Patología de los tumores neuroblásticos: evaluación pronóstica. Experiencia del centro español de referencia de la SEOP para estudios biopatológicos del neuroblastoma (1992-2005)

Background: Neuroblastic tumors are the most frequent extracranial solid tumors in childhood, and are characterized by a heterogeneous clinic behavior, ranging from a rapid progression of disease to a spontaneous regression. Prognostic indicators that condition such behavior, such as age, staging, histopathology, MYCN oncogene status, ploidy, and diverse chromosomal losses and gains, have been demonstrated. The aim of present work is to describe our experience as reference laboratory for the determination of these prognostic factors in neuroblastic tumors. Methods: Tumor material from patients with neuroblastoma, submitted to our laboratory from 1992 to 2005 has been analyzed. Histopathology following Internacional Neuroblastoma Pathology Classification (INPC) classification, PCR and FISH for MYCN status, static cytometry for ploidy and CGH for chromosomal gains and losses, were performed. Results: The clinical follow-up has demonstrated the prognostic value of INPC, the relationship between diploid-tetraploid DNA content and unfavorable histology, the existence of 20% MYCN amplified cases showing an unfavorable prognosis as well as the presence of chromosomal gains and losses especially 11q-, that confer unfavorable prognosis. Conclusions: We confirm the importance of determining morphological and genetic prognostic parameters in neuroblastic tumors in order to stratify the patients to receive the correct therapy accordingly.