Anaplastic lymphoma kinase (ALK) -positive diffuse large B-cell lymphoma (DLBCL) is a variant of DLBCL, expressing the ALK kinase (Delsol et al., 2008).

The postulated normal counterpart is post-germinal centre B cell with features of plasma cell differentiation.
The immunophenotype typically show ALK+ (cytoplasmic staining). Plasma cell markers such as CD138 test positive, whereas B-cell markers such as CD20 and CD79a are negative, CD30 is usually negative. Cytoplasmic staining for IgA and, less frequently, IgG is typically seen in the majority of cases.

The disease runs an aggressive course (Laurent et al., 2010). Long term survival was reported in some children.

The lymph node sections show large immunoblastic cells with nucleoli.

Chemotherapy using CHOP or CHOP-like regimens is the standard of care. Due to CD20 negativity, the monoclonal antibody rituximab is ineffective.

Median overall survival was 20 months in a study (Laurent et al., 2010).