Influence of department volume on cancer survival for gynaecological cancers--a population-based study in Tyrol, Austria.

Objective: The objective of this study was to assess the effect of department volume on survival of patients with gynaecological cancer.

Methods: We conducted an observational population-based study in Tyrol, Austria. The analysis includes all patient data on incident gynaecological cancer collected by the Cancer Registry of Tyrol. Data were collected since 1988 on a population-based perspective; publication of incidence data since 1988 in Cancer Incidence in Five Continents gives evidence for good completeness and validity of the database. Patient survival status is assessed in a passive way by probabilistic record linkage between incidence data and official mortality data. We applied a multivariate Cox regression with variables age, sex, stage, year of diagnosis, histological verification of diagnosis, transfer to other hospital and department volume. Department volume was categorised in < or = 11/12-23/24-35/ > or = 36 patients per year reflecting one/two/three/more than three patients per month; categories were computed separately for every site we analysed. Departments with up to 11 patients per year were called small departments.

Results: For 4,191 breast cancer patients, we found a negative effect for small departments; hazard ratio (HR) 1.39, 95% confidence interval (CI) 1.22, 1.58. For ovarian cancer patients, we also found a negative effect for small departments (HR 1.27, 95% CI 1.05, 1.54). For cervical cancer patients, we found a positive effect for small departments (HR 0.67, 95% CI 0.51, 0.88). No effect was shown for corpus cancer (HR 0.80, 95% CI 0.63, 1.01).

Conclusion: The results indicate that, in our country, rules on minimum department case-load can further improve survival for breast and ovarian cancer patients.