Routine interval appendectomy is unnecessary after conservative treatment of appendiceal mass

The traditional management of appendiceal mass is initial conservative treatment followed by interval appendicectomy. Recently interval appendicectomy has been questioned by a growing amount of evidence. The purpose of this study was to clarify the role of interval appendicectomy after successful initial conservative treatment.

The study included 98 patients with a mass in the right iliac fossa. Four (4%) patients were excluded wing to another diagnosis of appendiceal mass including caecal cancer (two), diverticulitis (one), and Crohn's disease (one). The remaining 94 patients were treated conservatively. Routine interval appendicectomy was not performed after successful conservative treatment.

Ultrasound (US)-guided drainage was performed in seven (7.4%) patients. Two were drained surgically because of a persistent abscess despite a previous US-guided drainage. In five (5.3%) patients, a delayed operation was necessary because of complications. One patient developed small bowel obstruction, and in three patients, conservative treatment was unsuccessful with the abscess remaining unresolved. Within 3 months, seven out of the 89 patients were readmitted to hospital with a recurrent mass in two patients and acute appendicitis without a mass in five patients. Six (6.7%) patients were readmitted with recurrent appendicitis after 3 months. The recurrence rate after successful conservative treatment was 14.6%. The majority (nine patients; 10.1%) of the recurrences occurred within the first 6 months, and after 1 year the recurrence rate was very low (two patients; 2.2%).

Routine interval appendicectomy after initial successful conservative treatment is not justified and should be abandoned. At present, there is no consensus for the management of appendiceal mass. There is, therefore, a need to develop a protocol for the management of this common problem.