title: Staging for Remnant Gastric Cancer: The Metastatic Lymph Node Ratio vs. the UICC 7th Edition System.
abstract: Unlike primary gastric cancer, a remnant gastric cancer (RGC) staging system has not been established. The retrieved lymph node counts (RLN) in RGC is generally lower than that in primary gastric cancer, so it is unclear whether positive lymph node count reflects the RGC patient's survival. Therefore, the lymph node ratio (LR) may be more useful for RGC staging than the 7th edition UICC classification.
  
  
  
  Patients (n = 191) who underwent gastrectomy with curative intent for RGC participated in this study. LR was classified as LR = 0, 0 < LR ≤ 0.1, 0.1 < LR ≤ 0.4, and 0.4 < LR. Modified TNM staging (mTNM-LR) was established by combining the pT (7th UICC) with LR. The predictive accuracy of LR and mTNM-LR was compared with that of the pN (7th UICC) and TNM (7th UICC), respectively.
  
  
  
  The mean RLN was 14.4 and that of 128 patients (67 %) was ≤15. Fifty-one patients (27 %) had metastatic lymph nodes. Multivariable analyses revealed that pT (7th UICC) (p < 0.001) and pN (7th UICC) (p = 0.001), but not LR, were independent risk factors for overall survival. The overall c-index (95 % confidence interval) of each staging system was as follows: pN (7th UICC): 0.700 (0.627-0.771); LR: 0.701 (0.627-0.775), TNM (7th UICC): 0.808 (0.761-0.870); mTNM-LR: 0.807 (0.737-0.871). There were no significant differences in the predictive accuracy between pN (7th UICC) and LR, and TNM (7th UICC) and mTNM-LR.
  
  
  
  LR was not superior to pN (7th UICC). Thus, the 7th edition UICC classification is a practical and reliable staging system for RGC.
authors.affiliation: Department of Surgery, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Republic of Korea.|Department of Gastric Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Nakagawa
authors.affiliation: Department of Surgery, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Yoon Young
authors.initials: YY
authors.lastname: Choi
authors.affiliation: Department of Surgery, Gastric Cancer Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. ugids@naver.com.
authors.forename: Ji Yeong
authors.initials: JY
authors.lastname: An
authors.affiliation: Biostatistics Collaboration Unit, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jung Hwa
authors.initials: JH
authors.lastname: Hong
authors.affiliation: Department of Surgery, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jong Won
authors.initials: JW
authors.lastname: Kim
authors.affiliation: Department of Surgery, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Hyung-Il
authors.initials: HI
authors.lastname: Kim
authors.affiliation: Department of Surgery, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Republic of Korea.|Brain Korea 21 PLUS Project for Medical Science, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jae-Ho
authors.initials: JH
authors.lastname: Cheong
authors.affiliation: Department of Surgery, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Woo Jin
authors.initials: WJ
authors.lastname: Hyung
authors.affiliation: Department of Surgery, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Seung Ho
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Department of Surgery, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Republic of Korea.|Brain Korea 21 PLUS Project for Medical Science, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sung Hoon
authors.initials: SH
authors.lastname: Noh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017024:Chemotherapy, Adjuvant; D018572:Disease-Free Survival; D005260:Female; D005743:Gastrectomy; D018530:Gastric Stump / Q000473:pathology*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging / Q000379:methods*; D013274:Stomach Neoplasms / Q000473:pathology* / Q000628:therapy; D015996:Survival Rate; D047368:Tumor Burden