fluoro-2-deoxy-D-glucose Positron Emission Tomography Scans Research Articles

Relative cerebral flow from dynamic PIB scans as an alternative for FDG scans in Alzheimer's disease PET studies.

In Alzheimer’s Disease (AD) dual-tracer positron emission tomography (PET) studies with 2-[18F]-fluoro-2-deoxy-D-glucose (FDG) and 11C-labelled Pittsburgh Compound B (PIB) are used to assess metabolism and cerebral amyloid-β deposition, respectively. Regional cerebral metabolism and blood flow (rCBF) are closely coupled, both providing an index for neuronal function. The present study compared PIB-derived rCBF, estimated by the ratio of tracer influx in target regions relative to reference region (R1) and early-stage PIB uptake (ePIB), to FDG scans. Fifteen PIB positive (+) patients and fifteen PIB negative (-) subjects underwent both FDG and PIB PET scans to assess the use of R1 and ePIB as a surrogate for FDG. First, subjects were classified based on visual inspection of the PIB PET images. Then, discriminative performance (PIB+ versus PIB-) of rCBF methods were compared to normalized regional FDG uptake. Strong positive correlations were found between analyses, suggesting that PIB-derived rCBF provides information that is closely related to what can be seen on FDG scans. Yet group related differences between method’s distributions were seen as well. Also, a better correlation with FDG was found for R1 than for ePIB. Further studies are needed to validate the use of R1 as an alternative for FDG studies in clinical applications.

Prognostic value of FDG-PET scans at diagnosis in small cell lung cancer

Background: Small cell lung carcinoma (SCLC) is one of the most aggressive solid tumors. The predictive and prognostic role of positron emission tomography (PET) scans in SCLC is under investigation and is yet to be determined. Method: We retrospectively analyzed the correlation between overall survival and 2-[18F]-fluoro-2-deoxy-d-glucose- PET (FDG-PET) results at diagnosis. We also introduced the concept of the total standardized uptake value (SUV) as a possible biomarker for the total burden disease. In addition, we proposed a new staging concept using PET scan based on whether tumor uptake is or is not limited to parenchymal hemithorax. Results: Between March 2004 and February 2009, 46 patients with histologically confirmed SCLC were included in the analysis. Thirty patients were found to have Eastern Cooperative Oncology Group (ECOG) Performance Status ≤ 2, and most (65%, n = 30) of them had limited stage disease using conventional clinical staging criteria. There was a fair correlation between PET results and conventional staging by CT scan (kappa = 0.330). Although there was a trend toward upstaging by PET, it was not predictive of survival. There was a direct correlation between total SUV and maximum SUV and overall survival (hazard ratio [HR] = 1.003 and 1.085, respectively). Conclusion: PET scan results at diagnosis could play an important role in the management of SCLC. Total SUV could represent a good biomarker for the disease burden in SCLC. Further prospective studies are needed to clarify the application of total SUV in SCLC.

The Significance of Alteration 2-[fluorine-18]fluoro-2-deoxy-d-glucose Uptake in the Liver and Skeletal Muscles of Patients with Hyperthyroidism

Hyperthyroidism leads to an enhanced demand for glucose. The hypothesis of the study is that 2-[fluorine-18]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) can demonstrate the alteration of systemic glucose metabolism in hyperthyroidism patients by measuring the FDG standard uptake value (SUV) in liver and skeletal muscle. Forty-eight active hyperthyroidism patients and 30 control participants were recruited for the study. The intensity of FDG uptake in the liver and thigh muscles was graded subjectively, comprising three groups: group I, higher FDG uptake in the liver; group II, equal FDG uptake in the liver and muscles; and group III, higher FDG uptake in the muscles. Ten subjects with FDG PET scans at hyperthyroid and euthyroid status were analyzed. Serum levels of thyroxine (T4) and triiodothyronine (T3) correlated to the SUVs of the liver and muscles. Forty-one patients (41/48, 85.4%) showed symmetrically increased FDG uptake in the muscles (22 in group I, 9 in group II, and 17 in group III). Group I patients were significantly older than group II (P = .02) and group III (P = .001) patients. The correlation coefficient between the serum T3, T4, and SUV levels in the muscles was significant (r = 0.47-0.77, P < .01), particularly in liver and muscle FDG uptake between hyperthyroid and euthyroid states. In the 30 control subjects, there was normal physiological FDG uptake in the liver and muscles. In PET scans showing a pattern of decreased liver and increased skeletal muscle FDG uptake in hyperthyroidism patients, this change of FDG distribution is correspondence to the severity of hyperthyroidism status.

