RECOMMENDATIONS FOR MODIFICATION OF TERMINOLOGY OF NEUROBLASTIC TUMORS AND PROGNOSTIC-SIGNIFICANCE OF SHIMADA CLASSIFICATION - A CLINICOPATHOLOGICAL STUDY OF 213 CASES FROM THE PEDIATRIC ONCOLOGY GROUP

To develop consistency in terminology and pathologic criteria, the aut hors reviewed the literature and 213 cases of neuroblastic tumors (NT) registered with Pediatric Oncology Group (POG) protocols 8104 and 844 1. The patients were given standardized therapy stratified according t o POG stage and patient age, and four or more histologic sections of p rimary tumor resected before therapy were available in each of these 2 13 cases. All stages were represented. The recommended nomenclature co mbines conventional terms and criteria with those used by Bove and McA dams and Shimada et al. The main features of the recommended nomenclat ure are as follows: (1) the terms neuroblastoma (NB) and ganglioneurob lastoma (GNB) are retained instead of stroma-poor NB and stroma-rich N B, recommended by Shimada et al.; (2) undifferentiated NB is considere d a subtype separate from poorly differentiated NB; and (3) the term G NB is used only when there is a predominant ganglioneuromatous compone nt admixed with the minor neuroblastomatous component. With the use of these criteria and terms, the Shimada classification was determined i n the 213 cases. The results showed that, even after stratification fo r age, POG stage, and primary site, there is a statistically significa nt difference in survival rate between favorable histologic and unfavo rable histologic prognostic subgroups. The authors recommend that defi nitive prognostic categorization of an NT according to Shimada classif ication should be done only when adequate histologic material is avail able from a primary tumor resected before any other therapy. Categoriz ation done on histologic material from small biopsy specimens, previou sly treated primary tumors, or metastatic sites should be considered t entative.