Does visceral fat area (VFA) have predictive value for hypertension (HTN) and progression-free survival (PFS) in patients (pts) with stage IV NSCLC receiving bevacizumab (Beva)?

Abstract

e18005 Background: Visceral fat releases pro-angiogenic factors that may promote tumour growth. VFA has been suggested as a predictor of outcome in colorectal and renal cancer pts receiving anti-VEGF agents (Guiu, Gut 2010; Ladoire, Oncologist 2011). Moreover, HTN seems to reflect the intensity of VEGF pathway inhibition, and could also predict outcomes in pts receiving Beva. We postulated that VFA could impact both the activity and toxicity of Beva. Methods: An electronical medical record review identified all pts with stage IV non-squamous NSCLC who received a platinum doublet plus Beva as first-line treatment in our outpatient unit. Beva was continued until disease progression or unacceptable toxicity in pts with response or stable disease after 6 cycles. VFA was determined from pre-treatment CT scans. HTN was monitored at home twice daily according to international guidelines, and graded according to the NCI-CTC v4.0 criteria. Pts were dichotomized according to their VFA (above or below the median), and potential associations linking VFA to HTN, PFS and OS were examined. Results: A total of 77 pts (65% males, 64% smokers, 36% with a PS of 2, median age: 57 years, range 38-86) were eligible for this analysis. Eighteen pts (23%) had a past history of HTN, well controlled at initiation of Beva. A total of 730 cycles of bevacizumab (median/pt: 6, range 2-22) were given. Grade ≥ 2 HTN was observed in 26 (34%) pts. At a median follow-up of 10.1 months (range: 1.0-35.3), the median PFS and OS were 6.9 months (95%CI: 5.6-8.6) and 10.6 months (95%CI: 9.8-11.7), respectively. Median VFA was 113.2 cm2 (range: 27.2-265.2). HTN was significantly more frequent in pts with a low VFA (46% vs. 21 %, OR 3.1, p = 0.03). Patients with a low VFA had a significantly longer PFS: 8.5 (95%CI: 6.4-9.4) vs. 5.6 months (95%CI: 4.8-7.5), p = 0.04. No difference was observed regarding OS. Conclusions: In this series of unselected NSCLC pts receiving bevacizumab-based chemotherapy, pts with a low VFA were more likely to experience HTN and a better PFS than pts with a high VFA. Further studies are required to validate this biomarker in different datasets.