Bevacizumab related arterial hypertension as a predictive marker in metastatic Colorectal Cancer (mCRC) patients

Purpose: Patients with metastatic colorectal cancer (mCRC) receiving all three active drugs (Irinotecan, Oxaliplatin, Fluorouracil) achieve the best outcome. Bevacizumab added to chemotherapy further improves progression-free (PFS) and overall survival (OS). As arterial hypertension has been reported in all studies involving bevacizumab, we retrospectively analysed the correlation between the modifications of arterial blood pressure and response rate (RR) and PFS in mCRC patients treated with bevacizumab. Patients and methods: Patients with histologically proven mCRC, receiving a first-line chemotherapeutic treatment were eligible. Arterial blood pressure was measured daily, and hypertension graduated according to NCI-CTC V3.0 scale. Results: 74 patients were considered for the present analysis; median age was 57 years (range 31-80). Sixty-seven patients had undergone surgery on primary tumour and, of these, 19 patients had formerly received adjuvant chemotherapy for stage II-III tumours. Chemotherapeutic regimens for metastatic disease were: FOLFIRI (61 patients), FOLFOXIRI (6 patients), XELOX (5 patients), XELIRI (2 patients). Eighteen patients (24.3%) had basal hypertension. Thirteen patients (17.6%) developed G2-G4 arterial hypertension. Six complete (8.1%) and 31 partial (41.9%) responses were recorded. Among patients with induced arterial hypertension, 84.6% achieved a complete or partial response, as compared with 42.6% of patients who did not show this side effect (p=0.006). Kaplan-Meier analysis showed a statistically significant improvement in median PFS for patients with induced-arterial hypertension (15.1 vs 8.3 months, p=0.04). Conclusions: Our data suggest that bevacizumab-related arterial hypertension may represent a predictive factor of response and prolonged PFS in patients with mCRC receiving first-line bevacizumab.