Modifications of renal function in cancer patients undergoing repeated and frequent administrations of iodinated contrast mediuma (CM): a multicentric retrospective study from Italy

Background: Contrast-enhanced computed tomography (CECT) is the imaging of choice for the diagnosis, staging, and follow-up of cancer patients, not to take into account its role to evaluate response to oncological treatments; in fact, it has been estimated that 47% of all CECTs are prescribed by Oncologists. Comorbidities, nephrotoxic concomitant medications, as well as chronic dehydration from different causes (nausea and vomiting, diarrhea, etc …) expose cancer patients to a higher risk of developing acute kidney injury (AKI) from CM. Risk factors, definition (PC-AKI vs CI-AKI) and preventive measures have been recently reconsidered, ultimately downsizing the incidence of this adverse event. Methods: Aim of this study was to retrospectively assess the effects on renal function of repeated CM administrations in 407 oncological patients on active treatment, collected from 5 Italian oncology departments; patients should have undergone at least 3 CECT (on the average 3.5) within a single year (Fig I). Results: According to our study, neither significant differences in eGFR values (calculated with the CKD-EPI formula) between the baseline and the different post-CECT timepoints, nor AKI cases (defined according to the RIFLE criteria), were recorded. Conclusions: Repeated CM administrations in cancer patients did not lead to a worsening of renal function, confirming that CI-AKI has a significantly lower incidence than previously thought. Notably, 80% of the patients examined were found to be at low- risk, highlighting some kind of reluctance of Medical Oncologists and Radiologists to perform CECTs in these patients. On the contrary, the administration of CM could, and should, be freely used, in cancer patients, even in those at a higher risk.