Baseline kidney function predicts renal decline in urothelial cancer chemotherapy study

Baseline kidney function was the only factor independently associated with renal-function decline during platinum-based chemotherapy in a retrospective study of 86 patients with advanced urothelial carcinoma. The cohort included 66 patients receiving gemcitabine plus cisplatin and 20 receiving gemcitabine plus carboplatin. In multivariable analysis, chemotherapy regimen, hemoglobin and corrected calcium were no longer independently associated with the change in estimated glomerular filtration rate, or eGFR, while baseline eGFR remained significant.

Researchers at a single center analyzed patients who received first-line gemcitabine plus either cisplatin or carboplatin between 2014 and 2024. The primary endpoint was the change in renal function during treatment, defined as baseline eGFR minus the lowest eGFR recorded during chemotherapy; a larger value therefore represented a greater absolute decline. Because renal measurements had skewed distributions, the investigators used non-parametric tests for comparisons between groups. Variables associated with the outcome in univariable analyses at p < 0.10 were entered into a multivariable linear regression.

The two treatment groups differed at baseline. Patients receiving gemcitabine plus carboplatin were older and had significantly lower baseline eGFR than those receiving gemcitabine plus cisplatin. They also had a smaller distribution of absolute eGFR decline in the univariable comparison. The univariable regression coefficient for regimen, expressed as gemcitabine plus cisplatin versus gemcitabine plus carboplatin, was −16.116, with a 95% confidence interval of −23.317 to −8.915 and p < 0.001. However, regimen was not independently associated with renal decline after baseline eGFR and the other eligible variables were included in the multivariable model.

Baseline eGFR had a strong positive correlation with the amount of renal-function decline across the cohort, with r = 0.794 and p < 0.001. The multivariable coefficient for baseline eGFR was 0.523, with a 95% confidence interval of 0.396 to 0.650 and p < 0.001, indicating that each unit of baseline eGFR was associated with an estimated 0.523-unit increase in the absolute decline. The investigators attributed the smaller unadjusted decline observed in the carboplatin group to treatment selection based on pre-existing renal impairment rather than to demonstrated differences in regimen-specific nephrotoxicity. The study did not establish that carboplatin was less nephrotoxic than cisplatin. Its retrospective design, single-center setting, unequal group sizes and small carboplatin subgroup also limit generalization. The results identify baseline renal function as the principal measured predictor of eGFR decline in this population, rather than providing evidence that either chemotherapy regimen prevents kidney injury or establishing which regimen an individual patient should receive.

Subject of Research: Baseline eGFR as a predictor of renal decline during platinum-based chemotherapy for advanced urothelial carcinoma

Article Title: Predictors of renal function decline during platinum-based chemotherapy in advanced urothelial carcinoma

Article References: Fukushima, K., Miyasaka, M., Shikano, R., Higuchi, S., Asada, S., & Hashimoto, T. (2026). Predictors of renal function decline during platinum-based chemotherapy in advanced urothelial carcinoma. BMC Cancer. https://doi.org/10.1186/s12885-026-16897-0

Image Credits: AI Generated

DOI: 10.1186/s12885-026-16897-0

Keywords: urothelial carcinoma, renal function, estimated GFR, cisplatin, carboplatin, platinum chemotherapy, nephrotoxicity, retrospective study, Predictors, renal, function, decline