The cytogenetic exploration of malformative syndromes associated to tumours historically allowed to describe constitutional chromosomal abnormalities of major interest for the understanding of oncogenesis pathways of the most frequent sporadic tumours (del 11p13 and WT1; del 13q14 and Rb1). So, a rare and even exceptional clinical presentation can enrich the knowledge of a common pathology. Our objective is to analyze in a detailed and multidisciplinary way the largest number of possible cases of unusual presentation associating pediatric Tumor And abnormality of Development (TAD).