Clinicopathological characteristics of follicular lymphoma with peripheral blood involvement

Abstract

This study aimed to indicate patient outcomes and pathological characteristics of follicular lymphoma (FL) with peripheral blood (PB) involvement. Of 533 patients with FL, 56 (11%) had PB involvement. Of the patients treated with rituximab, 39 patients with PB involvement had significantly shorter progression-free survival than 107 patients with stage IV disease without PB involvement (p = 0.021), but the overall survival was not different (p = 0.804). The histopathology of the primary sites was usually nodal (95%) low-grade (86%) FL with IGH/BCL2 fusion (75%). Flow cytometric and immunohistochemical analyses revealed that the incidence of CD10 positivity was lower in the bone marrow (55% and 58%) and PB (41% and not available) than in the primary site (86% and 93%) (p = 0.004 and p = 0.0001, respectively). Therefore, even if small lymphoma cells in the bone marrow and PB are negative for CD10, FL cannot be ruled out.

Keywords::

• Follicular lymphoma
• peripheral blood
• leukemic phase
• CD10
• rituximab

Acknowledgements

The authors would like to thank Ms. C. Kina and Ms. S. Miura for their technical assistance with immunohistochemistry. This work was supported in part by the Foundation for Promotion of Cancer Research and by the National Cancer Center Research and Development Fund (23-A-17, 23-A-23, and 26-A-4) in Japan.

Potential conflict of interest

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