Biomedical subjects

S N Reske

Publications and source records attributed to S N Reske.

At least 55 records · Page 3Linked to original sources

PubMed2000

Primary staging of lymphomas: cost-effectiveness of FDG-PET versus computed tomography.

The objective of this study was to measure the incremental cost-effectiveness of 2-(fluorine-18) fluorodeoxyglucose positron emission tomography (FDG-PET) versus computed tomography (CT) as diagnostic procedures in the primary staging of malignant lymphomas. The study was based on 22 patients of a clinical study who underwent the diagnostic procedures at Ulm University Hospital between April 1997 and May 1998. Direct costs of FDG-PET and CT, including staff, materials, investment, maintenance and overheads, were valued using a micro-costing approach. The effectiveness of both diagnostic procedures was measured as the percentage of correctly staged patients, given a gold standard for staging. The incremental cost-effectiveness ratio was the main outcome measure. Costs per patient of FDG-PET were 257 euros for FDG production and 704 euros for the FGD-PET scan, thus totalling 961 euros (in 1999 prices). The cost per patient of CT scans was found to be 391 euros. Verified PET findings induced an upstaging in four patients such that the effectiveness was 81.8% (18/22) for CT and 100% (22/22) for PET. Incremental cost-effectiveness ratios (interpreted as the additional costs of a more effective diagnostic strategy per additional unit of effectiveness, i.e. additionally correctly staged patient, achieved) were 478 euros per correctly staged patient for CT versus "no diagnostics" and 3133 euros for FDG-PET versus CT. Great potential for cost saving was identified in sensitivity analyses for FDG-PET. It is concluded that diagnostic accuracy and the costs of the diagnostic procedures could be measured precisely. FDG-PET was more accurate than CT. Decision-makers who consider savings in treatment costs significant may find the cost-effectiveness ratio of PET to lie within an acceptable range. However, more research is needed to assess the long-term treatment and cost effects of more accurate staging. There is significant potential to improve the technical efficiency of PET.

Adolescent↗

PubMed2000

Is (18)F-fluorodeoxyglucose positron emission tomography in recurrent colorectal cancer a contribution to surgical decision making?

BACKGROUND: Accuracy of (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) and contribution to surgical decision making in recurrent or metastatic colorectal cancer were evaluated. METHODS: One hundred whole-body PET tests in colorectal cancer patients (1994 to 1998) were compared with computed tomography (CT), liver ultrasonography, and carcinoembryonic antigen (CEA) test. Mean follow-up was 12 months. RESULTS: Sensitivity, specificity, and accuracy of FDG-PET for malignant findings were, respectively, 98%, 90% and 95%; for 87 CT scans, 91%, 72%, and 82%; for 98 CEA tests, 76%, 90%, and 82%; for detection of liver metastases with PET, 100%, 99%, and 99%; and for 68 ultrasound tests, 87%, 96%, and 93%. PET accuracy for local recurrence was 96%. Additional information was provided by PET in 86% of cases (abdomen, thorax, liver). PET influenced surgical decisions in 61% of cases. CONCLUSION: FDG-PET adds relevant accuracy to the conventional staging of patients with colorectal cancer and may cost-effectively help to select the appropriate treatment.

Abdominal Neoplasms↗

PubMed2000

CD34+ selected cells in mismatched stem cell transplantation: a single centre experience of haploidentical peripheral blood stem cell transplantation.

Over the past 3 years we have performed 10 haploidentical peripheral blood stem cell transplants in patients with incurable haematological malignancies and no prospect of a matched unrelated donor within an adequate time period. Conditioning consisted of ATG, TBI, thiotepa, cyclophosphamide and additional radioimmunotherapy in five patients. All patients received G-CSF mobilized peripheral blood stem cell grafts. GVHD prophylaxis consisted of T cell depletion by CD34+ selection; no post-transplant immunosuppression was given in nine patients. Stable engraftment was achieved in nine patients; one case of acute graft rejection was observed. Seven patients developed grade I acute GVHD, and six patients have developed chronic GVHD. Infections were the most significant clinical problem post transplant. Two patients have suffered a relapse of their disease and two further patients have died of transplant-related complications. After a median follow-up of 13 months (range 5-37 months) six patients are surviving in remission. We conclude that haploidentical PBSCT is a reasonable alternative to a MUD transplant.

