title: [The value of FDG-PET/CT in the evaluation of patients with a pulmonary nodule and a previous malignant disease].
abstract: BACKGROUND
  Patients with primary malignant disease undergoing oncological surveillance, upon completion of their treatment, are a unique population that is gradually growing. Therefore, the number of patients with a pulmonary nodule and a previous malignant disease has increased over recent years. In order to select appropriate management for these patients, a few questions should be answered: Is it a malignant lesion? Secondly, is it primary or metastatic? Is it the only one? In the past, several imaging and invasive diagnostic procedures were used to clarify theses uncertainties. However, in many cases the results were equivocal and it was difficult to establish treatment policy. In recent years PET/CT-FDG was found to be specific, sensitive and accurate in the evaluation and staging of patients with primary malignant disease. In this study we analyzed the accuracy and value of PET/CT-FDG in patients with primary malignant disease and an indeterminate pulmonary nodule.
  
  
  METHODS
  Patients with primary malignant disease in the past and undefined pulmonary nodule/s were recruited. Computerized retrospective screening was performed. The specificity, sensitivity, positive and negative predictive value of PET/CT-FDG were calculated. The influence of the PET results on the clinical policy was evaluated.
  
  
  RESULTS
  Forty one patients with previous malignant disease entered the study. PET/CT-FDG was positive in 15 cases. In 13 patients (87%) the FDG positive nodule was found to be malignant. In 26 patients the PET/CT was negative. In 19 (73%) diagnosis of non-malignant nodule was confirmed. The positive and negative predictive value of PET/CT-FDG for metastatic disease was 87% and 91% respectively and the accuracy 86%.
  
  
  CONCLUSIONS
  The results of the present study demonstrate that PET/CT-FDG is a very valuable tool in the evaluation of patients with previous primary malignant disease and a pulmonary nodule. This imaging technique was able to clarify most of the thoracic surgeon's uncertainties and provided enough data to choose the optimal treatment strategy.
authors.affiliation: Department of General Thoracic Surgery, Rambam Medical Center, Haifa. a_ben_nun@rambam.health.gov.il
authors.forename: Alon
authors.initials: A
authors.lastname: Ben-Nun
authors.forename: Michael
authors.initials: M
authors.lastname: Orlovsky
authors.forename: Anson Lael
authors.initials: AL
authors.lastname: Best
authors.forename: Rachel
authors.initials: R
authors.lastname: Bar Shalom
mesh_terms: D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012008:Recurrence; D015203:Reproducibility of Results; D003074:Solitary Pulmonary Nodule / Q000000981:diagnostic imaging*; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18