First-in-Human Phase I Trial of Two Schedules of OSI-930, a Novel Multikinase Inhibitor, Incorporating Translational Proof-of-Mechanism Studies

OSI-930 is a novel, potent, oral small-molecule receptor tyrosine kinase inhibitor, predominantly against VEGF receptors (VEGFR), c-Kit, and platelet-derived growth factor receptors. A phase I trial was undertaken to determine safety, maximum-tolerated dose (MTD), pharmacokinetics, pharmacodynamics, and antitumor activity of OSI-930 in patients with advanced solid tumors. OSI-930 was administered once or twice a day using a modified accelerated titration design. Pharmacokinetics and plasma soluble VEGFR2 (sVEGFR2) studies were undertaken. Dynamic contrast-enhanced MRI (DCE-MRI) and 2[18F]fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) MTD expansion cohorts were conducted. Fifty-eight patients received OSI-930 in 2 schedules; once a day schedule: 12 patients at doses up to 1,600 mg without reaching MTD; twice a day schedule: 46 patients at 400 mg (n = 7), 500 mg (n = 31), and 600 mg (n = 8). Dose-limiting toxicities were observed at 600 mg twice a day (n = 3): G3 rash (n = 2) and G4 γ-glutamyltransferase, establishing the MTD at 500 mg twice a day. Common G1-2 toxicities included fatigue, diarrhea, nausea, and rash. Antitumor responses were seen in 2 patients with advanced ovarian cancer [Response Evaluation Criteria in Solid Tumors (RECIST) partial response (PR) (n = 1); GCIG CA125 response (n = 1)]. Eleven of 19 heavily pretreated imatinib-resistant patients with gastrointestinal stromal tumors achieved RECIST stable disease (median duration: 126 days), with FDG-PET scans showing PRs in 4 of 9 patients. OSI-930 exposure increased with dose; substantial decreases in sVEGFR levels were observed with OSI-930 twice a day doses ≥400 mg, while DCE-MRI responses were shown in 4 of 6 patients. OSI-930 is safe and well tolerated, with pharmacokinetic-pharmacodynamic data supporting proof-of-mechanism with clinically relevant antitumor activity.

The Frequency and Spectrum of Thymus 2-[Fluorine-18] Fluoro-2-deoxy-D-glucose Uptake Patterns in Hyperthyroidism Patients

Thymic hyperplasia is associated with hyperthyroidism. Increased thymus 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) uptake in hyperthyroidism patients has been reported. The aim of this study was to analyze the FDG positron emission tomography (PET) thymus uptake spectrum in patients with active hyperthyroidism with correlation with serum hormones. The prospective study included FDG PET scans from 65 hyperthyroidism patients and 30 subjects with euthyroid status as control group. The intensity of FDG uptake in thyroid and thymus regions was graded subjectively on a five-point scale and semi-quantitatively by measuring standard uptake value (SUV). Correlation coefficient between thymus SUV and serum thyroxine, triiodothyronine, thyrotropin, thyroid peroxidase antibodies (TPO Ab), thyrotropin receptor autoantibody (TR Ab), and thymulin were analyzed. Among 65 hyperthyroidism patients, 30 (46.2%) and 39 (60%) patients showed thyroid and thymus FDG uptake, respectively. The frequency of thymus uptake FDG was high in patients younger than age 40 (28/31, 90.3%). The patterns of the thymic FDG uptake include inverted V or triangular, separated triangular, united nontriangular, unilateral right or left extension, and focal midline. Focal midline FDG uptake was the most common pattern (15/39, 38.5%). None of the control group showed thymus FDG uptake. The correlation coefficient between the FDG uptake SUV levels in thymus and serum hormones, thyrotropin, TPO Ab, TR Ab, and thymulin levels were all low (P > .05). In FDG PET scan, thymus activity was common in hyperthyroidism patients; this should not be misdiagnosed as a malignancy in patients exhibiting weight loss.

