title: Indications for a pylorus-preserving gastrectomy for gastric cancer with proper muscle invasion.
abstract: OBJECTIVE
  Our previous demonstrations of the feasibility of a pylorus-preserving gastrectomy with a wider-scope lymphadenectomy for early gastric cancer (GC) have raised the possibility of applying pylorus-preserving gastrectomy to a broader segment of GC patients, such as those having GC with invasion extending into the proper muscle layer (GCpm).
  
  
  METHODS
  Case series.
  
  
  METHODS
  Tertiary care center.
  
  
  METHODS
  This study comprised 107 patients with solitary primary GCpm located in the middle or lower third of the stomach.
  
  
  METHODS
  All patients underwent gastrectomy, using at least the former D2 dissection of the American Joint Committee on Cancer.
  
  
  METHODS
  Patterns and sites of nodal involvement were analyzed in relationship to other clinicopathologic characteristics, including preoperative and intraoperative evaluations of tumor depth (cT), nodal involvement (cN), and serosal involvement. The conditions required were serosal negativity and measurements less than or equal to cT2 cN0 with histologic proof of node negativity, or if positive, the positive nodes had to be confined to the first or selective second tier. The selective second-tier nodes were defined as those along the left gastric, common hepatic, and celiac arteries.
  
  
  RESULTS
  The factors favoring node negativity were serosal negativity, cN0, or both. For tumors that were serosal-negative and less than or equal to cT2 cN0 to meet the above conditions, a tumor in the middle third of the stomach had to be less than or equal to 2 cm in the maximum diameter, and that in the lower third could be any size. No patients with serosal negativity and cT2 cN0 GCpm less than or equal to 2 cm in diameter died of cancer or had positive nodes beyond the selective second tier.
  
  
  CONCLUSIONS
  Considering the required distance between the pyloric ring and distal margin of the tumor to avoid a positive resection margin, pylorus-preserving gastrectomy with a selective second-tier node dissection is optimal for tumors that are serosal negative, less than or equal to cT2 cN0, and less than or equal to 2 cm in maximum diameter when located in the middle or lower third of the stomach.
authors: Department of Gastrointestinal Surgery, University of Tokyo, Tokyo, Japan. shimoyama-dis@h.u-tokyo.ac.jp
authors: Shouji
authors: S
authors: Shimoyama
authors: Ken-ichi
authors: K
authors: Mafune
authors: Michio
authors: M
authors: Kaminishi
mesh_terms: D000368:Aged; D005260:Female; D005743:Gastrectomy / Q000379:methods*; D006801:Humans; D008197:Lymph Node Excision / Q000379:methods; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D010537:Peritoneum; D013274:Stomach Neoplasms / Q000473:pathology* / Q000601:surgery*; D016896:Treatment Outcome