AB211. SOH25_AB_392. Incidence of neoplasms in appendix specimens across a 5-year span—a multi-centre power study

Background: A population sample of approximately 4,000 appendix specimens was analysed across a 5-year span (2019–2023) to assess the incidence of neoplasms. This was then compared to relevant British and American studies done during the 5-year period prior (2013–2018) to create a power study comparing the incidence between the two. The hypothesis being that there is an increasing incidence of appendiceal neoplasms over the past 5 years as compared to the 5 years prior. The null hypothesis being that there is no significant difference between the incidence of neoplasms across the 10 years. We aimed to perform and audit of appendiceal neoplasms.

Methods: Data was collected in three different centres: Midlands Regional Hospital Tallaght, Midlands Regional Hospital Mullingar and Midlands Regional Hospital Portlaoise (MRHT, MRHM, MRHP) covering the Midlands region across the 5-year span. This was collected via a shared Histology platform, and each case was analysed individually. Included in the data was gender, age and diagnosis.

Results: Results showed an increase in incidence of appendiceal neoplasms from 1.9% to 2.1%, a statistically significant (P value) finding. The gender and age most commonly affected remained generally consistent across British, American and Irish databases. There was slight variation in the types of most commonly presenting neoplasms.

Conclusions: This study rejects the null hypothesis that there is no statistically significant increase in incidence of neoplasms in appendix specimens and accepts the hypothesis that there IS an increasing incidence of neoplasms in appendix specimens as compared to prior.

Keywords: Neoplasms; appendix; power study; multicentre; incidence