title: Lymphoscintigraphy in detection of the regional lymph node involvement in gastric cancer.
abstract: BACKGROUND
  Involvement of regional lymph node is a critical sign in prognosis of gastric cancer. Radiological techniques are commonly used to evaluate the extension of gastric cancer. But their sensitivity and specificity are low especially in the early stage. Our aim was to assess the value of gastric lymphoscintigraphy in identifying regional lymph node involvement in patients with gastric cancer, as compared to the abdominal ultrasonography, computed tomography and postoperative histopathological evaluation.
  
  
  METHODS
  50 patients (12 females) with a median age of 61 years (range, 35-73 years) were included in the study. Pre-operative staging in all cases included upper gastrointestinal endoscopy and biopsy, followed by ultrasound, computed tomography and lymphoscintigraphy. 148 MBq Technetium-99m lymphoscint was injected around the tumour during endoscopy and immediately after injection, anterior, lateral and posterior images were taken in 5-min intervals using a gamma camera. Findings were compared to the findings of other tests. The sensitivity, specificity, positive predictive value, and negative predictive value of each test were calculated and compared.
  
  
  RESULTS
  Histologically, 68% of cases (34/50) had metastasis in regional lymph nodes and all cases were accurately diagnosed by lymphoscintigraphy. Lymphoscintigraphy was significantly more sensitive for detecting lymph node involvement (P < 0.01). Both abdominal ultrasonography and CT had very low sensitivity in identifying lymph nodes.
  
  
  CONCLUSIONS
  Lymphoscintigraphy is a promising test in the identification of regional lymph nodes pre-operatively in patients with gastric cancer. It might help the surgeon to plan the extent of dissection before surgery which may decrease postoperative complications related to unnecessary extensive lymph node dissection.
authors.affiliation: Department of Surgery, Ankara Numune Teaching and Research Hospital, Ankarra, Turkey. mahir.ozmen@tubitak.gov.tr
authors.forename: M Mahir
authors.initials: MM
authors.lastname: Ozmen
authors.forename: Baris
authors.initials: B
authors.lastname: Zulfikaroglu
authors.forename: N Ozlem
authors.initials: NO
authors.lastname: Kucuk
authors.forename: Necdet
authors.initials: N
authors.lastname: Ozalp
authors.forename: Gulseren
authors.initials: G
authors.lastname: Aras
authors.forename: Tankut
authors.initials: T
authors.lastname: Koseoglu
authors.forename: Mahmut
authors.initials: M
authors.lastname: Koç
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000000981:diagnostic imaging*; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging*; D008207:Lymphatic Metastasis / Q000175:diagnosis / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D012680:Sensitivity and Specificity; D013274:Stomach Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed