Onconephrology is a new and evolving subspecialty that focuses on all aspects of kidney disease in cancer patients. Given that up to a quarter of patients with a cancer diagnosis will develop some form of kidney impairment, a discipline that aims to understand and manage the overlapping fields of nephrology and oncology is needed. Topics considered to be part of onconephrology are electrolyte disorders of malignancy, secondary glomerular diseases of cancer, chemotherapy and targeted therapy-related kidney complications, paraproteinemias, thrombotic microangiopathies, hematopoietic stem cell transplant (HSCT)-related kidney diseases, tumor lysis syndrome, and acute kidney injury (AKI) in the cancer patient. Other topics include the ethics of providing dialysis in a dying cancer patient, postnephrectomy kidney disease and obstructive nephropathy, dosing of chemotherapy in chronic kidney disease (CKD) patients, and renal cell cancer. This chapter serves as an overview of key onconephrology topics.
ACUTE KIDNEY INJURY IN THE CANCER PATIENT
The overall incidence of cancer is rising in the United States. The overall incidence of both acute and CKD in cancer patients is unknown. AKI is thought to be fairly common in cancer patients. Based on a Danish population study, the 1-year risk of AKI in patients with cancer, defined as a greater than 50% rise in serum creatinine, is 17.5% with a 27% risk over 5 years. Unfortunately, many cancer patients are left with CKD following AKI episodes.
Four salient features that can be deduced from major studies are (1) the incidence of AKI among hospitalized cancer patients (12%) is higher than that of patients without cancer; (2) acutely ill cancer patients admitted to the ICU have a higher risk of AKI; (3) some cancers are associated with higher risk of AKI than others (kidney, gall bladder, liver, myeloma, and pancreas); and (4) treatment with HSCT, especially myeloablative allogenic HSCT, further raises the risk of AKI associated with malignancies.
AKI in patients with cancer may occur by at least two mechanisms; as a complication of a particular cancer treatment (eg, tumor lysis syndrome, drug-induced nephropathy, post-transplant-related kidney diseases, and surgical procedures) or related to the neoplasm itself (eg, renal cell cancer, anatomic obstruction due to a metastatic lesion or obstructing mass, and myeloma/amyloid affecting the kidney). The cancer patient developing AKI has a worse prognosis than one without kidney impairment. Table 17–1 summarizes the prerenal, intrinsic, and postrenal causes of AKI in the cancer patient.
Table 17–1.Prerenal, intrinsic, and postrenal causes of AKI in the cancer patient. |Favorite Table|Download (.pdf) Table 17–1. Prerenal, intrinsic, and postrenal causes of AKI in the cancer patient.
|Prerenal ||Intrinsic ||Postrenal |
Renal hypoperfusion due to sepsis, ascites, and effusions
Volume depletion (↓ oral intake, diarrhea, overdiuresis)
Impaired cardiac output
Hepatic sinusoid obstructive syndrome
Nonchemo drugs (NSAIDS, ACEI/ARB, calcineurin inhibitors)
Capillary leak syndrome (eg, due to IL2)
Chimeric antigen receptor (CAR) T-cell therapy...