Utilization of radiation therapy in Norway after the implementation of the national cancer plan--a national, population-based study

Purpose To estimate actual utilization rates of radiation therapy (RT) in Norway, describe time trends (1997-2010), and compare these estimates with corresponding optimal RT rates. Methods and Materials Data from the population-based Cancer Registry of Norway was used to identify all patients diagnosed with cancer and/or treated by RT for cancer in 1997-2010. Radiation therapy utilization rates (RURs) were calculated as ( 1 ) the proportion of incident cancer cases who received RT at least once within 1 year of diagnosis (RUR 1Y ); and ( 2 ) the proportion who received RT within 5 years of diagnosis (RUR 5Y ). The number of RT treatment courses per incident cancer case (TCI) was also calculated for all cancer sites combined. The actual RURs were compared with corresponding Australian and Canadian epidemiologic- and evidence-based model estimates and criterion-based benchmark estimates of optimal RURs. The TCIs were compared with TCI estimates from the 1997 Norwegian/National Cancer Plan (NCP). Joinpoint regression was used to identify changes in trends and to estimate annual percentage change (APC) in actual RUR 1Y and actual TCI. Results The actual RUR 5Y (all sites) increased significantly to 29% in 2005 but still differed markedly from the Australian epidemiologic- and evidence-based model estimate of 48%. With the exception of RUR 5Y for breast cancer and RUR 1Y for lung cancers, all actual RURs were markedly lower than optimal RUR estimates. The actual TCI increased significantly during the study period, reaching 42.5% in 2010, but was still lower than the 54% recommended in the NCP. The trend for RUR 1Y (all sites) and TCI changed significantly, with the annual percentage change being largest during the first part of the study period. Conclusions Utilization rates of RT in Norway increased after the NCP was implemented and RT capacity was increased, but they still seem to be lower than optimal levels.