Consistency of FDG-PET Accuracy and Cost-Effectiveness in Initial Staging of Patients With Hodgkin Lymphoma Across Jurisdictions

Two hundred ten patients with newly diagnosed Hodgkin's lymphoma (HL) were consecutively enrolled in this prospective trial to evaluate the cost-effectiveness of fluorine-18 ((18)F)-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) scan in initial staging of patients with HL. All 210 patients were staged with conventional clinical staging (CCS) methods, including computed tomography (CT), bone marrow biopsy (BMB), and laboratory tests. Patients were also submitted to metabolic staging (MS) with whole-body FDG-PET scan before the beginning of treatment. A standard of reference for staging was determined with all staging procedures, histologic examination, and follow-up examinations. The accuracy of the CCS was compared with the MS. Local unit costs of procedures and tests were evaluated. Incremental cost-effectiveness ratio (ICER) was calculated for both strategies. In the 210 patients with HL, the sensitivity for initial staging of FDG-PET was higher than that of CT and BMB in initial staging (97.9% vs. 87.3%; P < .001 and 94.2% vs. 71.4%, P < 0.003, respectively). The incorporation of FDG-PET in the staging procedure upstaged disease in 50 (24%) patients and downstaged disease in 17 (8%) patients. Changes in treatment would be seen in 32 (15%) patients. Cumulative cost for staging procedures was $3751/patient for CCS compared to $5081 for CCS + PET and $4588 for PET/CT. The ICER of PET/CT strategy was $16,215 per patient with modified treatment. PET/CT costs at the beginning and end of treatment would increase total costs of HL staging and first-line treatment by only 2%. FDG-PET is more accurate than CT and BMB in HL staging. Given observed probabilities, FDG-PET is highly cost-effective in the public health care program in Brazil.

Pilot study to evaluate the effect of erlotinib (E) administered before surgery in operable patients with squamous cell carcinoma of the head and neck (SCCHN).

5568 Background: Strategies for early detection of cellular response to EGFR inhibitors are critical to personalizing therapy for SCCHN. The glycolytic enzymes responsible for uptake of the positron emission tomography (PET) tracer [18F] 2- fluoro-2-deoxy-d-glucose (FDG) are regulated by intermediates of the EGFR pathway such as AKT, mTOR and MAPK. It was hypothesized that the inhibition of these EGFR pathway markers could be read by the 18[F]-FDG uptake by tumor. It is also possible that the EGFR pathway is aberrantly activated in some cancers and that glycolysis and downstream effects are not always linked. Previous in vitro and in vivo studies showed that 18[F]-FDG uptake changes very early in SCCHN tumor models responsive to EGFR inhibition. We developed a pilot clinical protocol to investigate this further in patients with SCCHN. Methods: Patients with operable SCCHN with a window of at least 15 days between the time of initial biopsy and established surgery will receive E 150 mg/day or 300 mg/day if the patient is actively smoking. Smokers metabolize E rapidly with an MTD that is twice that of non-smokers. Patients must have additional biopsy tissue for laboratory research studies. 18[F]-FDG PET scan and neck CT with contrast are performed before treatment, 4-6 days through treatment and at the end of E administration. Results: 11 patients have been treated to date with an average of 18.6 days of treatment. Of the 10 evaluable patients, 7 showed partial response (PR) and 3 patients showed stable disease (SD). 8 patients received E 300 mg. No grade 3 or 4 toxicities. Early (4-6 days)18[F]-FDG PET scans showed a decrease in SUV max to 93.25% +/- 18% in patients with SD and to 51% +/- 22% in patients with PR (defined as at least 20% reduction in maximum diameter). This pilot trial will continue to enroll patients to address the primary laboratory research correlative aim. Pre-and post-treatment tumor tissue is available in all patients. Conclusions: Short course treatment with E in a dose adjusted per smoking status is very active in previously untreated patients with SCCHN. Early changes in the 18[F]-FDG PET scan uptake can be used as a marker predictive of response to EGFR inhibition.

