Response of the Primary Tumor to Neoadjuvant Sunitinib in Patients With Advanced Renal Cell Carcinoma

Abstract

We assessed the activity of neoadjuvant sunitinib on primary renal tumors in patients with advanced renal cell carcinoma as well as the feasibility and safety of subsequent surgical resection. A total of 19 patients with advanced renal cell carcinoma deemed unsuitable for initial nephrectomy due to locally advanced disease or extensive metastatic burden were treated with 50 mg sunitinib daily for 4 weeks on followed by 2 weeks off. Tumor response was assessed by Response Evaluation Criteria in Solid Tumors every 2 cycles and the rate of conversion to resectable status was estimated. Median patient age was 64 years and initial median radiographic renal tumor size was 10.5 cm. Clinical stage was N+ (10) and M+ (15). No patients experienced a complete response. Partial responses of the primary tumor were noted in 3 patients (16%), 7 (37%) had stable disease and 9 (47%) had disease progression in the primary tumor. Overall tumor response included 2 patients (11%) with partial response, 7 (37%) with stable disease and 10 (53%) with disease progression. At a median followup of 6 months (range 1 to 15) 4 patients (21%) had undergone nephrectomy and 5 died of disease progression. No unexpected surgical morbidity was encountered. Viable tumor was present in all 4 specimens. Sunitinib was associated with grade 3–4 toxicity in 7 patients (37%) and treatment was discontinued in 1 due to toxicity. Administration of sunitinib in patients with advanced renal cell carcinoma with the primary tumor in place is feasible and can lead to a reduction in tumor burden that can facilitate subsequent surgical resection.