Neoadjuvant Sunitinib Decreases Inferior Vena Caval Thrombus Size and Is Associated With Improved Oncologic Outcomes: A Multicenter Comparative Analysis

Background We analyzed outcomes of neoadjuvant sunitinib in patients with renal-cell carcinoma (RCC) and inferior vena caval (IVC) tumor and compared outcomes to patients who did not undergo neoadjuvant therapy before surgery. Patients and Methods We performed a multicenter retrospective comparison of RCC patients with IVC tumor who underwent neoadjuvant sunitinib before surgery versus those who did not. Response to sunitinib was defined by Response Evaluation Criteria in Solid Tumors (RECIST). Primary outcome was cancer-specific survival. Secondary outcomes included overall survival. Multivariate analysis was performed to identify risk factors associated with primary and secondary outcomes. Kaplan-Meier analysis compared survival in neoadjuvant and primary surgery groups. Results Data of 53 patients were analyzed (19 neoadjuvant sunitinib, 34 primary surgery; median follow-up, 58 months). Eighteen (9 in each group, P = .143) had metastatic RCC. There was no difference in IVC tumor level between the 2 groups (P = .76). After neoadjuvant sunitinib, median primary tumor decreased size from 8.1 to 6.8 cm, and IVC tumor decreased by 1.3 cm. IVC tumor level decreased in 8 (42.1%) of 19 and was stable in 10 (52.6%) of 19; 5 (26.3%) of 19 experienced partial response. Similar proportions of patients underwent robot-assisted or minimally invasive approaches (P = .351), and no differences were noted in complications (P = .194). Multivariate analysis showed neoadjuvant sunitinib was associated with improved cancer-specific survival (odds ratio = 3.28; P = .021). Kaplan-Meier analysis demonstrated significantly longer median cancer-specific survival (72 vs. 38 months, P = .023) for neoadjuvant sunitinib. Conclusion Neoadjuvant sunitinib was associated with a reduction in primary tumor and thrombus size as well as improved survival. Further investigation is needed to determine the utility of neoadjuvant sunitinib in RCC with IVC tumor.