Arterial spin labeling performs comparably to 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography for presurgical evaluation in pediatric lesional epilepsy.

How far is arterial spin labeling MRI from a clinical reality? Insights from arterial spin labeling comparative studies in Alzheimer's disease and other neurological disorders.

Surgical resection is the only curative treatment strategy for intrahepatic cholangiocarcinoma (CC). Therefore, accurate staging is essential for appropriate management of patients with CC. We assessed the usefulness of 2-[(18)F]fluoro-2-deoxy- d-glucose (FDG) positron emission tomography (PET) in the staging of CC. We undertook a retrospective review of FDG PET images in 21 patients (10 female, 11 male; mean age 57 years) diagnosed with CC. Ten patients had hilar CC and 11, peripheral CC. Patients underwent abdominal magnetic resonance imaging (MRI) ( n=20) and computed tomography (CT) ( n=12) for the evaluation of primary tumours, and chest radiography and whole-body bone scintigraphy for work-up of distant metastases. For semi-quantitative analysis, the maximum voxel standardised uptake value (SUV(max)) was obtained from the primary tumour. All peripheral CCs showed intensely increased FDG uptake, and some demonstrated ring-shaped uptake corresponding to peripheral rim enhancement on CT and/or MRI. In nine of the ten patients, hilar CCs demonstrated increased FDG uptake of a focal nodular or linear branching appearance. The remaining case was false negative on FDG PET. One patient with a false negative result on MRI demonstrated increased uptake on FDG PET. Among the ten hilar CCs, FDG uptake was intense in only two patients and was slightly higher than that of the hepatic parenchyma in the remaining patients. For the detection of lymph node metastasis, FDG PET and CT/MRI were concordant in 16 patients, and discordant in five (FDG PET was positive in three, and CT and MRI in two). FDG PET identified unsuspected distant metastases in four of the 21 patients; all of these patients had peripheral CC. FDG PET is useful in detecting the primary lesion in both hilar and peripheral CC and is of value in discovering unsuspected distant metastases in patients with peripheral CC. FDG PET could be useful in cases of suspected hilar CC with non-confirmatory biopsy and radiological findings.

The purpose of this study was to evaluate the impact of [18F]fluorodeoxy-D-glucose positron emission tomography (FDG-PET) on the primary staging of patients with small-cell lung cancer (SCLC). FDG-PET was performed in 120 consecutive patients with SCLC during primary staging. In addition, brain examinations with both FDG-PET and cranial magnetic resonance imaging (MRI) or computed tomography (CT) were performed in 91 patients. Results of FDG-PET were compared with those of conventional staging procedures. FDG-PET detected markedly increased FDG uptake in the primary tumours of all 120 patients (sensitivity 100%). Complete agreement between FDG-PET results and other staging procedures was observed in 75 patients. Differences occurred in 45 patients at 65 sites. In 47 sites the FDG-PET results were proven to be correct, and in ten, incorrect. In the remaining eight sites, the discrepancies could not be clarified. In 14/120 patients, FDG-PET caused a stage migration, correctly upstaging ten patients to extensive disease and downstaging three patients by not confirming metastases of the adrenal glands suspected on the basis of CT. Only 1/120 patients was incorrectly staged by FDG-PET, owing to failure to detect brain metastases. In all cases the stage migration led to a significant change in the treatment protocol. Sensitivity of FDG-PET was significantly superior to that of CT in the detection of extrathoracic lymph node involvement (100% vs 70%, specificity 98% vs 94%) and distant metastases except to the brain (98% vs 83%, specificity 92% vs 79%). However, FDG-PET was significantly less sensitive than cranial MRI/CT in the detection of brain metastases (46% vs 100%, specificity 97% vs 100%). The introduction of FDG-PET in the diagnostic evaluation of SCLC will improve the staging results and affect patient management, and may reduce the number of tests and invasive procedures.

