Skin manifestations uncover underlying Follicular helper T-cell lymphoma, angioimmunoblastic-type in an immunosuppressed patient.

In the context of immunosuppression, most lymphoproliferative disorders are of B-cell origin and associated with Epstein-Barr virus (EBV). Follicular Helper T-cell Lymphoma, Angioimmunoblastic type (AITL) is the most frequently encountered T-cell lymphoma subtype. We present a challenging AITL case, initially misinterpreted as a polymorphic EBV + B-cell lymphoma, in a 62-year-old woman with a history of rheumatoid arthritis treated with multiple immunosuppressive agents. Over several years, she developed varied cutaneous manifestations with distinct histopathological infiltration patterns, prompting a diagnostic reassessment. Molecular studies demonstrated T-cell clonality, and RHOA and TET2 mutations, supporting the diagnosis of AITL with associated EBV + B-cell expansion. Notably, the presence of epidermotropic EBV + B-cell infiltrates masked the underlying T-cell neoplasm. This case underscores the importance of integrating histopathological, clinical, and molecular data, and highlights the diagnostic and biological complexity of AITL, particularly when it arises in the setting of immune dysregulation and exhibits features overlapping with EBV-driven B-cell proliferations.