Neuroblastoma: morphological pattern, molecular genetic features, and prognostic factors

• Published in: Uspehi molekulârnoj onkologii Vol. 3; no. 1; pp. 32 - 43
• Main Authors: Stroganova, A. M., Karseladze, A. I.
• Format: Journal Article
• Language: English
• Published: ABV-press 25.04.2016
• Subjects: amplification heterogeneity; amplification of sequences; chromosomal aberrations; classification; histological pattern; history of study; mycn gene amplification; neuroblastoma; prognostic factors
• ISSN: 2313-805X; 2413-3787
• DOI: 10.17650/2313-805X.2016.3.1.32-43

Neuroblastoma, the most common extracranial tumor of childhood, arises from the developing neurons of the sympathetic nervous system (neural cress stem cells) and has various biological and clinical characteristics. The mean age at disease onset is 18 months. Neuroblastoma has a number of unique characteristics: a capacity for spontaneous regression in babies younger than 12 months even in the presence of distant metastases, for differentiation (maturation into ganglioneuroma) in infants after the first year of life, and for swift aggressive development and rapid metastasis. There are 2 clinical classifications of neuroblastoma: the International neuroblastoma staging system that is based on surgical results and the International Neuroblastoma Risk Group Staging System. One of the fundamentally important problems for the clinical picture of neuroblastoma is difficulties making its prognosis. Along with clinical parameters (a patient’s age, tumor extent and site), some histological, molecular biochemical (ploidy) and genetic (chromosomal aberrations, MYCN gene status, deletion of the locus 1p36 and 11q, the longer arm of chromosome 17, etc.) characteristics of tumor cells are of considerable promise. MYCN gene amplification is observed in 20–30 % of primary neuroblastomas and it is one of the major indicators of disease aggressiveness, early chemotherapy resistance, and a poor prognosis. There are 2 types of MYCN gene amplification: extrachromosomal (double acentric chromosomes) and intrachromosomal (homogenically painted regions). Examination of double acentric chromosomes revealed an interesting fact that it may be eliminated (removed) from the nucleus through the formation of micronuclei. MYCN oncogene amplification is accompanied frequently by 1p36 locus deletion and longer 17q arm and less frequently by 11q23 deletion; these are poor prognostic factors for the disease. The paper considers in detail the specific, unique characteristics of the biological behavior of neuroblastoma, which are untypical of other tumors; histological structure; determinants of the prognosis of the disease, including MYCN gene status; and mechanisms for formation of the amplification and elimination of amplified sequences from the nucleus.