Transformation from follicular lymphoma to high-grade B-cell lymphoma/leukemia with additional t(2;8)(p12;q24), with inverse expressions of c-MYC and BCL-2, and light-chain switch.

Transformation from follicular lymphoma (FL) to high-grade B-cell lymphoma/leukemia (BLL) has been reported in patients with additional translocations involving the c-MYC gene. The previously reported cases were related to t(8;14) and t(8;22) but not to t(2;8). Herein is reported an FL that terminated in BLL following additional t(2;8). In accordance with previous reports, increased expression of c-MYC was observed in the present case but, interestingly, BCL-2 expression was inversely decreased after the transformation. In addition, the cell-surface immunoglobulin light-chain of lymphoma cells was initially κ type and was then gradually replaced with the λ type after transformation. Downregulation of BCL-2 and light-chain switch have rarely been reported in previous cases of FL transformation involving c-MYC, suggesting that additional t(2;8) translocation may play a role in these events.