Predictors of Contrast-Induced Nephropathy in Patients with Cancer: A Retrospective Cohort Study at a Tertiary Cancer Center

Background: Contrast induced nephropathy is a major cause of renal injury, especially in patients at risk. Cancer patients often undergo repeated imaging as part of diagnosis and follow up. Furthermore, cancer-related factors such as nephrotoxic chemotherapy, tumor lysis syndrome, paraneoplastic syndromes, and frequent comorbidities add the risk of nephrotoxicity. Nevertheless, contrast nephropathy remains under-recognized in oncology clinical setting and professional guidelines. In this analysis we aim to identify factors contributing to contrast induced nephropathy in cancer patients treated at a tertiary cancer center. Methods: During the month of April 2024, all patients undergoing contrasted CT imaging were randomly identified. Contrast nephropathy was gauged as either 25% increase in baseline serum creatinine or 0.5 mg/dL elevation in absolute serum creatinine value within 2-5 days of contrast intravenous administration. Patients and disease characteristics were captured along with creatinine levels. Logistic regression analysis was used to identify risk factors with statistical significant p value <0.05. Results: 150 patients received intravenous contrast, the median age was 64 years (range 20-90). The median baseline serum creatinine was 0.7 mg/dL (range 0.3-1.3). 45 (30%) developed acute kidney injury, the median serum creatinine 72 hours post-contrast 0.92 mg/dL (range 0.3-8.3). There was no statistical significant correlation between contrast nephropathy and the following variables: age, comorbidities (heart failure, diabetes), medications (metformin), single kidney, myeloma disease, dose of contrast and use of IV fluids. While hypertension (p=0.016), use of NSAIDs or ACE inhibitors (p<0.001) and baseline serum creatinine ≥0.8 mg/dL (p=0.035) were significantly associated with contrast nephropathy. Conclusion: Cancer patients at high risk of contrast induced nephropathy, we identified hypertension, NSAIDs, ACE inhibitors and baseline serum creatinine ≥0.8 mg/dL as predictors for contract induced kidney injury. Nevertheless, further studies are required to validate our results and identify other predictors.