Prognostic Impact of the Components of Progressive Disease on Survival After First-Line Tyrosine Kinase Inhibitor Therapy for Metastatic Renal Cell Carcinoma.

BACKGROUND: According to the Response Evaluation Criteria in Solid Tumors (RECIST) classification, progressive disease (PD) is defined as target lesion growth (TLG), unequivocal non-target lesion growth (NTLG), or new lesion appearance (NLA). The prognostic impact of the components of PD in tyrosine kinase inhibitor (TKI) therapy for metastatic renal cell carcinoma (mRCC) remains unknown.

OBJECTIVE: We retrospectively evaluated the prognostic impact of these PD components on survival in patients with mRCC after first-line TKI therapy.

PATIENTS AND METHODS: Patients were divided into three groups (TLG, NTLG, and NLA) based on the components of PD. Progression-free survival (PFS) and overall survival (OS) after first-line TKI therapy were compared between groups using the Kaplan-Meier method and log-rank test. The predictive impact of the PD components was evaluated using multivariate analyses.

RESULTS: Among the 116 patients included, 80 (69.0%) had TLG, 18 (15.5%) NTLG, and 69 (58.6%) NLA. The mean PFS and OS were shorter for patients with TLG than those without TLG (PFS, 7.1 vs. 11.6 months, p = 0.0071; OS, 18.2 vs. 25.5 months, p = 0.0091). TLG was an independent predictor of PFS (hazard ratio [HR], 1.59; 95% confidence interval [CI], 1.02-2.51; p = 0.0395) and OS (HR, 1.67; 95% CI, 1.02-2.83; p = 0.040). NTLG and NLA were not associated with survival.

CONCLUSIONS: In this retrospective single-center study, patients with TLG had poor survival after first-line TKI therapy for mRCC. Thus, individual components of PD influence patient prognosis.