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Query: UMLS:C0242379 (lung cancer)
 71,905 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Accurate staging of cancer has a critical role in optimal patient management. Fluorine-18 fluorodeoxyglucose positron emission tomography (FDG PET) is superior to CT in the detection of local and distant metastases in patients with non-small cell lung cancer. Although Tc-99 m methylene diphosphonate (MDP) bone scanning is well established in the evaluation of bone metastases, there are conflicting reports on the use of FDG PET in the evaluation of skeletal metastases. We report on a patient with locally advanced lung carcinoma in whom FDG PET accurately identified previously unsuspected widespread asymptomatic bone metastases (bone scan and X-rays negative, confirmed on MRI). Assessment of glucose metabolism with FDG PET might represent a more powerful tool to detect bone metastases in lung cancer compared with conventional bone scans.
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PMID:Detection of occult bone metastases of lung cancer with fluorine-18 fluorodeoxyglucose positron emission tomography. 1523 Jul 58

The information provided by functional images may be used to guide radiotherapy planning by identifying regions that require higher radiation dose. In this work we investigate the dosimetric feasibility of delivering dose to lung tumors in proportion to the fluorine-18-fluorodeoxyglucose activity distribution from positron emission tomography (FDG-PET). The rationale for delivering dose in proportion to the tumor FDG-PET activity distribution is based on studies showing that FDG uptake is correlated to tumor cell proliferation rate, which is shown to imply that this dose delivery strategy is theoretically capable of providing the same duration of local control at all voxels in tumor. Target dose delivery was constrained by single photon emission computed tomography (SPECT) maps of normal lung perfusion, which restricted irradiation of highly perfused lung and imposed dose-function constraints. Dose-volume constraints were imposed on all other critical structures. All dose-volume/function constraints were considered to be soft, i.e., critical structure doses corresponding to volume/function constraint levels were minimized while satisfying the target prescription, thus permitting critical structure doses to minimally exceed dose constraint levels. An intensity modulation optimization methodology was developed to deliver this radiation, and applied to two lung cancer patients. Dosimetric feasibility was assessed by comparing spatially normalized dose-volume histograms from the nonuniform dose prescription (FDG-PET proportional) to those from a uniform dose prescription with equivalent tumor integral dose. In both patients, the optimization was capable of delivering the nonuniform target prescription with the same ease as the uniform target prescription, despite SPECT restrictions that effectively diverted dose from high to low perfused normal lung. In one patient, both prescriptions incurred similar critical structure dosages, below dose-volume/function limits. However, in the other patient, critical structure dosage from the nonuniform dose prescription exceeded dose-volume/function limits, and greatly exceeded that from the uniform dose prescription. Strict compliance to dose-volume/ function limits would entail reducing dose proportionality to the FDG-PET activity distribution, thereby theoretically reducing the duration of local control. Thus, even though it appears feasible to tailor lung tumor dose to the FDG-PET activity distribution, despite SPECT restrictions, strict adherence to dose-volume/function limits could compromise the effectiveness of functional image guided radiotherapy.
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PMID:Feasibility of optimizing the dose distribution in lung tumors using fluorine-18-fluorodeoxyglucose positron emission tomography and single photon emission computed tomography guided dose prescriptions. 1525 48

Positron-emission tomography (PET) with 18-fluorodeoxyglucose has a role in the diagnosis and staging of lung cancer, but is also appealing for assessment of prognosis and treatment. A systematic search of the published work shows good evidence that [(18)F]FDG uptake on PET has independent prognostic value in newly diagnosed non-small-cell lung cancer. PET is a sensitive method of measuring the biological effects of anticancer therapy, but until better standardisation and large-scale experience is available, it should only be used for additional assessments of early response in clinical trials. Further studies are needed to define the role of [(18)F]FDG-PET in restaging after induction therapy in multimodality approaches for locally advanced lung cancer. The assessment of prognosis by [(18)F]FDG-PET is less substantiated in treated lung cancer than in newly diagnosed patients. Good prospective evidence documents the effectiveness of [(18)F]FDG-PET over CT in the correct identification of recurrent lung cancer.
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PMID:Positron-emission tomography in prognostic and therapeutic assessment of lung cancer: systematic review. 1533 82

