Pathological evidence of necrosis in recurrent renal mass following treatment with sunitinib.

Sunitinib is a highly potent, selective vascular endothelial growth factor-receptor types 1 to 3, platelet-derived growth factor (PDGF)-R-alpha, and PDGF-R-ss. Preclinical data suggest that sunitinib (SU11248) has antitumor activity that may result from both inhibition of angiogenesis and direct antiproliferative effects on certain tumor cell types. Sunitinib resulted in tumor shrinkage in 80% of patients who had failed treatment with Bevacizumab and 13% of patients demonstrated an objective Response Evaluation Criteria in solid Tumors (RECIST) in a study presented at the 2006 American Society of Clinical Oncology (ASCO) meeting. We report the first published pathological evidence of sunitinib's effect on recurrent renal cell carcinoma. This was seen in a patient with renal cell carcinoma who developed a renal fossa recurrence 2 years following radical nephrectomy. Tumor shrinkage was evident in the nephrectomy bed after treatment with sunitinib. The pathology of the resected retroperitoneal mass and its implications are discussed.