Phase II dose escalation study of sorafenib in patients with metastatic renal cell carcinoma (mRCC) who have had prior treatment with VEGFR-TKI antiangiogenic treatment. - Mancuso,A.P.; Donato De Paola,E.; Catalano,A.; Calabrò,F.; Messina,C.; Zivi,A.; Cerbone,L.; Vigna,L.; Caristo,R.; Sternberg,C.N. (J Clin Oncol, 2009)