Proper selection and interpretation of imaging studies is essential to provide optimal treatment to patients who have lung cancer. The following combines the recommendations of the American College of Chest Physicians [74] and the authors' current clinical practice guidelines: --All patients who have known or suspected lung cancer should undergo a CT of the chest and upper abdomen. --An FDG-PET study should be performed, if available. --Mediastinoscopy should be performed in all patients except those who have peripheral small (<2 cm) tumors and no evidence of N2 disease on CT or PET imaging. --MRI should be performed for tumors of the superior sulcus to define the relationship of the tumor to adjacent neurovascular structures. --Patients who have neurologic signs or symptoms should undergo a brain imaging study (CT or MRI). --Screening for extrathoracic disease is not necessary in asymptomatic patients who have clinical stage I or II disease.
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PMID:Current state of imaging for lung cancer staging. 1538 4

The concept of equivalent uniform dose (EUD) has been suggested as a means to quantitatively consider heterogeneous dose distributions within targets. Tumor cell density/function is typically assumed to be uniform. We herein propose to use 18F-labeled 2-deoxyglucose (FDG) positron emission tomography (PET) tumor imaging activity as a surrogate marker for tumor cell density to allow the EUD concept to include intratumor heterogeneities and to study its effect on EUD calculation. Thirty-one patients with lung cancer who had computerized tomography (CT)-based 3D planning and PET imaging were studied. Treatment beams were designed based on the information from both the CT and PET scans. Doses were calculated in 3D based on CT images to reflect tissue heterogeneity. The EUD was calculated in two different ways: first, assuming a uniform tumor cell density within the tumor target; second, using FDG-PET activity (counts/cm3) as a surrogate for tumor cell density at different parts of tumor to calculate the functional-imaging-weighted EUD (therefore will be labeled fEUD for convenience). The EUD calculation can be easily incorporated into the treatment planning process. For 28/31 patients, their fEUD and EUD differed by less than 6%. Twenty-one of these twenty-eight patients had tumor volumes < 200 cm3. In the three patients with larger tumor volume, the fEUD and EUD differed by 8%-14%. Incorporating information from PET imaging to represent tumor cell density in the EUD calculation is straightforward. This approach provides the opportunity to include heterogeneity in tumor function/metabolism into the EUD calculation. The difference between fEUD and EUD, i.e., whether including or not including the possible tumor cell density heterogeneity within tumor can be significant with large tumor volumes. Further research is needed to assess the usefulness of the fEUD concept in radiation treatment.
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PMID:Using FDG-PET activity as a surrogate for tumor cell density and its effect on equivalent uniform dose calculation. 1548 40

A considerable number of false negative cases in FDG-PET were seen in small-cell lung cancer, despite the usefulness of this imaging modality. We investigated the correlation between FDG-PET results and the clinicopathological findings in small lung cancers less than 3 cm in size. Fifty-one consecutive cases of surgically resected small lung cancers scanned preoperatively by FDG-PET was assessed. The medical records of each case were reviewed for the maximum tumor size in the CT findings, histology, grade of differentiation, lymphatic and vascular invasion, pleural invasion, lymph node stage, serum level of carcinoembryonic antigen (CEA), and CT findings. All of the 5 cases (4 adenocarcinomas, 1 small-cell carcinoma) less than 1 cm in size were false negatives. In the 46 cases 1-3 cm in size (34 adenocarcinomas, 9 squamous sell carcinomas, 2 large sell carcinomas, 1 small cell carcinoma), false negative results were seen in 8 of 15 cases of well-differentiated adenocarcinoma (53%). In the 8 false negative cases, 1 (13%) lymphatic vessel invasion (ly), 0 (0%) vascular vessel invasion (v), 0 (0%) pleural invasion (p), 0 (0%) lymph node metastasis, 0 (0%) high serum level of CEA, and 5 (63%) cases showing ground-glass opacity on CT were observed. There were significant differences in the factors ly, v, CEA, and CT findings between the 8 false-negative cases and the 26 true positive cases with adenocarcinoma (p < 0.01-0.05). Lung cancers < 1 cm in size cannot be detected in FDG-PET. Adenocarcinomas of the lung 1-3 cm in size with false negatives in FDG-PET showed significantly less invasiveness than the true positives.
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PMID:[False negative cases of F-18 fluorodeoxyglucose-positron emission tomography (FDG-PET) imaging in small lung cancer less than 3 cm in size]. 1550 Jan 45

