Real-world treatment patterns and survival in patients with synchronous and metachronous metastatic colorectal cancer in the Netherlands

BACKGROUND: Insight into real-world treatment patterns in daily practice of patients with metastatic colorectal cancer (mCRC) is limited. Aim of this population-based study is to provide an overview of treatment and overall survival (OS) of patients with mCRC and to compare differences in treatment between synchronous and metachronous mCRC.

METHOD: All patients with mCRC of whom the primary tumour was diagnosed in the first half of 2015 were selected from the Netherlands Cancer Registry. Data regarding subsequent treatments were collected in 2019. Treatment patterns were compared between patients with synchronous and metachronous mCRC. OS was analysed using the Kaplan-Meier method.

RESULTS: In total, 1532 patients with synchronous mCRC and 870 patients with metachronous mCRC were included. Patients with metachronous mCRC more often underwent local treatment of distant metastases ( P < 0.001). Approximately half of the patients received systemic treatment (ST) after diagnosis of mCRC, with small differences in type of ST between synchronous and metachronous mCRC. Oxaliplatin- and irinotecan-containing regimens were the predominant first- and second-line systemic therapies, respectively. Median OS of all patients with mCRC was 16.0 months [95% confidence interval (CI) 15.0-17.0 months]. Median OS from the start of each subsequent treatment line was 16.3 months (95% CI 15.5-17.5 months) for patients who started first-line ST, 8.9 months (95% CI 8.3-9.7 months) for patients who started second-line ST and 6.1 months (95% CI 5.4-6.7 months) for patients who started third-line ST.

CONCLUSIONS: Real-world data offer valuable insights for mCRC patients in everyday clinical practice, enabling clinicians to provide more informed guidance to their patients.