title: Safety and feasibility of minimally invasive gastrectomy during the early introduction in the Netherlands: short-term oncological outcomes comparable to open gastrectomy.
abstract: BACKGROUND
  Minimally invasive techniques for gastric cancer surgery have recently been introduced in the Netherlands, based on a proctoring program. The aim of this population-based cohort study was to evaluate the short-term oncological outcomes of minimally invasive gastrectomy (MIG) during its introduction in the Netherlands.
  
  
  METHODS
  The Netherlands Cancer Registry identified all patients with gastric adenocarcinoma who underwent gastrectomy with curative intent between 2010 and 2014. Multivariable analysis was performed to compare MIG and open gastrectomy (OG) on lymph node yield (≥15), R0 resection rate, and 1-year overall survival. The pooled learning curve per center of MIG was evaluated by groups of five subsequent procedures.
  
  
  RESULTS
  Between 2010 and 2014, a total of 277 (14%) patients underwent MIG and 1633 (86%) patients underwent OG. During this period, the use of MIG and neoadjuvant chemotherapy increased from 4% to 39% (p < 0.001) and from 47% to 62% (p < 0.001), respectively. The median lymph node yield increased from 12 to 20 (p < 0.001), and the R0 resection rate remained stable, from 86% to 91% (p = 0.080). MIG and OG had a comparable lymph node yield (OR, 1.01; 95% CI, 0.75-1.36), R0 resection rate (OR, 0.86; 95% CI, 0.54-1.37), and 1-year overall survival (HR, 0.99; 95% CI, 0.75-1.32). A pooled learning curve of ten procedures was demonstrated for MIG, after which the conversion rate (13%-2%; p = 0.001) and lymph node yield were at a desired level (18-21; p = 0.045).
  
  
  CONCLUSIONS
  With a proctoring program, the introduction of minimally invasive gastrectomy in Western countries is feasible and can be performed safely.
authors.affiliation: Department of Surgery, University Medical Center Utrecht, G04.228, PO 85500, 3508 GA, Utrecht, The Netherlands.
authors.forename: H J F
authors.initials: HJF
authors.lastname: Brenkman
authors.affiliation: Department of Surgery, University Medical Center Utrecht, G04.228, PO 85500, 3508 GA, Utrecht, The Netherlands.
authors.forename: J P
authors.initials: JP
authors.lastname: Ruurda
authors.affiliation: Netherlands Cancer Registry, Netherlands Comprehensive Cancer Organisation (IKNL), PO 19079, 3501 DB, Utrecht, The Netherlands.
authors.forename: R H A
authors.initials: RHA
authors.lastname: Verhoeven
authors.affiliation: Department of Surgery, University Medical Center Utrecht, G04.228, PO 85500, 3508 GA, Utrecht, The Netherlands. r.vanhillegersberg@umcutrecht.nl.
authors.forename: R
authors.initials: R
authors.lastname: van Hillegersberg
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005240:Feasibility Studies; D005260:Female; D005743:Gastrectomy / Q000009:adverse effects / Q000379:methods*; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000009:adverse effects / Q000379:methods*; D020360:Neoadjuvant Therapy / Q000379:methods; D009426:Netherlands; D012042:Registries; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000473:pathology / Q000601:surgery*; D015996:Survival Rate; D016896:Treatment Outcome
keywords: Gastric cancer; Learning curve; Lymph nodes; Minimally invasive; Survival