Correctly staging lung cancer is extremely important because treatment options and prognosis differ significantly by stage. In this review, the performance characteristics of positron emission tomography using F-18-fluoro-deoxyglucose (FDG PET) for staging the mediastinum are given in comparison with other non-invasive imaging modalities on the basis of current literature data. There are three meta-analyses demonstrating that FDG PET is more accurate than CT for detecting mediastinal metastases. First publications suggest that dual-modality PET-CT may provide a further gain in accuracy. Additionally, whole-body FDG PET provides information on M-staging and prognosis. Data comparing FDG PET with other functional imaging modalities or endoscopic ultrasound are limited. The necessity of a histological confirmation of PET results is still under discussion.
Lung Cancer 2004 Aug
PMID:FDG PET: advantages for staging the mediastinum? 1555 84

Mediastinal lymph-node involvement is still the major prognostic factor in NSCLC. Currently, cervical mediastinoscopy is the gold standard of mediastinal lymph-node staging. However, less invasive methods such as transbronchial or transoesophageal FNA are becoming more popular and might replace or adjunct mediastinoscopy under certain circumstances. It has been clearly shown that FDG PET is more accurate than CT for the detection of mediastinal lymph-node metastases. However, a positive finding on the PET scan implies that these lymph nodes have to be examined by invasive methods (e.g. mediastinoscopy). It has been demonstrated that PET might be useful in order to detect non-symptomatic distant metastases. The method of pathological analysis of the lymph nodes is critical for the correct determination of the N stage.
Lung Cancer 2004 Aug
PMID:Mediastinal staging (take home messages). 1555 87

Computed tomography (CT) has traditionally been the standard radiographic modality for diagnosing and monitoring non-small cell; lung cancer (NSCLC) after treatment. Given the limitations of CT, the utility of 18F-fluoro-2-deoxy-glucose positron emission tomography (FDG-PET) has been investigated for the management of NSCLC, with promising findings. Its adjunctive role with CT in diagnosing and staging disease is well established. FDG-PET also has been found to be a valuable tool for radiation treatment planning because it improves the precision of lesion definition. More recently, its value for determining clinical response both during and after treatment has been explored. This review highlights the various applications of FDG-PET in the diagnosis and management of NSCLC as corroborated by clinical data, with considerations of future directions.
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PMID:Response to radiation. 1555 7

This study was performed to investigate the feasibility of FDG- and L-[methyl-11C]methionine (Met)-PET for the follow up of lung cancer after stereotactic radiotherapy (SRT). Nine patients (pt) with solitary lung cancer underwent SRT. Met- and FDG-PET studies were performed one week before SRT and from one week to 8 months after SRT. Responses to SRT were complete in 2 pt and partial in 7 pt. Met- and FDG-PET scan showed high tracer uptake in all tumors before SRT. After SRT, standardized uptake values (SUV) of FDG and Met changed concordantly. Both decreased with time in 5 pt but did not decrease steadily in 4 pt, where 2 pt showed an increase at 1 to 2 weeks after SRT and 2 pt showed an increase at more than 3 months after SRT. The former appears to reflect the acute reaction to SRT and the latter radiation-induced pneumonitis. Although the addition of Met-PET did not provide additional information over FDG-PET, FDG- and Met-PET could be used to evaluate the treatment effect of SRT.
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PMID:18F-FDG and 11C-methionine PET for evaluation of treatment response of lung cancer after stereotactic radiotherapy. 1568 47


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