Active observation versus interval appendicectomy after successful non-operative treatment of an appendix mass in children (CHINA study): an open-label, randomised controlled trial.

BACKGROUND: Despite a scarcity of supporting evidence, most surgeons recommend routine interval appendicectomy after successful non-operative treatment of an appendix mass in children. We aimed to compare routine interval appendicectomy with active observation.

METHODS: We enrolled participants in the CHildren's INterval Appendicectomy (CHINA) study, a multicentre, open-label, randomised controlled study at 19 specialist paediatric surgery centres, 17 of which were in the UK, one in Sweden, and one in New Zealand. 106 children aged 3-15 years were assigned (1:1) by weighted minimisation to interval appendicectomy or active observation with minimisation for age, trial centre, sex, and presence of a faecolith on imaging. Eligible children had acute appendicitis with an appendix mass and were successfully treated without appendicectomy or other surgical intervention. Children were excluded from the study if they had coexisting gastrointestinal disease or had a substantial coexisting medical condition or immune defect. Because of the nature of the interventions, blinding was not possible. The primary outcome was the proportion of children developing histologically proven recurrent acute appendicitis or a clinical diagnosis of recurrent appendix mass within 1 year of enrolment after successful non-operative treatment of appendix mass (active observation group) and incidence of severe complications related to interval appendicectomy. Data were analysed on an intention-to-treat basis. This study is registered with ISRCTN, number 93815412.

FINDINGS: Between Aug 8, 2011, and Dec 31, 2014, we randomly assigned 106 patients, 52 patients to interval appendicectomy and 54 to active observation. Two children in the interval appendicectomy group were withdrawn due to withdrawal of consent; two in the active observation group were withdrawn because they became ineligible after allocation. Six children under active observation had histologically proven recurrent acute appendicitis. Three children in the interval appendicectomy group had severe complications. Thus, the proportion of children with histologically proven recurrent acute appendicitis under active observation was 12% (95% CI 5-23) and the proportion of children with severe complications related to interval appendicectomy was 6% (95% CI 1-17).

INTERPRETATION: More than three-quarters of children could avoid appendicectomy during early follow-up after successful non-operative treatment of an appendix mass. Although the risk of complications after interval appendicectomy is low, complications can be severe. Adoption of a wait-and-see approach, reserving appendicectomy for those who develop recurrence or recurrent symptoms, results in fewer days in hospital, fewer days away from normal daily activity, and is cheaper than routine interval appendicectomy. These high-quality data will allow clinicians, parents, and children to make an evidence-based decision regarding the justification for interval appendicectomy.

FUNDING: BUPA Foundation.