MP57-06 LIMITED BENEFIT OF TARGETED THERAPIES ON IVC THROMBUS IN RENAL CELL CARCINOMA

Abstract

INTRODUCTION AND OBJECTIVES: The standard treatment for patients with renal cell carcinoma extending into the inferior vena cava is radical nephrectomy and tumor thrombectomy. However, not all patients are eligible for surgery, and in some cases targeted therapies are needed because of their potential to downsize the tumor. But the clinical benefit of targeted therapies on vena caval tumor thrombus of RCC remains unclear. Objective: To evaluate the cytoreductive effects of targeted therapies on renal cell carcinoma with inferior vena caval tumor thrombus (IVC thrombus). METHODS: 19 patients with IVC thrombus who were treated with targeted molecular therapies (TMT) at our hospital were retrospectively analyzed. Sunitinib was administered in 17 patients, sorafenib in 1, and temsirolimus in 1. Thrombus size and level before and after TMT were measured by enhanced CT or MRI. Patients and tumor characteristics were compared between the patients who showed decrease of IVC thrombus height with TMT and those who did not show any decrease. RESULTS: 14 (74%) of the patients were male, and the mean age of the group was 66 years. The left side of the kidney had primary tumors in 11 patients and the right side in 8. Before the therapy thrombus level waszTin 2 patients (11%), zU in 9 (47%), zV in 4 (21%), and zW in 4 (21%). The median duration of therapy was 2 cycles. Following therapy, the tumor thrombus increased in height in 4 patients (21%), remained the same in 1 casei5%j, and decreased in 14 (74%). However, the mean reduction of the thrombus height was only 14mm. The thrombus level decreased only in 3 patients (16%), all of whom were treated with sunitinib. After TMT, 10 patients (43%) received thrombectomy. Comparison of all the data collected between the two groups failed to demonstrate any statistically significant factors, although a high neutrophil count and clinical node metastases were marginally statistic. CONCLUSIONS: Our study showed the clinical benefit of targeted therapies on IVC thrombus of the renal cell carcinoma was limited. Thus targeted therapy in the neoadjuvant setting can be considered in selected patients.