Fc-Epsilon Receptor (CD23) Expressing Follicular Dendritic Cells as a Main Prognostic Factor in Follicular Lymphoma

Fc-epsilon receptor (CD23)-expressing follicular dendritic cells is a main prognostic factor in follicular lymphoma. Falaleeva N. A., Osmanov E. A., Tupitsyn N. N. Federal State Budgetary Institute N. N. Blokhin Russian Cancer Research Center, Health Ministry of Russian Federation, Moscow, Russia SUMMARY Follicular dendritic cells, expressing FceRII or CD23 (FceRIIFDCs) as a component of non-tumor environment have been studied in 232 follicular lymphoma (FL) patients. FceRIIFDCs were found in 87.5% of follicular lymphoma cases and were associated with a nodular pattern of tumor growth (p = 0.000), but not the cytological grade of lymphoma. There were no associations of FceRIIFDC with clinical prognostic factors (FLIPI indices) or with bone marrow involvement in FL patients by histology. The presence of FceRIIFDCs in tumor tissue was an independent prognostic factor according to treatment results, i.e. frequency of CR, duration of OS and PFS. Bone marrow involvement significantly worsened the prognosis in FceRIIFDC-positive group of patients. We suggest a new prognostic index (FDC-IP) that allows biochemical identification of the following patient groups: FceRIIFDC-positive patients without bone marrow involvement (good prognosis), FceRIIF-DC-positive patients with bone marrow involvement (intermediate prognosis), FceRIIFDC-negative patients (poor prognosis). These 3 groups significantly differ (p = 0.000) both in OS and in PFS. This is the first evidence of the possibility to assess tumor behavior and treatment results in FL according to lymphoma biochemical and other than clinical parameters.