Long term relative survival (RS) in patients with primary metastatic kidney cancer: An analysis of 2,167 patients from the Austrian National Cancer Registry (ANCR).

Abstract

e16069 Background: The introduction of thyrosinkinase inhibitors (TKI) changed the treatment of metastatic kidney cancer fundamentally. In Austria, TKI was in troduced in 2006. To elaborate the potential impact of TKI therapies, we studied trends in OS for patients diagnosed with primary metastatic kidney cancer between1998 and 2015 in Austria. Methods: All patients with primary metastatic kidney cancer aged ≥18 years, diagnosed from 1998-2015 were derived from the ANCR (n = 2,490). Patients diagnosed from 2004-2005 (n = 323) were excluded (transition period of systemic therapies). To evaluate survival differences between patients treated before and after the introduction of Sunitinib (preTKI-era and TKI-era), three periods were defined: 1998-2003 (preTKI-era; N = 937), 2006-2010 (TKI-era P1; N = 687) and 2011-2015 (TKI-era P2; N = 543). Follow-up was complete until December 31st, 2016. RS rates were estimated by using method. The Cox proportional hazard model was used to calculate hazard ratios (HR). Results: A total of 2,167 patients was included in the analysis. The median age of the study population was 70 yrs and did not differ between the three eras. The incidence of T1 tumors increased from 6.9% in the preTKI-era to 10% in the TKI-era while T4 tumors decreased from 15% to 8% (p < .001). Surgery rate declined from 50% in the preTKI-era to 43% in 2011-2015 (p = .02). Five-year RS for patients undergoing surgery slightly increased from 18% in the preTKI-era to 23% in TKI-era P1 (p = .04). For patients without (p = .04). For patients without surgery 5-year OS improved from 5.2% in the preTKI-era to 9.1% in TKI-era P1 (p < .001). Apart from surgery, survival gain was observed for younger patients ( < 75 yrs) of +6% (p = .01), older patients ( > = 75 years) of +0.2% (p = .03) and for T3/T4 tumors of +6% (p = .002). The Relative Excess Risk of dying (RER) for patients treated in the TKI-eras was reduced compared to the preTKI-era (HR 0.78, 95% CI 0.76-0.95) adjusted for sex, age, T-stage and surgery. Survival advantage for patients undergoing surgery remained significant (HR: 0.46, 95% CI 0.41-0.52) after adjustment for TKI-era, sex, age, T-stage. Conclusions: Patients with primary metastatic kidney cancer treated in the TKI era show improved RS compared to the cytokine era. Most benefit was observed in non-surgical patients, younger patients and for T3/T4 disease. Surgery remains as an important therapy for additional survival benefit.