title: Assessment of endometrial sampling as a predictor of final surgical pathology in endometrial cancer.
abstract: BACKGROUND
  The histology and grade of endometrial cancer are important predictors of disease outcome and of the likelihood of nodal involvement. In most centres, however, surgical staging decisions are based on a preoperative biopsy. The objective of this study was to assess the concordance between the preoperative histology and that of the hysterectomy specimen in endometrial cancer.
  
  
  METHODS
  Patients treated for endometrial cancer during a 10-year period at a tertiary cancer centre were identified from a prospectively collected pathological database. All pathology reports were reviewed to confirm centralised reporting of the original sampling or biopsy specimens; patients whose biopsies were not reviewed by a dedicated gynaecological pathologist at the treating centre were excluded. Surgical pathology data including histology, grade, depth of myometrial invasion, cervical stromal involvement and lymphovascular space invasion (LVSI) as well as preoperative histology and grade were collected. Preoperative and final tumour cell type and grade were compared and the distribution of other high-risk features was analysed.
  
  
  RESULTS
  A total of 1329 consecutive patients were identified; 653 patients had a centrally reviewed epithelial endometrial cancer on their original biopsy, and are included in this study. Of 255 patients whose biopsies were read as grade 1 (G1) adenocarcinoma, 45 (18%) were upgraded to grade 2 (G2) on final pathology, 6 (2%) were upgraded to grade 3 (G3) and 5 (2%) were read as a non-endometrioid high-grade histology. Overall, of 255 tumours classified as G1 endometrioid cancers on biopsy, 74 (29%) were either found to be low-grade (G1-2) tumours with deep myometrial invasion, or were reclassified as high-grade cancers (G3 or non-endometrioid histologies) on final surgical pathology. Despite these shifts, we calculate that omitting surgical staging in preoperatively diagnosed G1 endometrioid cancers without deep myometrial invasion would result in missing nodal involvement in only 1% of cases.
  
  
  CONCLUSIONS
  Preoperative endometrial sampling is only a modest predictor of surgical pathology features in endometrial cancer and may underestimate the risk of disease spread and recurrence. In spite of frequent shifts in postoperative vs preoperative histological assessment, the predicted rate of missed nodal metastases with a selective staging policy remains low.
authors.affiliation: Department of Gynecologic Oncology, Chaim Sheba Medical Center, Ramat Gan, 5262000, Israel.
authors.forename: L
authors.initials: L
authors.lastname: Helpman
authors.affiliation: 1] Sunnybrook Health Sciences Center, Toronto, Ontario, Canada M4N 3M5 [2] Department of Gynecologic Oncology, University of Toronto, 27 King's College Circle, Toronto, Ontario, Canada M5S 1A1.
authors.forename: R
authors.initials: R
authors.lastname: Kupets
authors.affiliation: 1] Sunnybrook Health Sciences Center, Toronto, Ontario, Canada M4N 3M5 [2] Department of Gynecologic Oncology, University of Toronto, 27 King's College Circle, Toronto, Ontario, Canada M5S 1A1.
authors.forename: A
authors.initials: A
authors.lastname: Covens
authors.affiliation: 1] Sunnybrook Health Sciences Center, Toronto, Ontario, Canada M4N 3M5 [2] Department of Laboratory Medicine and Pathobiology, University of Toronto, 27 King's College Circle, Toronto, Ontario, Canada M5S 1A1.
authors.forename: R S
authors.initials: RS
authors.lastname: Saad
authors.affiliation: 1] Sunnybrook Health Sciences Center, Toronto, Ontario, Canada M4N 3M5 [2] Department of Laboratory Medicine and Pathobiology, University of Toronto, 27 King's College Circle, Toronto, Ontario, Canada M5S 1A1.
authors.forename: M A
authors.initials: MA
authors.lastname: Khalifa
authors.affiliation: 1] Sunnybrook Health Sciences Center, Toronto, Ontario, Canada M4N 3M5 [2] Department of Laboratory Medicine and Pathobiology, University of Toronto, 27 King's College Circle, Toronto, Ontario, Canada M5S 1A1.
authors.forename: N
authors.initials: N
authors.lastname: Ismiil
authors.affiliation: 1] Sunnybrook Health Sciences Center, Toronto, Ontario, Canada M4N 3M5 [2] Department of Laboratory Medicine and Pathobiology, University of Toronto, 27 King's College Circle, Toronto, Ontario, Canada M5S 1A1.
authors.forename: Z
authors.initials: Z
authors.lastname: Ghorab
authors.affiliation: 1] Sunnybrook Health Sciences Center, Toronto, Ontario, Canada M4N 3M5 [2] Department of Laboratory Medicine and Pathobiology, University of Toronto, 27 King's College Circle, Toronto, Ontario, Canada M5S 1A1.
authors.forename: V
authors.initials: V
authors.lastname: Dubé
authors.affiliation: 1] Sunnybrook Health Sciences Center, Toronto, Ontario, Canada M4N 3M5 [2] Department of Laboratory Medicine and Pathobiology, University of Toronto, 27 King's College Circle, Toronto, Ontario, Canada M5S 1A1.
authors.forename: S
authors.initials: S
authors.lastname: Nofech-Mozes
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D016889:Endometrial Neoplasms / Q000473:pathology* / Q000601:surgery*; D005260:Female; D006801:Humans; D007044:Hysterectomy; D008207:Lymphatic Metastasis / Q000473:pathology*; D008875:Middle Aged; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000473:pathology / Q000601:surgery; D010340:Pathology, Surgical; D011300:Preoperative Care