PB0278 - Pediatric Renal Tumors: Clinical Outcomes in Patients With and Without Tumor-related Thrombus

Sunday, June 25, 2023

18:30 – 19:30 ET

Room: Exhibition

Presenting Author(s)

CM

Catherine Mark

Paediatric Haematology Oncology Fellow
The Hospital for Sick Children
Toronto, Ontario, Canada

Co-Author(s)

Laura Avila, MD, PhD

Clinician Scientist
The Hospital for Sick Children
Toronto, Ontario, Canada
JB

Jack Brzezinski

Assistant Professor of Paediatrics
The Hospital for Sick Children
Toronto, Ontario, Canada
Gn

Gabriele Zamperlini netto

Paediatric Haematology Oncology Fellow
The Hospital for Sick Children
Toronto, Ontario, Canada
AL

Armando Lorenzo

Associate Professor of Paediatric Urology
The Hospital for Sick Children
Toronto, Ontario, Canada
JT

Jeffrey Traubici

Assistant Professor of Paediatric Radiology
The Hospital for Sick Children
Toronto, Ontario, Canada
KA

Karem Abdul-Samad

Clinical Research Coordinator
The Hospital for Sick Children
Toronto, Ontario, Canada
NA

Nour Amiri

Clinical Research Project Coordinator
The Hospital for Sick Children
Toronto, Ontario, Canada
Jennifer Vincelli, MN, RN (EC)

Nurse Practitioner
The Hospital for Sick Children
Toronto, Ontario, Canada
BN

Bo Ngan

Associate Professor of Pathology
The Hospital for Sick Children
Toronto, Ontario, Canada
AZ

Antonella Zanette

Paediatric Haematology Oncology Fellow
The Hospital for Sick Children
Toronto, Ontario, Canada
SW

Suzan Williams, MD

Staff Physician
The Hospital for Sick Children
Toronto, Ontario, Canada
RG

Ronald Grant

Paediatric Oncologist
The Hospital for Sick Children
Toronto, Ontario, Canada
Leonardo R. Brandão, MD, MSc (he/him/his)

Staff Hematologist, Thrombosis Program Director, Professor of Paediatrics
The Hospital for Sick Children, University of Toronto
Toronto, Ontario, Canada

Background: Renal tumor-related venous thromboembolism (TR-VTE) affects 5-10% of children; patient characteristics and outcomes of children with TR-VTE remain poorly understood.

Aims: To investigate the characteristics and outcomes of children with TR-VTE vs no TR-VTE. Outcomes included overall survival (OS), disease relapse, and bleeding among patients receiving anticoagulation.

Methods: This single-institution retrospective cohort study included children aged 0-18 years diagnosed with renal tumors between 1990-2021. Ethics approval was obtained. Characteristics and outcomes of children with and without TR-VTE were compared using Wilcoxon Rank Sum, Fisher’s Exact, or Chi-square tests. Survival analysis was employed to estimate the effect of TR-VTE on OS.

Results: In total, 322 patients were diagnosed with renal tumors during the study period; 139 (43%) were male. Median age at tumor diagnosis was 3.4 years (25th-75th percentile 1.5-5.9). Majority, 255 (79%) had Wilms tumor, 26 (8%) renal cell carcinoma, 19 (6%) mesoblastic nephroma, and 22 (7%) other tumors.
Forty-six (14%) had TR-VTE at time of tumor diagnosis. Differences between patients with/without TR-VTE are shown in the Table.
Fifteen (33%) TR-VTE patients received anticoagulation; one clinically relevant non-major bleeding event occurred in a patient receiving therapeutic enoxaparin. Six (13%) TR-VTE patients also had pulmonary embolism (PE), four at presentation and one during anticoagulation; PEs were more frequent in patients with supradiaphragmatic (3/8, 38%) vs infradiaphragmatic TR-VTE (3/35, 9%, p=0.056).
The presence of TR-VTE affected OS; the 5-year OS was 72% (95% confidence interval [CI], 59-89%) in patients with TR-VTE vs 93% (95% CI, 90-97%) in non-TR-VTE, log-rank test p=0.001 (Figure). Controlling for tumor histology, patients with TR-VTE were at higher risk of death (hazard ratio 4.1, 95% CI 1.6-10.2; p=0.003).

Conclusion(s): Age at diagnosis, modified Khorana score, tumor type, and death differed in patients with vs without TR-VTE. Tumor-related VTE impacted OS independently of tumor histology. Anticoagulation was safe, without documented major bleeding events.