[Completeness of the cancer registry].

In 1985 the regional cancer registry in the IKMN area started. Pathology reports are used as the primary source of information for the registry. In order to evaluate the completeness of the registry, the registry database was compared with the discharge diagnosis register of the participating hospitals (LMR). In 1986 a total of 3546 tumours were registered by the registry, using the pathology reports as the primary source. The comparison with the LMR revealed that 616 patients were included in the cancer registry but not in the LMR. On the other hand 376 patients, in 180 of whom the diagnosis was confirmed by pathological examination while in 196 the diagnosis was based on clinical grounds only, were missing in the registry. Specifically, tumours of the central nervous system, liver, gallbladder, bile ducts and pancreas were missed in a high percentage. It is concluded that--even with an optimal pathology notification system--the LMR check is necessary to avoid underregistration. Omitting this check results in a 5% underregistration.