Safety and Diagnostic Accuracy of Tumor Biopsies in Children With Cancer

BACKGROUNDTumor biopsies are central to the diagnosis and management of cancer and are critical to efforts in personalized medicine and targeted therapeutics. In the current study, the authors sought to evaluate the safety and accuracy of biopsies in children with cancer. METHODSAll biopsies performed in children at the study institution with a suspected or established diagnosis of cancer from 2003 through 2012 were reviewed retrospectively. Patient characteristics and disease-related and procedure-related factors were correlated with procedure-related complications and diagnostic accuracy using logistic regression analysis. RESULTSA total of 1073 biopsies were performed in 808 patients. Of 1025 biopsies with adequate follow-up, 79 (7.7%) were associated with an adverse event, 35 (3.4%) of which were minor (grade 1-2) and 32 (3.1%) of which were major (grade 3-4) (grading was performed according to the National Cancer Institute Common Terminology Criteria for Adverse Events [version 4.0]). The most common major adverse events were blood transfusion (>10 mL/kg; 24 cases) and infection requiring intravenous antibiotics (6 cases). Eleven deaths (1.4%) occurred within 30 days after the procedure, but the procedure may have contributed to the outcome in only 2 cases. A total of 926 biopsies (90.3%) provided definitive histologic diagnoses. Using multivariable analysis, biopsy site, preprocedure hematocrit level, and body mass index were found to be associated with the risk of postprocedural complications (P<.0001, P<.0001, and P =.0029, respectively). Excisional biopsy and biopsy site were found to be independently associated with obtaining a diagnostic result (P =.0002 and P =.0008, respectively). CONCLUSIONSTumor biopsies in children with cancer are associated with a low incidence of complications and a high rate of diagnostic accuracy. The predictive factors identified for adverse outcomes may aid in risk assessment and preprocedural counseling. Cancer 2015;121:1098-1107. (c) 2014 American Cancer Society. In addition to establishing the diagnosis of cancer, tumor biopsies are being increasingly used for determining the presence of molecular targets, confirming pharmacodynamic effects, and tumor banking. Nevertheless, to the authors' knowledge, the risks and accuracy of these procedures in pediatric patients with cancer are unknown. In the current review of an extensive experience, the authors found that tumor biopsies in children are associated with an acceptably low incidence of clinically relevant adverse events (<8%) and have a high diagnostic accuracy (>90%).