Pancreatoblastoma : Molecular Genetics

Comments:
Molecular Genetics: More than 80% of pancreatoblastomas show loss of 11p chromosome. A small percentage of pancreatoblastomas show association with Beckwith-Wiedemann syndrome which also shows loss of heterozygosity at the same location (11p).

Another common finding (50-80% of cases) is aberrant activation of Wnt signaling pathway either via somatic mutations in CTNNB1 (90%) or APC gene (10%). The abnormal cytoplasmic and nuclear accumulation of β-catenin can be demonstrated immunohistochemically. Abnormalities in genes typically involved in ductal adenocarcinoma of pancreas (TP53, KRAS) are not seen.

About this image: Acinar structures, solid sheets, as well as squamoid nests are present in a background of abundant spindle stroma.