Problems in Cancer Surveillance: Delineating In Situ and Invasive Bladder Cancer

In this issue of the Journal, Lynch et al (7) describe the im-plications of combining in situ and invasive bladder cancers for reporting purposes by the Surveillance, Epidemiology, and End Results (SEER) Program based at the National Cancer Institute. They discuss the implications of this practice in regard to the importance ascribed to bladder cancer relative to other cancers in the general population, using data from the registry for Iowa, one of the nine SEER areas. The SEER Program has combined in situ and invasive blad-der cancers when reporting incidence and survival rates begin-ning with the 1985 annual report (2) (cases diagnosed 1973 through 1983). Reasons for making this decision included the following. Incidence rates for invasive bladder cancer had decreased rather dramatically in 1982 and 1983, while the rates for in situ bladder cancer had increased by nearly the same