Acute Appendicitis Secondary to Metastatic Malignancy - A Review of 78 Cases in Literature

Abstract

Background: Acute appendicitis is one of the most common causes of acute abdomen presentation to the emergency department. Appendicectomy is one of the most common emergency operations performed. Appendicitis is attributed to lymphoid hyperplasia or faecolith causing obstruction of the appendiceal lumen. Other causes include helminth infection, primary appendiceal tumours, malignancy, and calculi. Metastatic malignancy causing acute appendicitis is very uncommon. In this article, we review the literature that exists reporting acute appendicitis attributed to metastatic diseases of the appendix, the malignancies that were identified, and the nature of the presentation. Methods:This study was performed following the Scale for the Assessment of Narrative Review Articles (SANRA). A literature review of existing case reports, abstracts, and studies was performed. PubMed and Google Scholar were used to search for the articles. Several cases were identified using the 'snowball method' where references were used to identify additional published literature.Results: Seventy-eight cases of acute appendicitis secondary to metastatic malignancies were identified. The most commonly reported metastatic malignancy causing appendicitis were breast, lung, gastric, and prostate. There was a total of n=34 (46%) of individuals with complicated appendicitis, n=40 (54%) with uncomplicated appendicitis, and four cases did not have degree of inflammation documented. The mean age of the patients was 57 years old. Conclusion:Appendicitis secondary to metastatic disease is a rare entity. This literature review has collated data identifying known primary malignancies that are associated with metastatic disease to the appendix. The most common have been identified as breast, lung, gastric and prostate primary malignancies. The mean age of patients in this review is 57. Patients presented with more complicated disease in comparison to the general population with acute appendicitis without malignancy. While rare, it important to be cognizant to the patient's previous malignancies even after the surveillance period has been completed. In this article we review the literature that exists reporting acute appendicitis attributed to secondary metastatic disease of the appendix, the malignancies that were identified and the nature of the presentation. When considering management of appendicitis, it is important to be cognizant as to whether the patient has had previous malignancies even after the surveillance period is over.