[Immunologic identification of undetectable neuroblastoma cells by current cytohistological studies of bone marrow...

Immuno-alkaline phosphatase staining (APAAP technique) has been used to identify neuroblastoma cells on bone marrow samples from 12 children at various stages of the disease. On 72 occasions immunological analyses were performed using a panel of monoclonal antibodies which selectively bind to cells of neuroectodermal origin. In 57 of these procedures, tumor cells were detected, whereas histological and cytological analyses revealed pathological cells in 45 and 37 cases respectively. Reactivity of minimal residual tumor cells--mainly with three MAbs (UJ13A, UJ167.11, A2B5)--points to the fact that these cells belong to a resistant neuroblastoma clone, which remains in bone marrow despite intense therapy. Our study demonstrates that immunological staining may identify and define a small number of neuroblastoma cells which are not yet detectable by traditional histological and cytological criteria.