Abnormalities of chromosome 2p23 with expression of ALK1 and p80 occur in both inflammatory myofibroblastic tumor (IMT) and anaplastic large cell lymphoma.
Histology, immunohistochemistry, and T-cell gene rearrangement studies were supportive of a CD 30-positive ALK-1 negative anaplastic large cell lymphoma.
However, CD13 positivity has not previously been described in a case of CD30+ (ALK-1+) anaplastic large-cell lymphoma of presumed null-cell origin without histiocytic differentiation.