Both angioimmunoblastic T-cell lymphoma (AITL) and peripheral T-cell lymphoma of the TFH phenotype exhibit the expression of follicular helper T cell markers. Differential expression and coexpression of these markers in malignant and benign lymphoid proliferations are not well understood. This study, published in the American Journal of Clinical Pathology, examined the expression of these markers in lymphoid proliferations.
The researchers performed programmed death-1 (PD-1), C-X-C motif chemokine ligand 13 (CXCL13), inducible costimulator (ICOS), CD10, and B-cell lymphoma 6 protein (BCL-6) immunohistochemistry on several lymphoid proliferations, including classic Hodgkin lymphoma (CHL).
The different lymphoid proliferations included in the study showed differential expression of follicular helper T cell markers. AITL coexpressed more than two TFH markers, while TFH markers were also found in the background T cells of other forms of lymphoma, including CHL. CHL background T cells were found to express all TFH markers other than CD10. The researchers concluded that these findings could complicate the diagnosis of AITL, especially when samples are limited [1].
Source:
[1] Abukhiran, I., Syrbu, S. I., & Holman, C. J. (2021). Markers of follicular helper T cells are occasionally expressed in T-cell or histiocyte-rich large B-cell lymphoma, classic Hodgkin lymphoma, and atypical paracortical hyperplasia: a diagnostic pitfall for T-cell lymphomas of T follicular helper origin. American Journal of Clinical Pathology, 156(3), 409–426. https://doi.org/10.1093/ajcp/aqaa249
