Genomic Insights into p53 Alterations and Chromosome 1p Anomalies for Prognostic Stratification in Childhood Solid...

To analyze the frequency of p53 and 1p anomalies and to study the association of these genetic biomarkers with histopathological and clinical outcomes in childhood solid tumors.

A pilot study was conducted on 28 children with solid tumors up to 12 years of age. Participants were subjected to a needle biopsy. The material was divided into two parts: one placed in saline, for studying 1p loss of heterozygosity (LOH); other placed in formalin fixed, for histopathological examination and p53 analysis. Clinical, histopathological, and outcome status were noted. Statistical methods were applied. Data were also analyzed as any positive (either positive) or no positive (neither positive) to p53 and 1p LOH.

Among 28 pediatric patients, p53 positivity was seen in 10 (36%) cases and 1p LOH in 14 (50%) cases, with 6 (20%) showing both. p53 positivity appeared more frequent in children <4 years in an exploratory subgroup analysis (P = 0.024). Tumors <5 cm were predominantly p53 negative (P = 0.019), while 1p LOH was significantly associated with larger tumors (>5 cm; P = 0.019). p53(-) status was seen in well-differentiated histology (P = 0.041). Either p53 or 1p LOH positivity was significantly linked to large tumors, while other tumor characteristics did not show any significant association. Mortality (n = 2) and relapse (n = 3) were observed only in patients positive for both markers.

The chromosome 1p anomalies were relatively more frequent than reported. 1p LOH showed a significant association with larger tumor size, while p53-negative status was more frequently observed in smaller tumors and well-differentiated histology. However, tumor growth and adverse outcomes appeared more frequent when both markers were present concurrently, suggesting a possible synergistic adverse effect that requires confirmation in larger studies.