Ovarian cancer in Switzerland: incidence and treatment according to hospital registry data

Abstract

The methods used to diagnose and classify ovarian cancer have changed over the past decade. We used hospital registry data to assess the incidence, treatment durations and hospital costs of ovarian cancer in Switzerland. We carried out a retrospective analysis of a hospital registry covering all inpatient care episodes in Switzerland between 1998 and 2012. Ovarian cancer incidence was assessed by identifying patients with a first ovarian cancer diagnosis as the main reason for hospital stay after an event-free period. We assessed the duration and cost of ovarian cancer treatment sequences as well as the evolution of hospital patient volume over time. The average age-adjusted incidence rate was 14.6 per 100,000 women per year between 2004 and 2012. This rate is substantially higher (+35.5%) than the corresponding rate published by the National Institute for Cancer Epidemiology and Registration (NICER). Hospital patient volume was low in most cases, with more than 40% of patients treated in hospitals with fewer than 20 cases per year. However, the share of patients treated in hospitals with more than 30 cases per year has increased substantially since 2009. We found a substantial difference between the ovarian cancer incidence estimate based on hospital registry data and the corresponding estimate by NICER. The reasons for this substantial difference should be carefully explored. A case-wise comparison could determine whether the difference is due to over- or under-reporting in one of the two registries. The low ovarian cancer patient volume in many hospitals is in conflict with the numbers required for certified specialised cancer centres. The recent increase in patient volume in specialised cancer centres, however, might reflect a growing understanding of the needs and requirements of comprehensive cancer care.