Endometrial hyperplasia: Emergence of the EIN system

  • V Rajalakshmi
  • Rajeswari Kathiah ESIC Medical College & PGIMSR , Chennai, Tamilnadu, India
  • Meenakshi Sundaram
  • Sathish Selvakumar. A
Keywords: Endometrial intra epithelial neoplasia, Endometrial hyperplasia, EIN.


Background: The diagnosis of precancerous lesions of the endometrium remains unstandardized because, the existing World Health Organization classification categories do not correspond to distinctive biologic groups and are inadequately supported by reproducible histopathologic criteria. The objective of our study is to simplify the diagnosis of endometrial  hyperplasia, make it more reproducible and stratify patients in to two risk groups instead of four using the recent EIN system.Materials &Methods : All cases diagnosed as endometrial hyperplasia classified according to the WHO system  in patients with abnormal uterine bleeding, during the 3 year period 2014-2016 were reclassified as benign hyperplasia and Endometrial intraepithelial neoplasia according to the EIN system. Results : 38 out of the 46 cases (82.6 %) of simple hyperplasia were reclassified as Benign hyperplasia. 8 out of the 46 cases (17.4%) of simple hyperplasia were reclassified as EIN.1 case of complex hyperplasia without atypia was reclassified as EIN. All the 11 cases of complex hyperplasia with atypia were reclassified as EIN.Conclusions : Application of the criteria for EIN successfully segregates patients into high and low cancer risk subgroups with better reproducibility than WHO classification. DOI: 10.21276/APALM.1026

Author Biography

Rajeswari Kathiah, ESIC Medical College & PGIMSR , Chennai, Tamilnadu, India
Associate Professor, Pathology


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Original Article