Influence of baseline renal function and dose reduction of nephrotoxic chemotherapeutic agents on the outcome of metastatic urothelial carcinoma: A retrospective study

Objectives:  To investigate the influence of baseline renal function and dose reduction of chemotherapeutic agents on the outcome of metastatic urothelial carcinoma patients with renal impairment. Methods:  A total of 57 patients with metastatic urothelial carcinoma treated by systemic chemotherapy were included in the present study. The 24 h-creatinine clearance was measured before each cycle and dose reduction was carried out according to our guidelines. Patients were divided into two groups according to baseline 24 h-creatinine clearance: fit group (60 mL/min/1.48 m2≤) and unfit group (60 mL/min/1.48 m2>). Clinical characteristics and final outcomes were compared between the two groups. Results:  There was no significant difference in the total number of chemotherapy cycles of each patient between the two groups (fit group: median 5; unfit group: median 4; P = 0.7466), although dose reduction was carried out significantly more often in the unfit group than in the fit group during treatment (fit group: median 0 cycles; unfit group: median 3.5 cycles; P = 0.0016). Overall, the median survival was 16 months. There was a significant survival difference between the two groups (fit group: median 17 months; unfit group: median 10 months; P = 0.0419). On multivariate analyses, impaired renal function at the baseline remained an adverse factor (HR 2.27, P = 0.01). Conclusions:  “Unfit” was a poor prognostic factor for metastatic urothelial carcinoma. The dose reduction strategy contributed to continuous treatment in the unfit group. However, its contribution to the prognosis of unfit patients is uncertain.