Stage-specific mortality and survival trends of prostate cancer patients in Finland before and after introduction of PSA.

BACKGROUND

The early diagnosis and right treatment strategy of localized prostate cancer (PCa) remains problematic. In order to characterize the survival of PCa patients, we compared patients' all-cause and cancer-specific mortalities between pre- and post-PSA periods by stage in Finland.

MATERIAL AND METHODS

All PCa cases diagnosed in Finland between 1985 and 2013 (N = 91,329) were identified from the Finnish Cancer Registry (FCR). PCa stage at diagnosis was defined as localized, local node positive or metastasized. Standardized mortality ratios (SMRs), and relative and cause-specific survival were assessed by stage and introduction of PSA testing. The main limitation was the high proportion of men with unknown stage (28%).

RESULTS

A clear decreasing trend in the SMR of PCa patients was evident when pre- and post-PSA eras were compared: for localized PCa, the SMR was 1.43 (95%CI 1.38-1.48) in 1985-1989 and 0.98 (95%CI 0.95-1.01) in 2000-2004, and for metastasized PCa, the SMRs were 4.51 (95%CI 4.30-4.72) and 3.01 (95%CI 2.89-3.12), respectively. Difference between cause-specific and relative survival was pronounced in localized PCa in post-PSA period: 10-year relative survival was 94.6% (95%CI 91.4-97.8) and cause-specific 84.2% (95%CI 82.9-85.5%). In metastasized PCa the difference was not that significant.

CONCLUSIONS

From 1985 to 2009, the SMR among men diagnosed with PCa decreased significantly in Finland. Among men with localized PCa, the SMR decreased even below that of the Finnish male population. This and the increased difference between relative and cause-specific survival reflects most likely selection of men to opportunistic PSA testing. The results highlight the importance of caution in the use of PSA testing in healthy men.