title: Does a minimum number of 16 retrieved nodes affect survival in curatively resected gastric cancer?
abstract: BACKGROUND
  According to the TNM classification, the analysis of 16 or more lymph nodes is required for the appropriate staging of gastric cancer. The aim of this study was to evaluate whether this number of resected lymph nodes also affects survival.
  
  
  METHODS
  This was a multicenter retrospective study based on an analysis of 992 patients with gastric adenocarcinoma who underwent curative resection between January 1980 and December 2009. Patients were classified according to the number of resected lymph nodes (<16 and ≥16 lymph nodes), the anatomical extent of lymph node dissection (D2 vs. D1), and the staging criteria of the seventh edition of the UICC/AJCC TNM staging system. Survival estimates were determined by univariate and multivariate analyses.
  
  
  RESULTS
  Based on the univariate and multivariate analyses, the resection of 16 or more lymph nodes was associated with significantly better survival [p = 0.002; hazard ratio (HR) (95% confidence interval [CI]): 0.519 (0.345-0.780)]. Patients with a lymph node count <16 had a significantly worse survival rate than patients with a lymph node count ≥16 in the pN0 (p = 0.001), pN1 (p = 0.007) and pN2 (p = 0.001) stages. In the majority of cases, ≥16 lymph nodes were retrieved when D2 dissection was performed.
  
  
  CONCLUSIONS
  In gastric cancer the retrieval of less than 16 lymph nodes may cause inaccurate staging and/or inadequate treatment, thus affecting survival rates. These patients should be considered a high-risk group for stage migration and worse survival compared with those who have a retrieval of more than 16 lymph nodes.
authors.affiliation: General Surgery Unit, Department of Surgery, "A. Gemelli" University Hospital, Catholic University of Rome, Largo A. Gemelli 8, Rome 00167, Italy. Electronic address: biondi.alberto@tiscali.it.
authors.forename: A
authors.initials: A
authors.lastname: Biondi
authors.affiliation: General Surgery Unit, Department of Surgery, "A. Gemelli" University Hospital, Catholic University of Rome, Largo A. Gemelli 8, Rome 00167, Italy. Electronic address: ddugo@rm.unicatt.it.
authors.forename: D
authors.initials: D
authors.lastname: D'Ugo
authors.affiliation: Surgical Oncology Unit - Humanitas Clinical and Research Center, Via Manzoni 56, Rozzano 20089, MI, Italy. Electronic address: fcm.cananzi@hotmail.it.
authors.forename: F C M
authors.initials: FC
authors.lastname: Cananzi
authors.affiliation: Digestive Surgery Unit, Department of Surgery, "A. Gemelli" University Hospital, Catholic University of Rome, Italy. Electronic address: valeriopapa@msn.com.
authors.forename: V
authors.initials: V
authors.lastname: Papa
authors.affiliation: Division of Surgical Oncology, Azienda Ospedaliera Citta della Salute e della Scienza di Torino, Turin, Italy. Electronic address: borasi.andrea@gmail.com.
authors.forename: A
authors.initials: A
authors.lastname: Borasi
authors.affiliation: General Surgery Unit, Department of Surgery, "A. Gemelli" University Hospital, Catholic University of Rome, Largo A. Gemelli 8, Rome 00167, Italy. Electronic address: federico.sicoli@yahoo.it.
authors.forename: F
authors.initials: F
authors.lastname: Sicoli
authors.affiliation: Division of Surgical Oncology, Azienda Ospedaliera Citta della Salute e della Scienza di Torino, Turin, Italy. Electronic address: mdegiuli@hotmail.com.
authors.forename: M
authors.initials: M
authors.lastname: Degiuli
authors.affiliation: Digestive Surgery Unit, Department of Surgery, "A. Gemelli" University Hospital, Catholic University of Rome, Italy. Electronic address: gbdoglietto@rm.unicatt.it.
authors.forename: G
authors.initials: G
authors.lastname: Doglietto
authors.affiliation: General Surgery Unit, Department of Surgery, "A. Gemelli" University Hospital, Catholic University of Rome, Largo A. Gemelli 8, Rome 00167, Italy. Electronic address: rpersiani@rm.unicatt.it.
authors.forename: R
authors.initials: R
authors.lastname: Persiani
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality / Q000556:secondary* / Q000601:surgery; D000367:Age Factors; D000704:Analysis of Variance; D005743:Gastrectomy / Q000379:methods; D006801:Humans; D053208:Kaplan-Meier Estimate; D008197:Lymph Node Excision / Q000401:mortality*; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012737:Sex Factors; D013274:Stomach Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D015996:Survival Rate
keywords: Gastric cancer; Lymph node; Prognosis; Staging