Antiangiogenic Drug-induced Proteinuria as a Predictive Factor in Metastatic Colorectal Cancer (mCRC)

Background: Treatment with bevacizumab is known to cause adverse effects such as proteinuria, hypertension, fistulas which, in addition to chemotherapy-induced toxicity, affect the quality of life. However, while bevacizumab-induced hypertension has been linked to increased overall survival, data on proteinuria are controversial. Patients and methods: We performed a retrospective analysis to observe the influence of adverse effects on the results of treatment with bevacizumab and chemotherapy in patients with mCRC. Results: : Out of the 3497 mCRC patients admitted to our center between 2014 and 2019, 150 met the criteria for inclusion in our analysis. Of these, 50.7% experienced proteinuria and had reached a longer overall survival (40 versus 25 months, p =0.015) and progression free survival (15 versus 12 months, p =0.039). Patients with anemia during treatment, regardless of grade, had a 20-month shorter survival. The following groups were identified as having a lower risk of death: patients with proteinuria (HR 0.630; 95% CI 0.424-0.935; p =0.022), disease control (HR 0.436; 95% CI 0.291-0.653; p <0.001) and non-metastatic stage at diagnosis (HR 0.477; 95% CI 0.300-0.757; p =0.002). Anemia was a negative prognostic factor (HR 2.153; 95% CI 1.343-3.454; p =0.001). Conclusions: : Proteinuria seems to be a useful predictive factor in mCRC patients undergoing bevacizumab-based systemic therapy. Since it is already routinely assessed in this clinical setting, proteinuria could be easily integrated in the decision-making process and thus allow physicians to further individualize systemic treatments.