Flow cytometric findings in the floral variant of follicular lymphoma.

The floral variant of follicular lymphoma (FL-F) is an unusual variant of follicular lymphoma. The malignant "follicles" have an unusual "floral" appearance due to the proliferation of surrounding and infiltrating small lymphocytes. This variant of malignant lymphoma has been supported by immunohistochemical immunophenotyping and gene-rearrangement studies; however, the flow cytometric findings have not previously been described. We report the flow cytometric findings in two cases of FL-F. The surrounding and infiltrating small lymphocytes represented mantle cells which, in one case, obscured monoclonality in the lymphocyte region. The monoclonal B-cells were CD10+, supporting a follicular center cell origin.