The absence of the expression of CD5, CD10, CD11c and CD103 (in 95%, 100 96 and 100% of cases, respectively) is in contrast with most other mature lymphoid malignancies (chronic lymphocytic leukemia, mantle cell lymphoma, follicular lymphoma and hairy cell leukemia) except of marginal zone lymphoma (MZL), thus helping in their distinction. This evidence concerns the gene MME and marginal zone lymphoma.