Objective: To assess the effect of neoadjuvant targeted molecular therapies (TMTs) on size and level of inferior vena cava tumor thrombi and to evaluate their impact on surgical management.
Methods: We retrospectively analyzed the data of 14 patients treated for a clear cell renal cell carcinoma with inferior vena cava thrombi by neoadjuvant TMT before nephrectomy. Clinical, pathological and perioperative data were gathered retrospectively at each institution. The primitive tumor size and the thrombus size were defined by computed tomography before TMT. The tumor thrombus level was defined according to the Novick's classification.
Results: Before TMT, thrombus level was staged I for 1 (7%), II for 10 (72%) and III (21%) for 3 patients. First-line therapy was sunitinib in 11 cases and sorafenib in 3 cases. Median therapy duration was two cycles (1-5). Three patients experienced major adverse effects (grade III) during TMT. Following TMT, 6 (43%) patients had a measurable decrease, 6 (43%) had no change, and 2 (14%) had an increase in the thrombus. One patient (7%) had a downstage of thrombus level, 12 (85%) had stable thrombi, and 1 (7%) had an upstage. Regarding primary tumor, 7 (50%), 5 (36%) and 2 (14%) patients had a decrease, stabilization and an increase in tumor size, respectively.
Conclusion: Neoadjuvant TMT appears to have limited effects on renal tumor thrombi. This retrospective study failed to demonstrate a significant impact of neoadjuvant TMT on surgical management of clear cell renal cell carcinoma with inferior vena cava tumor thrombi.