Immuno histochemistry and immunophenotypic analyses were positive for Cyclin D1 (Fig 6), CD20 (Fig 7), CD5 (Fig 8) and CD 79a (Fig 9), but negative for BCL6, CD23 and CD10, thus confirming the diagnosis of mantle cell lymphoma (Fig 10). The gene discussed is FCER2; the disease is mantle cell lymphoma.