Pediatric core needle biopsy: Strengths and limitations in evaluation of masses

Needle core biopsies (NCB) are widely used in adults but are less often use d for the evaluation of pediatric tumors. To determine the diagnostic utili ty of NCB for pediatric tumors, we performed a retrospective analysis. Fift y NCB of masses from 1992 to 1998, subsequent pathologic specimens, and med ical records were reviewed. All patients were less than 21 years of age. Of the NCB 78% (39/50) were diagnostic of a neoplasm, 8% (4/50) were nondiagn ostic in cases where a tumor was subsequently diagnosed, and 14% (7/50) rev ealed inflammatory or reactive lesions, with no subsequent diagnosis of a n eoplasm according to medical record review. In cases in which a neoplasm wa s present, NCB was diagnostic in 91% (39/43). For cases in which there was a previous diagnosis of a tumor, 100% (9/9) of NCB were diagnostic of a rec urrence or metastasis. In cases of NCB for primary tumor diagnosis, 88% (30 /34) were diagnostic. The most common problems encountered were related to specimen adequacy, such as insufficient tissue, crush artifact, and tumor n ecrosis. Tumor diagnoses were as follows: primitive neuroectodermal tumor ( PNET)/Ewing sarcoma (12), malignant lymphoma/Hodgkin's disease (8), rhabdom yosarcoma (4), germ cell tumor (3), Wilms' tumor (3), neuroblastoma (1), sa rcoma, not otherwise specified (4), and other neoplasms (8). There were no complications of the procedure. NCB of pediatric tumors is an effective dia gnostic tool and can be used to obtain diagnostic material quickly and safe ly. NCB was diagnostic in 90% of cases in this series. When NCB provide suf ficient material for immunohistochemical. cytogenetic, flow cytometric, and other ancillary studies, the diagnostic efficacy is enhanced. The major li mitations in this series were related to sampling problems and specimen ade quacy for comprehensive pathologic evaluation.