Kidney Outcomes and Hypertension in Survivors of Wilms Tumor: A Prospective Cohort Study.

Supported by a Pilot Grant from the Children's Hospital of Philadelphia Center for Pediatric Clinical Effectiveness (to D.C.). D.C. is also supported by the NIH/NIDDK (K23 DK125670). G.T. was supported by the NIH/NIDDK (K23 DK106428). Ja.G. was supported by NIH/NIDDK (K08 DK110536). M.D. was supported by the NIH/NIDDK (K23 DK093556). The NIH and NIDDK had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript. The views expressed in this article are those of the authors and do not necessarily represent the official view of the NIDDK nor NIH. G.T. serves on the scientific advisory boards for Allena Pharmaceuticals, Novome Biotechnology, and Dicerna Pharmaceuticals and serves as a consultant for Alnylam Pharmaceuticals, all of which are unrelated to this work. M.D. receives research funding from Mallinckrodt unrelated to this work. The other authors declare no conflicts of interest. Portions of this study were presented at the Pediatric Academic Society annual meeting, May 5-8, 2020, Toronto, Canada.

OBJECTIVE: To assess the prevalence of therapy-related kidney outcomes in survivors of Wilms tumor (WT).

STUDY DESIGN: This prospective cohort study included survivors of WT who were ≥5 years old and ≥1 year from completing therapy, excluding those with pre-existing hypertension, prior dialysis or kidney transplant. Participants completed 24-hour ambulatory blood pressure monitoring (ABPM). Abnormal blood pressure (BP) was defined as ≥90th percentile. Masked hypertension was defined as having normal office BP and abnormal ABPM findings. Urine was analyzed for KIM-1, IL-18, EGF, albumin, and creatinine. Estimated glomerular filtration rate (eGFR) was calculated using the bedside CKiD equation. Recent kidney ultrasounds and echocardiograms were reviewed for contralateral kidney size and left ventricular hypertrophy (LVH), respectively. Clinical follow-up data was collected for approximately 2 years following study enrollment.

RESULTS: Thirty-two participants (median age 13.6 [IQR: 10.5-16.3] years; 75% ≥Stage 3 WT) were evaluated at a median of 8.7 years (IQR: 6.5-10.8) post-therapy; 29 participants underwent unilateral radical nephrectomy, two bilateral partial nephrectomy, and one radical and contralateral partial nephrectomy. 72% received kidney radiotherapy and 75% received doxorubicin. Recent median eGFR was 95.6 ml/min/1.73m2 (IQR: 84.6-114.0; 11 (34%) had an eGFR <90). Abnormal ABPM results were found in 22/29 participants (76%), masked hypertension in 10/29 (34%), and microalbuminuria in 2/32 (6%). 22/32 (69%) participants had abnormal EGF; few had abnormal KIM-1 or IL-18. Seven participants with previous unilateral nephrectomy lacked compensatory contralateral kidney hypertrophy. None had LVH.

CONCLUSION: In survivors of WT, adverse kidney outcomes were common and should be closely monitored.