Ten tips for kidney biopsy in cancer patients

Renal biopsy is an essential diagnostic tool to be considered in cancer patients, a population in whom renal dysfunction is frequent, multifactorial, and clinically significant. Accurate identification of the underlying lesion is often crucial for guiding oncologic therapy, preventing further renal decline, and improving overall outcomes. However, performing a biopsy in this vulnerable patient group requires careful evaluation of procedural risks and clinical context. This '10 Tips' paper provides a practical framework to support clinicians in selecting appropriate candidates, preparing for the procedure, and interpreting histopathological findings. Special attention is given to high-risk and end-of-life scenarios, where the balance between diagnostic benefit and potential harm becomes particularly delicate. By integrating clinical, procedural, and ethical considerations, this paper aims to promote thoughtful, patient-centred approach to renal biopsy in the complex landscape of onconephrology. Shared decision-making and multidisciplinary collaboration among nephrologists, oncologists, haematologists, and pathologists are essential.