Adult↗

PubMed2000

Values and limitations of 18F-fluorodeoxyglucose-positron-emission tomography with preoperative evaluation of patients with pancreatic masses.

The aim of this study was to determine the value and limitations of 18F-fluorodeoxyglucose (FDG)-position-emission tomography (PET) for differentiating benign and malignant pancreatic disease and for staging malignant disease. One hundred fifty-nine patients with 89 malignant and 70 benign pancreatic lesions all received PET, computed tomography (CT), and endoscopic retrograde cholangiopancreatography (ERCP) before pancreatic surgery. The original reports were compared for all patients (group I; N = 159), for a subgroup that neither had fasting plasma glucose levels > or =130 mg/dL or known elevated levels of C-reactive protein ([CRP], group II; n = 123), and for the remaining patients (group III; n = 36). For group I, accuracy values (areas under receiver operating characteristic [ROC] curves) for differentiation of benign/malignant masses were 0.86 (PET), 0.93 (ERCP), 0.82 (CT), and 0.95 for ERCP + PET (N = 159). For group II, ROC areas increased to 0.92 (PET), 0.94 (p < 0.05; n = 123) (ERCP), 0.82 (CT), 0.97 (p < 0.05; n = 123) (ERCP + PET). The results for group III were 0.71 (PET), 0.81 (CT), and 0.93 (ERCP); (n = 36). With 54 patients of group II that either had contradictory or indeterminate/technically unsuccessful CT/ERCP, PET was correct in 43 patients (84%). Sensitivity/specificity for lymph node staging was 49%/63%, respectively. For patients with hepatic metastasis, PET was 70% sensitive and 95% specific, missing some metastasis that were <1 cm. PET detected peritoneal metastasis in 25% of patients, missing poorly localized microscopic spread. For selected patients who have indeterminate pancreatic masses but no hyperglycemia or serologic evidence of active inflammation, FDG-PET is an independent functional assay that significantly adds to the diagnostic accuracy of ERCP and CT in the differentiation of benign and malignant pancreatic disease. PET can reliably detect hepatic, peritoneal, and other distant metastases that are > or =1 cm.

Area Under Curve↗

PubMed2000

Simultaneous iterative reconstruction for emission and attenuation images in positron emission tomography.

The quality of the attenuation correction strongly influences the outcome of the reconstructed emission scan in positron emission tomography. Usually the attenuation correction factors are calculated from the transmission and blank scan and thereafter applied during the reconstruction on the emission data. However, this is not an optimal treatment of the available data, because the emission data themselves contain additional information about attenuation: The optimal treatment must use this information for the determination of the attenuation correction factors. Therefore, our purpose is to investigate a simultaneous emission and attenuation image reconstruction using a maximum likelihood estimator, which takes the attenuation information in the emission data into account. The total maximum likelihood function for emission and transmission is used to derive a one-dimensional Newton-like algorithm for the calculation of the emission and attenuation image. Log-likelihood convergence, mean differences, and the mean of squared differences for the emission image and the attenuation correction factors of a mathematical thorax phantom were determined and compared. As a result we obtain images improved with respect to log likelihood in all cases and with respect to our figures of merit in most cases. We conclude that the simultaneous reconstruction can improve the performance of image reconstruction.

Algorithms↗

PubMed2000

Radioimmunotherapy for the intensification of conditioning before stem cell transplantation: differences in dosimetry and biokinetics of 188Re- and 99mTc-labeled anti-NCA-95 MAbs.

