mdm-2 oncoprotein expression associated with deletion of the long arm of chromosome 12 in a case of mantle cell lymphoma with blastoid transformation [corrected].

We report a unique case of mantle cell lymphoma in blastoid transformation associated with deletion of the long arm of chromosome 12 and with 90 kDa mdm-2 protein overexpression. Neither the mantle cells nor their blastoid counterparts expressed p53 gene product by immunohistochemical analysis. This seems to be the first reported case of this subtype of lymphoma associated with these specific cytogenetic and molecular genetic abnormalities.