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

Objectives To investigate the diagnostic accuracy of fluoro-2-deoxy- d-glucose positron emission tomography (FDG-PET) compared with computed tomography (CT) scanning and added value of fused FDG-PET–CT in diagnosing vascular prosthetic graft infection. Design Prospective cohort study with retrospective analysis. Materials Twenty five patients with clinically suspected vascular prosthetic infection underwent CT and FDG-PET scanning. Methods Two nuclear medicine physicians assessed the FDG-PET scans; all CT scans were assessed by two radiologists. Fused FDG-PET/CT were judged by the radiologist and the nuclear medicine physician. The concordance between CT and FDG-PET and the inter-observer agreement between the different readers were investigated. Results Fifteen patients had a proven infection by culture. Single FDG-PET had the best results (sensitivity 93%, specificity 70%, positive predictive value 82% and negative predictive value 88%). For CT, these values were 56%, 57%, 60% and 58%, respectively. Fused CT and FDG-PET imaging also showed high sensitivity and specificity rates and high positive and negative values. Inter-observer agreement for FDG-PET analysis was excellent (kappa = 1.00) and moderate for CT and fused FDG-PET–CT analysis (0.63 and 0.66, respectively). Conclusion FDG-PET scanning showed a better diagnostic accuracy than CT for the detection of vascular prosthetic infection. This study suggests that FDG-PET provides a useful tool in the work-up for diagnosis of vascular prosthetic graft infection.

La tomographie par émission de positons au 2-[18F]fluoro-2-désoxy- d-glucose (TEP-FDG) permet d’identifier les stades A et B des leucémies lymphoïdes chroniques (LLC)

Purpose There is no data in the literature concerning the utility of 2-[18F]fluoro-2-deoxy- d-glucose positron emission tomography (FDG-PET) in chronic lymphocytic leukaemia (CLL), except for the diagnosis of Richter's transformations. The purpose of this study was to assess the potential role of FDG-PET in CLL stages A and B. Materials and methods Thirty-five patients (61 ± 9 years; 11 women, 24 men; 8B and 27A) have benefited of a FDG-PET scan at baseline, for example, before an eventual treatment. FDG-PET scans were analyzed visually and the maximum values of the Standardised Uptake Value (SUV max) were measured in the main lymph nodes areas. The ability of FDG-PET to differentiate stages A and B patients was evaluated by Student's tests and Receiver Operating Characteristics (ROC) analysis. Results All patients with a normal FDG-PET ( n = 18) were stages A. The remaining 17 patients (9A and 8B) showed hypermetabolisms in nodal areas above ( n = 17) and below ( n = 9) the diaphragm, and no visceral involvement. The lymph nodes hypermetabolisms were always bilateral, and of low intensity (≤ mediastinum; 9A), or of higher intensity (≥ liver, 8B). The SUV max of stage B ( n = 8) were significantly higher than those of the 27 stages A, in all lymph nodes areas except in mediastinum. The highest intensity of FDG uptake was observed in axillary area in stages B patients (SUV max = 2.74 ± 1.03). An axillary SUV max of 1.33 is the most suitable value for the discrimination between stages A and B patients (ROC; AUC = 0.968; sensitivity 1.00; specificity 0.91). Conclusion Lymph nodes hypermetabolisms are constant in the B stage, and more intense than in stage A. These anomalies are always bilateral, unlike what is observed in Richter's transformation. The intensity of axillary lymph nodes FDG uptake can distinguish CLL stages A and B.

