Nodal T-Follicular Helper Cell Lymphoma, Angioimmunoblastic-Type, Diagnosed in a Patient with Psoriasis Following COVID-19 Vaccination under Adalimumab Treatment: A Causal Association?

Biologics have expanded the armamentarium for psoriasis, but there has been a growing concern about the risk of lymphoma in patients under tumour necrosis factor (TNF)-α inhibitor and methotrexate. Besides, the mRNA-based coronavirus disease 2019 (COVID-19) vaccination was known to stimulate the proliferation of T-follicular helper cells. We report a case of a patient with psoriasis under adalimumab developing nodal T-follicular helper cell lymphoma, angioimmunoblastic-type following the mRNA-1273 COVID-19 vaccine. We suspect that adalimumab, methotrexate, Epstein-Barr virus (EBV) reactivation, previous reactive lymphoid hyperplasia and psoriasis per se predispose our patient to a lymphoma-prone condition, and the two doses of the mRNA vaccine act as the last straw.