Prostate cancer registration in four Swedish regions 1996-- differences in incidence, age structure and management

In 1996 registration of prostate cancer in four of the six Swedish regions was started to facilitate evaluation of geographical variations in incidence and treatment.

For all cases of prostate cancer, personal identification number, tumour stage, tumour grade and primary treatment were registered.

In the four regions covered by the register, 3541 cases of prostate cancer were registered. Altogether there were 5795 cases of prostate cancer diagnosed in Sweden the same year. The age-standardized incidence varied from 89/100000 to 169/100000 among counties. The proportion of localized tumours correlated positively to the incidence (p < 0.05) and negatively to mean age at diagnosis (p < 0.01). There was also a significant positive correlation between the proportion of localized tumours and the percentage of patients given curative treatment. All registered variables showed large geographical variations, especially concerning percentage of T1c tumours, treatment of localized tumours and choice of palliative treatment.

Diagnostic activity varied considerably among counties, resulting in large variation in age-standardized incidence. High incidence is associated with a larger proportion of localized tumours, which, in turn, is associated with early age at diagnosis. In counties where a policy of detecting tumours early is practised, curative treatment is also given more often. Treatment of localized tumours and preference for palliative treatment seem to depend on local traditions. The lack of cytological and histopathological standards makes geographical comparisons based on tumour grade impossible.