title: Tumor volume successively reflects the state of disease progression in endometrial cancer.
abstract: OBJECTIVE
  This study aimed to clarify the clinical significance of tumor volume in endometrial cancer.
  
  
  METHODS
  A total of 667 patients with endometrial cancer who underwent preoperative MRI and surgical treatment including lymphadenectomy were enrolled. As the surrogate marker of actual tumor volume, the volume index was defined as the product of the maximum longitudinal diameter along the uterine axis, the maximum intersecting anteroposterior diameter of the sagittal section image, and the maximum horizontal diameter of the horizontal section image from the MRI data. The volume index was divided into five categories: Group 1 (<8), Group 2 (8 to <27), Group 3 (27 to <64), Group 4 (64 to <125), and Group 5 (125 or more). The relationships between various clinicopathologic factors and volume index were investigated, and Cox regression analysis was conducted to assess the significance of volume index with respect to prognosis.
  
  
  RESULTS
  High-risk clinicopathologic findings increased with tumor volume. The lymph node metastasis rate was 3% in Group 1, 9% in Group 2, 17% in Group 3, 25% in Group 4, and 53% in Group 5. Cox regression analysis showed that the volume index (≥36) was a prognostic factor (hazard ratio: 2.0, 95% confidence interval: 1.3-3.1) independent of older age (≥58 years), high-risk histological grade/subtype, deep myoinvasion, lymph node metastasis, and type of surgery.
  
  
  CONCLUSIONS
  Tumor volume successively reflects the state of disease progression in endometrial cancer. The volume index can give information on both the staged prognosis and surgical management.
authors.affiliation: Division of Gynecologic Oncology, National Hospital Organization, Hokkaido Cancer Center, 4-2 Kikusui, Shiroishi-ku, Sapporo, Japan. yukiharu@sap-cc.go.jp
authors.forename: Yukiharu
authors.initials: Y
authors.lastname: Todo
authors.forename: Hidemichi
authors.initials: H
authors.lastname: Watari
authors.forename: Kazuhira
authors.initials: K
authors.lastname: Okamoto
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Hareyama
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Minobe
authors.forename: Hidenori
authors.initials: H
authors.lastname: Kato
authors.forename: Noriaki
authors.initials: N
authors.lastname: Sakuragi
mesh_terms: D018450:Disease Progression; D016889:Endometrial Neoplasms / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D016019:Survival Analysis