Presentation Authors: Aaron Bradshaw*, San Diego, CA, Umberto Capitanio, Milan, Italy, Robert Uzzo, Philadelphia, PA, Dattatraya Patil, Atlanta, GA, Ahmed Eldefrawy, San Diego, CA, Alessandro Larcher, Milan, Italy, Shreyas Joshi, Philadelphia, PA, Stephen Ryan, Margaret Meagher, Brittney Cotta, Addison Yee, Fang Wan, San Diego, CA, Francesco Montorsi, Milan, Italy, Viraj Master, Atlanta, GA, Ithaar Derweesh, San Diego, CA
Introduction: Criteria for staging of T1 renal tumors into T1a (â‰¤4cm) and T1b (4cm
Methods: Multicenter (UCSD, Emory, Fox Chase Cancer Center, Ospadele San Raffaele) retrospective analysis of patients with cT1 renal cell carcinoma (RCC) undergoing partial or radical nephrectomy. Patients were stratified by tumor size into three groups cT1a (â‰¤2cm, very low risk), cT1b (2cm
Results: 4710 patients were stratified into proposed T1 groups (T1a=856, T1b=2909, T1c=945; median follow-up 39 months). Mean age increased with tumor size (T1a 57.4 yrs, T1b 60.1 yrs, T1c 70.0 yrs, p < 0.001) as did total RENAL scores (T1a 6.5, T1b 7.6, T1c 9.0, p < 0.001). For cT1a, cT1b and cT1c tumors, KMA revealed 5 year RFS of 95.7%, 90.8%, and 80.8%, (p < 0.001; Figure 1a) and 5 year OS of 89.3%, 85.5%, and 73.3% (p= < 0.001, Figure 1b). MVA of RFS revealed increasing age (HR=1.02, p < 0.001), diabetes mellitus (HR=1.41, p=0.017), high tumor grade (HR=2.65, p < 0.001) and increasing tumor stage (Referent T1a; cT1b HR=1.927 p=0.002, cT1c HR=3.687 p < 0.001) as independent risk factors. MVA of OS revealed increasing age (HR=1.05, p < 0.001), diabetes mellitus (HR=1.57, p < 0.001), high tumor grade (HR=1.80, p < 0.001) and increasing tumor stage (Referent T1a; cT1b HR=1.10 p=0.44, cT1c HR=1.747 p < 0.001) as independent risk factors.
Conclusions: Subclassification of cT1 RCC into three clinical stage categories corresponds to distinctive tumor groups whose biological potential varies significantly. Division into three distinct categories may enhance risk stratification, refine preoperative counseling, and augment postoperative follow-up protocols by delineating a very low risk and intermediate risk subset of renal tumors.
Source of Funding: Stephen Weissman Kidney Cancer Research Fund