UNLABELLED: A new concept is the intensification of preparative regimens for patients with advanced leukemia using monoclonal antibodies (MAbs) with an affinity for beta emitter-labeled bone marrow. 188Re is a high-energy beta emitter that has therapeutic promise. Our first aim was to clarify whether the therapeutic application of 188Re-MAb against nonspecific cross-reacting antigen 95 (NCA-95) can be predicted from biokinetic data derived from 99mTc-labeled NCA-95. Our second aim was to show that a radiation absorbed dose of > or =12 Gy in the bone marrow can be achieved using 188Re-MAb. METHODS: Dosimetric data were obtained for both radiotracers from multiple planar whole-body scans (double-head gamma camera), blood samples, and urine measurements from 12 patients with advanced leukemia. Radiation absorbed doses were calculated using MIRDOSE 3 software. RESULTS: Radiation absorbed doses to bone marrow, liver, spleen, lung, and kidney were 2.24, 0.50, 1.93, 0.05, and 0.90 mGy/MBq, respectively, using 99mTc-MAb and 1.45, 0.43, 1.32, 0.07, and 0.71 mGy/MBq, respectively, using 188Re-MAb. These differences were statistically significant for bone marrow, spleen, and kidney. The main differences were less accumulation of 188Re-MAb in bone marrow (31%+/-13% compared with 52%+/-13%) and faster elimination through urine (25%+/-3% compared with 15%+/-5% after 24 h). On the basis of these data, a mean marrow dose of 14+/-7 Gy was achieved in 12 patients suffering from leukemia after application of approximately 10+/-2 GBq 188Re-MAb. CONCLUSION: Myeloablative radiation absorbed doses can easily be achieved using 188Re-MAb. 99mTc- and 188Re-MAb showed similar whole-body distributions. However, direct prediction of radiation absorbed doses from the 99mTc-MAb, assuming identical biokinetic behavior, is not valid for the 188Re-MAb in a single patient. Therefore, individual dosimetry using 188Re-MAb is needed to calculate therapeutic activity.

Adult↗

PubMed2000

Grading of tumors and tumorlike lesions of bone: evaluation by FDG PET.

UNLABELLED: Clinical diagnosis of skeletal tumors can be difficult, because such lesions compose a large, heterogeneous group of entities with different biologic behaviors. The aim of this prospective study was to assess the value of PET in grading tumors and tumorlike lesions of bone. METHODS: Two hundred two patients with suspected primary bone tumors were investigated using FDG PET. Uptake of FDG was evaluated semiquantitatively by determining the tumor-to-background ratio (T/B). All patients underwent biopsy, resulting in the histologic detection of 70 high-grade sarcomas, 21 low-grade sarcomas, 40 benign tumors, 47 tumorlike lesions, 6 osseous lymphomas, 6 plasmacytomas, and 12 metastases of an unknown primary tumor. RESULTS: All lesions, with the exception of 3 benign tumors, were detected by increased FDG uptake. Although sarcomas showed significantly higher T/Bs than did latent or active benign lesions (P < 0.001), aggressive benign lesions could not be distinguished from sarcomas. Using a T/B cutoff level for malignancy of 3.0, the sensitivity of FDG PET was 93.0%, the specificity was 66.7%, and the accuracy was 81.7%. CONCLUSION: FDG PET provides a promising tool for estimating the biologic activity of skeletal lesions, implicating consequences for the choice of surgical strategy.

Adult↗

PubMed1999

[Current status of positron emission tomography in diagnosis of abdominal tumors].

PET is recognized as a powerful imaging research tool. Based on pathophysiological and biochemical principles, functional PET imaging allows to assess parameters of tumor biology not easily accessible to conventional imaging such as metabolic activity, proliferation, adrenergic transmitter uptake or accumulation of cytostatic drugs in individual tumor manifestations. This article reviews recent developments of PET imaging with 2-[F-18]fluoro-deoxyglucose (FDG) in the Diagnosis of abdominal malignant tumors. Diagnosis of pancreatic carcinoma and its liver metastases, locoregional and distant recurrence as well as therapy control of colorectal cancer, nodal and extranodal staging and therapy monitoring of malignant lymphoma can be reliably achieved with PET. Encouraging clinical results and attractive new imaging concepts promise increasing use and importance of PET for imaging abdominal malignancies.

