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Strategy for long-term surveillance at the German Childhood Cancer Registry - an update.

BACKGROUND
The objective of this paper is to provide information about the quality (e.g. completeness, response) of long-term surveillance in German paediatric oncology and haematology based on the structures implemented by the German Childhood Cancer Registry (GCCR).


METHODS
The GCCR contacts parents or patients to collect and update information on a minimal set of follow-up health status data (e.g. late relapses, subsequent neoplasms, current address) and exchanges this information regularly with the appropriate clinical trials.


RESULTS
Between 2006 and 2010, GCCR approached a total of about 20,000 patients (contact at the age of 16 years, inquiry concerning the health status) in the context of long-term surveillance. 11,000 addresses of former patients had to be researched via municipal registrar's offices. The response rates ranged from 56% to 68%, the research in municipal offices provided 93-96% valid addresses. Of 46,115 patients diagnosed between 1980 and 2009, 25,283 are in long-term surveillance in 2010.


DISCUSSION
Long-term surveillance requires considerable logistic effort at GCCR and requires that thousands of letters be mailed each year in order to ensure regularly updated information. Long-term surveillance is indispensable for a better understanding of late effects, subsequent neoplasms and quality of life of former childhood cancer patients.