Monoclonal Antibodies Used for the Diagnosis of the Small Round Cell Tumors of Childhood

Neuroblastoma, rhabdomyosarcoma, Ewing’s sarcoma, acute lymphoblastic leukemia/lymphoma, and the blastematous component of Wilms’ tumor can be grouped together as the small round blue cell tumors of childhood. ¹ While it is often relatively straightforward to arrive at a diagnosis on clinical and conventional pathological information, in a small proportion of cases this is not the case. The pathologist can be left in doubt about the origin of a tumor when presented with biopsies consisting of small uncharacteristic cells with hyperchromatin nuclei and scanty cytoplasm. The accurate classification and subclassification of these tumors is far from academic, particularly as combination chemotherapy has become more specialized.