Follicular Lymphoma with Progression to Diffuse Large B-Cell Lymphoma and Concurrent CD5-Negative Mantle Cell Lymphoma-3 Entities in a Lymph Node

Abstract

A 68-year-old woman with a history of follicular lymphoma had pathological findings of grade 3B follicular lymphoma, mantle cell lymphoma (MCL), and diffuse large B-cell lymphoma (DLBCL) identified in 1 lymph node. The DLBCL appeared to be a transformation of the follicular lymphoma. The nodules were diffusely and strongly positive for CD20, BCL6, and BCL2. CD43 highlighted smaller lymphocytes in a fraction of the nodules. BCL1 staining was variable with a mixture of nodular and mantle zone patterns. The diffuse areas showed weaker positivity for CD10, BCL2, and BCL6. CD3 and CD5 highlighted intermixed T cells. The Ki-67 proliferative index was overall estimated to be 60%. Fluorescent in situ hybridization performed on the lymph node was positive for CCND1/IGH. The patterns of BCL1 and BCL6 staining demonstrated 2 separate populations of neoplastic B lymphocytes.

Low-grade follicular lymphoma involvement of the bone marrow with a mixed paratrabecular, diffuse, and massive pattern expressing typical mantle cell lymphoma immunophenotype CD23−/FMC7+: a case report

“…Composite lymphoma is defined as the simultaneous presence of 2 morphologically and immunophenotypically different lymphomas at the same site, and a case with composite FL and MCL has been reported [ 6 ]. The coexistence of MCL and FL has been reported in 12 cases; most showed 2 lymphomas adjacent to each other and 1 showed an intermixed pattern of CD5-negative MCL and FL [ 8 ]. Although our case showed typical MCL immunophenotype CD23−/FMC7+, CCND1 rearrangements, which are diagnostic findings in MCL, were not present.…”