title: Risk factors that mitigate the role of paraaortic lymphadenectomy in uterine endometrioid cancer.
abstract: OBJECTIVE
  Paraaortic lymph node (PA) dissemination in endometrial cancer (EC) is uncommon and a systematic infrarenal PA dissection carries morbidity. Our objective was to identify a subgroup of EC patients who may potentially forego PA lymphadenectomy (LND).
  
  
  METHODS
  The study endpoint (PA Metastasis or Recurrence; PAMR) was defined as detection of metastasis to PA nodes (among those with any type of PA LND) or PA recurrence within 2 years (among patients without PA LND or those with negative nodes in the context of an inadequate (<5 nodes) PA LND). Patients with non-endometrioid histology, stage IV disease, synchronous cancers, gross extrauterine or gross adnexal disease, neoadjuvant therapy, or insufficient follow-up were excluded. Multivariable logistic regression analysis identified predictors of PAMR.
  
  
  RESULTS
  Of the 946 patients, PAMR was observed in 4% (36/946). Multivariable analysis identified positive pelvic nodes (odds ratio (OR) 24.2; p<0.001), >50% MI (OR 5.3; p<0.001) and lymphovascular space invasion (LVSI) (OR 3.7; p=0.005) as the only three independent predictors of PAMR. When all three factors were absent (77% of study cohort), the predicted probability of PAMR was 0.6%. If intraoperative frozen section is not available on pelvic lymph nodes and LVSI, omitting PA LND in all patients with ≤ 50% MI would affect 84% (792/946) of the total cohort, with a 1.1% risk of PAMR (9/792).
  
  
  CONCLUSIONS
  The majority of patients with endometrioid EC may potentially forgo PA LND with expected reductions in surgical morbidity and cost. This cohort may be identified by a combined absence of: positive pelvic nodes, >50% MI and LVSI.
authors.affiliation: Division of Gynecologic Surgery, Mayo Clinic, Rochester, MN, USA.
authors.forename: S
authors.initials: S
authors.lastname: Kumar
authors.forename: A
authors.initials: A
authors.lastname: Mariani
authors.forename: J N
authors.initials: JN
authors.lastname: Bakkum-Gamez
authors.forename: A L
authors.initials: AL
authors.lastname: Weaver
authors.forename: M E
authors.initials: ME
authors.lastname: McGree
authors.forename: G L
authors.initials: GL
authors.lastname: Keeney
authors.forename: W A
authors.initials: WA
authors.lastname: Cliby
authors.forename: K C
authors.initials: KC
authors.lastname: Podratz
authors.forename: S C
authors.initials: SC
authors.lastname: Dowdy
mesh_terms: D000368:Aged; D001011:Aorta; D001808:Blood Vessels / Q000473:pathology; D016889:Endometrial Neoplasms / Q000473:pathology* / Q000601:surgery*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology / Q000601:surgery*; D008207:Lymphatic Metastasis; D042601:Lymphatic Vessels / Q000473:pathology; D008875:Middle Aged; D015999:Multivariate Analysis; D009215:Myometrium / Q000473:pathology; D009361:Neoplasm Invasiveness; D016017:Odds Ratio; D010388:Pelvis; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors
keywords: Endometrial cancer; Lymphadenectomy; Lymphovascular space invasion; Myometrial invasion; Paraaortic lymph nodes