scholarly journals Mapping Metabolic Brain Activation during Human Volitional Swallowing: A Positron Emission Tomography Study Using [18F]fluorodeoxyglucose

2005 ◽  
Vol 25 (4) ◽  
pp. 520-526 ◽  
Author(s):  
Mary Louise Harris ◽  
Peter Julyan ◽  
Bhavna Kulkarni ◽  
David Gow ◽  
Anthony Hobson ◽  
...  

We have previously shown that labelled water positron emission tomography (H215O PET) can be used to identify regional cerebral blood flow (rCBF) changes in the human brain during volitional swallowing. (18F) fluorodeoxyglucose (FDG PET), by comparison, uses a glucose analogue to quantitatively measure regional cerebral glucose metabolism (rCMRglc) rather than rCBF. The main advantage of FDG PET is improved spatial resolution, and because of its pharmacodynamic properties, activation can be performed external to the scanner, allowing subjects to assume more physiologic positions. We therefore conducted a study of the brain's metabolic response while swallowing in the erect seated position, using FDG PET. Eight healthy male volunteers were studied with a randomised 2 scan paradigm of rest or water swallowing at 20-second intervals for 30 minutes. Data were analysed with SPM99 using multisubject conditions and covariates design. During swallowing, analysis identified increased rCMRglc ( P<0.01) in the following areas: left sensorimotor cortex, cerebellum, thalamus, precuneus, anterior insula, left and right lateral postcentral gyrus, and left and right occipital cortex. Decreased rCMRglc were also seen in the right premotor cortex, right and left sensory and motor association cortices, left posterior insula and left cerebellum. Thus, FDG PET can be applied to measure the brain metabolic activity associated with volitional swallowing and has the advantage of normal task engagement. This has implications for future activation studies in patients, especially those suffering swallowing problems after brain injury.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. 10577-10577
Author(s):  
Masaki Kanazu ◽  
Kaoru Maruyama ◽  
Masahiko Ando ◽  
Kazuhiro Asami ◽  
Mari Ishii ◽  
...  

10577 Background: Early prediction of clinical efficacy is of great value in cancer patients in avoiding unnecessary toxicities and giving them another chance for different treatments. This study aimed to assess the 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) at 3 days on treatment as an early predictor of clinical outcome in patients with advanced non-small cell lung cancer (NSCLC) treated with gefitinib and in those treated with cytotoxic chemotherapy. Methods: This study comprised two groups: patients with stage IIIB or IV NSCLC were treated with gefitinib (250mg) once daily (gefitinib group) or with carboplatin (AUC 6, day 1) plus paclitaxel (200mg/m2, day 1) q21 days (CP group) according to the physicians’ choice. FDG-PET was performed before, 3 days on and 28 days on each treatment. Reduction of tumor FDG uptake was assessed by using standardized uptake value (SUV). Metabolic response was defined as reduction of FDG uptake in the tumor ≥ 25% according to the criteria of the European Organization for Research and Treatment of Cancer. Metabolic response was correlated with clinical outcomes. Results: This study included 38 patients: 19 in gefitinib group and 19 in CP group. Reduction of SUV at 3days on treatment preceded tumor shrinkage more closely in gefitinib group. Metabolic response was significantly correlated with longer progression-free survival (PFS) in gefitinib cohort (median PFS 15.8 months [95% CI 13.2-18.4] vs. 3.7 months [95% CI 0.1-8.0], p < 0.001), but not in CP group (median PFS 5.7 months vs. 2.9 months, p = 0.054). Furthermore, metabolic response was significantly correlated with longer overall survival (OS) in gefitinib group (median OS 28.7 months [95%CI 23.5-33.9] vs. 9.8 months [95% CI 2.1-17.5], p = 0.009), but not in CP group (median OS 13.9 months vs. 10.5 months, p = 0.56). In multivariate analysis using Cox hazards models, metabolic response was a significant predictive factor of PFS and OS. Conclusions: Reduction of SUV levels on FDG-PET at 3 days on treatment may predict response and survival in gefitinib-treated patients with advanced NSCLC.


2003 ◽  
Vol 21 (14) ◽  
pp. 2651-2657 ◽  
Author(s):  
Wolfgang A. Weber ◽  
Volker Petersen ◽  
Burkhard Schmidt ◽  
Leishia Tyndale-Hines ◽  
Thomas Link ◽  
...  