Abdominal Neoplasms↗

PubMed1999

[Lymph node staging of bladder neck carcinoma with positron emission tomography].

PET is a new method in nuclear medicine which examines the metabolism and not the morphology. Tumors show a higher rate of glycolysis than benign tissue and hence can be detected by radioactive glucose. This method has proved good for various tumors. In this study the lymph node staging of bladder cancer by PET was investigated. In 64 patients a PET of the pelvis after injection of fluorodeoxyglucose (FDG) was carried out preoperatively; the PET-results were compared with the histology of the OR specimen after classical pelvic lymphadenectomy. For lymph node staging positive nodes were found in 14 patients which was correct; a false-negative result was obtained in 7 patients. In 37 patients the PET-result was true-negative and in 6 patients false-positive resulting in a sensitivity of 67%, a specificity of 86% and an accuracy of 80%. Therefore, our PET results are encouraging and seem to be better than those obtained by classical staging procedures such as CT or MRI.

Adult↗

PubMed1999

Role of attenuation correction for fluorine-18 fluorodeoxyglucose positron emission tomography in the primary staging of malignant lymphoma.

Fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) has been shown to improve the diagnostic accuracy in the staging of malignant lymphomas, based on the metabolic signal of the lesions. This study was undertaken to determine the effect of attenuation correction in the detection of nodal and extranodal lesions in the primary staging of malignant lymphomas. Fifty-one untreated patients with either non-Hodgkin lymphoma (NHL, n=29) or Hodgkin's disease (n=22) were retrospectively evaluated. Static FDG-PET imaging of the trunk was performed following administration of 250-350 MBq FDG. Attenuation correction was performed in all patients. Images were reconstructed iteratively with or without transmission scans. Image evaluation was performed independently by two observers, who each examined one set of images (i.e. attenuation-corrected or uncorrected). The final decision as to whether results were discordant was reached by consensus of both observers. Out of 593 evaluated lymph node regions, 187 regions of increased FDG uptake were identified by both techniques. Differences between the readers concerned mainly the anatomical assignment of lesions (n=33) or the status (benign/malignant) of individual lesions (n=24). However, direct comparison of the two sets of images demonstrated very similar lesion contrast on attenuation-corrected and non-attenuation-corrected images. Real differences could be determined only in five regions (neck, 1; mediastinum, 1; upper abdomen, 3). Thirty-seven extranodal lesions (including lung, liver, spleen, bone marrow and soft tissue) were detected by both techniques without significant differences. It is concluded that in this study, attenuation correction did not improve the diagnostic accuracy of FDG-PET in the detection of lymph node or organ involvement during the primary staging of malignant lymphomas. Of more importance seemed to be the experience of the reader regarding the classification of a lesion's status the anatomical assignment, knowledge of physiological uptake and artefacts, and systematic and skillful examination of all regions scanned.

Adolescent↗

PubMed1999

Fluorodeoxyglucose positron emission tomography of soft tissue tumours: is a non-invasive determination of biological activity possible?

