Longitudinal GFR trends after neoadjuvant chemotherapy prior to nephroureterectomy for upper tract urothelial carcinoma

Purpose: Renal function dictates sequencing and eligibility for definitive therapy in upper tract urothelial carcinoma. We investigated longitudinal glomerular filtration rate (GFR) changes after neoadjuvant chemotherapy (NAC) and nephroureterectomy (RNU). Materials and Methods: Patients treated with ≥3 cycles of chemotherapy prior to RNU for UTUC from 2000 to 2019 were included. GFR was calculated by CKD-Epi before chemotherapy, before RNU, 1 to 3 months, and 12 months post-RNU. Pathologic stage and overall survival were compared in those with stable GFR (+/-10% of baseline) to the rest of the cohort. Results: One hundred and fifty-two patients received ≥3 cycles of NAC, with 121 (79%) receiving at least 1 cycle of cisplatin. Renal function dropped by mean of 22.3 ml/min/1.73 m² from the beginning of chemotherapy to 1-year post-surgery. In patients receiving cisplatin, a mean decline of 26.2 ml/min/1.73 m² was observed vs. 8.8 ml/min/1.73 m² without cisplatin-based NAC (P < 0.01). GFR after RNU was unchanged between 3 and 12 months postoperatively. At 1 to 3 months after RNU, 19% of patients had GFR<30 ml/min/1.73m². Improvement in GFR during NAC was associated with invasive final pathologic stage (P = 0.018) and worse overall survival (P = 0.049). Conclusions: In patients managed with NAC prior to RNU, renal function stabilizes at 1 to 3 months post-operatively and remains clinically similar for cisplatin or non-cisplatin-based therapy. Improvement in GFR during NAC was associated with higher pathologic stage and poorer survival, especially in those receiving non-cisplatin-based therapy, an observation that requires further investigation.