Although most patients with follicular lymphoma (FL) follow an indolent disease course, some patients experience a critical inflection point when FL transforms into an aggressive lymphoma. Historically, FL transformation is marked by poor outcomes, particularly for patients with previous FL-directed treatment. Compared with FL, transformed FL (tFL) is marked by numerous additional genetic changes, upregulates novel signaling pathways, and arises from an ancestral FL clone with shared FL-initiating mutations. Prediction of tFL risk remains a high-priority area of disease research, with recent work highlighting memory-like B-cell phenotypes associated with transformation risk and implicating critical tumor-immune interactions at transformation emergence. Mechanistic studies provide insight into the role of genetic drivers in determining malignant B-cell phenotypes or reducing microenvironmental dependencies. In parallel, a shifting therapeutic landscape marked by novel immune-based therapeutics is improving outcomes for patients, yet further clinical outcome data in tFL are greatly needed. This review summarizes recent scientific and clinical studies in tFL and provides an updated understanding of the biological basis, diagnosis, and clinical management of tFL. We conclude with a proposed plan of future research aimed at the goal of increasing tFL biologic knowledge and improving outcomes for patients with tFL.
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Follicular Lymphoma|
October 9, 2025
An updated understanding of follicular lymphoma transformation Available to Purchase
Erin M. Parry,
Erin M. Parry
1Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA
2Harvard Medical School, Boston, MA
3Cancer Program, Broad Institute of MIT and Harvard, Cambridge, MA
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Jessica Okosun
Jessica Okosun
4Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
5Department of Haemato-Oncology, St Bartholomew’s Hospital, London, United Kingdom
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Blood (2025) 146 (15): 1812–1823.
Article history
Submitted:
January 2, 2025
Accepted:
April 18, 2025
First Edition:
May 15, 2025
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Citation
Erin M. Parry, Jessica Okosun; An updated understanding of follicular lymphoma transformation. Blood 2025; 146 (15): 1812–1823. doi: https://doi.org/10.1182/blood.2024026016
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