[Successful treatment of CD30-positive nodal follicular helper T-cell lymphoma, follicular type, with A-CHP and tucidinostat].

Nodal T follicular helper cell lymphoma, follicular type (nTFHL-F), is an exceptionally rare subtype of peripheral T-cell lymphoma derived from T follicular helper cells. Although diagnostic criteria have been refined in recent classifications, standardized therapeutic strategies have yet to be established. Although molecular evidence indicates that the histone deacetylase inhibitor tucidinostat is preferentially active against tumors with a TFH phenotype, quantitative clinical data remain limited, and no subtype-specific analyses have been reported to date. We encountered a case of CD30-positive nTFHL-F in which first-line treatment with A-CHP chemotherapy, incorporating brentuximab vedotin, achieved a complete metabolic response (CMR). The patient was a 71-year-old man who presented with left cervical lymphadenopathy and was diagnosed with nTFHL-F based on histopathological and immunophenotypic findings. Given the CD30 positivity, A-CHP was selected, and six cycles were completed, resulting in a CMR on PET-CT. Although the response only lasted approximately six months before relapse occurred, subsequent treatment with tucidinostat induced a second objective response. Reports describing the efficacy of A-CHP and tucidinostat in CD30-positive nTFHL-F are extremely rare, and this case provides clinical insight into treatment sequencing and response durability in this setting.