Post-CAR T cell therapy lymphoproliferative disorders are rare lymphoproliferative and lymphomatous complications that arise after car t cell therapy, with an incompletely characterized clinical and biological spectrum. They can include both CAR-transgene-positive and transgene-negative lymphomas, and causal attribution is often difficult because multiple contributing factors may coexist. Proposed mechanisms include car transgene vector integration, pre-existing clonal haematopoiesis, and dysregulated signalling pathways, all of which may promote clonal expansion or transformation. These proliferations often emerge in settings of immune suppression or viral reactivation, highlighting the importance of host context in pathogenesis. A 2026 Nature Reviews Clinical Oncology article emphasized the spectrum, pathobiology, mechanistic insights, and diagnostic challenges of this entity (PMID:41986503).
Lymphoproliferative disorders after CAR T cell therapy
- Rare post-treatment lymphoproliferative and lymphomatous disorders have been described after car t cell therapy, but their clinical and biological spectrum remains incompletely characterized. (PMID:41986503)
- Reported cases include both CAR-transgene-positive and transgene-negative lymphomas, underscoring heterogeneity in origin and mechanism. (PMID:41986503)
- Causal attribution is challenging because the disorders may reflect therapy-related effects, pre-existing clonal processes, or other concurrent drivers. (PMID:41986503)
- A 2026 Nature Reviews Clinical Oncology review highlighted diagnostic challenges and mechanistic uncertainty in this setting. (PMID:41986503)
Mechanistic and contextual factors
- car transgene vector integration is mentioned as a rare factor that might promote clonal expansion or transformation. (PMID:41986503)
- Pre-existing clonal haematopoiesis is discussed as a potential contributor to these post-therapy proliferations. (PMID:41986503)
- dysregulated signalling pathways are also implicated as possible drivers of clonal expansion or transformation. (PMID:41986503)
- These disorders often emerge in the context of immune suppression and viral reactivation, suggesting that impaired immune surveillance may facilitate outgrowth. (PMID:41986503)