Risk of Appendiceal Malignancy in Conservatively Treated Acute Appendicitis

Purpose/Background: Appendectomy is the standard treatment of acute appendicitis (AA) but conservative treatment has gained success. The need for follow-up after conservatively treated AA is unclear. Hypothesis/Aim: This study evaluates follow-up, recurrence and appendiceal malignancy in conservatively treated AA. Methods/Interventions: This retrospective study included patients with conservatively treated AA at Skåne University Hospital, Sweden during 2012-2019. Information on patient demographics at index admission and data on follow-up, recurrences and later appendectomies were retrieved from medical charts. Results/Outcome(s): The study cohort included 391 patients, 152 with uncomplicated and 259 with complicated AA. Median time of follow-up was 45 months. The recurrence rate was lower after uncomplicated AA (13.8%) than for complicated AA (22.2%; p= 0.049). During follow-up 52 (21.8%) of patients with complicated AA underwent appendectomy. Appendiceal malignancies were found in 12 (5%) patients with previous complicated vs no appendiceal malignancies after uncomplicated AA (p= 0.001). Limitations: This study was limited by its retrospective design, the high rate of excluded patients and the variation of follow-up time from index admission to data collection. Conclusions/Discussion: The relatively low incidence of appendiceal malignancies in this study does not support routine interval appendectomy in patients after complicated AA. Evidence regarding follow-up after conservatively treated AA is scarce and needs to be evaluated according to standardised protocols