Table 1.
Clinicopathological Findings and Genetic Alterations in Pancreatoblastomas
| Case | Age/sex | K-ras | p53 Accumulation | Dpc4 loss | Nuclear β-catenin accumulation, % | β-Catenin | APC alterations | 11p LOH |
|---|---|---|---|---|---|---|---|---|
| P1 | 5 /M | Wild type | − | − | 25 | N32H | N/E | − |
| P2 | 3 /M | N/A | − | − | 15 | Wild type | N/A | N/A |
| P3 | 4 /M | Wild type | − | N/A | 25 | S33F | N/E | N/I |
| P4 | 45 /F | Wild type | − | + (diffuse) | 90 | S37F | N/E | + |
| P5 | 51 /F | Wild type | − | + (focal) | 40 | Wild type | Germline + LOH | + |
| P6 | 6 /M | Wild type | − | − | − | Wild type | Wild type | + |
| P7 | 13 /F | Wild type | − | − | − | Wild type | Wild type | + |
| P8 | 5 /F | Wild type | − | − | 90 | G34R | N/E | + |
| P9 | 3.5 /F | Wild type | − | − | 40 | N32H | N/E | + |
Locations of somatic mutations in β-catenin are shown by codon.
Nuclear β-catenin accumulation was evaluated based on the percentage of strongly staining tumor cell nuclei. Cytoplasmic accumulation was found to mirror nuclear staining in pancreatoblastomas.
LOH, loss of heterozygosity; N/A, DNA did not amplify or immunohistochemistry failed; N/E, not evaluated due to the presence of mutation detected elsewhere; N/I, noninformative for allelic loss assays.