Optimal Diagnostic Yield Achieved With On-site Pathology Evaluation of Fine-Needle Aspiration--Assisted Core Biopsies for Pediatric Osseous Lesions.

Context.--Image-guided, fine-needle aspiration--assisted core needle biopsy with an on-site evaluation by a pathologist (FNACBP) of osseous lesions is not a common practice in pediatric institutions. Objectives.--To evaluate the diagnostic adequacy and accuracy of FNACBP for pediatric osseous lesions and to compare the adequacy with procedures that do not use fine-needle aspiration. Design.--Six-year, retrospective review of 144 consecutive children biopsied for osseous lesions with and without fine-needle aspiration assistance. Results.--Pathologic diagnosis was achieved in 79% (57 of 72) of the core biopsies without an on-site evaluation, 78% (32 of 41) of the open biopsies (9 with intraoperative consultation), and 97% (30 of 31) of the FNACBPs as the initial diagnostic procedure. Three FNACBP cases were preceded by nondiagnostic open biopsies. Among 34 lesions sampled by FNACBP, 33 (97%) succeeded with diagnostic tissue, with most (30 of 33; 91%) being neoplasms, including 16 malignant (48%), 13 benign (39%), and 1 indeterminate (3%) lesions. The mostcommon diagnoses were osteosarcoma (9 of 33; 27%) and Langerhans cell histiocytosis (7 of 33; 21%). In cases with follow-up information available, 93% (28 of 30) of the FNACBP-rendered diagnoses were clinically useful, allowing initiation of appropriate therapy. The FNACBP procedure had 100% specificity, sensitivity, and positive predictive value for all 14 malignant lesions, with the sensitivity being 88% in benign lesions. Most FNACBP procedures (32 of 34; 94%) yielded adequate material for ancillary testing. A gradual upward trend was observed for the choice of FNACBP as an initial diagnostic procedure for osseous lesions. Conclusions.--The FNACBP procedure yields sufficient material for diagnosis and ancillary studies in pediatric, osseous lesions and may be considered an initial-diagnostic procedure of choice. [ABSTRACT FROM AUTHOR]