Influence of mild hyperglycemia on cerebral FDG distribution patterns calculated by statistical parametric mapping

In clinical cerebral 2-[(18)F]fluoro-2-deoxy-D: -glucose positron emission tomography (FDG-PET) studies, we sometimes encounter hyperglycemic patients with diabetes mellitus or patients who have not adhered to the fasting requirement. The objective of this study was to investigate the influence of mild hyperglycemia (plasma glucose range 110-160 mg/dl) on the cerebral FDG distribution patterns calculated by statistical parametric mapping (SPM). We studied 19 healthy subjects (mean age 66.2 years). First, all the subjects underwent FDG-PET scans in the fasting condition. Then, 9 of the 19 subjects (mean age 64.3 years) underwent the second FDG-PET scans in the mild hyperglycemic condition. The alterations in the FDG-PET scans were investigated using SPM-and region of interest (ROI)-based analyses. We used three reference regions: (1) SPM global brain (SPMgb) used for SPM global mean calculation, (2) the gray and white matter region computed from magnetic resonance image (MRIgw), and (3) the cerebellar cortex (Cbll). The FDG uptake calculated as the standardized uptake value (average) in SPMgb, MRIgw, and Cbll regions in the mild hyperglycemic condition was 42.7%, 41.3%, and 40.0%, respectively, of that observed in the fasting condition. In SPM analysis, the mild hyperglycemia was found to affect the cerebral distribution patterns of FDG. The FDG uptake was relatively decreased in the gray matter, mainly in the frontal, temporal, and parietal association cortices, posterior cingulate, and precuneus in both SPMgb-and MRIgw-reference-based analyses. When Cbll was adopted as the reference region, those decrease patterns disappeared. The FDG uptake was relatively increased in the white matter, mainly in the centrum semiovale in all the reference-based analyses. It is noteworthy that the FDG distribution patterns were altered under mild hyperglycemia in SPM analysis. The decreased uptake patterns in SPMgb-(SPM default) and MRIgw-reference-based analyses resembled those observed in Alzheimer's disease. Under mild hyperglycemia, we can recommend Cbll as the reference region to detect decreased uptake patterns. We should pay special attention to controlling the diet condition, monitoring hyperglycemia, and optimizing the reference region in SPM analysis, particularly in the diagnosis of early Alzheimer's disease in clinical FDG-PET.

False-positive FDG-PET scan secondary to lipoid pneumonia mimicking a solid pulmonary nodule

Fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) scanning is useful in evaluating suspicious lesions of the lung. Our patient was a 65-year-old woman with a 45-pack-year smoking history who was referred for further evaluation because of a 3 cm x 3 cm solid lung nodule on computed tomography scan of the chest. FDG-PET scan revealed a standard uptake value of 3.2 suggestive of malignancy. The histology of the lung nodule was consistent with lipoid pneumonia, a benign condition frequently associated with inadvertent aspiration or inhalation of oily substances.

Imaging Medullary Thyroid Carcinoma with Persistent Elevated Calcitonin Levels

Because calcitonin level remains elevated after initial treatment in many medullary thyroid carcinoma (MTC) patients without evidence of disease in the usual imaging work-up, there is a need to define optimal imaging procedures. Fifty-five consecutive elevated calcitonin level MTC patients were enrolled to undergo neck and abdomen ultrasonography (US); neck, chest, and abdomen spiral computed tomography (CT); liver and whole-body magnetic resonance imaging (MRI); bone scintigraphy; and 2-[fluorine-18]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET)/CT scan (PET). Fifty patients underwent neck US, CT, and PET, and neck recurrence was demonstrated in 56, 42, and 32%, respectively. Lung and mediastinum lymph node metastases in the 55 patients were demonstrated in 35 and 31% by CT and in 15 and 20% by PET. Liver imaging with MRI, CT, US, and PET in 41 patients showed liver in 49, 44, 41, and 27% patients, respectively. Bone metastases in 55 patients were demonstrated in 35% by PET, 40% by bone scintigraphy, and 40% by MRI; bone scintigraphy was complementary with MRI for axial lesions but superior for the detection of peripheral lesions. Ten patients had no imaged tumor site despite elevated calcitonin level (median 196 pg/ml; range 39-816). FDG uptake in neoplastic foci was higher in progressive patients but with a considerable overlap with stable ones. The most efficient imaging work-up for depicting MTC tumor sites would consist of a neck US, chest CT, liver MRI, bone scintigraphy, and axial skeleton MRI. FDG PET scan appeared to be less sensitive and of low prognostic value.

