This prospective study was performed to investigate epidemiological characteristics in terms of the age- and sex-specific incidence in patients with perforated and nonperforated appendicitis. The study population comprised 1486 consecutive patients who underwent appendectomy for suspected acute appendicitis between 1989 and 1993. Two patient cohorts [n = 544 (37%)] were analyzed with regard to prehospitalization duration of symptoms and in-hospital observation time. The crude incidence of acute appendicitis was 86 per 100,000 per year. Although the incidence of nonperforated appendicitis was highest among adolescents and young adults (13-40 years of age), perforated appendicitis occurred at almost the same incidence in all sex and age groups. The diagnostic accuracy was 76%. Perforated appendicitis occurred in 19%, with higher rates in small children and the elderly, irrespective of gender. A high diagnostic accuracy was not associated with an increased rate of perforation. In small children and the elderly, the diagnostic accuracy was low and the perforation rate high. Patients with perforation had a significantly longer duration of symptoms as well as in-hospital observation time than did patients with nonperforated appendicitis. Perforated appendicitis showed a different incidence pattern than nonperforated appendicitis and was associated with a significantly longer duration of symptoms and in-hospital observation time, probably due to patient-related factors. We suggest this observation deserves attention regarding clinical diagnosis and treatment decision-making for patients with suspected acute appendicitis.

Background: Transanal total mesorectal excision (TaTME) for rectal cancer has emerged as an alternative to the traditional abdominal approach. However, concerns have been raised about local recurrence. The aim of this study was to evaluate local recurrence after TaTME. Secondary aims included postoperative mortality, anastomotic leak and stoma rates. Methods: Data on all patients who underwent TaTME were recorded and compared with those from national cohorts in the Norwegian Colorectal Cancer Registry (NCCR) and the Norwegian Registry for Gastrointestinal Surgery (NoRGast). Kaplan-Meier estimates were used to compare local recurrence. Results: In Norway, 157 patients underwent TaTME for rectal cancer between October 2014 and October 2018. Three of seven hospitals abandoned TaTME after a total of five procedures. The local recurrence rate was 12 of 157 (7⋅6 per cent); eight local recurrences were multifocal or extensive. The estimated local recurrence rate at 2⋅4 years was 11⋅6 (95 per cent c.i. 6⋅6 to 19⋅9) per cent after TaTME compared with 2⋅4 (1⋅4 to 4⋅3) per cent in the NCCR (P < 0⋅001). The adjusted hazard ratio was 6⋅71 (95 per cent c.i. 2⋅94 to 15⋅32). Anastomotic leaks resulting in reoperation occurred in 8⋅4 per cent of patients in the TaTME cohort compared with 4⋅5 per cent in NoRGast (P = 0⋅047). Fifty-six patients (35⋅7 per cent) had a stoma at latest follow-up; 39 (24⋅8 per cent) were permanent.Conclusion: Anastomotic leak rates after TaTME were higher than national rates; local recurrence rates and growth patterns were unfavourable.

Conclusion:Research on colorectal cancer needs to be stratified according to microsatellite status in order further to explore the molecular mechanisms and clinicopathological consequences of MSI.

clinicaltrials.gov Identifier: NCT01047462.