BCL6 and diffuse large B-cell lymphoma: Immunohistochemistry results were as follows; Ki-67 80%, CD20 (+), BCL2 (+), BCL6 (+), MUM1 (+), C-MYC (−), nongerminal center type DLBCL, and fluorescence in situ hybridization negative for c-myc by cervical lymph node biopsy.