Detection of Isolated Tumor Cells in Neuroblastoma by Immunohistochemical Analysis in Bone Marrow Biopsy Specimens

Evaluation of the bone marrow is a critical component of accurate staging and surveillance for recurrent disease in neuroblastoma. The value of routine immunohistochemical analysis of otherwise histologically negative bone marrow biopsy specimens has not been adequately evaluated. By using synaptophysin, chromogranin, and beta-catenin, immunohistochemical analysis performed on otherwise histologically negative bone marrow specimens identified isolated tumor cells (ITCs) in 9.1%, 5.0%, and 10.0% of 220 biopsy specimens, respectively. Overall survival, as estimated by the Kaplan-Meier method, was not significantly different between patients with and without ITCs (P = .357). Of the immunohistochemical markers evaluated, beta-catenin showed the greatest sensitivity for identifying ITCs in the bone marrow and showed reactivity in primary tumor samples. We found that the presence of ITCs identified by immunohistochemical analysis may predict the persistence of disease but does not show significant overall survival differences. We also identified beta-catenin as a sensitive immunohistochemical marker of primary and metastatic neuroblastoma.