Purpose: To prospectively evaluate the use of positron emission tomography with the glucose analog fluorodeoxyglucose (FDG-PET) to predict response to chemotherapy in patients with advanced non–small-cell lung cancer (NSCLC). Patients and Methods: Patients with stage IIIB or IV NSCLC scheduled to undergo platinum-based chemotherapy were eligible for this study. Patients were studied by FDG-PET before and after the first cycle of therapy. Based on previous studies, a reduction of tumor FDG uptake by more than 20% as assessed by standardized uptake values (SUV) was used as a criterion for a metabolic response. Furthermore, changes in tumor SUVs were compared with changes in FDG net-influx constants (Ki) and tumor/muscle ratios (t/m). Results: Fifty-seven patients were included in the study. There was a close correlation between metabolic response and best response to therapy according to Response Evaluation Criteria in Solid Tumors (P < .0001; sensitivity and specificity for prediction of best response, 95% and 74%, respectively). Median time to progression and overall survival were significantly longer for metabolic responders than for metabolic nonresponders (163 v 54 days and 252 days v 151 days, respectively). Similar results were obtained when Ki was used to assess tumor glucose use, whereas changes in t/m showed considerable overlap between responding and nonresponding tumors. Conclusion: In NSCLC, reduction of metabolic activity after one cycle of chemotherapy is closely correlated with final outcome of therapy. Using metabolic response as an end point may shorten the duration of phase II studies evaluating new cytotoxic drugs and may decrease the morbidity and costs of therapy in nonresponding patients.


2012 ◽  
Vol 30 (14) ◽  
pp. 1628-1634 ◽  
Author(s):  
Grant A. McArthur ◽  
Igor Puzanov ◽  
Ravi Amaravadi ◽  
Antoni Ribas ◽  
Paul Chapman ◽  
...  

Purpose Imaging with [18F]fluorodeoxyglucose (FDG) –positron emission tomography (PET) allows early recognition of a response to agents that target key driver mutations in human cancer. We aimed to determine the metabolic response rate to vemurafenib in patients with advanced BRAF-mutant melanoma. Patients and Methods Baseline and day 15 FDG-PET was evaluated in 31 patients with advanced melanoma treated in a phase I study of dose escalation of vemurafenib (PLX06-02), which included four patients treated at subtherapeutic doses and 24 patients treated at 960 mg twice a day, which is the maximum-tolerated dose of vemurafenib. Results All 27 patients treated at potentially therapeutic levels had at least a partial metabolic response, and three patients achieved a complete metabolic response. In the 27 patients, there was an 80% ± 3% reduction in the maximum standardized uptake value (SUVmax) of target lesions and an 87% ± 3% decrease in the percentage of injected dose (%ID) in all identified disease sites. There was a positive correlation between %ID in all identified disease and target-lesion SUVmax (r2 = 0.66; P < .001) that indicated a significant homogeneity of the response between lesions in individual patients. Although no relationship was found between the reduction in target lesion SUVmax and best response according to RECIST (Response Evaluation Criteria in Solid Tumors), there was a trend for patients with greater reductions in uptake of FDG to have longer progression-free survival. Conclusion FDG-PET is a useful marker of an early biologic response to vemurafenib. Little variability in PET response was found between lesions in individual patients, which suggested minimal intrapatient molecular heterogeneity. FDG-PET is a useful tool for the evaluation of the biologic impact of inhibiting mutant BRAF and may allow for the more effective development of novel agents.


2006 ◽  
Vol 24 (28) ◽  
pp. 4587-4593 ◽  
Author(s):  
Giovanni L. Ceresoli ◽  
Arturo Chiti ◽  
Paolo A. Zucali ◽  
Marcello Rodari ◽  
Romano F. Lutman ◽  
...  

Purpose Response evaluation with conventional criteria based on computed tomography (CT) is particularly challenging in malignant pleural mesothelioma (MPM) due to its diffuse pattern of growth. There is growing evidence that therapy-induced changes in tumor [18F]fluorodeoxyglucose (FDG) uptake as measured by positron emission tomography (PET) may predict response and patient outcome early in the course of treatment. Patients and Methods Patients with histologically proven MPM, not candidates to curative surgery, scheduled to undergo palliative chemotherapy with a pemetrexed-based regimen were eligible for this study. Patients were evaluated by FDG-PET and CT at baseline and after two cycles of therapy. A decrease of 25% or more in tumor FDG uptake as measured by standardized uptake value was defined as a metabolic response (MR). Best overall response from CT scans was determined according to previously published criteria. Results Twenty-two patients were included in the study, and 20 were assessable for early metabolic response with FDG-PET. Of these, eight were classified as responders (40%) and 12 as nonresponders (60%). Early MR was significantly correlated to median time-to-tumor progression (TTP) with a median TTP for metabolic responders of 14 months versus 7 months for nonresponders (P = .02). No correlation was found between TTP and radiologic response evaluated by CT. Patients with a MR had a trend toward longer overall survival. Conclusion The use of MR evaluated by FDG-PET in the assessment of treatment efficacy in MPM appears promising. Our observations need to be validated in a larger prospective series.


