<p>The development of new anti-cancer drugs has expanded not only the range of renal side effects, but also the number of patients who can receive treatment, including mild renal insufficiency or those receiving dialysis. Because the administration of many drugs must be adjusted to renal function, accurate determination of the glomerular filtration rate can be decisive in determining the drug dosage, but it can also be a parameter to decide whether to include a&#xa0;patient in a study. Since direct measurement is generally not possible or is impractical, renal function is estimated using approximation equations with the aid of markers like creatinine or cystatin&#xa0;C. However, there are limitations in daily clinical practice that should be taken into consideration. Immune-related renal side effects are also associated with some newer substances, such as checkpoint inhibitors, cell therapies, antibodies, and small molecules.</p>