A Study of Angiogenesis Markers in Patients with Renal Cell Carcinoma Undergoing Therapy with Sunitinib.

Background: Sunitinib is a tyrosine kinase inhibitor (TKI) targeting tumour angiogenesis in patients with advanced renal cell carcinoma (RCC). Currently no universally agreed model exists correlating the expression of angiogenesis markers with the success of treatment. Patients and Methods: We retrospectively analysed archival tissue for 59 RCC patients treated with sunitinib. The expression of angiogenesis markers VEGF-A, VEGFR, PDGF beta beta, PDGFR, CCND1 and CA9 was assessed by immunohistochemistry (IHC) and correlated with overall survival (OS) and progression-free survival (PFS). Results: The median OS and median PFS of the whole group of patients was 24.6 months (17.3-34.2) and 19.5 months (11-27) respectively. VEGFA was positive in 29% of tumors, whereas VEGFR was expressed in only 12% of tumours. PDGF beta beta and its receptor were detected in a minority of cases. CCND1 and CA9 were positive in 44% and 60% of cases. Conclusion: The OS and PFS achieved by our patients reflected previous observations seen with sunitinib, but no correlation was found between expression of angiogenesis markers and clinical outcome.