Presentation Authors: ning shao*, yuan qu, fang wan, ding ye, shanghai, China, People's Republic of
Introduction: In light of the disease-free survival (DFS) benefit with sunitinib, NCCN guideline recommended adjuvant sunitinib and surveillance as options for high-risk clear cell renal cell carcinoma (ccRCC) patients after surgery. However, DFS could not reflect individual prognosis accurately after initial disease management. Conditional DFS (CDFS) could provide more relevant prognostic information at each follow-up time. Although previous studies reported survival estimates at diagnosis, data on CDFS for these patients are still lacking.
Methods: To evaluate CDFS in patients with high-risk ccRCC treated with or without adjuvant sunitinib based on two large RCTs (S-TRAC and ASSURE).The primary end point was CDFS and the second end point was smooth hazard ratios (HR) for the prediction of relapses. The differences of conditional survival were compared with the calculation of d value. P-value was used to assess the differences of smooth HRs between groups.
Results: A total of 1329 patients (sunitinib group n = 667; placebo group n = 662) with median follow-up 6.54 years were enrolled for CDFS analysis. CDFS improved continuously with disease-free survivorship increasing in both sunitinib and placebo group with minimal difference between two groups. In placebo arm, the CDFS of surviving to five year after living 1, 2, 3, and 4 years were 65%, 78%, 87%, and 95% (observed 5-year DFS: 51%). In very high-risk subset according to UISS classification, the CDFS of surviving to five year after living 1, 2, 3, and 4 years were 62%, 72%, 87% and 93% (observed 5-year DFS: 47%). The increase of CDFS was more prominent in very high-risk subset after living disease free for 3 years. Dynamic changes of HR showed adjuvant sunitinib significantly decrease risks during the first 1.5 years after surgery (P < 0.03).
Conclusions: Our study provided contemporary data of CDFS and change of relapse HR in high-risk ccRCC patients after adjuvant sunitinib or placebo. The remarkable improvement in CDFS during follow-up highlighted the importance of disease-free interval as a strong indicator in patient counseling and surveillance planning.