose level, injected dose, and uptake period did not change between the 2 groups of studies. Four regions of interest (ROIs) were placed-on the liver, lung, mediastinum, and trapezius muscle. Mean and maximum SUVs normalized for body weight were obtained, and normalizations were then applied for lean body mass (LBM), LBM and blood glucose level, body surface area (BSA), and BSA and blood glucose level. RESULTS: In the lungs and muscle, metabolic activity within the ROIs was significantly different in the 2 studies, no matter which method was used for the SUVs. The differences ranged from 0.02 to 0.1 for SUV normalized for body weight and SUV normalized for LBM and from 0.001 to 0.002 for SUV normalized for BSA. In the liver, results were similar for all SUVs, except for maximum SUV corrected for LBM and maximum SUV corrected for LBM and blood glucose level. The metabolic activity measured in the mediastinum was also comparable in the 2 studies, regardless of the type of SUV. When investigating whether any normalization method for SUVs reduces variability and improves test-retest concordance, we found no significant superiority for any. The best intraclass correlation coefficients were obtained with the SUV normalized for body weight, in both the liver and the mediastinum, but the coefficients of variation were similar for all 3 mean SUVs that were not corrected for glucose level (range, 10.8%-13.4%). However, normalizing for blood glucose level increased the variability and decreased the level of concordance between studies. CONCLUSION: The SUVs measured in normal liver and mediastinum in cancer-free patients are stable over time, no matter which normalization is used. Correcting for blood glucose level increases the variability of the values and should therefore be avoided. Normalizing for BSA or LBM does not improve the reproducibility of the measurements.     

Evaluation of 18F-FDG uptake and arterial wall calcifications using 18F-FDG PET/CT.

Glucose metabolic activity expressed as (18)F-FDG uptake may be increased in active atherosclerotic plaque. Calcium depositions are often increased in mature atherosclerotic plaque. The purpose of the present study was to assess the patterns of vascular-wall (18)F-FDG uptake and CT calcifications using combined PET/CT. METHODS: One hundred twenty-two consecutive patients over the age of 50 (47 women and 75 men; mean age, 66 +/- 9 y) undergoing whole-body (18)F-FDG PET/CT for tumor assessment were retrospectively evaluated. PET, CT, and PET/CT slices were generated for review. Abnormal vascular findings in major arteries in the chest and abdomen were categorized as PET positive (PET+), PET negative (PET-), CT positive (CT+), or CT negative (CT-). The topographic relationship between increased vascular-wall (18)F-FDG uptake on PET and the presence of calcifications on CT was assessed on PET/CT fused images, with abnormal sites further classified as PET+/CT+, PET+/CT-, or PET-/CT+. The presence of CT calcifications and increased vascular-wall (18)F-FDG uptake was correlated with age, sex, presence of cardiovascular risk factors, and cardiovascular disease. RESULTS: Abnormal findings were identified at 349 sites. CT calcifications (CT+) were observed at 320 sites (92%) of 100 patients (82%), more commonly in men (P < 0.03), in older patients (P < 0.0001), in patients with hypertension (P < 0.003) or hyperlipidemia (P < 0.04), and in smokers (P < 0.008). Increased vascular-wall (18)F-FDG uptake (PET+) was observed at 52 sites (15%) of 38 patients (31%), more commonly in men (P < 0.02), in older patients (P < 0.0001), and in patients with hypertension (P < 0.02), and was borderline in patients with cardiovascular disease (P = 0.057). PET+ and CT+ findings correlated in 12 patients, a PET+/CT- pattern was found in 18 patients, and 8 patients had increased vascular-wall (18)F-FDG uptake in sites with and without calcifications (PET+/CT+, CT-). Twenty-two patients (18%) had a PET-/CT- pattern. CONCLUSION: Hybrid PET/CT can be used to identify and to correctly localize vascular-wall (18)F-FDG activity. Increased vascular-wall (18)F-FDG activity was found in 15% of sites and CT calcifications were noted in 92% of sites, with congruent findings in 7%. The clinical significance of the relationship between vascular-wall (18)F-FDG uptake and CT calcifications needs to be assessed by further prospective studies with long-term follow up.     

Increased 18F-FDG uptake in degenerative disease of the spine: Characterization with 18F-FDG PET/CT.

