Multifocal neuroblastoma - Biologic behavior and surgical aspects

BACKGROUND. Although multifocal neuroblastoma is rare, its incidence has in creased because of recent improvements in diagnostic tools and the introduc tion of mass screening. Among the 106 neuroblastoma cases treated at the au thors' hospital between 1984 and 1998, 8 were multifocal neuroblastoma. METHODS. The authors examined clinicopathologic findings and biologic featu res, including MYCN amplification, NTRK1 and Ha-ras p21 expression, cellula r DNA content, and telomerase activity in these 8 multifocal neuroblastoma cases. Moreover, clinicopathologic findings were investigated with a review of 53 published cases of multiple neuroblastoma in the literature publishe d in English between 1966 and 1999. RESULTS. Among these eight cases, five were detected by mass screening and three were incidental neuroblastomas. Histologically, all tumors were class ified as ganglioneuroma or favorable neuroblastoma except one advanced case . All tumors lacked the MYCN gene amplification and expressed NTRAK1 mRNA a nd Ha-ras p21 protein. Cellular DNA content showed that half of these tumor s were near-triploid, and the proliferative index (%S-phase) of all tumors was less than 25%. High telomerase activity was detected in none of these c ases. Four patients underwent multistage operation and five patients with b ilateral adrenal neuroblastomas underwent tumor enucleation to preserve adr enal function. Currently, all patients are disease free and none have requi red corticosteroid replacement therapy. Among the previously reported 53 ca ses with multifocal neuroblastoma, 25 were incidentally detected, 18 had fa miliar history, and most patients without other major complications also ha d extremely good prognoses. CONCLUSIONS. These findings suggested that most multifocal neuroblastomas h ave favorable biologic features. Clinically, surgical approaches should be attempted to preserve organ function, especially adrenal function, and mini mal invasive surgery should be performed. In cases of thoracoabdominal neur oblastoma, multistage surgery is effective and safe. Cancer 2000;88:1955-63 . (C) 2000 American Cancer Society.