2-[18F]Fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) and magnetoencephalography (MEG) may assist in identifying the epileptogenic zone in children with nonlesional localization-related epilepsy. The aim of this study was to evaluate sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FDG-PET, MEG, FDG-PET+MEG, and FDG-PET/MEG in children with nonlesional localization-related epilepsy. Twenty-six children with localization-related epilepsy and who had normal or subtle changes on magnetic resonance imaging (MRI) underwent FDG-PET and MEG. Twenty-two patients had surgical resection, and surgical outcome was assessed using Engel classification. In patients with Engel I seizure outcome, we assessed the sensitivity, specificity, PPV, and NPV of lobar localization of MEG, FDG-PET, FDG-PET+MEG, and FDG-PET/MEG. Sixteen (72.7%) of 22 had Engel I seizure outcome. MEG was concordant with surgical resection in 18 patients, 14 had Engel I, and four had Engel II-IV outcomes. MEG was nonlocalizing or nonconcordant in four patients; two patients had Engel I and two had Engel II-IV outcomes. FDG-PET was concordant with surgical resection in 14 patients; 9 had Engel I outcome, and 5 had Engel II-IV outcome. FDG-PET was nonlocalizing or nonconcordant in seven patients with Engel I, and one with Engel III outcome. The sensitivity, specificity, PPV, and NPV of MEG were 85.0%, 99.1%, 94.4%, and 97.3%, respectively. The sensitivity, specificity, PPV, and NPV of FDG-PET were 65.0%, 94.4%, 68.4%, and 93.6%, respectively. There was no significant difference between MEG and FDG-PET for concordance with surgical resection (χ(2) =2.794, p=0.095). FDG-PET+MEG, defined as two tests concordant with surgical resection, had reduced sensitivity and NPV, but increased specificity and PPV (55.0%, 92.3%, 100%, and 100%, respectively) relative to individual tests. FDG-PET/MEG, defined as one or both test(s) concordant with surgical resection, had increased sensitivity and NPV but reduced specificity (95.0%, 99.0%, and 93.5%, respectively) relative to individual tests. The two tests FDG-PET and MEG were complementary in the assessment of children with localization-related epilepsy, particularly when one test was nonlocalizing or nonconcordant.

Accuracy of FDG-PET–CT in the Diagnostic Work-up of Vascular Prosthetic Graft Infection

SummaryAim: To examine the utility of 2’-[18F]-fluoro-2’-deoxy-D-glucose positron emission tomography (FDG-PET) for detecting multiple primary cancers (MPC) in patients with hypopharyngeal cancer (HPC). Patients, methods: Seventy patients with HPC underwent FDG-PET to determine the staging. Routine clinical examinations were carried out, including computed tomography (CT), magnetic resonance imaging (MRI), ultrasound (US), and oesophagealgastroduodenoscopy (EGDS). The detection rate of synchronous and metachronous cancer was calculated based on FDG-PET alone or FDG-PET combined with clinical routine examination. Sensitivity, specificity, positive predictive values (PPV), negative predictive values (NPV), and accuracy were used to diagnose oesophageal cancer using FDG-PET. Results: Of the 70 patients, 12 (17.1%) had 15 synchronous tumours, and 2 of the 58 remaining patients (3.4%) had metachronous tumours. Oesophageal cancer was discovered most frequently: superficial type (n=6), advanced type (n=4). On a per-patient basis, 11 of 12 patients (91.6%) were diagnosed with synchronous tumours, and on a per-lesion basis, 12 of 15 lesions (80.0%) were detected by FDG-PET.The sensitivity, specificity, accuracy, PPV, and NPV of FDG-PET regarding oesophageal cancer were 70%, 100%, 95.7%, 100%, and 95.2% respectively. Three of the six superficial types were positive on FDG-PET. Both of the metachronous tumour lesions were detected by FDG-PET. Conclusion: FDG-PET is useful for estimating the MPC in HPC patients. Since 3 of 10 synchronous oesophageal cancer were missed with PET alone, a combination with EGDS should be considered to exclude synchronous oesophageal cancer.