Early Interim 2-[18F]Fluoro-2-Deoxy-D-Glucose Positron Emission Tomography Is Prognostically Superior to International Prognostic Score in Advanced-Stage Hodgkin's Lymphoma: A Report From a Joint Italian-Danish Study

Starting from November 2001, 260 newly diagnosed patients with Hodgkin's lymphoma (HL) were consecutively enrolled in parallel Italian and Danish prospective trials to evaluate the prognostic role of an early interim 2-[(18)F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) scan and the International Prognostic Score (IPS) in advanced HL, treated with conventional ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) therapy. Most patients (n = 190) presented with advanced disease (stages IIB through IVB), whereas 70 presented in stage IIA with adverse prognostic factors. All but 11 patients were treated with standard ABVD therapy followed by consolidation radiotherapy in case of bulky presentation or residual tumor mass. Conventional radiologic staging was performed at baseline. FDG-PET scan was performed at baseline and after two courses of ABVD (PET-2). No treatment change was allowed on the basis of the PET-2 results. After a median follow-up of 2.19 years (range, 0.32 to 5.18 years), 205 patients were in continued complete remission and two patients were in partial remission. Forty-three patients progressed during therapy or immediately after, whereas 10 patients relapsed. The 2-year progression-free survival for patients with positive PET-2 results was 12.8% and for patients with negative PET-2 results was 95.0% (P < .0001). In univariate analysis, the treatment outcome was significantly associated with PET-2 (P < .0001), stage IV (P < .0001), WBC more than 15,000 (P < .0001), lymphopenia (P < .001), IPS as a continuous variable (P < .0001), extranodal involvement (P < .0001), and bulky disease (P = .012). In multivariate analyses, only PET-2 turned out to be significant (P < .0001). PET-2 overshadows the prognostic value of IPS and emerges as the single most important tool for planning of risk-adapted treatment in advanced HL.

Abdominal positron-emission tomography lesions with increased standardized uptake values correlate with intraoperative findings

Background The reporting of standardized uptake value (SUV) on fluoro-2-deoxy-D-glucose positron-emission tomography (FDG-PET) in colorectal cancer is becoming common practice, but its clinical utility remains to be determined. This study was designed to compare FDG-PET uptake as measured by SUV with operative findings. Methods A colorectal cancer database was queried to identify patients who underwent FDG-PET scans with reported SUVs followed by exploratory laparotomy within 3 months and compare these results to determine FDG-PET sensitivity. Results Of 46 patients, 16 (34.8%) were found to be have increased extent of disease intraoperatively than seen on FDG-PET scan. This patient population had a statistically significant decreased mean maximal SUV than the patients whose FDG-PET scan equaled intraoperative findings ( P < .025). Conclusions This initial study indicates patients with potentially resectable disease by PET scan but decreased FDG uptake should undergo laparoscopic evaluation before performing laparotomy.

頭頸部癌の診断にＦＤＧ‐ＰＥＴが有用であった４例

FDG-PET (2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography) is clinically useful in detecting head and neck cancer providing accurate estimate of primary cancer and metastasis lymph node especially in cancers that are equivocal on conventional imaging. FDG-PET scan shows unknown primary cancer and metastatic lymph nodes that appear normal CT scan/or MRI. Furthmore, whole body FDG-PET makes it possible to simultaneously detect distant metastasis.We reported 4 cases of head and neck cancer and showed the efficacy of 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in the diagnosis of head and neck cancer. FDG-PET is highly useful for detecting previously unrecognized primary cancer with lymph node metastasis to the neck. FDG-PET also has a high potential for detecting neck lymph node metastasis, staging head and neck cancer and assessing its response to irradiation and chemotherapy. Finally, FDG-PET is useful for diagnosing recurrent or residual head and neck cancer and its distant metastasis.

