Recognizing Histological Patterns in the Endometrial Scrape Cytology of Hysterectomy Specimens

Background: There is an absence of standardized diagnostic criteria for endometrial cytology. Aims: This study aims at recognizing various patterns seen in endometrial scrape cytology from hysterectomy specimens against histopathological features. The dependability of these patterns for accurate cytological diagnosis of endometrial pathology was assessed. Materials and methods: 106 uteri in two separate batches of 50 and 56 received consecutively in surgical pathology laboratory were grossed and their features documented. Each endometrium was scraped by a scalpel, subsequently two H&E and two PAP smears were prepared. Inadequate smears and specimens which were received cut-opened were excluded. The cytological findings were broadly categorized into benign endometrium (including phases of menstrual cycle, endometritis and atrophic endometrium), decidual change, pill endometrium, endometrial hyperplasia, suspicious of malignancy and malignancy. Sensitivity, specificity, likelihood ratio, pre-test odds, post-test odds and diagnostic odds ratio were calculated for hyperplasia/malignancy and only malignancy. Results: The cytological evaluation for endometrial malignancy showed sensitivity, specificity of 66.7% and 99% respectively. The pre-test odds were 3%. For positive results, the likelihood ratio and the post-test odds were 69 and 67% respectively. The likelihood ratio was 0.34 with a post-test odds of 1% for negative results. The diagnostic odds ratio was 204. Conclusions: Endometrial hyperplasia was missed in cytology because the cellularity in comparison to benign endometrium was not different. Enlarged vesicular nuclei with prominent nucleoli were seen on review. One cytologic misdiagnosis of adenocarcinoma as benign endometrium was owing to low cellularity wherein the patterns were not seen