Appendectomy and the subsequent risk of cancer: A prospective population-based cohort study with long follow-up.

BACKGROUND: The appendix, an organ of immunological and microbiological importance, could be involved in the pathogenesis of cancers, but results are inconclusive. Our objective was to assess the association between appendectomy and the subsequent risk of cancer. METHODS: Data were obtained from the Rotterdam Study; a long-term prospective population-based study of individuals aged 55 years and older, of which the first cohort started in 1990 and included 7983 participants. Information on appendectomy was obtained through either medical interview at baseline or linkage with the national automated pathology center (PALGA). Cancer cases were pathology based. End of follow-up was January 1st, 2015. The association between appendectomy and risk of cancer was assessed using Cox proportional hazard models, adjusted for known confounders. RESULTS: Of 7135 included participants, 1373 (19.2%) had undergone an appendectomy and 1632 individuals developed cancer. After adjustment for age, sex, socioeconomic status, BMI, smoking, prevalent diabetes mellitus and alcohol intake, a history of appendectomy was associated with a significantly lower risk of cancer [hazard ratio (HR) 0.86, 95% confidence interval (CI) 0.75-0.98]. Subgroup analyses showed similar results for gastrointestinal cancer (HR 0.75, 95% CI 0.56-0.99), in particular colon cancer (HR 0.65, 95% 0.43-0.97), and cancer of the female reproductive organs (HR 0.35, 95% CI 0.15-0.80). CONCLUSION: Participants who underwent an appendectomy had a reduced risk of cancer in general after adjustment for potential confounders. Therefore, these results contradict earlier studies suggestive of an increased risk. Further research is necessary to replicate these results and reveal its underlying mechanism.

Interobserver variability in the classification of appendicitis during laparoscopy.

BACKGROUND: The intraoperative classification of appendicitis dictates the patient's postoperative management. Prolonged antibiotic prophylaxis is recommended for complex appendicitis (gangrenous, perforated, abscess), whereas preoperative prophylaxis suffices for simple appendicitis. Distinguishing these two conditions can be challenging. The aim of this study was to assess interobserver variability in the classification of appendicitis during laparoscopy. METHODS: Short video recordings taken during laparoscopy for suspected appendicitis were shown to surgeons and surgical residents. They were asked to: classify the appendix as indicative of no, simple or complex appendicitis; categorize the appendix as normal, phlegmonous, gangrenous, perforated and/or abscess; and decide whether they would prescribe postoperative antibiotics. Inter-rater reliability was evaluated using Fleiss' κ score and the S* statistic. RESULTS: Some 80 assessors participated in the study. Video recordings of 20 patients were used. Interobserver agreement was minimal for both the classification of appendicitis (κ score 0·398, 95 per cent c.i. 0·385 to 0·410) and the decision to prescribe postoperative antibiotic treatment (κ score 0·378, 0·362 to 0·393). Agreement was slightly higher when published criteria were applied (κ score 0·552, 0·537 to 0·568). CONCLUSION: There is considerable variability in the intraoperative classification of appendicitis and the decision to prescribe postoperative antibiotic treatment.

The impact of disease severity, age and surgical approach on the outcome of acute appendicitis in children.

PURPOSE: Although a national guideline has been implemented, the optimal approach for appendectomy in children remains subject of debate in the Netherlands. Opponents of laparoscopy raise their concerns regarding its use in complex appendicitis as it is reported to be associated with an increased incidence of intra-abdominal abscesses. The aim of this study was to evaluate the outcome of surgical approaches in both simple and complex appendicitis in paediatric patients. METHODS: A 10-year retrospective cohort study was performed (2001-2010) in paediatric patients treated for suspected acute appendicitis. Patients were divided into either simple or complex appendicitis and into different age groups. Primary outcome parameters were complication rate (intra-abdominal abscess (IAA), superficial surgical site infection (SSI) and readmission) and hospital stay. RESULTS: In total, 878 patients have been treated (median age 12, range 0-17 years). Two-thirds of the patients younger than 6 years had complex appendicitis, compared to one quarter in the group aged 13-18. In the complex appendicitis group, LA was associated with more IAA and early readmissions. In the simple appendicitis group, the complication rate was comparable between the two approaches. Significantly more IAAs were seen after LA in the youngest age group. CONCLUSION: This study demonstrates the unfavourable outcome of LA in the youngest age group and in patients with complex appendicitis. Therefore, we advise to treat these patients with an open approach.