Mucoepidermal carcinoma of the lung detected by positron emission tomography in a 5-year-old girl

The authors describe a rare case of mucoepidermal carcinoma of the lung incidentally identified in preoperative assessments for inguinal hernia repair in a 5-year-old girl. This patient was referred for right external inguinal hernia, and a 3.0-cm round-shaped lesion was found in the right lower lung field of a chest x-ray film. She had no respiratory tract complaints, but her serum carcinoembryonic antigen concentration was markedly elevated (21.2 ng/mL). Chest and abdominal computed tomography/magnetic resonance images could not determine the nature of the lesion, but 2-[ 18F]fluoro-2-deoxy- d-glucose positron emission tomography (FDG-PET) indicated a malignant tumor pattern. The patient underwent a computed tomography–guided needle biopsy of the lesion (S8), which was soon followed by a right lower pulmonary lobectomy. Histopathology of the resected specimen showed mucoepidermal carcinoma with no regional lymph node metastasis. In childhood asymptomatic pulmonary lesions, it is often difficult to rule out the possibility of malignancy. In the present case, FDG-PET scanning appropriately indicated the therapeutic priority of pediatric thoracic surgery.

FDG-PET scanning in the diagnosis of gastrointestinal cancers

This review deals with the current, well-established indications for two-([Formula: See Text]F)-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) scanning in patients with gastrointestinal cancers. FDG-PET is a non-invasive, functional imaging technique. FDG exploits the native glucose transporter to enter the cell. Since many tumours have enhanced glucose uptake, FDG is readily accumulated in malignant cells and can be detected by a PET camera. FDG-PET has been established as an important diagnostic tool in clinical oncology. This review deals with the current, well-established indications for FDG-PET scanning in patients with gastrointestinal cancers. In the current practice, FDG-PET is most commonly used to stage oesophageal carcinoma, to detect and stage recurrence of colorectal carcinoma and to differentiate between benign and malignant pancreatic lesions. The benefit of FDG-PET scanning in patients with oesophagus carcinoma is best established in stage IV disease, as the diagnostic accuracy to detect metastatic disease is higher compared to the combination of computed tomography (CT) and endoscopic ultrasound (EUS). In patients with a history of colorectal carcinoma, FDG-PET scanning is particularly effective in diagnosing recurrent disease, especially in those with a rising carcinoembryonic antigen without a suspect lesion on conventional imaging. Large series have indicated that the sensitivity and specificity for detecting recurrent colorectal carcinoma are in the range of 87%-100% and 66%-100%, respectively. Equally, FDG-PET has a high sensitivity (68%-96%) and specificity (78%-100%) in detecting pancreatic carcinoma in patients with a suspicious-looking pancreatic mass on CT scan. Lastly, we focus on the use of FDG-PET as a modality for early monitoring of treatment response in patients with gastrointestinal stromal cell tumours. Without doubt, future developments will further establish the diagnostic role of the FDG-PET scan in the care of patients with gastrointestinal cancers.

Use of Serial FDG PET to Measure the Response of Bone-Dominant Breast Cancer to Therapy

Rationale and Objectives The authors performed this study to determine the feasibility of using quantitative 2-[fluorine-18]fluoro-2-deoxy- d-glucose (FDG) positron emission tomography (PET) to monitor the response of breast cancer bone metastases to therapy. Materials and Methods Twenty-four women with stage IV bone-dominant breast carcinoma were included in this study. Whole-body FDG PET imaging was performed at serial time points during the course of therapy. FDG PET scans were interpreted quantitatively by using the maximum standard uptake value (SUV) of the most conspicuous bone lesion at baseline FDG PET. PET results were compared to the overall assessment of response (response, stable disease, progressive disease) with a combination of conventional imaging, change in tumor marker values, and subjective symptom changes by experienced medical oncologists blinded to the findings at FDG PET. Changes in FDG SUV were also correlated quantitatively to the changes in a particular tumor marker (CA 27.29). Results The changes in FDG SUV with therapy showed correlation with the overall clinical assessment of response ( P < .01). The percentage change in FDG uptake with therapy showed strong correlation with the percentage change in tumor marker value ( P < .01). Conclusion Preliminary results indicate that serial whole-body FDG PET can help quantitatively assess the response of breast cancer bone metastases to therapy. Prospective trials are needed to further investigate its accuracy.

