Does the presence of single compared to multiple endometrial polyps alter the risk of cancer in post-menopausal women?

Abstract

OBJECTIVE: To evaluate the relative rates of malignancy in women with single and multiple polyps presenting to a UK Cancer Centre with postmenopausal bleeding (PMB). STUDY DESIGN: A retrospective review of patients treated at Royal Derby Hospital (RDH) for PMB who underwent outpatient hysteroscopy based on ultrasonographic suspicion of endometrial polyps between May 2014 to December 2019. The main outcome measure was the rates of precancerous and malignant histology for single or multiple polyps. The secondary outcomes assessed the influence of risk factors on the rates of malignancy within the single and multiple polyps groups. RESULTS: The study population was 851 women of which 533 were in the single polyp group and 318 in the multiple polyps group. The multiple polyps group (mean age 65.2 years) was older compared to the single polyp group (mean age 62.1 years), P = 0.0001. Elevated rates of cancer was driven most significantly by endometrioid cancer in the multiple polyps compared to single polyp group, with rates of 50/314 (16 %) and 28/512 (5.5 %) respectively, P=< 0.00001. For rarer histologies there was no significant difference between the proportion of serous, carcinosarcomas and clear cell cancers between those with single compared to multiple polyps (P > 0.05). Significantly more endometrial hyperplasia with atypia (AEH) was found in the multiple polyps compared to single polyp group, with rates of 18/314 (5.7 %) and 15/512 (2.9 %) respectively, P = 0.046. CONCLUSION: Our study found increased rates of endometrioid cancer and its precursor, AEH within the multiple polyps compared to the single polyps groups. Future risk predicting algorithms should consider incorporating single and multiple polyps as part of their risk model.