‘Definitive Work’
Joel M. Topf, MD, a nephrologist with expertise in chronic kidney disease in Detroit, who wasn’t involved in the development of the risk score, called the study “a definitive work on an important concept in oncology and nephrology.”
“While this is not the first attempt to devise a risk score, it is by far the biggest,” he told this news organization. Furthermore, the authors “used a diverse population, recruiting patients with a variety of cancers (previous attempts had often used a homogenous diagnosis, putting into question how generalizable the results were) from six different cancer centers.”
In addition, he said, “The authors did not restrict patients with chronic kidney disease or other significant comorbidities and used the geographic diversity to produce a cohort that has an age, gender, racial, and ethnic distribution, which is more representative of the US than previous, single-center attempts to risk score patients.”
An earlier model used the Kidney Disease: Improving Global Outcomes (KDIGO) consensus definition of AKI of an increase in serum creatinine of 0.3 mg/dL, he noted. “While a sensitive definition of AKI, it captures mild, hemodynamic increases in creatinine of questionable significance,” he said.
By contrast, the new score uses KDIGO stage II and above to define AKI. “This is a better choice, as we do not want to dissuade patients and doctors from choosing chemotherapy due to a fear of insignificant kidney damage,” he said.
All that said, Dr. Topf noted that neither the current score nor the earlier model included serum creatinine. “This is curious to me and may represent the small number of patients with representative elevated creatinine in the derivation cohort (only 1.3% with an estimated glomerular filtration rate [eGFR] < 45).”
“Since the cohort is made up of people who received cis-platinum, the low prevalence of eGFRs < 45 may be due to physicians steering away from cis-platinum in this group,” he suggested. “It would be unfortunate if this risk score gave an unintentional ‘green light’ to these patients, exposing them to predictable harm.”
‘Certainly Useful’
Anushree Shirali, MD, an associate professor in the Section of Nephrology and consulting physician, Yale Onco-Nephrology, Yale School of Medicine, in New Haven, Connecticut, said that having a prediction score for which patients are more likely to develop AKI after a single dose of cisplatin would be helpful for oncologists, as well as nephrologists.
As a nephrologist, Dr. Shirali mostly sees patients who already have AKI, she told this news organization. But there are circumstances in which the tool could still be helpful.
“Let’s say someone has abnormal kidney function at baseline — ie, creatinine is higher than the normal range — and they were on dialysis 5 years ago for something else, and now, they have cancer and may be given cisplatin. They worry about their chances of getting AKI and needing dialysis again,” she said. “That’s just one scenario in which I might be asked to answer that question and the tool would certainly be useful.”
Other scenarios could include someone who has just one kidney because they donated a kidney for transplant years ago, and now, they have a malignancy and wonder what their actual risk is of getting kidney issues on cisplatin.
Oncologists could use the tool to determine whether a patient should be treated with cisplatin, or if they’re at high risk, whether an alternative that’s not nephrotoxic might be used. By contrast, “if somebody’s low risk and an oncologist thinks cisplatin is the best agent they have, then they might want to go ahead and use it,” Dr. Shirali said.
Future research could take into consideration that CP-AKI is dose dependent, she suggested, because a prediction score that included the number of cisplatin doses could be even more helpful to determine risk. And, even though the derivation and validation cohorts for the new tool are representative of the US population, additional research should also include more racial/ethnic diversity, she said.
Dr. Gupta and Dr. Leaf hope their tool “will be utilized immediately by patients and providers to help predict an individual’s risk of cisplatin-associated kidney damage. It is easy to use, available for free online, and incorporates readily available clinical variables.”
If a patient is at high risk, the clinical team can consider preventive measures such as administering more IV fluids before receiving cisplatin or monitoring kidney function more closely afterward, they suggested.
Dr. Gupta reported research support from the National Institutes of Health (NIH) and the National Institute of Diabetes and Digestive and Kidney Diseases. She also reported research funding from BTG International, GE HealthCare, and AstraZeneca outside the submitted work. She is a member of GlaxoSmithKline’s Global Anemia Council, a consultant for Secretome and Proletariat Therapeutics, and founder and president emeritus of the American Society of Onconephrology (unpaid). Dr. Leaf is supported by NIH grants, reported research support from BioPorto, BTG International, and Metro International Biotech, and has served as a consultant. Dr. Topf reported an ownership stake in a few DaVita-run dialysis clinics. He also runs a vascular access center and has participated in advisory boards with Cara Therapeutics, Vifor, Astra Zeneca, Bayer, Renibus Therapeutics, Travere Therapeutics, and GlaxoSmithKline. He is president of NephJC, a nonprofit educational organization with no industry support. Dr. Shirali declared no competing interests.
A version of this article appeared on Medscape.com.