Preoperative diagnostic value of [(18)F] fluorodeoxyglucose positron emission tomography in patients with radioiodine-negative recurrent well-differentiated thyroid carcinoma.

To assess the utility of 2-[(18)F] fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) to detect recurrent disease in the follow-up of patients with well-differentiated thyroid cancer (WDTC) who have negative diagnostic (131)I scans and abnormal thyroglobulin levels. In general, patients with WDTC have an excellent long-term prognosis when appropriate surgical treatment and follow-up are carried out. After total thyroid ablation, whole-body (131)I scintigraphy and measurement of serum thyroglobulin are useful diagnostic tools to detect persistent or recurrent malignancy. In case of tumor dedifferentiation, decreased or lost iodine-accumulating ability may lead to false-negative (131)I scanning results. The diagnostic and therapeutic delay is responsible for a poor prognosis in this subgroup of patients. Efforts have been made in the search for suitable imaging modalities capable of early detection of recurrent thyroid carcinoma. The authors prospectively analyzed 24 patients with WDTC, negative results of whole-body (131)I scintigraphy, and elevated serum thyroglobulin concentrations. Attenuation-corrected whole-body FDG-PET scans from the neck to the upper legs were performed. In addition, all patients underwent cervical ultrasonography. The results of the imaging studies were compared with histopathologic findings. If no resection of the suspicious lesion was carried out, computed tomography data were used as control criteria. Overall, FDG-PET disclosed 38 hot spots. The sensitivity of the method was 94.6%, but the specificity was lower (25.0%). The diagnostic accuracy was 87.8%. There were three false-positive results in two patients with benign cervical lymph nodes. In one patient with regional lymph node metastases in the neck, two false-negative results were obtained. Ultrasound classified both findings as malignant, however. Because of unexpected findings, FDG-PET suggested potential modification of the surgical management in nine patients. Distant metastases could be disclosed using FDG-PET in only three patients. FDG-PET is a useful diagnostic tool in the follow-up of thyroidectomized patients with WDTC, negative (131)I scanning results, and abnormal serum thyroglobulin concentrations. The method detects metastatic disease in 94.6% of cases. PET results changed surgical tactics in a significant number of patients. Accurate staging of locoregional cancer recurrence in the neck may be consummately obtained by concomitant analysis of PET and ultrasound results.

Can positron emission tomography improve the quality of care for head-and-neck cancer patients?

Purpose: Fluoro-2-deoxy-d-glucose-positron emission tomography (FDG-PET) is a functional imaging modality that measures the relative uptake of 18FDG with PET. The purpose of this review is to assess the potential contribution of FDG-PET scans to the treatment of head-and-neck cancer patients. Methods and Materials: Data were assessed from the literature with attention to what additional information may be gained from the use of FDG-PET in four clinical settings: ( 1) detection of occult metastatic disease in the neck, ( 2) detection of occult primaries in patients with neck metastases, ( 3) detection of synchronous primaries or metastatic disease in the chest, and ( 4) detection of residual/recurrent locoregional disease. Results: Although the data are somewhat conflicting, FDG-PET appears to add little additional value to the physical examination and conventional imaging studies (supplemented by biopsy when appropriate) for the detection of subclinical nodal metastases, unknown primaries, or disease in the chest. However, FDG-PET scans are quite useful in differentiating residual/recurrent disease from treatment-induced normal tissue changes. A positive FDG-PET scan at 1 month after radiotherapy is highly indicative of the presence of residual disease, and a negative scan at 4 months after treatment is highly predictive of tumor eradication. Conclusions: Large-scale studies using newer generation equipment and more defined methods are needed to more rigorously assess the potential of FDG-PET in the detection of subclinical primary or simultaneous secondary tumors and of nodal or systemic spread. Currently, however, FDG-PET can contribute to the detection of residual/early recurrent tumors, leading to the timely institution of salvage therapy or the prevention of unnecessary biopsies of irradiated tissues, which may aggravate injury.