title: Tumor diameter as a predictor of lymphatic dissemination in endometrioid endometrial cancer.
abstract: To assess the utility of tumor diameter (TD) for predicting lymphatic dissemination (LD) and determining need for lymphadenectomy following diagnosis of endometrioid endometrial cancer.
  
  
  
  Patients diagnosed with stage I-III endometrioid endometrial cancer during 2003-2013 who underwent pelvic or para-aortic lymphadenectomy during hysterectomy were studied. Intraoperative predictors of LD included TD, grade, myometrial invasion (MI), age, body mass index, and race/ethnicity. Candidate logistic regression models of LD were evaluated for model fit and predictive power.
  
  
  
  Of 737 cancer patients, 68 (9.2%) were node-positive. Single-variable models with only continuous TD (c-statistic 0.77, 95% CI 0.71-0.83) and dichotomous TD with 50-mm cut-off (TD50; c-statistic 0.73, 95% CI 0.67-0.78) were significantly more predictive than with the standard 20-mm cut-off (c-statistic 0.56, 95% CI 0.53-0.59). Overall, the most important LD predictors were TD50 and MI3rds (three-category form). The best candidate model (c-statistic 0.84, 95% CI 0.80-0.88) suggested odds of LD were five times greater for TD >50mm than ≤50mm (OR 4.91, 95% CI 2.73-8.82) and six and ten times greater for MI >33% to ≤66% (OR, 5.70; 95% CI, 2.25-14.5) and >66% (OR 10.2, 95% CI 4.11-25.4), respectively, than ≤33%. Best-model false-negative (0%) and positive (57.2%) rates demonstrated marked improvement over traditional risk-stratification false-negative (1.5%) and positive (76.2%) rates (c-statistic 0.77, 95% CI 0.72-0.82).
  
  
  
  Tumor diameter is an important predictor of LD. Our risk model, containing modified forms of MI and TD, yielded a lower false-negative rate and can significantly decrease the number of lymphadenectomies performed on low-risk women.
authors.affiliation: Department of Obstetrics and Gynecology, Aurora Sinai Medical Center, Aurora Health Care, Milwaukee, WI, United States. Electronic address: callie.cox.bauer@gmail.com.
authors.forename: Callie M
authors.initials: CM
authors.lastname: Cox Bauer
authors.affiliation: Aurora UW Medical Group, Center for Urban Population, Aurora Sinai Medical Center, Aurora Health Care, Milwaukee, WI, United States.
authors.forename: Danielle M
authors.initials: DM
authors.lastname: Greer
authors.affiliation: Aurora UW Medical Group, Center for Urban Population, Aurora Sinai Medical Center, Aurora Health Care, Milwaukee, WI, United States.
authors.forename: Jessica J F
authors.initials: JJF
authors.lastname: Kram
authors.affiliation: Department of Oncology, Aurora St. Luke''s Medical Center, Aurora Health Care, Milwaukee, WI, United States.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Kamelle
mesh_terms: D018269:Carcinoma, Endometrioid / Q000473:pathology* / Q000601:surgery; 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; D008875:Middle Aged; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012307:Risk Factors
keywords: Endometrial cancer; Endometrioid; Lymphatic dissemination; Myometrial invasion; Nodal metastatic disease; Tumor cell grade; Tumor diameter