Objective: To investigate the feasibility of interphase FISH in the routine clinicopathological practice and its values in the differential diagnosis of lymphomas.
Methods: A total of 74 fresh tissue samples clinically suspicious of lymphoma were investigated by FISH using three probes including IgH/bcl-2, IgH/CCND1 and API2/MALT1, corresponding the translocation t(14;18), t(11;14) and t(11;18) respectively. The results of FISH were analyzed and compared with the histopathologic diagnosis.
Results: Histological evaluation eventually confirmed that there were 62 cases of lymphoma and 12 cases of reactive lymphoid processes. The translocations were detected in 7 cases in 62 cases of lymphoma: 3 demonstrated t(14;18) including 2 cases of follicular lymphomas and 1 nodular sclerosing Hodgkin lymphoma. Four cases had t(11;14) including mantle cell lymphoma (2 cases), follicular lymphoma (1 case) and small cell lymphoma (1 case). A lymphoid hyperplasia case showed detectable t(14;18). All 25 cases of DLBCL showed no evidence of t(14;18). Amplification or loss of regional genes was seen more often in malignant than in the benign cases.
Conclusion: Interphase FISH offers useful ancillary technology that plays an important role in differential diagnosis and classification of lymphoma.