We determined the prevalence of abnormal spinal 18F-FDG uptake and assessed the relationship between the severity of findings on 18F-FDG PET and the severity of degenerative spinal disease (DSD) on CT. METHODS: PET/CT scans of 150 patients >18 y old, referred for whole-body 18F-FDG PET/CT for evaluation of known or suspected malignancy from June to July 2002, were analyzed retrospectively for the presence of increased 18F-FDG uptake in the spine and for anatomic correlates. Initially, PET images were examined and foci of 18F-FDG uptake in the spine were graded on a 0-4 scale based on intensity of 18F-FDG uptake (0 = definitely normal, 1 = probably normal, 2 = equivocal, 3 = probably abnormal, 4 = definitely abnormal). From PET alone, an impression as to whether lesions were most likely metastases or degenerative, as well the level of the spine involved, was also recorded. CT images of all 150 patients were reviewed independently by a musculoskeletal radiologist, who was unaware of patient identification, history, and findings of other imaging modalities, with the location recorded and severity graded on a 4-point-scale (0 = normal, 1 = mild, 2 = moderate, 3 = severe for both degenerative disk and facet disease). The relationship between PET and CT findings was then determined. RESULTS: Of the 150 patients, 63 (42.0%) had no abnormal findings in the spine on PET (grade 0), 27 (18.0%) had grade 1, 25 (16.7%) had grade 2, 17 (11.3%) had grade 3, and 16 patients (10.7%) had grade 4 18F-FDG uptake for DSD. Two additional patients had apparent spinal metastases with no degenerative changes. Five patients had metastases and DSD (included above). Of the patients who had abnormal spinal findings graded as probable or definite for DSD on CT (grades 3-4), 11 had abnormal findings in the cervical spine, 16 in the thoracic spine, and 23 patients in the lumbosacral spine. Seven patients (4.7%) had PET findings suggestive of spinal metastases. For patients with a maximum regional DSD score of 3, the mean 18F-FDG uptake for that spinal level was 1.4 +/- 1.5, whereas for patients with a maximum regional DSD score of 0, the mean PET grade was significantly lower at 0.4 +/- 0.9 (P = 0.0001). CONCLUSION: Incidental findings on PET suggestive of DSD are common (22% of patients), most common in the lumbosacral spine, and can be recognized on CT. The severity of PET findings correlates with the severity of degenerative disk and facet disease as graded by CT, likely due to the fact that the inflammatory process that accompanies DSD is evident on PET. Increased 18F-FDG uptake in DSD should not be confused with metastatic disease.     

Relationship between skeletal uptake of99mTc-HMDP and bone mineral density in elderly women

The relationship between bone mineral density in elderly women and the pattern of skeletal uptake of^99mTc-HMDP, especially in regard to skull uptake, was investigated. The whole-body skeletal uptake (WBSU) and whole-body skeletal tracer distribution patterns were studied in 86 disease-free women on bone scintigraphy with^99mTc-hydroxy-methylene-diphosphonate (HMDP). Bone scans were quantified by setting regions of interest (ROI) and bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry in all patients. WBSU and the skeletal distribution pattern were compared with bone mineral densities of the entire skeleton as well as selected regions. WBSU was high in the elderly and negatively correlated with regional bone mineral densities (r = ?0.403 to ?0.534). Among the regions, uptake by the skull increased with age more than in other regions in women and had the highest negative correlation with the bone mineral density. The skull uptake correlated negatively with total body BMD (r = ?0.583) and with lumbar BMD (r = ?0.561, p< 0.0001). Our results show that increased radionuclide uptake in bone scintigraphy, especially skull uptake was associated with decreased bone mineral density in elderly women, so that, increased skull uptake in elderly women would be a scintigraphic sign of post-menopausal or senile osteopenia.     

18F-FDG uptake in diffuse peritoneal lymphomatosis

A 38-year-old man presented with declining appetite and progressive abdominal distention. Abdominal ultrasonography revealed omental and bowel wall thickening. Histopathologic examination showed a high-grade lymphoblastic Burkitt-like B-cell lymphoma. 18F fluorodeoxyglucose positron emission tomography/computed tomography images showed diffusely increased metabolic activity in the thickened omentum, intestines, mesentery, and peritoneum (omental caking). Diffuse peritoneal and omental seeding are well-known forms of dissemination of metastatic carcinoma. However, omental and peritoneal lymphomatosis are rare manifestations of high-grade lymphomas. This uncommon case demonstrates usefulness of F-18 fluorodeoxyglucose positron emission tomography/computed tomography in omental and peritoneal involvement in lymphoma.     

