Interval appendectomy after conservative treatment of an appendiceal mass

The purpose of this study was to clarify the role of interval appendectomy after conservative treatment of an appendiceal mass.

From January 1998 to December 2003, patients with an appendiceal mass who received conservative treatment at the Taipei Veterans General Hospital were studied retrospectively. Data on demographics, rate of appendicitis recurrence, duration of hospital stay, and complication rate were collected and analyzed.

A total of 165 patients were included (89 males, 76 females). The mean age was 53.6 years (range 7-89 years). The rate of appendicitis recurrence after conservative treatment was 25.5%; most recurred within 6 months after discharge (83.3%). The benefit of preventing recurrence is less than 16% if interval appendectomy is performed 6 weeks after discharge and less than 10% if it is done 12 weeks later. The complication rate of appendectomy performed before or after recurrence was 10% in both groups. The duration of the second hospital stay for patients who underwent interval appendectomy before or after recurrence was 4.43 +/- 3.32 vs. 6.75 +/- 5.73 days (P = 0.023). Of the 165 patients, 17 (10.3%) had their diagnosis changed after survey or surgery, and 5 (3.03%) were found to have colon cancer upon follow-up.

Patients who recovered from conservative treatment of an appendiceal mass should undergo colonoscopy or barium enema to detect any underlying diseases and to rule out coexistent colorectal cancer. Routine interval appendectomy benefits less than 20% of patients.