Later lines of systemic therapy in patients with metastatic colorectal cancer: real-world data from a setting with barriers to access cancer therapies.

Background: Regorafenib and trifluridine/tipiracil (TFD/TPI) are oral systemic therapies with survival benefit in chemorefractory metastatic colorectal cancer (mCRC) patients, but they are not widely available worldwide. We aimed to evaluate the treatment patterns and outcomes of patients with limited access to these drugs. Methods: Retrospective study involving 510 patients with mCRC who were treated at five different centers in Brazil, from January 2011 to December 2019. We analyzed the characteristics and clinical outcomes of patients who were exposed to third-line and beyond systemic therapy (N=148). Results: A total of 148 (29%) and 73 (14%) patients received third- and fourth-line therapies, respectively. Most patients had left-sided tumors (80%) and had undergone primary tumor resection (87%) and metastasectomy (62%). From the initiation of third-line therapy, median follow-up was 17.8 months and median overall survival (OS) was 13.1 months (95% confidence interval: 8.1-18.0) (58% of deaths). The most adopted therapies were reexposure to previous chemotherapy regimens (85% third-line and 71% fourth-line), followed by regorafenib (13% and 25%) and TFD/TPI (2% and 4%). In multivariable analysis, male patients and right-sided tumors were significant unfavorable prognostic factors for OS. Conclusions: In a real-world setting with barriers to accessing the standard of care of chemorefractory mCRC, reexposure to chemotherapy was the main therapeutic strategy, with potential negative influence on OS. Our study highlights how barriers hamper the achievement of health equity in cancer care and increases the awareness of patients and stakeholders, contributing to engaging them in ensuring equitable access to high-quality cancer care.