The role of bone marrow evaluation in the staging of patients with otherwise localized, low-risk neuroblastoma.

Background: Bone marrow aspirations and biopsies are standard staging procedures for neuroblastoma because the tumor frequently metastasizes to the bone marrow. The presence of bone marrow metastases indicates stage 4 or 4S neuroblastoma by International Neuroblastoma Staging System (INSS) criteria; these stages are also associated with other metastatic sites of disease. We questioned whether bone marrow studies changed the staging or treatment of children with localized, completely resected tumors if there was no other evidence of metastatic spread.