A comparison of endometrial sampling histopathology by Pipelle curette versus Karman cannula in patients with abnormal uterine bleeding at a tertiary care hospital in Northwest Rajasthan

Background: Abnormal uterine bleeding (AUB) is a common and devastating condition affecting women of all ages. Among all patients attending gynecology outpatient department clinic, more than one-third patients are related to AUB, and this proportion rises to 70% in the perimenopausal and postmenopausal age. The condition has a high reported prevalence rate of 17.9% in India. Aims and Objective: To compare endometrial sampling histopathology by Pipelle curette versus Karman cannula in patients with AUB at a tertiary care hospital in Northwest Rajasthan. Materials and Methods: It was a prospective study conducted on 100 female patients of all age groups attending the department of obstetrics and gynecology over a period of 1 year with clinical diagnosis of AUB. After detailed history, examination, and relevant investigations, each patient was subjected first to endometrial aspiration using Pipelle curette followed by endometrial aspiration using Karman cannula No. 4. Samples collected were sent for histopathological assessment and the results were compared. Results: In our study, in 84% of cases, samples obtained by both Pipelle curette and Karman cannula were adequate. In 5% of cases, samples were inadequate by both methods. In 10% of cases, Karman cannula sample was adequate, but Pipelle curette sample was inadequate. In 1% of cases, sample could not be obtained by both procedures due to stenosed nulliparous cervix with large fibroid obstructing cervical os. Considering Karman cannula as the standard, Pipelle curette endometrial sampling demonstrated 100% sensitivity, specificity, positive and negative predictive value (PPV and NPV), and accuracy with regard to diagnosis of adenocarcinoma and endometrial hyperplasia. For secretory endometrium, the corresponding values were 76.5%, 100%, 100%, 95.4%, and 99%, respectively. With regard to proliferative endometrium, sensitivity, specificity, PPV, NPV, and accuracy were 92%, 96%, 98.6%, 80%, and 93%, respectively. With regard to atrophic endometrium, specificity, NPV, and accuracy were 100%, 99%, and 99%, respectively. Pipelle curette had a concordance rate of 87.5% with hysterectomy specimen, while Karman cannula had a concordance rate of 100%. Conclusion: Both Pipelle curette and Karman cannula endometrial aspiration biopsy are easy to perform, efficient, and safe outpatient endometrial sampling procedure in recognizing the endometrial lesions including malignancy and endometrial hyperplasia; however, Karman cannula had more adequate sample than Pipelle curette.