Since musculoskeletal tumours comprise a large heterogeneous group of entities with different biological behaviour, clinical diagnosis of such lesions can be very difficult. The aim of this prospective study was to assess the usefulness of 2-[F-18]-fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) in the non-invasive evaluation of soft tissue tumours. One hundred and two patients with suspected soft tissue neoplasms were investigated by FDG-PET. The uptake of FDG was evaluated semiquantitatively by determining the tumour to background ratio (TBR). All patients underwent biopsy, resulting in the histological detection of 39 high-grade sarcomas, 16 intermediate-grade sarcomas, 11 low-grade sarcomas, 25 benign tumours, 10 tumour-like lesions such as spontaneous myositis ossificans (n = 6) and one non-Hodgkin lymphoma. All lesions except for two lipomas disclosed an increased FDG uptake. Sarcomas showed significantly higher TBR values than latent or active benign lesions (P<0.001) and aggressive benign lesions (P<0.05). Using a TBR cut-off level of 3.0 for malignancy, sensitivity of FDG-PET was 97.0%, specificity 65.7% and accuracy 86. 3%. From our data there are three main conclusions: (1) Except for patients with pseudotumoral myositis ossificans, lesions with a TBR >3 were sarcomas (91.7%) or aggressive benign tumours (8.3%). (2) Tumours with a TBR <1.5 were latent or active benign lesions, exclusively. (3) The group with intermediate TBR values (<3 and >1. 5) comprised primarily latent or active benign lesions, but also four aggressive benign tumours and two low-grade sarcomas. Our data suggest that FDG-PET represents a useful tool for the evaluation of the biological activity of soft tissue neoplasms.

Female↗

PubMed1999

Preparation and evaluation of the rhenium-188-labelled anti-NCA antigen monoclonal antibody BW 250/183 for radioimmunotherapy of leukaemia.

Anti-NCA antigen antibody BW 250/183 (Anti-Granulocyte) localizes more than 50% of injected antibody dose to the bone marrow. Therefore, this antibody is promising for adjuvant conditioning radioimmunotherapy of bone marrow before bone marrow transplantation. To examine its potential use for radioimmunotherapy, we developed an efficient and reproducible technical protocol for labelling anti-NCA antigen antibody BW 250/183 with generator-produced rhenium-188, aiming at both high radiochemical yield and high specific activity. (188)Re-labelled BW 250/183 antibody was used in 12 patients with advanced leukaemia. Labelling of BW 250/183 with (188)Re was accomplished by the direct radiolabelling method using tris-(2-carboxyethyl) phosphine (TCEP) as the reducing agent. Twelve patients with recurrent acute or chronic leukaemia were treated with activities of 6.5-12.4 GBq of (188)Re-labelled BW 250/183. Standard gamma camera scintigraphy was used to evaluate the biodistribution, and a region of interest analysis together with the MIRDOSE 3.1 software was applied to determine the radiation doses to relevant tissues. The (188)Re-BW 250/183 antibody was labelled in high radiochemical yield, with high radiochemical purity (94%+/-3%) and specific activity (5.55-7.4 GBq/mg) within 1 h. The preliminary biodistribution studies showed persistent uptake of (188)Re-BW 250/183 in bone marrow. The radiation absorbed doses (mGy/MBq) delivered to the total body, red marrow, liver, spleen and kidneys were 0.13+/-0.02, 1.45+/-0.71, 0.43+/-0.21, 1.32+/-0.99 and 0.71+/-0. 17, respectively. TCEP reduction enabled the direct, fast and effective labelling of the monoclonal antibody BW 250/183 with (188)Re. Preliminary clinical results suggest delivery of a significant radiation dose to bone marrow and thus the potential for adjuvant conditioning therapy before BMT.

Adolescent↗

PubMed1999

Positron emission tomography with 18-fluorodeoxyglucose in the staging and follow-up of lymphoma in the chest.

The purpose of this retrospective study was to evaluate the accuracy of positron emission tomography (PET) using 18-F-fluorodeoxyglucose (FDG) in predicting lymphomatous involvement in the hilar and mediastinal regions in the staging and follow-up of patients with malignant lymphoma. One hundred forty-seven thoracic PET studies in 89 consecutive lymphoma patients were reviewed. Static FDG-PET imaging was performed following application of 270 MBq FDG (mean). Results of FDG-PET were compared with the findings of computed tomography (CT) in all patients and clinical follow-up examination. Eighty-nine of 147 (60%) PET studies showed no FDG uptake in the hilar or mediastinal regions, while 58 (40%) studies did detect FDG uptake in these regions. In 52 of 58 abnormal studies (90%), lymphomatous involvement of the hilar and/or mediastinal regions seen by CT was present. In the remaining six abnormal PET studies (10%), FDG uptake was considered as false-positive because of missing lesions on corresponding CT scans. In four patients false-positive FDG uptake was observed before treatment, in two patients after completion of therapy. In these two patients FDG uptake after therapy was caused by thymus hyperplasia. The remaining four cases before treatment remained unresolved. Sensitivity of FDG-PET was 96%, specificity 94%, positive predictive value 90%, and negative predictive value 98%, respectively. The present study suggests that FDG-PET has potential value in predicting lymphomatous involvement in the hilar and mediastinal regions. FDG-PET may obviate invasive diagnostic procedures in patients with lymphoma.