2005 ◽  
Vol 152 (4) ◽  
pp. 521-525 ◽  
Author(s):  
Athina Markou ◽  
Patrick Manning ◽  
Banu Kaya ◽  
Sam N Datta ◽  
Jamshed B Bomanji ◽  
...  

We report a case of a young woman with Cushing’s syndrome (CS), in whom although endocrine investigations and negative pituitary imaging were suggestive of ectopic ACTH secretion, the results of inferior petrosal sinus (IPS) sampling after coricotropin-releasing hormone (CRH) stimulation were suggestive of pituitary ACTH hypersecretion. 111In-labelled octreotide and high-resolution computer tomography (CT) revealed a lesion possibly responsible for the ACTH source in the thymus. Thymectomy confirmed concomitant ectopic CRH and probable ACTH production by a thymic neuroendocrine carcinoma. After an 8-year remission period the patient developed a clinical and biochemical relapse. A high-resolution computed tomography (CT) scan of the thorax showed a 2-cm nodule in the thymic bed, which was positive on a [18F]fluoro-2-deoxy-d-glucose ([18F]FDG) positron emission tomography (PET) scan. However, a repeated thymectomy did not result in remission. A repeat [18F]FDG PET study showed persistent disease in the thymic bed and also uptake in the adrenals. The patient underwent bilateral adrenalectomy, which resulted in clinical remission. A further [18F]FDG PET scan 8 months later showed no progression of the thymic tumor and confirmed complete excision of the adrenals. This is a rare case of concomitant CRH and ACTH secretion from a thymic carcinoid tumor; the case illustrates the usefulness of functional imaging with [18F]FDG PET in the diagnosis, management and follow-up of neuroendocrine tumors.


Diagnostics ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1041
Author(s):  
Jun Nakata ◽  
Kayako Isohashi ◽  
Yoshihiro Oka ◽  
Hiroko Nakajima ◽  
Soyoko Morimoto ◽  
...  

Assessment of tumor response during treatment is one of the most important purposes of imaging. Before the appearance of immunotherapy, response evaluation criteria in solid tumors (RECIST) and positron emission tomography response criteria in solid tumors (PERCIST) were, respectively, the established morphologic and metabolic response criteria, and cessation of treatment was recommended when progressive disease was detected according to these criteria. However, various types of immunotherapy have been developed over the past 20 years, which show novel false positive findings on images, as well as distinct response patterns from conventional therapies. Antitumor immune response itself causes 18F-fluorodeoxyglucose (FDG) uptake in tumor sites, known as “flare phenomenon”, so that positron emission tomography using FDG can no longer accurately identify remaining tumors. Furthermore, tumors often initially increase, followed by stability or decrease resulting from immunotherapy, which is called “pseudoprogression”, so that progressive disease cannot be confirmed by computed tomography or magnetic resonance imaging at a single time point. As a result, neither RECIST nor PERCIST can accurately predict the response to immunotherapy, and therefore several new response criteria fixed for immunotherapy have been proposed. However, these criteria are still controversial, and also require months for response confirmation. The establishment of optimal response criteria and the development of new imaging technologies other than FDG are therefore urgently needed. In this review, we summarize the false positive images and the revision of response criteria for each immunotherapy, in order to avoid discontinuation of a truly effective immunotherapy.


Diagnostics ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 230
Author(s):  
Giulia Ferrarazzo ◽  
Silvia Chiola ◽  
Selene Capitanio ◽  
Maria Isabella Donegani ◽  
Alberto Miceli ◽  
...  

2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography/computed tomography (FDG PET/CT) has an established clinical value in the diagnosis and initial staging of multiple myeloma (MM). In the last ten years, a vast body of literature has shown that this tool can also be of high relevance for monitoring therapy responses, making it the recommended imaging approach in this field. Starting from the strengths and weaknesses of radiological imaging in MM, the present review aims to analyze FDG PET/CT’s current clinical value focusing on therapy response assessment and objective interpretation criteria for therapy monitoring. Given the potential occurrence of patients with MM showing non-FDG-avid bone disease, new opportunities can be provided by non-FDG PET tracers. Accordingly, the potential role of non-FDG PET tracers in this setting has also been discussed.


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