High prostate cancer mortality in Norway: influence of Cancer Registry information?

Norway has among the highest prostate cancer mortality rates in the world. The aim of the present project was to assess whether this can be explained by the unique routine procedure of information transfer from the Cancer Registry of Norway (CR) to the Norwegian Cause of Death Registry (COD Registry). Norwegian prostate cancer patients deceased during 1996 were identified (n=2012). The information basis of the official mortality statistics was reviewed by two physicians, who independently identified the underlying cause of death, primarily prostate cancer or not, supplemented by consensus of two other physicians. The coding was done in two steps; first without, then with CR information. Project physicians identified 1063 deaths from prostate cancer as compared to the official number of 1161, with discrepancy as to prostate cancer death in 126 deceased. Information from the CR increased the project's age-adjusted (world standard population) prostate cancer mortality rate by less than 1% (from 22.7 to 22.9 per 100,000). In conclusion, the high rates of prostate cancer mortality in Norway could not be explained by information transfer from the CR to the COD Registry.