Prediction of endometrial carcinoma by subjective EIN diagnosis

• Published in: Modern pathology Vol. 18; no. 3; pp. 324 - 330
• Main Authors: Hecht, Jonathan L., Ince, Tan A., Baak, Jan P.A., Baker, Heather E., Ogden, Maryann W., Mutter, George L.
• Format: Journal Article
• Language: English
• Published: 01.03.2005
• ISSN: 0893-3952; 1530-0285
• DOI: 10.1038/modpathol.3800328

Endometrial intraepithelial neoplasia (EIN) is a precursor to endometrioid endometrial adenocarcinoma characterized by monoclonal growth of mutated cells, a distinctive histopathologic appearance, and 45-fold elevated cancer risk. We have applied EIN diagnostic criteria to 97 successive endometrial biopsies classified as hyperplastic according to WHO criteria and correlated results with computer assisted morphometry (D-score) and clinical cancer outcomes. Three pathologists separately reviewed all cases using EIN criteria (gland area>stromal area, cytologic change in focus of altered architecture, lesion size >1mm, and exclusion of cancer and mimics) to classify cases as EIN or non-EIN. Discordant cases were resolved by a consensus review at a multiheaded scope. Clinical outcomes were obtained in 84 patients from patient visit and pathology records. Diagnoses using EIN criteria were unanimous amongst all 3 pathologists in 75% of cases, and intraobserver-reproducibility was excellent (kappa 0.73-0.90). EIN cases encompassed hyperplasias previously diagnosed as atypical (n=18) or non-atypical (8 complex, 2 simple). Eight follow-up cancers were scattered between hyperplasia types (5/21 atypical, 3/63 non-atypical), but all classified as EIN (8/25) and D-Score ≤1 (8/38). Subjective application of EIN criteria correlates well with objective morphometry and successfully segregates patients into high and low cancer risk subgroups with high reproducibility.