In:
Journal of Clinical Oncology, American Society of Clinical Oncology (ASCO), Vol. 30, No. 15_suppl ( 2012-05-20), p. 10581-10581
Abstract:
10581 Background: Renal cell cancer (RCC) is characterized by high VEGF production leading to excessive angiogenesis. To visualize VEGF, we performed serial 89 Zr-bevacizumab-PET scans before and during antiangiogenic treatment in RCC patients. Methods: Metastatic (m) RCC patients who received sunitinib (50 mg once daily, 4 out of 6 weeks) or bevacizumab (10 mg/kg every 2 weeks) plus interferon (IFN 3-9 MU 3x/week), underwent 89 Zr-bevacizumab-PET scans at baseline and after 2 and 6 weeks, and CT scans at baseline and every 3 months. Tracer uptake in tumor lesions was quantified with maximum Standardized Uptake Value (SUVmax). Relationship between baseline and Δ SUVmax and time to progression (TTP) was analyzed. Wilcoxon test was used to compare scans, Kaplan-Meier method for survival analysis. Results: 22 out of 26 patients were evaluable, 11 per treatment. On 89 Zr-bevacizumab-PET, 131 out of 231 lesions ≥ 10 mm (detection limit) were visible and 125 quantifiable. Mean SUVmax at baseline was 10.1 (SD 8.4; range 2.3 - 46.9). During bevacizumab/IFN treatment, SUVmax consistently decreased (mean decrease 47.0% 95% CI 39.1-54.9, P 〈 0.0001) at 2 weeks with a further decrease of 9.7% (95% CI 0.86-18.5, P=0.016) at 6 weeks. After 2 weeks sunitinib, there was only a modest decrease in mean SUVmax (14.6%, 95% CI 1.57-27.63, P=0.0064) with a wide range (-80.4% to +269.9%) and an overshoot of 84.4% (95% CI 47.8-120.9, P=0.0001) after 2 drug free weeks. TTP was longer in (n=15) patients with baseline SUVmax 〉 11.1 (highest normal tissue uptake) in the 3 most intense lesions than in those with a lower value (median 89.7 vs 22.8 weeks, HR 0.16, 95% CI 0.04 - 0.70). TTP was longer in patients (n=11) with an absolute Δ SUVmax 〉 6.00 in the most intense lesion at 2 weeks (HR 0.25, 95% CI 0.06-0.98). Conclusions: 89 Zr-bevacizumab-PET visualizes tumor lesions in mRCC patients. Different changes in tumor tracer uptake after start of bevacizumab/IFN versus sunitinib indicate that these drugs induce different angiogenic responses. High baseline SUVmax and large change in SUVmax corresponded with longer TTP, suggesting that 89 Zr-bevacizumab-PET may help to identify patients who benefit the most from antiangiogenic treatment.
Type of Medium:
Online Resource
ISSN:
0732-183X
,
1527-7755
DOI:
10.1200/jco.2012.30.15_suppl.10581
Language:
English
Publisher:
American Society of Clinical Oncology (ASCO)
Publication Date:
2012
detail.hit.zdb_id:
2005181-5
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