SURGICAL-MANAGEMENT AND OUTCOME OF LOCOREGIONAL NEUROBLASTOMA - COMPARISON OF THE CHILDRENS CANCER GROUP AND THE INTERNATIONAL STAGING SYSTEMS

Although precise anatomic staging is prognostically important in neuroblastoma, most widely employed staging systems remain incompatible. The international Neuroblastoma Staging System (INSS) was formulated to incorporate the basic elements of several systems to and define the significance of tumor resectability, anatomic ''midline,'' and lymph node involvement. The authors sought to determine the applicability and value of the INSS compared with the classic Evans system. Between 1980 and 1999, 424 children with the diagnosis of local or regional neuroblastoma were entered in Childrens Cancer Group (CCG) clinical trials. The patients were assigned to Evans stage I, II, or III, by clinical and surgicopathologic assessment, and were treated uniformly by Group-wide therapy protocols. INSS stage 1, 2A, 2B, or 3, was applied, by retrospective analysis, to the children in the earlier studies, and by prospective evaluation of recent patients in the current studies. Survival and relapse-free survival (RFS) rates were determined and compared, based on age at diagnosis, extent of resection, and staging reassignment. All 87 Evans stage I patients were classified as INSS stage 1 and had a 92% 3-year RFS rate. Of the 144 Evans stage II patients, 65 also qualified as INSS stage 1 patients, with an 82% RFS rate. The other 79 stage II children remained in INSS stage 2A or 28 and had a 70% RFS rate (P =.10). Of the 193 Evans stage III patients, 24 were reassigned to INSS stage 1 (85% RFS rate) and 33 to stage 2A or 28 (65% survival rate; 61% RFS rate). The other 136 stage III children stayed in INSS stage 3 and had a 62% survival rate and a 58% RFS rate (P =.04). Among the Evans Ill patients who were also INSS stage 3, the following variables showed significant differences with respect to RFS rates: age at diagnosis (97% RFS rate for those under 1 year of age, compared with a 47% RFS rate for those 1 year of age or older; P =.0001) and eventual extent of resection (complete, 86% RFS rate; partial, 56% RFS rate; P=.0004); however, these variables were not independent ones for stage 1 or 2, The INSS requires careful surgical implementation and may be the most effective method to stratify outcome for intermediate-risk patients. Copyright (C) 1995 by W.B. Saunders Company