An open-label phase II trial to assess to efficacy of sunitinib as an antieffusion agent in patients with malignant peritoneal and/or pleural effusions

Abstract e14647 Background: Pleural and peritoneal effusions are common in advanced malignant disease and relative resistant to traditional treatments. VEGF-A is considered to be a crucial factor in the biology of accumulation of malignant effusions (ME). Sunitinib is a multi-targeted TKI with a high potency of inhibiting VEGFR2. A treatment that could symptomatically reduce ME would be useful, regardless of its anti-tumoural or anti-angiogenic effect. Refractory patients with symptomatic ME were enrolled to receive 2x6 weeks of daily 37.5mg sunitinib regardless of their primary histology or site. Outcome was measured by time to re-puncture or by measurement of volume ME by CT-scan every 6 weeks or at the end of treatment. Puncture fluids and blood samples were collected for extensive biomarker analysis (VEGFA&C, VEGFR1-3, b-FGF, PDGFA-B, PDGFRα-β, PlGF1-2) on consecutive samples. At present 6 patients have been enrolled. Patients had ovarian cancer (N=3), breast cancer (N=2) and squamous cervical cancer (N=1) as primary tumours. All patients had been extensively pre-treated with 4 to 8 lines of systemic therapy. Three (3/6) patients showed regression of effusion fluid by consecutive CT-scans. Two (2/6) patients had unchanged volume and one (1/6) patient had an increase of fluid volume. Two (2/6) patients stopped the trial early due to toxicity. Two patients (2/6) died during treatment due to disease progression elsewhere. Two patients (2/6) completed the 2 cycles of 6 weeks treatment. Of which, one had sustained reduction in volume fluid accumulation, while the other one had initial stabilisation after one cycle but eventually had increasing volume of ascites. These findings support the hypothesis that sunitinib could be useful in the management of ME. Although the numbers are low, in a majority of patients (5/6) there was reduction or stabilisation of fluid accumulation. Toxicity led to study withdrawal in a third of our patients. An update of patient numbers as well as results of translational/biomarker analysis will be presented at the meeting. No significant financial relationships to disclose.