Appendiceal neoplasms in Saudi Arabia: prevalence and clinicopathological profile.

Background: The appendix is a small organ with no particular known function. Primary appendiceal neoplasms (ANs) are rare. While the prevalence is increasing worldwide over the past two decades, no apparent increase in the prevalence of ANs has been reported in the Arabian Gulf States. Recently, a significant decline in the age at diagnosis of some types of ANs has been reported worldwide, with a female predominance.

Objectives: Evaluate the prevalence and clinicopathological characteristics of ANs within our institution in Saudi Arabia and compare them to limited existing studies from different regions as well as the Arabian Gulf States.

Design: Retrospective cohort.

Setting: Tertiary care center in Riyadh.

Patients and methods: All patients who underwent appendectomy and had the appendix submitted for histopathological evaluation between May 2015 and June 2020 were included to allow for a follow-up of 5 years or more at the time of data collection.

Main outcome measures: Demographics, clinical presentations, surgical interventions, histopathological findings, complications, and recurrence rates.

Sample size: 25 AN patients.

Results: Of 1110 patients, 25 had ANs (13 female and 12 male participants) with a mean (standard deviation) age of 54.6 (14.1) years. Only 40% presented with acute appendicitis, 64% had comorbidities, and less than 50% underwent laparoscopic appendectomy. Histopathologically, 72% were low-grade appendiceal mucinous neoplasms (LAMNs). Complications were minimal grades (Clavien-Dindo classification), with 80% experiencing none. The mean hospital stay was 9.96 days. Local recurrence occurred in 8% of cases, and distant metastasis was documented in one adenocarcinoma case. However, the 5-year overall and disease-free survival rates were 88% and 80%, respectively.

Conclusions: The incidence of ANs is increasing in Saudi Arabia with the higher prevalence of LAMNs. The pathological examination of the resected appendix played a pivotal role in the diagnosis of ANs.

Limitations: Data collected retrospectively, a single institution, and a small population.