Login to Access Video or Poster Abstract: MP16-12
Sources of Funding: Sirtex Medical Limited

Introduction

Endpoints for RCC continue to evolve with increased emphasis on patient-reported outcomes alongside efficacy and safety. SIRT is a procedure used for unresectable liver tumors that may bring benefits in primary RCC patients (pts) unsuitable for nephrectomy. RESIRT is the first study to evaluate SIRT for primary RCC aiming to assess safety as a primary objective. Secondary objectives included quality of life (QoL).

Methods

RCC pts not amenable for or who declined conventional therapy were eligible. A single transfemoral microcatheter administration of Y-90 resin microspheres (Sirtex, Australia) was delivered super-selectively via the renal artery to the tumor at intended radiation doses of 75, 100, 150, 200, 300 Gray and a procedural endpoint of imminent stasis in a dose-escalation design. Pts were assessed for 12 months (mo) after SIRT. The primary endpoint was safety/toxicity 30 days post-SIRT. Secondary endpoints included safety/toxicity at other time points, renal function and QoL assessed by the RCC QoL Symptom Index with scores ranging from 0 (worst) to 100 (best)._x000D_

Results

21 pts were recruited: mean age 75.0 years (± 9.3); 8 (38%) had metastases and 12 (57%) had chronic kidney disease stage 3; 7 (33%) had prior total contralateral nephrectomy, 1 (5%) received pazopanib and 1 (5%) progressed after cryotherapy to the target organ. Median follow-up was 12.0 mo (95% CI 11.9-12.1); 14 pts completed 12 mo follow-up, 5 died before study completion (all mRCC at study entry), 1 withdrew and 1 is still in follow-up. The intended Y-90 doses were delivered without any dose-limiting toxicity. 18 (86%) pts reported adverse events (AEs) of any causality within 30 days of SIRT and 4 (19%) reported serious AEs (SAEs), none of which was SIRT related. Over 12 mo, 10 (47.6%) pts reported grade ≥3 AEs and 10 (47.6%) pts experienced SAEs but none of these was SIRT related. Mean creatinine clearance was 76.1 mL/min at baseline and 68.9 mL/min at 12 mo. Mean serum creatinine levels and blood urea levels were stable during the study period. The mean (±SD) QoL score was 74.6 (±15.8) at baseline and 74.8 (±13.4) at 12 mo. The mean change from baseline was 1.7 (±12.5) at day 30 (p=0.565) and -4.1 (±14.7) at 12 mo (p=0.319).

Conclusions

This pilot study demonstrated good tolerability of SIRT using Y-90 resin microspheres for RCC at all dose levels including imminent stasis with no major impact on renal function or QoL over 12 months.

Funding

Sirtex Medical Limited