Abstract P3-15-06: Results of the MARS study on the management of antiangiogenics’ renovascular safety in breast cancer

Abstract

Abstract Background: Anti-VEGF drugs (AVD) are widely used in cancer patients (pts). Hypertension (HTN) and proteinuria (Pu) are class-side-effects of AVD, related to the inhibition of the VEGF pathway. The MARS study has been conducted to assess the renovascular tolerance of these drugs in the clinical setting. Methods: This multicentric, prospective, observational study evaluated the renovascular safety of AVD in pts naive from any AVD, conducted in 7 centres in France, from 2009 to 2012, with a follow-up (f/u) of 1 year. Data collected included: gender, age, serum creatinine (SCr), diabetes, HTN, hematuria (Hu) and dipstick Pu, at baseline and at each visit. Results: 1124 cancer pts were included; 402 breast cancer (BC) pts received bevacizumab (1st line: 14.4%; median durations of treatment: months)). Median age at inclusion was 55 years (19-65). Visceral, bone and cerebral metastasis frequencies were 74.7, 5.1 and 2.5%, respectively. HTN prevalences: 12.4%. Baseline renal assessment retrieved: Pu 23.9%, Hu 16.2%, mean aMDRD 96.4 ml/min/1.73m2 and 14 pts with aMDRD<60. The incidence of de novo Pu and HTN during f/u was 61.7 and 16.8% (Table). 69.7% of pts with Pu at inclusion improved or remained stable. Among pts with de novo Pu, 75.7% afterwards improved/normalized. No grade 4 Pu has been reported. Renal function remained stable with a mean aMDRD of 96.2 at the end of f/u. 7.4% had grade 2-3 SCr increase (no grade 3-4). No thrombotic micro-angiopathy (TMA) was reported. Conclusion: These results on the renovascular safety of bevacizumab in BC pts showed that 1) TMA is rare, 2) Grade 3 Pu developed in 4.6% of pts, with no grade 4, 3) less than 17% developed HTN, and 4) aMDRD was stable. Furthermore, in case of a renovascular effect, investigators followed the recommendations from the French Society of Nephrology (Halimi JM. Nephrol Ther 2008) and no treatment withdrawal for unmanageable renovascular toxicity occurred. Renovascular effects in MARS breast cancer patients treated with bevacizumabRenovascular effectsPrevalence at inclusionIncidence during follow-up (de novo**)Pu* (All grades)23.9%61.7%Pu* (Grade 1)22.2%47.1%Pu* (Grade 2)1.7%10.0%Pu* (Grade 3)0.0%4.6%Pu* (Grade 4)0.0%0.0%Hypertension12.4%16.8%Hu* (All Hu)16.2%42.1%Hu* (Traces/+)11.7%33.2%Hu* (++)2.6%6.3%Hu* (+++)1.9%2.6%SCr increase* (All grades)-80.0%SCr increase* (Grade 1)-68.6%SCr increase* (Grade 2)-7.1%SCr increase* (Grade 3)-0.3%*NCI-CTC v4; **de novo = patients with no event at inclusion and who presented an event during follow-up. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-15-06.