title: Poorly Differentiated Carcinoma Component in Submucosal Layer Should be Considered as an Additional Criterion for Curative Endoscopic Resection of Early Gastric Cancer.
abstract: Some studies have reported lymph node metastasis (LNM) in early gastric cancer (EGC) cases meeting the expanded criteria for endoscopic resection. Therefore, we investigated whether a minor poorly differentiated carcinoma (PDC) component in the submucosal (SM) layer affects LNM in differentiated EGC.
  
  
  
  We performed surgery in 1096 patients with differentiated SM gastric cancer and compared the clinicopathologic features of node-positive (n = 194) and node-negative (n = 902) differentiated SM cancer, with special reference to the portion of PDC component in the SM layer.
  
  
  
  When we categorized patients by the proportion of PDC component in the SM layer, we found 840 patients had <5 % and 256 patients had ≥5 % PDC components in the SM layer. The ≥5 % group was significantly associated with younger age, female sex, moderate differentiation, deep SM invasion, lymphovascular invasion (LVI), perineural invasion, and LNM. In multivariate analysis, middle third location, moderate differentiation, SM2 invasion, size >2 cm, LVI, and PDC components in the SM layer were independent risk factors for LNM. When we limited the depth of invasion to SM1, the incidence of LNM was significantly higher in the ≥5 % group. On multivariate analysis, tumor size >2 cm, moderate differentiation, LVI positivity, and ≥5 % PDC components in the SM1 layer were independent risk factors for LNM in SM1 cancer.
  
  
  
  The PDC component in the SM layer of differentiated EGC was an independent risk factor of LNM, which might constitute a supplementary criterion in the expanded indications for endoscopic resection in differentiated EGC.
authors.affiliation: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.|Gangnam Severance Hospital, Seoul, Korea.
authors.forename: Da Hyun
authors.initials: DH
authors.lastname: Jung
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Yoon Sung
authors.initials: YS
authors.lastname: Bae
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sun Och
authors.initials: SO
authors.lastname: Yoon
authors.affiliation: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Yong Chan
authors.initials: YC
authors.lastname: Lee
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hoguen
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Surgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sung Hoon
authors.initials: SH
authors.lastname: Noh
authors.affiliation: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.|Gangnam Severance Hospital, Seoul, Korea.
authors.forename: Hyojin
authors.initials: H
authors.lastname: Park
authors.affiliation: Gangnam Severance Hospital, Seoul, Korea.|Department of Surgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Seung Ho
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea. otilia94@yuhs.ac.|Gangnam Severance Hospital, Seoul, Korea. otilia94@yuhs.ac.
authors.forename: Jie-Hyun
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, Seoul, Korea. kimhyunki@yuhs.ac.
authors.forename: Hyunki
authors.initials: H
authors.lastname: Kim
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology* / Q000601:surgery; D002454:Cell Differentiation; D005260:Female; D005500:Follow-Up Studies; D005743:Gastrectomy; D005753:Gastric Mucosa / Q000473:pathology* / Q000601:surgery; D005773:Gastroscopy; D006801:Humans; D008197:Lymph Node Excision; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011379:Prognosis; D013274:Stomach Neoplasms / Q000473:pathology* / Q000601:surgery