Pretreatment staging of colon cancer in the Swedish population

Abstract

Preoperative staging of colon cancer according to Swedish national guidelines implies imaging evaluation of the primary tumour, liver and lungs. Failure to adhere to these guidelines results in negative scorings in the national registration system. In the present study we report the extent of compliance with these guidelines. Since 2007 clinical data on all patients diagnosed with colon cancer in Sweden have been collected in a national database. This includes information on pretherapeutic diagnostic imaging performed, pretherapeutic TNM stage and data on treatment and follow-up. All patients diagnosed with colon cancer in Sweden between 2007 and 2010 were included. Nine thousand and eight-three patients (i.e. 60.5% of all patients) had a complete pretherapeutic radiological evaluation; 65.2% had a CT or MRI of the primary tumour, whereas over 80% had examinations of the liver and lungs. There were no difference related to sex, but more patients under 75 years had a complete evaluation. There were large differences between different regions; one region performed a complete evaluation of 78.3% of all patients. The proportion of patients examined increased from 53.9 to 65.0% during the study period. Elective cases were more frequently evaluated before treatment than those with an emergency presentation. Most patients in Sweden had a complete pretreatment imaging evaluation of the colon cancer with geographical and time-dependent variations. Knowledge of the importance of these variations and correlation of pre- and postoperative TNM stage is warranted, and such studies are ongoing.