Diagnostic Accuracy of Endometrial Aspiration Cytology Compared With Histopathology in Abnormal Uterine Bleeding: A Cross-Sectional Study at a Tertiary Care Hospital.

Introduction Abnormal uterine bleeding (AUB) is a frequent indication for endometrial evaluation. Histopathological examination remains the diagnostic reference standard, but tissue sampling by curettage or biopsy may be invasive and resource-intensive. Endometrial aspiration cytology (EAC) offers a rapid, minimally invasive alternative that can provide an early impression of endometrial pathology. This study assessed the diagnostic performance of EAC against histopathology in women presenting with AUB. Materials and methods This prospective cross-sectional study was conducted from January 2024 to December 2025 in the Department of Pathology, N.K.P. Salve Institute of Medical Sciences & Research Centre and Lata Mangeshkar Hospital, Nagpur, India. Data collection was carried out from May 2024 to August 2025. A total of 100 women with clinically diagnosed AUB were enrolled. Endometrial aspirates were prepared as alcohol-fixed smears and stained with Papanicolaou and hematoxylin and eosin stains. Cytomorphological findings were categorized and correlated with the corresponding histopathological diagnosis. Diagnostic performance was expressed as sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy. Associations with age, bleeding pattern, and ultrasonographic endometrial thickness were assessed statistically. Results The largest age group was 41-50 years, comprising 38 (38%) participants, followed by 31-40 years with 32 (32%). Menorrhagia was the most frequent presentation in 36 (36%) participants. On ultrasonography, 46 (46%) participants had an endometrial thickness of 5-10 mm and 38 (38%) had a thickness greater than 10 mm. Secretory endometrium was the most common cytological diagnosis in 38 (38%) and histopathological diagnosis in 37 (37%), followed by proliferative endometrium in 35 (35%) and 34 (34%), respectively. Histopathology identified simple glandular hyperplasia without atypia in 10 (10%), hyperplasia with atypia in nine (9%), endometrial carcinoma in nine (9%), and granulomatous pathology in one (1%). Cytological findings correlated strongly with histopathology (Pearson chi-square = 132.24, p < 0.001). Postmenopausal bleeding and increasing endometrial thickness were significantly associated with premalignant and malignant pathology. EAC showed a sensitivity of 45/50 (90.0%), specificity of 44/50 (88.0%), PPV of 45/51 (88.2%), NPV of 44/49 (89.8%), and overall diagnostic accuracy of 89/100 (89.0%). Conclusions EAC showed good diagnostic performance and close correlation with histopathology in women with AUB. Its speed, simplicity, and minimally invasive nature make it useful as a screening and preliminary diagnostic procedure, particularly where access to operative sampling is limited. Histopathology remains essential for definitive classification, especially when atypia or malignancy is suspected.