Cancer is a worldwide epidemic that has increased its prevalence exponentially over the last decades. In 2020, 19.3 million new cases of cancer were diagnosed, and there were 10 million deaths from cancer worldwide (1). Cancer patients are susceptible to chemotherapy and immunotherapy treatments that can cause renal complications, such as acute kidney injury (secondary to glomerular disease, acute interstitial nephritis, or acute tubular necrosis), electrolyte disorder, proteinuria, and others (2). Additionally, a higher prevalence of cancer has been demonstrated in patients with chronic kidney disease from various types, those with a kidney transplant, and patients on kidney replacement therapy (Figure 1). Because of a lack of randomized clinical trials that test oncologic treatments in the population with renal diseases, patients with a lower glomerular filtration rate have less opportunity to receive some oncologic treatments. Thus, it is important to optimize their renal function with nephrologist intervention.

The spectrum of renal diseases in cancer patients
Citation: Kidney News 14, 5

The spectrum of renal diseases in cancer patients
Citation: Kidney News 14, 5
The spectrum of renal diseases in cancer patients
Citation: Kidney News 14, 5
For these reasons, multidisciplinary care is important for cancer patients with diminished kidney function. Based on this idea, onconephrology was born. Onconephrology was originally considered a subspecialty that has increased in importance over the last decade, with the purpose to address accurate care of cancer patients and to diagnose and prevent complications. This increase in interest and importance of onconephrology has been evident in multiple ways (3). For example, the number of oral presentations dedicated to onconephrology topics at ASN Kidney Week has increased in the last several years. Likewise, this is also seen in Europe. During the last two European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) congresses (2020 and 2021), there has been an increase in onconephrology topics. In 2020, ERA-EDTA offered a symposium, “New immune therapies and onconephrology.” In addition, a pre-congress course was dedicated to onconephrology (4). During the most recent congress in 2021 (58th ERA-EDTA Congress), there was a symposium dedicated to onconephrology with three lectures and a second symposium, entitled “AKI in special situations,” in which one of the lectures was “AKI in oncology patients” (5).
The recent formation of the American Society of Onconephrology (ASON) in the United States demonstrates the advances of this subspecialty, but this type of international society is lacking in Europe. However, this important increase in the prevalence of onconephrology is observed in the European congress and also reflected in European journals. Two major European journals, Nephrology Dialysis Transplantation (NDT) and Clinical Kidney Journal (CKJ), have published many onconephrology articles (Figure 2). In both onconephrology publications, 15 (37.5%) are reviews, 11 (27.5%) abstracts, 11 (27.5%) original articles, 5 (12.5%) editorials, 1 (2.5%) a letter, and 1 (2.5%) a meeting report.

Distribution of onconephrology articles published in recent years in two European journals
Citation: Kidney News 14, 5

Distribution of onconephrology articles published in recent years in two European journals
Citation: Kidney News 14, 5
Distribution of onconephrology articles published in recent years in two European journals
Citation: Kidney News 14, 5
In Spain, a working group called “Onconephrology” has been created by the Spanish Society of Nephrology. The working group holds regular meetings and multicenter collaborative projects are proposed in different hospitals with onconephrology units, as well as training courses for nephrologists in this subspecialty (6).
Recognition of the importance of onconephrology has increased recently because of the increase in the number of cancer patients with kidney impairment and the need for a multidisciplinary approach in caring for these patients. This need is reflected in the increase of onconephrology in both research and education in Europe, with an aim to optimize the care of cancer patients with kidney impairment and to improve their survival and quality of life.
References
- 1.↑
Sung H, et al. Global cancer statistics 2020: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin 2021; 71:209–249. doi: 10.3322/caac.21660
- 2.↑
Salahudeen AK, Bonventre JV. Onconephrology: The latest frontier in the war against kidney disease. J Am Soc Neprhol 2013; 24:26–30. doi: 10.1681/ASN.2012070690
- 3.↑
Thakkar J, et al. Onconephrology abstracts and publication trends: Time to collaborate. Clin Kidney J 2015; 8:629–631. doi: 10.1093/ckj/sfv085
- 4.↑
ERA-EDTA. 57th ERA-EDTA Congress abstracts. Nephrol Dial Transplant 2020; 35. doi: 10.1093/ndt/gfaa139.SO003; https://academic.oup.com/ndt/search-results?page=1&q=57th%20ERA-EDTA%20Congress%20Abstracts&fl_SiteID=5333&SearchSourceType=1&allJournals=1
- 5.↑
ERA-EDTA. 58th ERA-EDTA Congress abstracts. Nephrol Dial Transplant 2021; 36 (Suppl 1): 5–8. doi: 10.1093/ndt/gfab085.0019; https://academic.oup.com/ndt/search-results?page=1&q=58th%20ERA-EDTA%20Congress%20Abstracts&fl_SiteID=5333&SearchSourceType=1&allJournals=1
- 6.↑
Alonso F, et al. Monographic consultation of onconephrology. Rationale and implementation. Nefrologia (Engl Ed) 2021; 41:154–164. doi: 10.1016/j.nefro.2020.08.008