BCL6 gene rearrangement is the most frequent chromosomal abnormality in Diffuse large B-cell lymphoma (DLBCL). Rearrangement of BCL6 proto-oncogene at chromosome band 3q27 is seen in nearly 35% cases of DLBCL. Presence of a BCL6 gene fusion can be useful in diagnosing and sub-classifying B-Non Hodgkin Lymphomas. It can also indicate prognosis in B-cell lymphoma with features intermediate between DLBCL and Burkitt lymphoma, in association with BCL2 ; MYC gene fusions. This chromosomal abnormality has also been detected in 6-15% cases of Follicular centre lymphomas.