~(18)F-FDGPET/CT棕色脂肪摄取的影像学分析

目的:分析18F-FDG PET/CT检查中棕色脂肪组织(BAT)摄取的规律和特点,以避免不必要的误诊。方法:回顾性分析行PET/CT全身检查的2350例受检者的图像。结果:34例(1.44%)有不同程度BAT摄取,其中恶性肿瘤患者9例(甲状腺癌术后4例)。BAT显影主要在寒冷季节出现,女性比例(2.57%)高于男性(0.76%);特征性表现为对称性分布于肩颈部、锁骨上区、脊柱两旁、纵隔、肾上腺及肾周区的高摄取灶,SUVmax为7.18±4.27。BAT显影部位的数目与摄取的SUVmax呈正相关(r=0.78,P<0.05);5例检查者进行了延迟扫描,延迟后BAT分布、形态无明显变化,SUVmax显著升高(P<0.05)。4例甲状腺癌术后复查病例的BAT摄取不同程度影响了对区域淋巴结的观察。结论:BAT摄取的分布及影像表现具有一定的特征性,显影部位越多,SUVmax越大,延迟扫描后SUVmax显著升高,容易干扰对显影区域病灶的观察。     

18F-FDG uptake in the normal appendix in adults: PET/CT evaluation

Annals of Nuclear Medicine - This study aimed to determine the level of 18F fluorodeoxyglucose (18F-FDG) activity in the normal adult appendix using positron emission tomography/computed tomography...     

Different glucose uptake and glycolytic mechanisms between hepatocellular carcinoma and intrahepatic mass-forming cholangiocarcinoma with increased (18)F-FDG uptake.

(18)F-FDG uptake in malignant tumors largely depends on the presence of facilitated glucose transporters, especially type 1 (Glut 1) and a rate-limiting glycolytic enzyme, hexokinase (HK) type II. Low expression of Glut 1 was reported in hepatocellular carcinoma (HCC), whereas high expression was found in cholangiocarcinoma. Immunohistochemistry and proteome analysis were performed to obtain a detailed evaluation of the mechanisms involved in glucose uptake and use in these tumors. METHODS: Tumor tissues obtained from both HCC (n = 7) and mass-forming cholangiocarcinoma patients (n = 7) who showed increased (18)F-FDG uptake on PET were used. Immunohistochemistry for Glut 1 and HK I-III was performed in all tumor tissues. To identify proteins that regulate carbohydrate metabolism, a proteome analysis with matrix-assisted laser desorption ionization-time of flight and enzymatic digestion in-gel were performed using 8 available tumor samples and 3 normal liver tissues. Of the 8 tumor samples, 4 were HCCs; one was an intermediate phenotype HCC, and 3 were cholangiocarcinomas. The spot intensity of the proteins was calculated using proteome data; the tissues then were divided into 2 groups on the basis of the protein expression pattern, because the protein expression pattern of the intermediate-phenotype HCC was close to that of the cholangiocarcinomas. Group A included the HCCs and group B included the intermediate-phenotype HCC as well as the cholangiocarcinomas. RESULTS: Immunoreactivity for Glut 1 was positive in all cholangiocarcinomas, but was negative in all HCCs except the one intermediate phenotype. However, HK II was positive in HCCs but was negative in 6 of the 7 cholangiocarcinomas. A total of 331 protein spots with a P value of <0.05 were identified by proteome analysis. Thirteen of these proteins that regulate carbohydrate metabolism were selected. The pentose phosphate pathway was increased in both groups, but more significantly in group B. Gluconeogenesis enzymes were decreased in both groups, but the tricarboxylic acid cycle-regulating enzyme expression was variable. CONCLUSION: HCCs have different glucose-regulating mechanisms from those of cholangiocarcinomas, even though both tumors showed increased (18)F-FDG uptake on PET scans. Further studies are required with regard to energy metabolism and (18)F-FDG uptake patterns in association with various oncogenic alterations regulating multiple steps of the glycolytic pathways.     

晚期乳腺癌18F-FDG PET-CT显像标准摄取值与预后的相关性

目的 探讨晚期乳腺癌18 F-FDG PET-CT显像标准摄取值与预后的相关性.方法 选择68例晚期乳腺癌患者,记录诊断时PET-CT的SUV值,均给予全身静脉化疗,以SUV值8为分界点,将本组患者分为两组,随访5年,观察SUV值与5年生存率的关系.结果 本组观察的68例患者,SUV值越小,生存期相对越长,反之,生存期则相对较短.结论 18F-FDG PET-CT显像标准摄取值(SUV值)对乳腺癌的预后有一定价值,值得临床进一步研究.     

Association between diffuse renal uptake of 18F-FDG and acute kidney injury

Annals of Nuclear Medicine - The aim of this study was to investigate the clinical characteristics of patients with diffuse renal uptake (DRU) of 2-deoxy-2-[F-18]fluoro-d-glucose (FDG), with...