RESUMO
BACKGROUND: The incidence and clinical correlation of MALT1 translocation and numerical aberrations in Korean gastric MALT lymphoma patients have been rarely reported. We studied the incidence and clinicopathologic relationship of these chromosomal aberrations in Korean gastric lymphomas. METHODS: Seventy-six gastric lymphomas, which consisted of 40 low grade MALT lymphoma, 4 high grade MALT lymphoma and 32 diffuse large B-cell lymphoma (DLBCL) cases, were analyzed for the detection of t(11;18) API2-MALT1, t(14;18) IgH-MALT1 and aneuploidies of chromosomes 3 or 18 using fluorescence in situ hybridization. RESULTS: The t(11;18) was demonstrated in 3 low grade MALT lymphomas (7.5%) and one DLBCL, which was associated with advanced stage, deeper invasion, and disease progression or relapse. The t(14;18) was demonstrated in none of these cases. Trisomy 3 and 18 were detected in 8 (11%) and 11 of 76 cases (12.5%) respectively, and found only in translocation-negative cases. Two of 4 high grade MALT lymphomas showed trisomy 18. All patients survived with successful second treatment after progression or relapse. CONCLUSIONS: The t(11;18) API2-MALT1 was not quite frequent in Korean low grade gastric MALT lymphomas and was associated with advanced clinical situations. Overall prognosis was good for long-term follow-up regardless of progression or relapse.