Adolescent↗

PubMed1999

Pericystic metabolic activity in alveolar echinococcosis: assessment and follow-up by positron emission tomography.

Information on parasite viability in alveolar echinococcosis (AE) cannot be obtained by conventional imaging techniques. We evaluated the glucose metabolism of AE lesions by use of [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) in 12 inoperable patients. Eight patients showed either perilesional or focal enhancement ("hot spots"), whereas 4 patients had nonenhancing (metabolically inactive) lesions. With PET, necrotic parasitic lesions and areas of enhanced metabolic activity could be clearly discriminated. Most notably, 3 of 8 patients with metabolically active lesions who were reexamined after chemotherapy treatment clearly showed improvement: the initial surrounding hot spots had disappeared in 2 of them, and had significantly decreased in 1. PET may prove valuable in assessing the efficacy of chemotherapy by showing the disappearance of metabolic activity and may also be useful for timely detection of relapses and metastases. Although costly and not readily available, FDG-PET is a promising tool toward improved management of AE and may thus help lower costs of long-term chemotherapy.

Adult↗

PubMed1999

Treatment of radioactive decay in pharmacokinetic modeling: influence on parameter estimation in cardiac 13N-PET.

Radioactive decay during measurement can be accounted for by either a decay correction of the measured data before modeling (DbM) or by direct implementation of decay into the pharmacokinetic model (DiM). The purpose of this study was to quantify the influence of the type of decay correction on the calculated parameters for the example of a three-compartment model used for the calculation of myocardial perfusion with 13N ammonia and positron emission tomography (PET). For a given input function [Ca(t)infinity t exp(-kt), k= 1.72/min] the tissue uptake for two parameter sets of K1, k2, k3, TBV were calculated for 20 frames (12 x 10 s, 4 x 30 s, 3 x 120 s, 1 x 300 s). These values were mathematically deteriorated by various noise levels according to Poisson statistics and fitted by a Levenberg-Marquardt algorithm. Estimated parameter means and coefficients of variation of the fitted parameters were calculated for the DbM and DiM case. The estimated parameter means for both decay correction methods were of comparable quality. The important measure for a single fit is the relative variability of the fitted parameters. This value is up to a factor 1.15 smaller for K1 obtained with DiM and a reasonable noise level of 10%. Therefore, decay correction should be taken into account during modeling to reduce the variability in the fitted parameters.

Algorithms↗

PubMed1999

Iterative reconstruction for attenuation correction in positron emission tomography: maximum likelihood for transmission and blank scan.

The quality of the attenuation correction strongly influences the outcome of the reconstructed emission scan in positron emission tomography. The calculation of the attenuation correction factors must take into account the Poisson nature of the radioactive decay process, because-for a reasonable scan duration-the transmission measurements contain lines of response with low count numbers in the case of large attenuation factors. Our purpose in this study is to investigate a maximum likelihood estimator for attenuation correction factor calculation in positron emission tomography, which incorporates the Poisson nature of the radioactive decay into transmission and blank measurement. Therefore, the correct maximum likelihood function is used to derive two estimators for the calculation of the attenuation coefficient image and the corresponding attenuation correction factors depending on the measured blank and transmission data. Log likelihood convergence, mean differences, and the mean of squared differences for the attenuation correction factors of a mathematical thorax phantom were determined and compared. The algorithms yield adequate attenuation correction factors, however, the algorithm taking the noise in the blank scan into account can perform better for noisy blank scans. We conclude that maximum likelihood-including blank likelihood-is advantageous to reconstruct attenuation correction factors for low statistic blank and good statistic transmission data. For normal blank and transmission statistics the implementation of the statistical nature of the blank is not mandatory.

