Our study demonstrates that patterns of TCR and TRBC1 expression are notably different in malignant T-lymphoblast populations compared to mature T-cell lymphomas, while highlighting the need to further refine the spectrum of TCR and TRBC expression in immature T-cell proliferations, with particular emphasis on exploring TRBC2 + and TRBC null phenotypes. Here, TRBC1 is linked to T-cell non-Hodgkin lymphoma.