Third-line treatment patterns and clinical outcomes for metastatic colorectal cancer: a retrospective real-world study

Background:There are multiple recommendations on the third-line therapy of metastatic colorectal cancer (mCRC); however, no consensus has been reached.Objectives:This study aimed to explore the patient demographics and the real-world third-line treatment landscape of mCRC.Design:A retrospective real-world cohort study.Methods:Electronic medical records of mCRC patients from Tianjin Medical University Cancer Institute and Hospital between 2013 and 2020 were collected. Upon descriptive, comparative, and survival analyses, a retrospective study was conducted to describe demographics and clinical outcomes of mCRC patients receiving third-line treatment.Results:Among 218 mCRC patients receiving third-line therapy, 65.5% received chemotherapy combined with or without targeted drugs, followed by anti-angiogenic monotherapy (18.4%), anti-epidermal growth factor receptor drugs (6.9%) and immunotherapy (6.4%). The overall response rate and disease control rate reached 10.2% and 59.2%, respectively; and median progression-free survival (PFS) and overall survival were 4.0 m and 10.7 m, respectively. After Cox multivariate analysis, we found that therapeutic regime was an independent prognostic factor. Compared to patients receiving anti-angiogenic monotherapy, those receiving chemotherapy combined with or without targeted drugs exhibited better prognosis. For patients whose PFS were longer in the front-line treatment, the PFS of third-line therapy was also relatively longer (p = 0.023). Multiple types of therapies (>3, p = 0.002) or multiple drugs (>5, p = 0.024) in the whole-course management of mCRC are indicators of longer survival.Conclusion:Chemotherapy combined with or without targeted therapy remained dominated third-line choice and showed favorable efficacy compared with anti-angiogenic monotherapy. With the application of more types and quantities of effective drugs, patients would achieve better survival.

Automated summary

This retrospective study investigated the clinical characteristics and real-world treatment patterns of patients with metastatic colorectal cancer (mCRC) at Tianjin Medical University Cancer Institute and Hospital from 2013 to 2020. The majority of patients chose chemotherapy combined with or without targeted therapy as their third-line treatment, while anti-angiogenic monotherapy was less commonly used. Patients receiving chemotherapy combined with or without targeted therapy had better efficacy, and the use of multiple therapies or drugs was associated with longer survival.