The effect of a treatment delay on outcome in metastatic renal cell carcinoma

Objectives: To investigate if a first-line treatment delay (TD) can negatively affect the outcomes of patients affected by metastatic renal cancer. Patients and methods: Patients with a diagnosis of metastatic renal cancer who were ineligible for active surveillance were included in the sample. A TD was defined as the time from the diagnosis of metastatic disease to the start of first-line therapy with tyrosine kinase inhibitors. Results: A total of 835 patients were assessed and 635 were included in the final analysis. The median TD was 6.3 weeks. No significant differences were found in baseline characteristics between patients experiencing a TD below/equal to or above the median value, with the exceptions being the rate of bone metastases (25.3% vs. 35.9%) and advanced disease at diagnosis (34.7% vs. 54.9%). In patients who had received a previous nephrectomy for localized disease, the TD was 5.3 compared to 8.0 weeks for those with metastatic disease at diagnosis (P = 0.001). Among this latter group, 68.7% had received a cytoreductive nephrectomy. In patients with a TD below/equal to and above the median value, the median progression-free survival was 10.3 and 11.2 months, respectively (hazard ratio = 1.03; 95% confidence intervals, 0.86–1.22; P = 0.78); the median overall survival was 27.3 and 28.2 months, respectively (hazard ratio = 1.04; 95% confidence intervals, 0.86–1.27; P = 0.68). The lack of differences was confirmed when adjusted for prognostic factors and baseline characteristics. Conclusions: This study reports that patients with bone metastases and advanced disease at diagnosis have a significant probability of experiencing delayed first-line therapy of more than 6 weeks from the time of diagnosis. However, a TD does not significantly affect outcomes and survival.