[Cytologic detection of neuroblasts in the bone marrow].

Cytological detection of bone marrow involvement by neuroblastoma is improved by sampling at ten sites because metastatic cells have a multifocal distribution. Examination of spread films from ten bone marrow aspirates has been compared to density separation of the pool of bone marrow aspirates followed by cytocentrifugation onto glass slides. Of 103 procedures performed, 3 positive results by concentration of the pool were found negative by examination of spread films from each bone marrow aspirate. Cytological examination of the pool of bone marrow aspirates after density separation is a simple, rapid and accurate technique for the detection of small aggregates of metastatic cells in patients with neuroblastoma. Additional immuno-enzymatic techniques may be used for the detection of isolated neuroblastoma cells.