Treatment of patients with screen-detected colorectal cancer is less strenuous: a nationwide cohort study with long-term follow-up.

Objective: During the last two decades, organised colorectal cancer (CRC) screening has been widely implemented. It remains to be established if screen-detected CRC (SD-CRC) is associated with reduced long-term requirements for treatment as compared with patients with non-screen-detected CRC (NSD-CRC).

Study Design And Methods: This nationwide cohort study evaluated differences in treatment and healthcare contacts from the date of diagnosis to two years after comparing patients with SD-CRC and NSD-CRC. Data were collected from national healthcare registers, including patients aged 50-75 years and diagnosed with CRC between January 1st 2014 and March 31st 2018. Analyses were stratified into UICC stages and adjusted for sex, 5-year age groups, type of cancer (colonic/rectal), and Charlson comorbidity index score to address healthy user bias.

Results: In total, 12,040 patients were included, 4708 with SD-CRC and 7332 with NSD-CRC. In patients with SD-CRC, the duration of hospitalisation and rate of emergency surgery were reduced by 38 % (relative risk [RR] = 0.62) and 66 % (RR = 0.34), respectively. Moreover, this group was characterised by a 75 % reduction in oncological outpatient visits (RR = 0.35) and a reduced number of treatments with chemotherapy (RR = 0.57) and radiotherapy (RR = 0.50). There were no significant differences between the two populations in the rates of metastasectomy and the number of contacts with primary healthcare providers.

Conclusion: Compared to patients with NSD-CRC, patients with SD-CRC experience less hospitalisation and treatment within the first two years after diagnosis.