The purpose of this study was to investigate the pitfalls of using 2-[18F]-fluoro-2-deoxy-D: -glucose positron emission tomography (FDG-PET) for the evaluation of osteoblastic bone metastases in patients with breast cancer by comparing it with (99m)Tc-hydroxymethylene diphosphonate bone scintigraphy. Among the 89 breast cancer patients (mean age 59+/-15 years) who had undergone both FDG-PET and bone scintigraphy within 1 month between September 2003 and December 2004, 55 with bone metastases were studied. The bone metastases were visually classified by multi-slice CT into four types according to their degree of osteosclerosis and osteolysis-osteoblastic, osteolytic, mixed and invisible-and compared in terms of tracer uptake on FDG-PET or bone scintigraphy and SUV(mean) on FDG-PET. Differences in the rate of detection on bone scintigraphy and FDG-PET were analysed for significance by the McNemar test. The sensitivity, specificity and accuracy of bone scintigraphy were 78.2%, 82.4% and 79.8% respectively, and those of FDG-PET were 80.0%, 88.2% and 83.1%, respectively, revealing no significant differences. According to the CT image type, the visualisation rate of bone scintigraphy/FDG-PET was 100%/55.6% for the blastic type, 70.0%/100.0% for the lytic type, 84.2%/94.7% for the mixed type and 25.0%/87.5% for the invisible type. The visualisation rates of bone scintigraphy for the blastic type and FDG-PET for the invisible type were significantly higher. The SUV(mean) of the blastic, lytic, mixed and invisible types were 1.72+/-0.28, 4.14+/-2.20, 2.97+/-1.98 and 2.25+/-0.80, respectively, showing that the SUV(mean) tended to be higher for the lytic type than for the blastic type. FDG-PET showed a low visualisation rate in respect of osteoblastic bone metastases. Although FDG-PET is useful for detection of bone metastases from breast cancer, it is apparent that it suffers from some limitations in depicting metastases of the osteoblastic type.

To examine the utility of 2'-[18F]-fluoro-2'-deoxy-D-glucose positron emission tomography (FDG-PET) for detecting multiple primary cancers (MPC) in patients with hypopharyngeal cancer (HPC). Seventy patients with HPC underwent FDG-PET to determine the staging. Routine clinical examinations were carried out, including computed tomography (CT), magnetic resonance imaging (MRI), ultrasound (US), and oesophagealgastroduodenoscopy (EGDS). The detection rate of synchronous and metachronous cancer was calculated based on FDG-PET alone or FDG-PET combined with clinical routine examination. Sensitivity, specificity, positive predictive values (PPV), negative predictive values (NPV), and accuracy were used to diagnose oesophageal cancer using FDG-PET. Of the 70 patients, 12 (17.1%) had 15 synchronous tumours, and 2 of the 58 remaining patients (3.4%) had metachronous tumours. Oesophageal cancer was discovered most frequently: superficial type (n=6), advanced type (n=4). On a per-patient basis, 11 of 12 patients (91.6%) were diagnosed with synchronous tumours, and on a per-lesion basis, 12 of 15 lesions (80.0%) were detected by FDG-PET. The sensitivity, specificity, accuracy, PPV, and NPV of FDG-PET regarding oesophageal cancer were 70%, 100%, 95.7%, 100%, and 95.2% respectively. Three of the six superficial types were positive on FDG-PET. Both of the metachronous tumour lesions were detected by FDG-PET. FDG-PET is useful for estimating the MPC in HPC patients. Since 3 of 10 synchronous oesophageal cancer were missed with PET alone, a combination with EGDS should be considered to exclude synchronous oesophageal cancer.

To investigate the diagnostic features of whole-body diffusion-weighted magnetic resonance imaging (DWI) as compared with 2-[(18)F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) and (123)I-meta-iodo-benzyl guanidine scintigraphy (MIBG) on metastatic lesions of patients with malignant pheochromocytoma or paraganglioma. We prospectively studied 11 patients with histologically confirmed pheochromocytoma/paraganglioma and possible metastatic lesions. FDG-PET, MIBG, and DWI examinations were performed within 1 week, and the images were visually interpreted. Abnormal positive uptake either on MIBG or on FDG-PET was considered as metastases. Abnormal high signal intensities on DWI were considered as metastases using conventional T1-and T2-weighted images as reference. FDG-PET and DWI demonstrated metastatic lesions in all 11 patients, but MIBG showed no metastatic lesions in two patients. The numbers of lymph node metastases depicted on FDG-PET, MIBG, and DWI were 19, 6, and 39; bone metastases were 50, 49, and 60; liver metastases were 9, 9, and 15; lung metastases were 5, 7, and 5, respectively. MIBG failed to demonstrate many metastatic lesions, which were demonstrated on FDG-PET or DWI, although two mediastinal lymph node metastases, three lung metastases, and six bone metastases, which were not seen on DWI, were clearly demonstrated on MIBG. DWI showed 15 liver metastases, but 6 of them were not seen on FDG-PET or MIBG. DWI may be particularly advantageous in depicting lymph node and liver metastases and may have a higher rate of detecting metastatic lesions when compared with MIBG or FDG-PET. The limitations of DWI were possible false-positive finding, and probable lower detectability of mediastinal lymph node and lung metastasis.