Biophysical Phenomena↗

PubMed1999

Early detection and accurate description of extent of metastatic bone disease in breast cancer with fluoride ion and positron emission tomography.

PURPOSE: Previous studies have shown that bone metastases are revealed by magnetic resonance imaging (MRI) or bone marrow scintigraphy several months before they are visible by conventional bone scintigraphy (BS). We present a new approach for detecting bone metastases in patients with breast cancer. We compared findings obtained with fluoride ion (F-18) and positron emission tomography (PET) with those obtained with conventional BS. PATIENTS AND METHODS: Thirty-four breast cancer patients were prospectively examined using F-18-PET and conventional BS. F-18-PET and BS were performed within 3 weeks of each other. Metastatic bone disease was previously known to be present in six patients and was suspected (bone pain or increasing levels of tumor markers, Ca(2+), alkaline phosphatase) in 28 patients. Both imaging modalities were compared by patient-by-patient analysis and lesion-by-lesion analysis, using a five-point scale for receiver operating characteristic (ROC) curve analysis. A panel of reference methods was used, including MRI (28 patients), planar x-ray (17 patients), and spiral computed tomography (four patients). RESULTS: With F-18-PET, 64 bone metastases were detected in 17 patients. Only 29 metastases were detected in 11 patients with BS. As a result of F-18-PET imaging, clinical management was changed in four patients (11.7%). For F-18-PET, the area under the ROC curve was 0.99 on a lesion basis (for BS, it was 0.74; P <.05) and 1.00 on a patient basis (for BS, it was 0.82; P <.05). CONCLUSION: F-18-PET demonstrates a very early bone reaction when small bone marrow metastases are present, allowing accurate detection of breast cancer bone metastases. This accurate detection has a significant effect on clinical management, compared with the effect on management brought about by detection with conventional BS.

Adult↗

PubMed1999

Detection of liver metastases from pancreatic cancer using FDG PET.

UNLABELLED: We evaluated the potential of the glucose analog [18F]fluorodeoxyglucose (FDG) as a PET tracer for the hepatic staging in 168 patients designated for resective pancreatic surgery. METHODS: Metastatic liver disease was confirmed or excluded during surgery or with CT follow-up for at least 6 mo. Proven metastases were then retrospectively identified on preoperative CT (gold standard). Hepatic PET scans of all patients were interpreted blindly. Any focal FDG uptake was considered malignant. Both proven hepatic metastases and suspicious hepatic PET lesions were then compared, lesion by lesion, with CT. Standardized uptake values (SUV) and tumor-to-liver ratios (T/L) were determined for the most intense lesion of each patient. RESULTS: Sensitivity of FDG PET was 68% (15 of 22 patients). The lesion detection rate was 97% (28 of 29 metastases) for lesions >1 cm and 43% (16 of 37 metastases) for lesions < or = 1 cm. Specificity was 95% (138 of 146 patients). Six of eight patients with false-positive results had marked intrahepatic cholestasis (versus 3 of 15 patients with true-positive lesions), one had an infrahepatic abscess and one had a right basal pulmonary metastasis. The SUV and T/L were 4.6+/-1.4 and 2.3+/-1.1, respectively, for malignant lesions and 4.1+/-1.5 and 1.9+/-0.3, respectively, for false-positive lesions and therefore are of limited value. CONCLUSION: FDG PET provides reliable hepatic staging for lesions >1 cm. False-positive results are associated with the presence of marked intrahepatic cholestasis. For lesions < or = 1 cm, FDG PET can define malignancy in 43% of suspicious CT lesions in the absence of dilated bile ducts.

Aged↗