title: FDG-PET/CT lymph node staging after neoadjuvant chemotherapy in patients with adenocarcinoma of the esophageal-gastric junction.
abstract: The aim of the analysis was to assess the accuracy of various FDG-PET/CT parameters in staging lymph nodes after neoadjuvant chemotherapy.
  
  
  
  In this prospective study, 74 patients with adenocarcinoma of the esophageal-gastric junction were examined by FDG-PET/CT in the course of their neoadjuvant chemotherapy given before surgical treatment. Data from the final FDG-PET/CT examinations were compared with the histology from the surgical specimens (gold standard). The accuracy was calculated for four FDG-PET/CT parameters: (1) hypermetabolic nodes, (2) large nodes, (3) large-and-medium large nodes, and (4) hypermetabolic or large nodes.
  
  
  
  In 74 patients, a total of 1540 lymph nodes were obtained by surgery, and these were grouped into 287 regions according to topographic origin. Five hundred and two nodes were imaged by FDG-PET/CT and were grouped into these same regions for comparison. In the analysis, (1) hypermetabolic nodes, (2) large nodes, (3) large-and-medium large nodes, and (4) hypermetabolic or large nodes identified metastases in particular regions with sensitivities of 11.6%, 2.9%, 21.7%, and 13.0%, respectively; specificity was 98.6%, 94.5%, 74.8%, and 93.6%, respectively. The best accuracy of 77.7% reached the parameter of hypermetabolic nodes. Accuracy decreased to 62.0% when also smaller nodes (medium-large) were taken for the parameter of metastases.
  
  
  
  FDG-PET/CT proved low sensitivity and high specificity. Low sensitivity was based on low detection rate (32.6%) when compared nodes imaged by FDG-PET/CT to nodes found by surgery, and in inability to detect micrometastases. Sensitivity increased when also medium-large LNs were taken for positive, but specificity and accuracy decreased.
authors.affiliation: PET Center, Hospital Na Homolce, Roentgenova 2, 150 30, Prague 5, Czech Republic. pavel.fencl@homolka.cz.
authors.forename: Pavel
authors.initials: P
authors.lastname: Fencl
authors.affiliation: PET Center, Hospital Na Homolce, Roentgenova 2, 150 30, Prague 5, Czech Republic.
authors.forename: Otakar
authors.initials: O
authors.lastname: Belohlavek
authors.affiliation: 3rd Clinic of Surgery, First Faculty of Medicine, Charles University in Prague and University Hospital Motol, V Uvalu 84, Praha 5, 150 06, Czech Republic.
authors.forename: Tomas
authors.initials: T
authors.lastname: Harustiak
authors.affiliation: Clinic of Oncology, First Faculty of Medicine, Charles University in Prague and General Teaching Hospital, U Nemocnice 2, Praha 2, 128 08, Czech Republic.
authors.forename: Milada
authors.initials: M
authors.lastname: Zemanova
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D017024:Chemotherapy, Adjuvant; D004938:Esophageal Neoplasms / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery; D004943:Esophagogastric Junction / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D000072078:Positron Emission Tomography Computed Tomography; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: Accuracy; Esophageal adenocarcinoma; FDG-PET/CT; Neoadjuvant chemotherapy; Nodal staging