2-(18F)-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is an imaging technique which enables detection of malignancies. FDG-PET has been established as a tool for the diagnosis of pancreatic carcinoma (CA). Early detection is mandatory as cure can only be achieved in non-advanced disease. This is, however, very difficult with conventional radiological techniques. Patients with chronic pancreatitis (CP) are at risk of developing CA. A simple, reliable screening method for malignant degeneration is highly desirable. We set out to investigate whether FDG-PET is able to detect CA in the setting of CP and can fulfil a potential role in the early detection of CA in CP. FDG-PET was performed in 77 CP patients and in six patients with CP complicated by CA (CP + CA). We included 26 CA patients as a positive control. A positive scan was defined as focal FDG accumulation in the pancreas region. In 67 of the 77 CP (87%) patients, pancreatic FDG accumulation was absent. Six patients had significant accumulation. In CA, 24/26 patients had a positive PET. Five out of the six patients with CP + CA had focal uptake, while minor uptake was seen in one patient. FDG-PET was positive in almost all CA patients and CP + CA patients. FDG-PET was negative in the large majority (87%) of CP patients, which suggests that a positive PET scan in CP patients must lead to efforts to exclude a malignancy. These data suggest that FDG-PET has a potential role as a diagnostic tool for detecting CA in longstanding CP.

Comparison of pseudocontinuous arterial spin labeling perfusion MR images and time-of-flight MR angiography in the detection of periictal hyperperfusion

Whole-body 2-[18F]-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) for accurate staging of Hodgkin’s disease

Familial adenomatous polyposis (FAP) is characterised by colonic and duodenal adenomatous polyps that carry a risk of malignant transformation. Malignant degeneration of duodenal adenomas is difficult to detect. We speculated that 2-((18)F)-fluoro-2-deoxy-D: -glucose positron emission tomography (FDG-PET) might be able to detect early duodenal cancer in FAP. Accordingly, we investigated the role of FDG-PET in the management of FAP patients. FDG-PET was performed in 24 FAP patients. Eight had advanced duodenal adenomas (Spigelman IV), including two patients with duodenal cancer. Scans were defined as positive on the basis of focal FDG accumulation. Pathological FDG accumulation was absent in 19 of 24 patients. All six patients with Spigelman IV duodenal adenomas (without cancer) were negative; two of these underwent a duodenectomy and pathological examination did not reveal duodenal cancer. In five patients, FDG-PET revealed significant uptake, in the duodenum (2), lower abdomen (1), lung (1) and multiple sites in the abdomen (1). These hot spots correlated with duodenal cancer (2), abdominal metastasis (1) and sclerosing haemangioma of the lung (1). We failed to make a histopathological diagnosis in the single patient with multiple intra-abdominal sites of FDG uptake. None of the patients from the FDG-PET-negative group developed cancer during follow-up (mean 2.8 years). FDG-PET detected all the cancers present, and none of the patients with negative FDG-PET developed cancer. This suggests that positive FDG-PET in FAP patients should lead to further examinations to rule out cancer. In patients with negative FDG-PET a more conservative approach seems justified.

18F] 3-deoxy-3′-fluorothymidine positron emission tomography: alternative or diagnostic adjunct to 2-[18f]-fluoro-2-deoxy-d-glucose positron emission tomography in the workup of suspicious central focal lesions?

2-(18F)-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is a noninvasive imaging technique used clinically to detect malignant tumors. FDG-PET has been established as a tool for diagnosis of recurrent or metastatic colorectal carcinoma. Several case series suggest that FDG-PET also detects larger adenomas. The goal of this study was to investigate whether FDG-PET is able to detect colonic adenomas. FDG-PET was performed in 100 consecutive patients in whom colonic adenomas were suspected on barium enema (n = 47) or sigmoidoscopy (n = 53). A positive scan was defined as focal large bowel FDG accumulation. FDG-PET was followed in all cases by colonoscopy, and removed adenomas were examined histopathologically. Colonoscopy confirmed the presence of adenomas in 68 of 100 patients. In 35 patients, there was focal FDG accumulation at site of the adenoma. The sensitivity of FDG-PET increased with adenoma size (21%, adenomas 1 to 5 mm; 47%, 6 to 10 mm; and 72%, > 11 mm). The sensitivity of FDG-PET also increased with the grade of dysplasia (33%, low grade; 76%, high grade; and 89%, carcinomas). The overall specificity was 84%. FDG-PET detects colonic adenomas and the diagnostic test characteristics improve with size and grade of dysplasia of the adenoma.