Purpose: Mucinous appendiceal tumours were described already 180 years ago, but reliable data on the incidence of these tumours are sparse. The clinical importance of these tumours is increasing since they are now identified as the most common site of origin for pseudomyxoma peritonei (PMP), which is currently recognised as a treatable condition.
Methods: Data on the incidence of mucinous appendiceal tumours were retrieved from the Eindhoven Cancer Registry, which collects data on all patients with newly diagnosed cancer in a large part of the southern Netherlands that comprises about 2.3 million inhabitants. From 1980 to 2010, all cases of primary adenocarcinomas of the appendix were included.
Results: From 1980 to 2010, a mucinous adenocarcinoma was diagnosed in 78 patients being 48 % of all cases of appendiceal adenocarcinoma diagnosed during this period (n = 164). The incidence increased during the study period from 0.6 to 1.9 per 1,000,000 person-years for women and from 0.4 to 1.0 per 1,000,000 person-years for men.
Conclusion: The reported incidence of mucinous adenocarcinomas of the appendix shows an increasing trend. This is probably mainly explained by the increased awareness of this tumour and its relation with PMP, and better registration of this specific diagnosis.