ABSTRACT
UNLABELLED: The purpose of this study was to determine whether dual-phase (18)F-FDG PET could be a prognostic factor for adenocarcinoma of the lung. METHODS: One hundred patients with histologically proven adenocarcinoma of the lung were included in this retrospective analysis. All patients underwent dual-phase pretherapy (18)F-FDG PET for which, after the intravenous administration of (18)F-FDG, both early (approximately 60 min) and delayed (approximately 90 min) PET were acquired. The percentage change in the maximal standardized uptake values (SUVmax) of the cancer between the early and the delayed images was calculated. Overall survival of the SUVmax change over time together with the known prognostic factors were calculated by the Kaplan-Meier method and evaluated with the log-rank test. The prognostic significance was assessed by univariate and multivariate analyses. RESULTS: Statistical analysis showed that SUVmax change over time between the early and the delayed PET was a strong independent predictor of outcome for lung adenocarcinoma. A cutoff of 25% change for SUVmax over time showed the best discriminative value. Patients with more than 25% increase in SUVmax had a median survival of 15 mo, compared with 39 mo for those with less than 25% increase in SUVmax. CONCLUSION: Dual-phase (18)F-FDG PET reflects the dynamics of glucose metabolism. Our findings suggest that the percentage SUVmax change over time is a strong prognostic factor in patients with lung adenocarcinoma and can be complementary to the other well-known factors.
Subject(s)
Adenocarcinoma/diagnostic imaging , Adenocarcinoma/diagnosis , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/diagnosis , Positron-Emission Tomography , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Biological Transport , Female , Fluorodeoxyglucose F18/metabolism , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Male , Middle Aged , Multivariate Analysis , Prognosis , Regression Analysis , Retrospective Studies , Tumor BurdenABSTRACT
A number of noninvasive imaging techniques have been used for the evaluation of bone marrow, including magnetic resonance imaging (MRI) and bone marrow scintigraphy. The appearance of bone marrow on MRI varies considerably depending on the proportion of red and yellow marrow, and the composition of the red marrow and its distribution with relation to age and sex. The composition of bone marrow also can vary under physiological and pathological conditions. MRI is a highly sensitive technique for evaluating the bone marrow, but it is limited in its practical use for whole-body bone marrow screening. Bone marrow scintigraphy with radiolabeled compounds such as technetium-99m-labeled nanocolloid and monoclonal antibodies has the advantage of evaluating the entire bone marrow, and has been used for the diagnosis of various bone marrow disorders. In addition, (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging can be used to evaluate bone marrow metabolism and disease and to provide information about the state of the primary tumor, lymph nodes, and distant metastases. Understanding of the appearance of normal bone marrow, including age- and sex-specific differences with each of these imaging modalities, is essential to permit accurate diagnosis of benign and malignant bone marrow disorders. We present a review of MRI and scintigraphy of normal bone marrow with some emphasis on FDG-PET imaging in assessing marrow activity in normal and abnormal states and also present preliminary data regarding normal age-related changes in bone marrow through use of FDG-PET, as well as the role of segmentation of bone marrow on MRI for quantitative calculation of the metabolic volumetric product for red marrow metabolism using FDG-PET.
